Organic, Gas, and Element Geochemistry of Hydrothermal Fluids of the Newly Discovered Extensive Hydrothermal Area in the Wallis and Futuna Region (SW Pacific).
Although back-arc settings are favourable environments for the formation of hydrothermal convection cells, hydrothermal exploration has long been conducted to a greater extent on Mid-Oceanic Ridges (MOR). Today, more than 600 active hydrothermal vent fields have been discovered and about half of them are located at MOR against a fifth in back-arc basins (BAB) . Yet back-arc environments are likely to generate more diversity than their MOR homologs in terms of fluid chemistry because of the variety of lithologies the fluids can react with (e.g., basaltic to rhyolitic volcanic rocks with or without arc-like geochemical signature, various alteration mineralogical assemblages) as well as the possible contribution of magmatic-related aqueous fluids [2-5]. The Wallis and Futuna area was surveyed for hydrothermal activity because of its very peculiar geological settings within a back-arc system and its potential relevance for mineral resources [6, 7]. It is located about 200 km west of the northern tip of the Tonga-Kermadec trench where the fastest subduction rates have been recorded (18 to 24 cm per year) and occur at the junction of 2 BAB: the Lau and the North-Fiji BAB . Here we report on the geochemistry of the fluids of the very first two vent fields discovered in the area and in this type of environment. We chose to bring a special focus on organic geochemistry because it has been hardly studied in modern hydrothermal systems despite the recent growing interest for organic matter (OM) in the ocean. The discussion focuses on processes controlling the geochemistry as well as implications of the presence of organic molecules at the local and regional scales.
Organic geochemistry of hydrothermal fluids has generally been far less studied than the mineral and gas geochemistry. In most cases works focused on small molecules (hydrocarbon gases, volatile fatty acids, and amino acids) and very few data are available on semivolatile organic compounds (SVOCs). Despite the growing interest for OM in the ocean and hydrothermal systems there is still a major lack in identification and quantification of organic compounds [10-15]. Notably numbers of studies agree on the major ligand role of organics in metal stabilisation, transportation, bioavailability, and ore-forming but there are hardly any clues on the nature of these ligands in hydrothermal environments [16-25]. Organic compounds in hydrothermal fluids may come from marine dissolved organic matter (DOM) recycling [12, 13], subsurface biomass degradation , entrainment of organic detritus from local recharge zones, and subsequent degradation, or abiotic formation in the deep subsurface [27-30]. The latter is supported by many theoretical [31-33] and experimental work summarised in two reviews [34, 35]. Conversely, some other studies reported the absence of organic compounds in hydrothermal fluids except at the Lost City alkaline vent field which is theoretically more favourable for abiotic synthesis . Nevertheless, we report here the presence of semivolatile organic compounds in hydrothermal fluids from the Wallis and Futuna area and provide concentrations of a selection of extractable compounds that have been identified elsewhere as hydrothermally derived [27, 37]: n-alkanes, n-fatty acids (n-FAs), mono-, and polyaromatic hydrocarbons (BTEXs and PAHs). These very first quantitative field data might feed thermodynamic models of abiotic synthesis, guide the design of experiments to better understand hydrothermal organic geochemistry, and help assessing the importance of hydrothermally derived organic compounds in metal complexation and, as a nutrient for microorganisms, complete fluxes calculation and enter in the carbon cycle budget calculations.
2. Geological Settings
Wallis and Futuna Islands are located at the transition between the North Fiji and the Lau back-arc basins. This geodynamical setting accounts for complex volcanic and tectonic activity in the area. Pelletier et al.  and Fouquet et al.  observed multiple active extensional zones including widespread areas composed of numerous individual volcanoes (e.g., Southeast Futuna volcanic zone (SEVZ)) and well organised spreading centers such as the Futuna and Alofi oceanic ridge. West of Futuna Island, the 20-30[degrees] trending Futuna spreading center (FSC), is composed of a series of en echelon spreading segments. The opening rate of this oceanic ridge has been estimated at 4 cm/yr from the interpretation of magnetic anomalies . East and southeast of Futuna Island, bathymetric maps, and reflectivity data clearly reveal that active extension and recent volcanism occur in the SEVZ as well as along the Alofi spreading center . The SEVZ is a broad zone of diffuse volcanism bordered by the ENE-WSW trending volcanic graben (named Tasi Tulo graben) to the north and the NNE-SSW trending Alofi spreading center to the south. The SEVZ includes Kulo Lasi active volcano, the Fatu Kapa, and Tasi Tulo volcanic zones (, Figure 1).
Fluids were sampled at the Kulo Lasi and Fatu Kapa sites. Kulo Lasi has been described in detail by Fouquet and collaborators . In summary, it is a shield volcano located about 100 km southeast of Futuna Island (Figure 1). It represents the most recent volcano in the SEVZ and is composed of basaltic to trachy-andesitic lava with no direct geochemical affinity with subduction . The volcanic edifice is ca. 20 km in diameter and appears relatively flat with the top located at a depth of 1200 m and the base only 300 m deeper (ca. 1500 m below sea level). It exhibits a central caldera (5 km in diameter and 200-300 m deep) with a flat bottom covered by recent lavas and a central mound composed of older and tectonised lava flow. By contrast, the Fatu Kapa volcanic area is in a 20 km wide transition zone between the Tasi Tulo graben and the Kulo Lasi volcano. Here only small (<1 km) volcanic edifices are seen to be consisting of young mafic to felsic lavas (Figure 1).
3. Sampling and Analytical Procedures
Sampling was achieved at Kulo Lasi and Fatu Kapa by the HOV Nautile during the FUTUNA 1 and FUTUNA 3 cruises conducted by Ifremer in 2010 and 2012. Fluid samples were taken at the nose of smokers to minimise seawater contamination. Samples of volumes up to 750 mL of hydrothermal fluids were collected in titanium syringes that were modified after the model described in Von Damm et al. . The gas-tightness was greatly improved and ensured the majority of the gas to be recovered. Those same syringes have been used in several studies by Charlou et al. and have shown good results notably for gas-Mg correlations (e.g., Charlou et al., 2002). Autonomous temperature sensors ([S.sub.2]T 6000-DH, NKE Instrumentation) were mounted on the sampler nozzle. As soon as the fluids were recovered, pH, [H.sub.2]S, and [Cl.sup.-] concentrations were measured to evaluate the quality of the sample. Total gases were immediately extracted and analysed; then aliquots of gas were conditioned for further stable isotopes measurements. Finally, the gas-free fluid was conditioned for major and minor elements analyses, on the one hand, and for organic compounds analyses, on the other hand.
3.1. Gas Extraction and Analyses. Total gas was extracted as described in Charlou and Donval . Preliminary major gases (C[O.sub.2], [H.sub.2], C[H.sub.4], and [N.sub.2]) concentrations were obtained on board by using a portable chromatograph (Microsensor Technology Instruments Inc.) that was mounted on line with the gas extractor. Extracted gases were conditioned on board in stainless steel pressure-tight flasks and stored until analyses. Gases were separated by Gas-Chromatography (Agilent GC 7890A, Agilent Technologies) and quantitatively analysed by triple detection using mass (MS 5975C, Agilent technologies), flame ionisation, and thermal conductivity detectors. Aliquots of gas were stored both in vacuum tight tubes (Labco, Ltd.) and in copper tubes to be sent for further carbon isotope analyses (Isolab b.v., Netherlands) and He isotopes analyses (CEA, Saclay, France), respectively
3.2. Inorganic Geochemistry: Sample Preparation and Analyses. pH was measured using a combined glass electrode (Ecotrode Plus, Metrohm). [Cl.sup.-] and [H.sub.2]S were measured by potentiometry using AgN[O.sub.3] (0.05 M) and Hg[Cl.sub.2] (0.01 M) as titrating solutions, respectively. NaOH (2 M) was added to the aliquot before [H.sub.2]S measurement. S[O.sub.4], Br, Na, K, Mg, Ca, Li, and Cl were measured by ionic chromatography (Dionex Ion Chromatograph System 2000) after appropriate dilutions. Fe, Mn, Cu, Zn, Sr, Li, and Rb were measured by flame atomic absorption spectrometry using standard additions (AAnalyst, Perkin Elmer Inc.). Aliquots for silica determination were immediately diluted 100- to 200-fold and analysed by the silicomolybdate automatic colorimetric method [42, 43].
3.3. Organic Geochemistry. Total Organic Carbon (TOC) was measured using a multi N/C 3100 (Analytik Jena AG, Germany). Samples were acidified online with HCl and then purged with [O.sub.2] to remove inorganic carbon (IC). A TIC control analysis was performed and followed by three TOC measurements on each sample.
Acetate and formate concentrations were determined using a Dionex ICS-2000 Reagent-Free Ion Chromatography System equipped with an AS50 autosampler (Dionex Camberley, UK). Chromatographic separation was conducted using two Ionpac AS15 columns in series at 30[degrees]C and the determination of species was carried out using an Anion Self-Regenerating Suppressor (ASRS 300 4 mm) unit in combination with a DS6 heated conductivity cell (35[degrees] C). The gradient program was as follows: 6 mmol [L.sup.-1] KOH (43 min); increase from 27 mmol [L.sup.-1] KOH [min.sup.-1] to 60 mmol [L.sup.-1] (39 min); decrease from 54 mmol [L.sup.-1] KOH [min.sup.-1] to 6 mmol [L.sup.-1] (5 min).
SVOCs were extracted using Stir Bar Sorptive Extraction (SBSE). Basically any compound with a log Ko/w > 2.5 is recovered with a rate > 50% . The method was improved after Konn et al. . The entire content of the titanium syringe was transferred into a precombusted glass bottle and six 90 mL aliquots of the sample were poured into 100 mL precombusted glass vials. 10 mL of MeOH was added to avoid adsorption of the compounds onto the wall of the vials. Internal standards were added to the solutions in 2012 so that quantification could only be achieved in Fatu Kapa fluids. Extraction was performed in sealed vials with ultrainert septum crimps, at 300 rpm and using 48 [micro]L PDMS Twisters[R] (Gerstel GmbH). We focused on a selection of chemical groups that had previously been described as hydrothermally derived . To that respect, pairs of aliquots were dedicated to analysis of n-alkanes, n-FAs, and both BTEXs and PAHs, respectively. Extraction kinetics experiments showed that chemical equilibrium was reached after 5 h of extraction for n-alkanes, 4 h for PAHs and 14 h for n-FAs (Konn, unpublished results). Twisters were then removed, rinsed with MQ water, dried, and stored at +4[degrees]C until analyses by Thermal Desorption-Gas Chromatography-Mass Spectrometry (TDGC-MS) . Analytical parameters were adjusted for each group of compounds (Table 1).
For each batch of conditioned Twisters, one was spared, stored at +4[degrees]C, and analysed in the same run as the other Twisters. This dry blank aimed at showing any contamination that could have occurred during conditioning, storage, and transport. MQ water samples were prepared and extracted on board as regular hydrothermal samples to check if any contaminations could have occurred during the sample preparation step. Deep-sea water was also collected, processed, and analysed, using the same titanium syringes and according to the same protocols as for hydrothermal fluid samples, and thus constitute the reference blank experiment.
Calibration was achieved using a commercial standard solution of BTEXs and 3 custom standard solutions of [C.sub.9]-[C.sub.20] n-alkanes, [C.sub.6]-[C.sub.18] n-FAs, and PAHs containing naphthalene (N), Acenaphtene (A), Fluorene (F), Phenanthrene (Ph), Anthracene (An), Fluoranthene (Fl), and pyrene (Py) (LGC Standards, LGC Ltd.). Deuterated n-alkanes ([C.sub.10][D.sub.22] and [C.sub.14][D.sub.34]), methyl esters ([C.sub.9][H.sub.18][O.sub.2] and [C.sub.15][H.sub.30][O.sub.2]), and deuterated PAHs (naphthalene-D8, Biphenyl-D8, and Phenanthrene-D10) were used as internal standards (IS). Calibration curves (Concentration (analyte)/Concentration (IS) versus Area (analyte)/Area (IS)) were obtained using at least five concentration levels that were replicated 3 times (Table 2). Although the correlation coefficient of the linear regressions was satisfactory for all compounds, the significance and lack of fit of the model were checked by statistical tests before validation. A series of Student, Barlett, Chi-square, and Fisher tests was run for each individual compound using the Lumiere software. The best fitting model was then chosen for each case and confidence intervals were calculated.
Altogether 35 hot fluid samples were collected in the study area from 8 different sites: Kulo Lasi caldera (6), on the one hand, and Stephanie (7), Carla (4), [Idef.sup.X] (4), [Obel.sup.X] (3), [Aster.sup.X] (1), Fati Ufu (6), and Tutafi (4), on the other hand, all located in the Fatu Kapa area (Figure 1). The Kulo Lasi smokers occurred at ~1500m depth on recent lava flows and consisted in a multitude of short (~25 cm) and narrow (~3-5 cm) diameter anhydrite chimneys containing a small percentage of sphalerite (ZnS), chalcopyrite (CuFe[S.sub.2]), isocubanite (Cu[Fe.sub.2][S.sub.3]), pyrrhotite ([Fe.sub.1-x]S), and pyrite (Fe[S.sub.2]) (Figure 2). The temperature was consistently about 343[degrees]C and the pH approached 2.2-2.3 (Table 3). In the Fatu Kapa area we could distinguish two types of hydrothermal environments at 1550-1650 m depth. Translucent 270-290[degrees]C fluids associated with anhydrite chimneys (up to 25 m tall and 2.5 m in diameter) characterised Stephanie, Carla, [Idef.sup.X], [Obel.sup.X], and [Aster.sup.X] sites, while >300[degrees]C milky to grey fluids associated with sulphide chimneys were characteristic of the southwest region including Fati Ufu and Tutafi sites (Figure 3, Table 3).
4.1. Gas. Concentrations of gases in all fluids as well as stable isotopes data are compiled in Table 4. Samples recovered from Kulo Lasi were extremely poor in C[H.sub.4] (<0.01 mM) but contained the series of [C.sub.2]-[C.sub.5] hydrocarbons. Samples from Fatu Kapa had higher concentration of C[H.sub.4] (0.05-0.235 mM) but only n-pentane (0.5-3.2 [micro]M) could be detected and quantified in terms of longer hydrocarbons. One sample from Kulo Lasi was found to be extremely rich in [H.sub.2] with nearly 20 mM while the others ranged from 1 to 6 mM and were below 0.05 mM at Fatu Kapa. [H.sub.2]S was highly variable between the 3 sampled chimneys at Kulo Lasi (0.39, 1.66, and 5.05 mM) while it was found rather homogeneous at Fatu Kapa with values around 1mM. C[O.sub.2] concentrations were more elevated at Fatu Kapa (4.5-29 mM) compared to Kulo Lasi (1-5 mM).
Helium isotope ratios were in the range 70-9.9 Ra over the Fatu Kapa area, in agreement with plume data . They could not be measured at Kulo Lasi unfortunately. Carbon isotopes ratios were around -5 [per thousand] for C[O.sub.2] at Fatu Kapa whereas at Kulo Lasi the ratio showed very different results ranging from -0.2 to -4.1 [per thousand]. As for methane, [delta][sup.13]C were slightly lower at Kulo Lasi (~-28 [per thousand]) versus Fatu Kapa (~-23 [per thousand]) and [delta]D was about -110 [per thousand] in all samples from Fatu Kapa. [delta]D (C[H.sub.4]) could not be measured in the Kulo Lasi fluids because of the too low concentrations of C[H.sub.4]. Carbon isotope ratios of longer hydrocarbons were in the -27 to -22 [per thousand] at both vent fields. To be noted one sample from Fati Ufu in the Fatu Kapa area showed remarkably lower isotopic ratios with [delta][sup.13]C (C[O.sub.2]) = -2.3 [per thousand], [delta][sup.13]C (C[H.sub.4]) = -6.1 [per thousand] and [delta]D (C[H.sub.4]) = -93 [per thousand]. We do not have any explanation for this but do not have any reasons either to consider it as an outlier.
4.2. Major and Minor Elements. Major and minor elements measurements data are compiled in Table 3. Fluids from Fatu Kapa all exhibited a higher salinity than seawater up to 4.6 wt% NaCl whereas at Kulo Lasi fluids with both lower (2.8 wt% NaCl) and higher (4.3 wt% NaCl) salinity were sampled. Mg and S[O.sub.4] concentrations tend to be zero in the purest samples at Fatu Kapa. But, the purest fluids from Kulo Lasi showed significant levels of Mg and S[O.sub.4], associated with an extremely acidic pH (<2.5) and a high T (343 [degrees]C). Although we cannot totally discard that some mixing with seawater occurred, endmember concentrations of the Kulo Lasi fluids were then estimated to be close to the purest fluids sampled whereas they were obtained from mixing lines at Fatu Kapa assuming Mg zero (Table 5).
Fluids from Fatu Kapa were enriched compared to seawater in alkali, alkaline Earth, and transition metals as well as in strontium, bromide, and silica. Conversely, the fluids from Kulo Lasi exhibited a much more complex pattern. They were all highly enriched in transition metals and silica compared to seawater and fluids from Fatu Kapa (e.g., Fe up to ~10 mM). The enrichment versus seawater in alkali metals was not as striking as for Fatu Kapa fluids. As for the alkaline Earth metals, the amount of Ca was identical to seawater and fluids were depleted in Sr compared to seawater. Finally, both depletion and enrichment in Br were observed in the fluids from Kulo Lasi.
4.3. Organic Geochemistry. First of all, we would like to mention that because solubility of organic compounds decreases with T and because samples were processed at room temperature, the measured concentrations are probably lower than in situ concentrations. Moreover, it is very likely that a portion of the OM was adsorbed on small particles in the fluids which are not taken into account using our extraction and analytical techniques. As a result, the concentrations we report here probably represent lower estimates of in situ concentrations. However, since in situ measurement techniques are not available yet, these values are the best estimates we can obtain. Note that they also are the first to be published for SVOCs.
Formate and acetate reached 16.3 and 15.5 [micro]M, respectively, and covaried with Mg in the Kulo Lasi fluids (Figure 4). Concentrations of formate and acetate were significantly higher in the Fatu Kapa area but no correlation with Mg could be observed. Nevertheless, the purest fluids usually showed the highest concentrations. Formate reached 68 ppb at Stephanie and 722 ppb at Fati Ufu whereas it could not be detected at [Idef.sup.X] and Tutafi and was not measured at Carla. Acetate was detected in all analysed samples and concentrations were an order of magnitude higher than the ones of formate (543-2309 ppb) (Table 6).
Heavier extractable organic compounds were not detected in the dry control experiment and only a few were detectable but below limit of quantification (LOQ) in the MQ water blank experiment (Table 6). This showed that sample preparation and storage could be considered as contamination-free steps. The levels of heavier extractable organic compounds appeared rather high in the reference water at Fatu Kapa certainly because of the overall spread hydrothermal discharges and diffuse venting in the region  (Table 6, Figure 5). This sample was indeed taken mid-way between [Obel.sup.X] and [Aster.sup.X] fields at about 20 m above the seafloor. As a consequence, it is difficult to assess possible contamination originating from sampling device or seawater contribution in the present case. However, earlier studies have shown that they generally did not represent major sources of contamination as for the studied compounds [27, 37]. Nevertheless, in comparison to deep-sea water both the qualitative (Kulo Lasi) and quantitative (Fatu Kapa) data obtained suggested enrichment of the fluids in hydrothermally derived compounds, namely, n-alkanes ([C.sub.9]-[C.sub.12]), n-FAs ([C.sub.9], [C.sub.12], [C.sub.14]-[C.sub.18]), and PAHs (fluorene, phenanthrene, pyrene) (; Table 6, Figures 5 and 6). Such enrichment was unclear for >[C.sub.12] n-alkanes; [C.sub.10], [C.sub.11], [C.sub.13] n-FAs; BTEXs; naphthalene, acenaphthene, and fluoranthene because of their very low concentration and/or the measurement uncertainty.
Differences in concentrations seemed to exist among the vents over the Fatu Kapa area. Fluids from the Stephanie vent field had concentrations in hydrocarbons equal or below the reference water sample whereas they were clearly enriched in [C.sub.9], [C.sub.12], [C.sub.14]-[C.sub.18] n-FAs. The Carla fluids were slightly enriched in [C.sub.9]-[C.sub.12] n-alkanes and showed the highest concentrations in PAHs. Fluids from [Idef.sup.X], Fati Ufu, and Tutafi shared some similarities: a strong enrichment in decane and undecane, alike concentrations in PAHs, and the presence of significant amounts of xylene. However, fluids expelled at the Tutafi vent appeared the most enriched in [C.sub.9]-[C.sub.11] n-alkanes and xylenes. In terms of fatty acids and considering the analytical error, the 5 vents showed consistent concentrations with [C.sub.9], [C.sub.16], and [C.sub.18] being major. Note that fluids from Fati Ufu seemed depleted in [C.sub.17] and [C.sub.18].
Generally we did not observe strong linear correlation between the concentration of individual compounds and Mg. Nonetheless, these relations showed that both enrichment and depletion of organic compounds seemed to occur in hydrothermal fluids versus deep-sea water.
The elemental and gas composition of hydrothermal fluids is mainly affected by water/rock interactions and thus the nature of the host rocks, phase separation, magmatic fluid contribution, conductive cooling, and seawater mixing in local recharge zones . In the following discussion we attempt to unravel the occurrence of these various processes both at Kulo Lasi and at Fatu Kapa. Much less is known on processes that control organic geochemistry and are therefore discussed here as well as some implications of the presence of organic compounds in hydrothermal fluids. Implications related to the composition of the fluids are dependent on fluxes; therefore, we give here an attempt to provide order of magnitude estimates of heat and mass fluxes.
5.1. Plume-Fluids Relations. The geochemistry and dynamics of the plumes over the Wallis and Futuna region have been studied elsewhere . The Kulo Lasi plume has been proposed to be the result of both high-T and diffuse venting from multiple vents located both on the floor and on the wall of the caldera. Consistently, both types of venting have been observed . Helium, nephelometry, and Mn profiles recorded above the northern sampling area showed constant elevated concentrations in the 300 masf and were assumed to be the results of diffuse venting. Our results show that they are obviously the result of the numerous small black smokers observed on the seafloor (Figure 2). The methane concentration in the sampled fluids was extremely low which cannot account for the elevated concentration of C[H.sub.4] in the water column reported by Konn et al. . The strong difference in the C[H.sub.4]/Mn ratios between the plume (0.7-4.5) and the sampled fluids (0.001-0.01) is another line of evidence that the methane plume has another origin compared to hydrothermal fluids and likely come from degassing of the lava flows as suggested by the authors. Although other fluid discharges likely remain undiscovered, this is consistent with a past eruption and accumulation of the water mass in the caldera .
A great diversity of the fluid compositions was expected from the geological settings and the water column survey and was indeed confirmed by the mixing lines that point to as many endmembers as sampled areas (Figure S1). C[H.sub.4]/TDM ratios also differed among the vents but it was not due to sole C[H.sub.4] concentration variations as suggested earlier (Table 5) . Finally, the very weak nephelometry of the Fatu Kapa plume is likely best explained by the low metal contents of the fluids.
5.2. Reaction Zone Depth. The solubility of Quartz in hydrothermal fluids has been studied by different authors (e.g., ). According to these works silica concentration in the fluid may be used to estimate the depth of the reaction zone. The silica concentration measured in the Kulo Lasi and Fatu Kapa fluids indicates a hydrothermal reaction zone at seafloor or in the water column (Figure S2). Both observations suggest that, in this area, fluids are not in equilibria with Quartz at the pressure and temperature of the fluid emission. And this prevents using Si as a geothermometer to determine the depth of the reaction zone.
All fluids at Fatu Kapa were indeed highly depleted in Si with respect to the Quartz saturation curve at 170 bar, 300[degrees]C (Si ~12 mM in Figure [S.sub.2]). A higher temperature in the reaction zone (>350[degrees]C at 200 bar) may explain a lower Si concentration in the fluid at equilibrium as Quartz solubility decreases (Figure [S.sub.2]). The dispersion of a great number of vent fields over a large area of recent lava flows may be due to complex fluid pathways that favour conductive cooling of the fluid and subsurface loss of silica before venting on the seafloor. Consistently, amorphous silica was common in the seafloor deposits at Fatu Kapa where opal was abundant as a late mineral in sulphides and as silica crusts (slabs) at the surface of the deposits . In conclusion, this would indicate a fairly shallow reaction zone at Fatu Kapa (a few 100 mbsf) in agreement with the geological settings and the possible occurrence of dikes.
5.3. Chlorinity. Phase separation is often accounted for salinity deviation in hydrothermal fluids versus seawater [47,48]. Phase separation is of great importance in metal transportation and ore-forming processes, for example, [24, 49-51]. It also implies that seawater experiences dramatic changes in its physical and chemical properties as it reaches the super- or subcritical state. In particular, strong modification of the density and ionic strength of seawater enables unconventional chemical reactions, hence a likely importance in hydrothermal organic geochemistry, for example, . The measured P and T of the Kulo Lasi fluids are almost on the critical curve of seawater meaning that liquid and vapor phase may coexist at Kulo Lasi. An adiabatic decompression of supercritical seawater (initial fluid and equivalent to 3.2 wt% NaCl) as it rises towards the seafloor would cause it to separate, at about 320-350 bar and 415-420[degrees]C, into two phases having the NaCl percentages observed at Kulo Lasi (Figure [S.sub.3]) [53, 54].
Similarly, the excess salinity of the Fatu Kapa fluids (9 to 41%) could be explained by phase separation and is supported by the Br/Cl ratios which significantly differed from seawater [45, 55]. Since we have not sampled any Cl-depleted fluids we may infer that phase separation may have occurred in the past and that only the brine phase was venting at the time of the cruise. Alternatively water-rock reactions could represent a significant Cl source to the fluids . Indeed, the felsic lavas collected in the Fatu Kapa area contained up to 10 times more Cl than MORB (Aurelien Jeanvoine, personal communication).
5.4. Water-Rock Reactions. Generally, fluids from Kulo Lasi and Fatu Kapa were not typical of back-arc settings but shared similarities with ridge, arc, and back-arc settings fluid signatures . The Kulo Lasi fluids have unusually high concentrations of Mg (24.6 to 34.9 mM) and S[O.sub.4] (6.2 to 12.0 mM) at low pH (2.24 to 3.32) and high T (338-343[degrees]C) which indicate that significant seawater mixing at subsurface or during sampling is rather unlikely. In back-arc context, the occurrence of Mg and S[O.sub.4] in endmember fluids can be explained by a magmatic fluid input as observed at the Desmos [5, 57], Rota 1 and Brother sites [58, 59]. Magmatic-derived S[O.sub.2] would disproportionate according to reaction (1) at temperatures measured at Kulo Lasi (e.g., [5, 60]). This is consistent with widespread occurrences of native sulfur on fresh lava near the active vents  as well as the low pH of the fluids.
3S[O.sub.2] (aq) + 2[H.sub.2]O = [S.sup.0] (s) + 4[H.sup.+] + 2S[O.sub.4] (1)
Yet C[O.sub.2] concentrations are low and the Na: K: Mg ratios are strongly different to seawater. The latter suggests a contribution of Mg by dissolution of magnesium silicates . Besides, the high Li and Rb concentrations and the presence of recent lava injected in the caldera point to water/fresh hot volcanic rocks interactions. Notably, such interactions are capable of producing the extremely high concentration of [H.sub.2] measured in the [Cl.sup.-]depleted sample and thus the very unusual [H.sub.2]/C[H.sub.4] observed  (Figure S4). High concentrations of metals are consistent with the highly acidic nature of the fluids coupled with high [H.sub.2]/[H.sub.2]S ratios [62, 63].
The relatively mild pH, [sup.3]He/C[O.sub.2], and R/Ra ratios of the Fatu Kapa fluids are diagnostic of the occurrence of seawater/MORB interactions [64-66] (Figure S5). Consistently, the geochemistry of the Fatu Kapa fluids was very similar to the Vienna Woods ones whose composition is mainly the result of interactions with basalts [3, 4]. Yet metal concentrations were lower at Fatu Kapa while Ca, K, and Rb were higher and Li is similar. Plausible explanations for the extremely low metal concentrations observed in the Fatu Kapa fluids are conductive cooling; water/metal-poor rocks interactions; subsurface metal trapping under silica and barite slabs . Given the wide variety of lithologies sampled in the area, fluid compositions are likely the results of interactions with a wide range of rock source chemistries. To that respect, the composition of the local lavas that are characteristic of andesite, trachy-andesite, dacite, and trachy-dacite probably best explains the enrichment in Ca and in the mobile alkali metals K and Rb.
5.5. What Controls Organic Geochemistry? The origin of hydrocarbon gases and SVOCs in natural systems including hydrothermal systems has been the focus of many studies since the abiotic origin of some hydrocarbons was postulated ([67, 68] for a review). Both field and experimental studies have tried to unravel the origin of hydrocarbons making use of stable isotopes (e.g., reviews of [34, 35]). Although there are strong discrepancies among studies, the variation of [delta][sup.13]C with the carbon number may be a reasonable indicator of the origin. The trend observed in the [Cl.sup.-]depleted sample of Kulo Lasi was very similar to the ones attributed to an abiogenic origin in the Precambrian shields or in the Lost City hydrothermal field [69,70]. The Kulo Lasi [Cl.sup.-]rich sample exhibited a pattern that has been observed in several Fischer-Tropsch type (FTT) experiments . The strong positive or negative fractionation between [C.sub.1] and [C.sub.2] observed in the hot fluids of Kulo Lasi is likely due to chain initiation . Conversely, the low-T (135[degrees] C) sample that was collected in a beehive-type smoker covered with bacterial mats showed a regular positive trend which has been proposed to be diagnostic of a thermogenic origin. Although we concede that the abiogenic origin of [C.sub.2+] hydrocarbon gases in the Kulo Lasi field will need more investigation, methane is clearly at the border of abiogenic and thermogenic domains both at Kulo Lasi and at Fatu Kapa with [delta][sup.13]C values ranging from -29 to -6.1 [per thousand] ( and Figure 7). Carbon isotopes of C[H.sub.4] and C[O.sub.2] suggest that methane underwent oxidation, possibly by bacteria, at both sites and may explain the extremely low concentrations observed (Figure 8 in ). Consistently and according to thermodynamic calculations, methanogenesis should be limited under the P, T, and redox conditions present at the Futuna sites and C[H.sub.4] consumption might be prevalent .
By contrast, carbon isotopes have not appeared to be useful up to date in determining the origin of heavier organic compounds . Several processes are likely to occur simultaneously and to use several C sources, resulting in a nondiagnostic bulk [delta][sup.13]C signature. Several experimental and theoretical studies indicate that a range of organic compounds including linear alkanes and FAs could form and persist in natural hydrothermal systems (e.g., [31-35]). However, according to the calculated f[H.sub.2] at P and T of the study sites, the redox conditions are likely buffered by Hematite-Magnetite (HM) or an even more oxidizing mineral assemblage which appear less favourable for abiotic synthesis than Pyrite-Pyrrhotite-Magnetite, Fayalite-Magnetite-Quartz, or ultramafic rocks assemblages [27,32,33] (Table 4). The occurrence of organic compounds in our fluids must thus be attributed to a great part to other processes. Microbial production and thermal degradation of microorganisms, OM detritus, and/or refractory dissolved OM represent good candidates to produce soluble organic compounds. PAHs are indeed common products of pyrolysis of OM [26, 75, 76]. Long chained fatty acids are major constituent of organisms and their presence in the Futuna fluids could be easily associated with thermal degradation of biomass or OM [26, 77]. Yet the distribution of the compounds found in the fluids does not match a simple process of OM degradation. Only >[C.sub.13] n-FAs occurred in sediments with [C.sub.16] being the most abundant (Figure S6). However, similar to our samples, both odd and even carbon number n-FAs were observed in the [C.sub.14]-[C.sub.20] range with odd FAs being less abundant. Petroleum exhibits nearly equal levels of [C.sub.14]-[C.sub.20] n-FAs. Only the even series has been reported in both massive sulphide deposits (MSD) and hydrothermal mussels with [C.sub.16] being the most abundant. Short chain FAs (<[C.sub.13]) have onlybeen reported in Lost City fluids but here again only the even series occurred. In any case [C.sub.9] was reported whereas it was nearly the most abundant in our fluids. Abiotic processes may still be considered as nonanoic acid could be synthesized from C[O.sub.2] and [H.sub.2] , nonane , or undecane . As a difference the presence of [C.sub.16] and [C.sub.18] n-FAs in significant amount in the fluids from Fatu Kapa may represent a direct microbial contribution. The distribution observed in the Fatu Kapa fluids likely reflects the occurrence of several concomitant processes possibly including production reactions (abiotic and thermogenic) and consumption mechanisms (adsorption and complexation).
Nonvolatile n-alkanes are usually associated with lower T processes such as in oil fields or at the Middle Valley hydrothermal vent field . In the Guaymas basin, where n-alkane-rich sediment samples have been reported, it is less clear what temperature they were exposed to. However and as far as we understood high temperatures were rather associated with absence of n-alkanes and presence of PAHs consistently with high-temperature OM pyrolysis [26,81,82]. Pyrolytic processes resulted in the presence of light hydrocarbon gases with an exception of some high T (>200[degrees]C) fluids containing [C.sub.9] and [C.sub.10] n-alkanes. n-Alkanes also occur in solids from unsedimented hydrothermal vent fields ( and references therein). Notably, the n-alkanes distribution in our fluids does not resemble any aspects neither the ones resulting of low-T processes nor the ones created by high-T FTT reactions [83, 84] (Figure S7). [C.sub.10]-[C.sub.20] n-alkanes usually occur in equivalent amounts in petroleum or show a consistent decrease with molecular weight. Experimental FTT reactions produced consistent increasing concentrations from [C.sub.9] to [C.sub.12] and then consistent decreasing concentrations to [C.sub.20]. Similar patterns are also associated with the kerosene fraction of petroleum . Distribution patterns in hydrothermal solids are difficult to picture as usually only chromatograms are provided in the studies, for example, , but they largely differ by the simple fact that <[C.sub.14] alkanes were not detected in most cases as in sediments from various locations . The smaller alkanes may well be preferentially entrained in fluid circulation but they are more likely the result of other processes, especially high-temperature ones, and including abiotic reactions. Note that the latter should not be reduced to sole FTT reactions because supercritical water is a fabulous medium for unconventional reactions [88-90].
Formate and acetate have been given more attention in both laboratory [91-93] and field hydrothermal studies [28, 29] as these small molecules are likely to prevail according to thermodynamic studies (e.g., [31-33]). Where usually formate dominates, acetate was found to be more abundant in fluids from Fatu Kapa. According to Shock studies, at 280-300[degrees]C, formic acid concentrations should not be much higher than acetic acid, but this is not enough to explain our "reverse" concentrations. And especially it is not consistent with higher amounts in the 300[degrees]C fluids. A ratio close to 1 was observed at Kulo Lasi which may indicate that different production/consumption processes occur. Also the concentrations of the formate and acetate plotted on a line versus Mg which suggest that the fate of these volatile fatty acids at Kulo Lasi is controlled by simple mixing; that is there would be no consumption/production when fluid mixes with seawater (Figure 4). The deep-seawater concentrations were high compared to what is usually reported in the literature which was most likely due to plume contribution [27, 28]. This supports the simple mixing model hypothesis and is consistent with the near absence of organisms around those chimneys.
5.6. Organic Compounds: Implications for Biology, Mineral Resources, and C Cycling. The idea that life could have originated in hydrothermal systems from abiotic reactions was postulated in the late 70s . However, the question of the origin of organic compounds in hydrothermal systems has remained ever since they were evidenced in natural environments . On the one hand, a biogenic or thermogenic origin seems most likely for most compounds investigated so far; on the other hand, one cannot exclude that some of the formate and aliphatic hydrocarbons form abiotically [13, 26-28, 30, 96]. As detailed in the previous section, our results are consistent with a mix of origin although abiotic synthesis likely occurs to a far smaller extent than other processes that would overprint an abiotic signature.
Upon the hot topic of the origin of life, the mere presence of organic compounds is highly important for the fauna at the local and regional scales. It is well established that VFAs constitute a significant food source for some microorganisms and thus help sustaining hydrothermal ecosystems [97-100]. Besides, some bacteria have proven to be capable of using naphthalene  and tubeworms, hydrocarbons .
Organics can form complexes with metals [20, 21]. This greatly improves the dispersion of metals in the ocean and prevents them from precipitation as sulphides or oxyhydroxydes [23, 103]. Notably fatty acids are efficient ligands that play a major role in making metals bioavailable as well as in transporting them both through the upper crust ( and references therein) and through the water column in the plume [11, 104-106]. In addition, they have been shown to be involved in growth/dissolution processes of some minerals [19, 107]. For these reasons, they are of particular importance in ore-forming processes. Hydrocarbons which are weaker ligands would react with sulfates to generate bisulfide (H[S.sup.-]), which in turn would easily react with metal chlorides to form metal sulphides according to the following mass balance equations:
3S[O.sub.4.sup.2-] + 3[H.sup.+] + 4R-C[H.sub.3]
[right arrow] 4R-C[O.sub.2]H + H[S.sup.-] + 4[H.sub.2]O (2)
H[S.sup.-] + Me[Cl.sub.2] [right arrow] MeS + [H.sup.+] + 2[Cl.sup.-] (3)
where R is a carbonated chain, either aliphatic or aromatic, and represents OM . To that respect hydrocarbons are likely to be involved in depositional processes of metals. Notably associations of aliphatic and aromatic hydrocarbons with mineral deposits have also been observed on the EPR  and in sulphide sedimentary deposits on land .
5.7. Fluxes: Importance of Back-Arc Hydrothermal Systems to the Ocean Geochemistry. Hydrothermal input to the ocean via plumes has long been neglected but recent results of the GEOTRACES program clearly show its importance in terms of metals and trace elements transportation and implications for ocean biogeochemistry [13, 110-113]. While it is now well established that MOR hydrothermal discharge has a large impact on the global ocean chemistry and element cycles, the relative impact of hydrothermal activity from other hydrothermal settings has not been established. The extensive hydrothermal activity reported in the Wallis and Futuna region suggests that back-arc system hydrothermalism may be of much greater importance than previously anticipated [7, 114]. Estimation of hydrothermal fluxes is generally challenging and very few data are available in the literature [115-118]. Therefore we believe that any kind of estimation, even orders of magnitudes are of importance to make advances in this field. We propose to combine two different approaches based on geophysical data and video recordings (see here), respectively, to propose such estimates with some confidence.
5.7.1. Estimation Using Geophysics. We can make an order of magnitude estimate of the heat flux from the different hydrothermally active areas based on the physical characteristics of the plumes. Marshall and coworkers [119-121] have proposed a scaling relationship between the heat flux at an interface, Hf, the ambient buoyancy frequency (N) in the surroundings of the plume, the characteristic size ([R.sub.s]) of the heat transfer region, and the equilibrium height (or depth; h) reached by the plume, as
Hf = ([rho] x Cp)/(g x [alpha] x [R.sub.s]) x [(N x h/5).sup.3], (4)
where [rho] is seawater density (1030 kg x [m.sup.-3]), Cp is heat capacity of seawater (~4000 J x [kg.sup.-1] x [K.sup.-1]), and g is gravitational acceleration (9.81 m x [s.sup.-2]), and [alpha] is the thermal expansion coefficient of seawater ([10.sup.-4] [K.sup.-1]). The ambient buoyancy frequency (N) can be estimated to be between 0.001 and 0.002 [s.sup.-1] from CTD profiles in the area using a routine in the UNESCO Sea Water Library described by Jackett and Mcdougall . The radius ([R.sub.s]) of the Kulo Lasi caldera is 2500 m and the plume rose in average about 200 m above seafloor (top layer boundary) . For order of magnitude estimates, the ~130 [km.sup.2] Fatu Kapa area can be approximated by a disk of radius 6400 m, with a similar plume height. Introducing these numbers in (4) leads to heat flux estimates ranging between 100 and 800 W x [m.sup.-2] for the Kulo Lasi caldera and 50 and 400 W x [m.sup.-2] for the Fatu Kapa area, which is greatly dependent on the value for buoyancy frequency. While these estimates scale proportionally with the area considered to be hydrothermally active, they integrate the sources within the area which do not demand that the whole area be active. We estimate that total heat inputs are in the 2-16 GW for the Kulo Lasi caldera and 5-40 GW for the Fatu Kapa areas.
5.7.2. Estimation Based on Video Postprocessing. Video recordings could be used to estimate fluid velocities of the Carla and [Obel.sup.X] chimneys and of a few smokers at Kulo Lasi using for instance the Typhoon algorithm  (Figures S8-S11). This optical flow method recovers the (2D) fluid flow from the apparent displacements, in an image sequence, of tracers advected by the flow. Here, the plume acts as the tracer. Compensation for the camera and vehicle motion and parallax correction were not possible, so the investigated video sequences where chosen according to (i) the overall stability of the camera and vehicle and (ii) the plume being as perpendicular to the camera as possible. The relevant lengths scales (image spatial resolution and diameter of the chimneys) had to be estimated from known object sizes in the same ground, typically shrimps. External diameters of the chimney were used for calculation as any estimation of the internal diameter on video recordings would be too speculative. Note that (i) chimney samples taken at Kulo Lasi exhibited similar internal and external diameters; (ii) the large anhydrite chimneys (e.g., [Obel.sup.X], Carla) at Fatu Kapa did not seem to have any central conduit but rather exhibited a sponge-like structure leaking fluid at a high velocity from the entire volume. As a result, we believe the overestimation resulting from this assumption to be limited. Finally, the observed flow velocity is assumed to be constant across the jet section. Given all these limitations and assumptions, the resulting fluxes values should be taken as an indication of their order of magnitude.
The fluid velocity was estimated to be on average 0.05, 0.15, and 1 m [s.sup.-1] for Kulo Lasi, Carla, and [Obel.sup.X], respectively In terms of heat fluxes, Carla (diameter ca. 70 cm) would generate ~6 MW while [Obel.sup.X] (diameter ca. 250 cm) would produce ~5.7 GW, respectively. Associated mass fluxes would be 54 L [s.sup.-1] and 5 [m.sup.3] [s.sup.-1] which means, for instance, that the single [Obel.sup.X] chimney could generate an input of 2.6 x 107 moly-1 C[H.sub.4] to the ocean. Comparatively, estimation of the total efflux of methane from serpentinisation ranges from 15 to 84 x [10.sup.9] mol [y.sup.-1] including 9 x [10.sup.9] mol [y.sup.-1] for the sole slow spreading ridges. Similarly, the Carla chimney would release about 5.7 x [10.sup.3] mol [y.sup.-1] of dodecane that may help forming 1.4 mol [y.sup.-1] of metal sulphides (see Section 5.6). Cumulative observations during the dives brought to a total of 220 smokers of various sizes (~5 cm to ~2.5 m in diameter) and apparent flows (strong, medium, slow). We assigned the strong, medium, and slow flows observed to the velocities of [Obel.sup.X], Carla, and Kulo Lasi, respectively. At Kulo Lasi about 100 smokers were counted during the Nautile dives and all appeared very similar in diameter (~3 cm) and fluid flow (0.05). Keeping in mind these uncertainties, an order of magnitude of the heat and mass fluxes generated by hot smokers at Fatu Kapa are estimated to be 6.8 GW and 6 [m.sup.3] [s.sup.-1] for the Fatu Kapa area versus 9 MW and 6 L [s.sup.-1] for the Kulo Lasi caldera. This means, for example, that the total Fe flux from hot fluids emanating from the caldera would be up to 1.9 x [10.sup.6] mol [y.sup.-1] versus recent estimations of the global hydrothermal iron input that are about 109 mol [y.sup.-1] [112, 124]. The average nonanoic acid concentration in Fatu Kapa purest fluids is 7.25 ppb, which would result in 1.4 x [10.sup.6] mol [y.sup.-1] released in the ocean by the Fatu Kapa hot smokers. The carboxylic acid functional group of fatty acids makes them good potential ligands to form coordination complexes with iron, which stabilises iron in the plume in its reduced form [103, 125]. Hence, the example of nonanoic acid suggests that fatty acids could largely contribute to iron stabilisation.
However, the high-temperature fluxes calculated above failed to include heat fluxes from diffusive venting, which was largely present in both areas and is thought to be an important part of the global hydrothermal heat flux (up to 98%) . The surface of the diffusive areas was also assessed on the videos. However, because the velocity of diffusive fluids could not be estimated using Typhoon, we assumed hydrothermal waters are exiting the seafloor at the minimum velocity reported for low temperature flow (0.04 m [s.sup.-1]) . The cumulative surface of diffusive areas with a typical temperature of 10[degrees]C reached 100 [m.sup.2] at Kulo Lasi and 2885 [m.sup.2] at Fatu Kapa. In addition, a particular area of about 300 [m.sup.2] at Kulo Lasi consisted in hundreds of silica chimney diffusing a 40[degrees]C fluid . The resulting contribution of diffuse venting to the heat flux would be 2.14 GW and 5.3 GW at Kulo Lasi and Fatu Kapa, respectively. This brings the total heat flux estimates at 2.15 GW and 12 GW, respectively, which is consistent with the estimates obtained using the lower N value as well as the fact that only a small portion of the total surface of the sites was explored with the submersible.
5.7.3. Summary. According to these different estimates heat efflux at Kulo Lasi and Fatu Kapa are conservatively estimated to be at least for 1-2 GW and 5-10 GW, respectively; this estimate is based on the low N value, whereas using the higher N suggests a flux almost 10x higher. It seems highly likely that the Wallis and Futuna active areas combined with the 3 calderas to the East  have a heat flux of >10 GW. Vent fields on MOR have been reported to generate between 10 MW and 25 GW ([116, 117, 127, 128] and references therein) and the total hydrothermal heat flux at MORs is estimated to be about 1000 GW [129, 130]. This suggests that the presently discovered area might be of significant importance in the global budget and that back-arc hydrothermal activity contributes as much as MOR systems, and, possibly more, to the global ocean chemistry and cycles. Few estimates of hydrothermal heat flux have been published and the relative importance of heat, fluid, and geochemical hydrothermal fluxes from different environments will require studies designed to more accurately gauge these fluxes.
6. Concluding Remarks
The study of the geochemical characteristics of hydrothermal fluids from the Wallis and Futuna area confirmed the great potential of the region to generate a variety of fluid chemistries, as it was expected considering its particular geological context. This supports the idea that the hydrothermal contribution of back-arc environments is of great interest for the global ocean chemistry. Our order of magnitude estimates of fluxes suggest that back-arc hydrothermal activity contributes as much as MOR systems and possibly more. Notably the sole [Obel.sup.X] chimney could generate ~1 [per thousand] of the total hydrothermally derived C[H.sub.4]. The diversity observed in the Wallis and Futuna area also emphasizes that each new field presents its own characteristics and that exploration should continue. A huge number of sites remain to be discovered according to the newly published estimation of vent fields occurring on Earth .
A special focus was brought on organic geochemistry because of the few data available in modern hydrothermal systems despite the recent growing interest for oceanic OM. Concentrations of SVOCs are the first to be reported which will have implications in a wide range of questions and fields. Our results are relevant to the understanding of C cycling and complete the works by Hawkes and Rossel who demonstrated that DOM is recycled if not removed partially through hydrothermal systems but who could not identify compounds in DOM. Identification of organic molecules is especially needed to better understand organometallic chemistry at hydrothermal vents and thus utilisation by microbes, metal export, and ore-forming processes. The distribution patterns obtained revealed the occurrence of several processes controlling organic geochemistry and notably that one cannot exclude abiotic synthesis to occur in the study area but very likely to a so small extent that the signature would be overprinted.
This brings the idea that using natural concentrations to feed thermodynamic models of abiotic synthesis and/or guide the design of experimental work should enable making progress in unravelling the origin of organic compounds in hydrothermal systems. In addition, growing techniques as clumped isotopes  and position specific isotopes measurements  are available and should also help answering this question.
Conflicts of Interest
The authors declare that they have no conflicts of interest.
The 2010 and 2012 cruises to the French EEZ of Wallis and Futuna were financed through a public/private consortium of the French state, Ifremer, AAMP, and BRGM and industrial groups including Eramet, Technip, and Areva. The authors are very grateful to the ship crew and the ship captains JR. Glehen, P. Moimeaux, and R. Picard for running these three cruises with skills and professionalism. They acknowledge all the scientific parties of these cruises for their collaboration. They are also grateful to D. Pierre, C. Guerin, and A. Normand for processing bathymetric data on board and thank A.-S. Alix for providing the final maps. They are indebted to the physical oceanographers L. Marie and B. Le Cann who helped a lot with fluxes estimations and water mass physics. Finally, many thanks are due to P. Derian from the Fluminance team (Inria, Rennes, France) who postprocessed video recordings using Thyphoon for fluxes estimation.
Supplementary 1. S1: mixing lines used for calculation of the endmember composition of the Fatu Kapa fluids. S2: modified after Von Damm et al. . Plot of the molality of dissolved SiO2 in equilibrium with quartz in seawater versus temperature for isobars from 1500 to 1000 bar according to Von Damm et al. model. The Si most enriched fluid collected at Kulo Lasi is represented by the blue star. The red circle covers the range of Si concentrations and T encountered in fluids from the Fatu Kapa vent field. S3: modified after Bischoff and Pitzer . Stars stand for Kulo Lasi fluid phases characteristics. They nearly plot on the 150-bar isobar. The close-up of the 400[degrees]C, 300-bar region shows that seawater could produce the observed salinities at Kulo Lasi by phase separation at about 320-350 bar and 415-420[degrees]C. S4: modified after Kawagucci et al. . Plots of H2 concentration versus CH4 concentration in various hydrothermal fluids. The grey area represents values observed in a hydrothermal experiment using natural seafloor sediments. Values obtained for the Wallis and Futuna vent fields are reported: Kulo Lasi brine and condensed vapour phases are marked by the red square and the blue diamond, respectively, and the blue shaded area covers the range of values obtained in the Fatu Kapa field. S5: modified after Lupton et al. . (a) Plot summarizing 3He/4He ratio versus C/3He for various mantle provinces, including mid-ocean ridges (black-filled symbols), submarine arc volcanoes (blue), and sub aerial arc volcanoes (green). Values for the Fatu Kapa vent field are reported as orange diamonds. 3He/4He is expressed as R/Ra. Crosses indicate average values for MORBs and for subaerial arcs from. (b) Similar plot including values for hotspot volcanoes such as Loihi, Kilauea fumarole, Yellowstone Park gases, Reunion, and Fatu Kapa (orange diamonds). S6: distribution of linear fatty acids in various environments. Data are from  for Massive Sulphide Deposits (MSD);  for Lost City (LC) fluids;  for petroleum and recent and ancient sediments;  for 13[degrees]N mussels. S7: distribution of linear alkanes obtained by thermogenic maturation in various crude oil basins and abiotic Fischer-Tropsch type experiment . S11: time series of the estimated displacements corresponding to the video sequences shown in Figures S8, S9, and S10.
Supplementary 2. S8: example of a postprocessed video
sequence using the Typhoon algorithm to estimate displacements (instantaneous, left panel; averaged on 25 frames, right panel) on one of the small black smokers in the Kulo Lasi caldera.
Supplementary 3. S9: example of a postprocessed video sequence using the Typhoon algorithm to estimate displacements (instantaneous, left panel; averaged on 25 frames, right panel) at the base of the Carla chimney.
Supplementary 4. S10: example of a postprocessed video sequence using the Typhoon algorithm to estimate displacements (instantaneous, left panel; averaged on 25 frames, right panel) at the top of the massive [Obel.sup.X] chimney. S11: time series of the estimated displacements corresponding to the video sequences shown in Figures S8, S9, and S10.
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C. Konn (iD), (1) J. P. Donval, (1) V. Guyader, (1) E. Roussel, (2) E. Fourre, (3) P. Jean-Baptiste, (3) E. Pelleter, (1) J. L. Charlou, (1) and Y. Fouquet (1)
(1) Ifremer, Laboratoire des Cycles Geochimiques et Ressources, CS10070, 29280 Plouzane, France
(2) Ifremer, Laboratoire de Microbiologie des Environnements Extremes, CS10070, 29280 Plouzane, France
(3) LSCE, UMR 8212 CEA-CNRS-UVSQ, 91191 Gif-sur-Yvette, France
Correspondence should be addressed to C. Konn; email@example.com
Received 23 June 2017; Revised 31 October 2017; Accepted 17 December 2017; Published 11 March 2018
Academic Editor: Xing Ding
Caption: Figure 1: Bathymetric map of the study area. Close-ups of Fatu Kapa and Kulo Lasi are shown in boxes where sample positions are marked with red disks. Copyrights from Ifremer, FUTUNA 1, 2, and 3 cruises.
Caption: Figure 2: Photographs of sulphide chimneys and young lava flows observed on the floor of the Kulo Lasi caldera. Copyrights from Ifremer, FUTUNA 1 cruise.
Caption: Figure 3: (a) and (b) Photographs of anhydrite structures observed at Stephanie, Carla, [Idef.sup.X], [Aster.sup.X], and [Obel.sup.X] site. (c) Photographs of grey smokers associated with sulphides structures observed at Fati Ufu and Tutafi. Copyrights from Ifremer, FUTUNA 3 cruise.
Caption: Figure 4: Mixing lines of formate and acetate versus Mg for the Kulo Lasi fluids. Note that the reference deep-sea water sample (FU-PL05-TiG2 noted as SW here) was taken at 1150 m depth above the southern wall of the caldera (see Figure 1 for location and Table 3) and thus very likely within the plume . This would account for the unusual concentrations of formate and acetate detected.
Caption: Figure 5: Distribution of n-alkanes, n-fatty acids, mono-, and polyaromatic hydrocarbons (BTEX and PAH) in the purest fluids of the Stephanie, Carla, [Idef.sup.X], Fati Ufu, and Tutafi sites collected within the Fatu Kapa vent field. Because organic geochemistry does not seem to follow a simple mixing model, endmember concentrations cannot be calculated. To that respect composition of the purest fluids is presented and assumed to be close to endmembers composition. Note that quantitative results are not available for the Kulo Lasi fluids (see Figure 6 for chromato grams).
Caption: Figure 6: Only qualitative results could be obtained at Kulo Lasi. This figure presents a selection of representative chromatograms obtained for the Kulo Lasi fluid samples. For the sake of clarity, close-ups of a few peaks are shown to illustrate the enrichment of fluids (FU-PL06-TiG1 in red and FU-PL06-TiD3 in green) versus the reference deep-sea water (FU-PL05-TiG2 in blue).
Caption: Figure 7: Modified after Etiope and Sherwood Lollar . The isotopic composition of C[H.sub.4] in the Fatu Kapa fluids falls into the abiotic gas category but differs from the typical isotopic signature of C[H.sub.4] at Mid-Atlantic Ridge's vent fields.
Table 1: Main GC analytical parameters used for calibration and analyses of hydrothermal fluid samples. Each group of compounds (n-alkanes, BTEXs, PAHs, and n-fatty acids) was analysed using separate twisters. n-Alkanes Oven Initial T ([degrees]C) 40 Initial t (min) 1 ramp 40 to 320[degrees]C at 12[degrees]C/min Final T ([degrees] C) 320 Final t (min) 2 Injector T ([degrees]C) 250 BTEX & PAHs Oven Initial T ([degrees]C) 40 Initial t (min) 1 ramp 40 to 320[degrees]C at 12[degrees]C/min Final T ([degrees] C) 320 Final t (min) 2 Injector T ([degrees]C) 250 n-Fatty acids Oven Initial T ([degrees]C) 40 Initial t (min) 1 ramp 40 to 320[degrees]C at 20[degrees]C/min Final T ([degrees] C) 320 Final t (min) 2 Injector T ([degrees]C) 325 Table 2: Experimental conditions used for calibration curves. Linear regressions were performed on one order of magnitude concentration domain depending on the concentration range of the samples. n-Alkanes Concentration levels 0.5, 1, 2, 5, 10 ([micro]g x [L.sup.-1]) IS concentration 5 ([micro]g x [L.sup.-1]) BTEX & PAHs Concentration levels 0.05, 0.1, 0.25, 0.5,1, 2, 5,10 ([micro]g x [L.sup.-1]) IS concentration 5 ([micro]g x [L.sup.-1]) n-Fatty acids Concentration levels 0.25, 0.5, 1, 2, 5, 10 ([micro]g x [L.sup.-1]) IS concentration 10 ([micro]g x [L.sup.-1]) Table 3: Measured concentration of major and minor elements in hydrothermal fluids from the Kulo Lasi and Fatu Kapa vent fields. FUX-PLYY-TiDZ and FUX-PLYY-TiGZ are replicate samples taken in the same orifice, one after the other, but using 2 individual Ti syringes. T max (chimney) is the maximum T of the discharged fluid for the given chimney which was recorded by the T probe of the submarine before sampling. T max (sample) is the maximum T of the fluid entering the sampler recorded during sampling by the autonomous sensor that was coupled at the nozzle of the sampler. Sample name Zone Site IAPSO -- -- FU-PL-05-TiG2 Kulo Lasi South (out) FU-PL-05-TiG1 Kulo Lasi South (in) FU-PL-06-TiG4 Kulo Lasi North (in) FU-PL-06-TiD4 Kulo Lasi North (in) FU-PL-06-TiG3 Kulo Lasi North (in) FU-PL-06-TiD3 Kulo Lasi North (in) FU-PL-06-TiD1 Kulo Lasi North (in) FU-PL-06-TiG1 Kulo Lasi North (in) FU3-PL-03-TiD3 Fatu Kapa 20 masf FU3-PL-14-TiG2 Fatu Kapa 23 masf FU3-PL-04-TiD3 Fatu Kapa Stephanie FU3-PL-04-TiG3 Fatu Kapa Stephanie FU3-PL-08-TiD1 Fatu Kapa Stephanie FU3-PL-08-TiG1 Fatu Kapa Stephanie FU3-PL-08-TiD2 Fatu Kapa Stephanie FU3-PL-09-TiD2 Fatu Kapa Stephanie FU3-PL-09-TiG2 Fatu Kapa Stephanie FU3-PL-06-TiD1 Fatu Kapa Carla FU3-PL-06-TiG1 Fatu Kapa Carla FU3-PL-08-TiD3 Fatu Kapa Carla FU3-PL-08-TiG3 Fatu Kapa Carla FU3-PL-11-TiD3 Fatu Kapa [Idef.sup.X] FU3-PL-11-TiG3 Fatu Kapa [Idef.sup.X] FU3-PL-14-TiD1 Fatu Kapa [Idef.sup.X] FU3-PL-14-TiG1 Fatu Kapa [Idef.sup.X] FU3-PL-14-TiD2 Fatu Kapa [Obel.sup.X] FU3-PL-14-TiD3 Fatu Kapa [Obel.sup.X] FU3-PL-14-TiG3 Fatu Kapa [Obel.sup.X] FU3-PL-18-TiD1 Fatu Kapa [Aster.sup.X] FU3-PL-17-TiD2 Fatu Kapa Fati Ufu FU3-PL-17-TiG2 Fatu Kapa Fati Ufu FU3-PL-21-TiD1 Fatu Kapa Fati Ufu FU3-PL-21-TiG1 Fatu Kapa Fati Ufu FU3-PL-21-TiD2 Fatu Kapa Fati Ufu FU3-PL-21-TiG2 Fatu Kapa Fati Ufu FU3-PL-20-TiD1 Fatu Kapa Tutafi FU3-PL-20-TiG1 Fatu Kapa Tutafi FU3-PL-21-TiD3 Fatu Kapa Tutafi FU3-PL-21-TiG3 Fatu Kapa Tutafi Tmax (sample) Sample name Description Depth [degrees]C IAPSO Standard, water -- -- FU-PL-05-TiG2 Reference water 1150 -- FU-PL-05-TiG1 Diffuse fluid above worms 1414 32.8 FU-PL-06-TiG4 Beehive type black smoker 1475 134.1 FU-PL-06-TiD4 Beehive type black smoker 1475 136 FU-PL-06-TiG3 Translucent smoker 1475 342.3 FU-PL-06-TiD3 Translucent smoker 1475 337.7 FU-PL-06-TiD1 Black smoker 1475 343.2 FU-PL-06-TiG1 Black smoker 1475 343.2 FU3-PL-03-TiD3 Reference water 1488 -- FU3-PL-14-TiG2 Reference water 1572 2 FU3-PL-04-TiD3 Translucent smoker 1554 213 FU3-PL-04-TiG3 Translucent smoker 1554 213 FU3-PL-08-TiD1 Translucent smoker 1555 289 FU3-PL-08-TiG1 Translucent smoker 1555 289 FU3-PL-08-TiD2 Translucent smoker 1555 291 FU3-PL-09-TiD2 Beehive type black 1650 197 smoker + bacterial mat FU3-PL-09-TiG2 Beehive type black 1559 197 smoker + bacterial mat FU3-PL-06-TiD1 Translucent smoker 1663 278 FU3-PL-06-TiG1 Translucent smoker 1663 278 FU3-PL-08-TiD3 Translucent smoker 1664 281 FU3-PL-08-TiG3 Translucent smoker 1664 281 FU3-PL-11-TiD3 Translucent smoker 1573 259 FU3-PL-11-TiG3 Translucent smoker 1573 259 FU3-PL-14-TiD1 Translucent smoker 1572 271 FU3-PL-14-TiG1 Translucent smoker 1572 271 FU3-PL-14-TiD2 Translucent smoker 1669 272 FU3-PL-14-TiD3 Translucent smoker 1636 287 FU3-PL-14-TiG3 Translucent smoker 1636 287 FU3-PL-18-TiD1 Translucent smoker 1540 265 FU3-PL-17-TiD2 Grey smoker 1522 299 FU3-PL-17-TiG2 Grey smoker 1522 299 FU3-PL-21-TiD1 Grey smoker 1523 302 FU3-PL-21-TiG1 Grey smoker 1523 302 FU3-PL-21-TiD2 White smoker 1503 -- FU3-PL-21-TiG2 White smoker 1503 -- FU3-PL-20-TiD1 Grey smoker 1580 316 FU3-PL-20-TiG1 Grey smoker 1580 316 FU3-PL-21-TiD3 White smoker 1626 293 FU3-PL-21-TiG3 White smoker 1626 293 Tmax [d.sup.20] (chimney) Kg Sample name [degrees]C pH [m.sup.-3] IAPSO -- -- FU-PL-05-TiG2 -- -- 1.023 FU-PL-05-TiG1 -- 5.96 1.023 FU-PL-06-TiG4 332 6.07 1.022 FU-PL-06-TiD4 332 5.58 1.021 FU-PL-06-TiG3 330.7 2.24 1.017 FU-PL-06-TiD3 330.7 2.37 1.018 FU-PL-06-TiD1 345.1 2.36 1.02 FU-PL-06-TiG1 345.1 3.32 1.028 FU3-PL-03-TiD3 -- -- -- FU3-PL-14-TiG2 -- -- -- FU3-PL-04-TiD3 279 4.65 1.03 FU3-PL-04-TiG3 279 4.64 1.03 FU3-PL-08-TiD1 280 4 1.031 FU3-PL-08-TiG1 280 3.41 1.031 FU3-PL-08-TiD2 280 3.83 1.031 FU3-PL-09-TiD2 236 5.19 1.026 FU3-PL-09-TiG2 236 5.42 1.025 FU3-PL-06-TiD1 270 5.03 1.024 FU3-PL-06-TiG1 270 4.91 1.024 FU3-PL-08-TiD3 281 2.78 1.024 FU3-PL-08-TiG3 281 4.17 1.024 FU3-PL-11-TiD3 258 4.9 1.025 FU3-PL-11-TiG3 258 4.43 1.025 FU3-PL-14-TiD1 271 3.73 1.025 FU3-PL-14-TiG1 271 3.97 1.025 FU3-PL-14-TiD2 -- 4.59 1.03 FU3-PL-14-TiD3 -- 4.28 1.03 FU3-PL-14-TiG3 -- 5.37 1.028 FU3-PL-18-TiD1 260 4.35 1.027 FU3-PL-17-TiD2 303 4.26 1.031 FU3-PL-17-TiG2 303 4.22 1.031 FU3-PL-21-TiD1 301 3.81 1.032 FU3-PL-21-TiG1 301 4.69 1.03 FU3-PL-21-TiD2 284 3.27 1.028 FU3-PL-21-TiG2 284 4.22 1.026 FU3-PL-20-TiD1 317 4.1 1.029 FU3-PL-20-TiG1 317 4.14 1.029 FU3-PL-21-TiD3 294 2.92 1.028 FU3-PL-21-TiG3 294 3.65 1.027 S NaCl Cl Si Sample name [per thousand] (wt%) mM mM IAPSO 35 3.2 546 0.0 FU-PL-05-TiG2 35 3.2 551 0.1 FU-PL-05-TiG1 35 3.2 549 0.2 FU-PL-06-TiG4 33 3.0 516 1.0 FU-PL-06-TiD4 31 2.8 485 2.1 FU-PL-06-TiG3 32 2.9 497 8.2 FU-PL-06-TiD3 33 3.0 517 8.4 FU-PL-06-TiD1 47 4.3 735 14.6 FU-PL-06-TiG1 44 4.0 689 10.8 FU3-PL-03-TiD3 -- 3.3 565 0.0 FU3-PL-14-TiG2 36 3.3 557 0.0 FU3-PL-04-TiD3 45 4.1 704 0.7 FU3-PL-04-TiG3 44 4.0 686 1.0 FU3-PL-08-TiD1 49 4.5 770 3.8 FU3-PL-08-TiG1 49 4.5 772 4.7 FU3-PL-08-TiD2 48 4.4 748 4.3 FU3-PL-09-TiD2 40 3.7 629 1.7 FU3-PL-09-TiG2 38 3.5 600 1.0 FU3-PL-06-TiD1 37 3.4 576 1.7 FU3-PL-06-TiG1 37 3.4 579 0.7 FU3-PL-08-TiD3 38 3.5 594 4.5 FU3-PL-08-TiG3 38 3.5 592 4.0 FU3-PL-11-TiD3 41 3.7 637 1.4 FU3-PL-11-TiG3 43 3.9 664 4.1 FU3-PL-14-TiD1 43 3.9 665 4.2 FU3-PL-14-TiG1 42 3.9 661 4.1 FU3-PL-14-TiD2 49 4.5 769 4.5 FU3-PL-14-TiD3 47 4.3 729 3.7 FU3-PL-14-TiG3 43 3.9 672 2.5 FU3-PL-18-TiD1 44 4.1 693 3.7 FU3-PL-17-TiD2 47 4.3 739 3.3 FU3-PL-17-TiG2 48 4.4 748 3.5 FU3-PL-21-TiD1 50 4.6 784 4.7 FU3-PL-21-TiG1 45 4.1 708 2.7 FU3-PL-21-TiD2 44 4.1 694 4.9 FU3-PL-21-TiG2 42 3.9 661 3.9 FU3-PL-20-TiD1 46 4.2 720 2.6 FU3-PL-20-TiG1 46 4.2 723 2.3 FU3-PL-21-TiD3 45 4.1 701 5.1 FU3-PL-21-TiG3 45 4.1 700 5.0 S[O.sub.4] Br Na K Sample name mM [micro]M mM mM IAPSO 28.2 839 468 10.2 FU-PL-05-TiG2 29.0 833 457 9.8 FU-PL-05-TiG1 29.3 833 457 9.9 FU-PL-06-TiG4 27.0 822 448 10.6 FU-PL-06-TiD4 23.9 994 406 9.5 FU-PL-06-TiG3 8.8 738 388 18.5 FU-PL-06-TiD3 10.7 770 405 16.6 FU-PL-06-TiD1 6.2 1135 612 29.5 FU-PL-06-TiG1 12.0 1051 565 23.7 FU3-PL-03-TiD3 28.8 841 483 10.4 FU3-PL-14-TiG2 28.7 841 477 10.4 FU3-PL-04-TiD3 10.9 1300 519 39.8 FU3-PL-04-TiG3 12.9 1240 513 36.5 FU3-PL-08-TiD1 1.3 1574 535 54.2 FU3-PL-08-TiG1 0.7 1592 537 54.7 FU3-PL-08-TiD2 0.5 1537 520 52.9 FU3-PL-09-TiD2 19.8 1052 500 24.4 FU3-PL-09-TiG2 23.8 959 489 18.5 FU3-PL-06-TiD1 18.5 927 482 28.5 FU3-PL-06-TiG1 12.7 984 476 37.8 FU3-PL-08-TiD3 1.1 1139 479 59.6 FU3-PL-08-TiG3 1.9 1120 477 57.7 FU3-PL-11-TiD3 8.3 1142 509 49.8 FU3-PL-11-TiG3 1.9 1268 518 63.5 FU3-PL-14-TiD1 1.1 1282 519 66.2 FU3-PL-14-TiG1 0.8 1279 515 65.7 FU3-PL-14-TiD2 0.7 1506 577 69.4 FU3-PL-14-TiD3 15.0 1283 557 58.8 FU3-PL-14-TiG3 27.0 1103 528 42.5 FU3-PL-18-TiD1 1.0 1344 533 64.9 FU3-PL-17-TiD2 9.3 1378 555 38.4 FU3-PL-17-TiG2 8.7 1402 562 39.8 FU3-PL-21-TiD1 1.4 1554 577 47.3 FU3-PL-21-TiG1 10.5 1292 544 34.7 FU3-PL-21-TiD2 0.4 1359 534 39.3 FU3-PL-21-TiG2 7.0 1217 520 32.0 FU3-PL-20-TiD1 0.6 1409 543 54.6 FU3-PL-20-TiG1 1.0 1409 543 54.7 FU3-PL-21-TiD3 0.9 1367 528 51.3 FU3-PL-21-TiG3 0.8 1371 528 51.0 Mg Ca Li Li Sample name mM mM [micro]M [micro]M IAPSO 53.2 10.3 27 27 FU-PL-05-TiG2 53.2 10.6 25 28 FU-PL-05-TiG1 53.2 10.6 28 52 FU-PL-06-TiG4 49.8 10.5 33 54 FU-PL-06-TiD4 45.7 10.2 32 55 FU-PL-06-TiG3 24.6 11.6 149 156 FU-PL-06-TiD3 28.6 10.8 115 149 FU-PL-06-TiD1 26.5 10.9 238 249 FU-PL-06-TiG1 34.9 10.8 176 197 FU3-PL-03-TiD3 54.5 10.7 22 51 FU3-PL-14-TiG2 54.2 10.8 23 nm FU3-PL-04-TiD3 18.7 69.6 472 568 FU3-PL-04-TiG3 22.5 62.8 420 504 FU3-PL-08-TiD1 0.8 98.9 705 804 FU3-PL-08-TiG1 0.5 98.7 708 807 FU3-PL-08-TiD2 0.6 95.3 684 806 FU3-PL-09-TiD2 37.4 37.8 230 293 FU3-PL-09-TiG2 44.3 26.4 143 193 FU3-PL-06-TiD1 35.2 17.9 260 310 FU3-PL-06-TiG1 23.6 22.2 391 455 FU3-PL-08-TiD3 0.4 31.5 690 746 FU3-PL-08-TiG3 2.7 30.3 655 720 FU3-PL-11-TiD3 15.5 35.0 541 612 FU3-PL-11-TiG3 2.0 44.7 733 802 FU3-PL-14-TiD1 0.8 43.4 764 823 FU3-PL-14-TiG1 0.8 42.9 757 825 FU3-PL-14-TiD2 1.3 65.5 757 nm FU3-PL-14-TiD3 11.1 65.0 621 nm FU3-PL-14-TiG3 25.3 54.6 415 nm FU3-PL-18-TiD1 1.2 51.1 755 nm FU3-PL-17-TiD2 17.6 66.6 543 nm FU3-PL-17-TiG2 15.9 69.7 569 nm FU3-PL-21-TiD1 1.4 86.2 717 nm FU3-PL-21-TiG1 19.3 60.3 474 nm FU3-PL-21-TiD2 1.0 63.3 573 nm FU3-PL-21-TiG2 13.3 50.6 435 nm FU3-PL-20-TiD1 0.9 65.4 628 nm FU3-PL-20-TiG1 0.7 66.4 630 nm FU3-PL-21-TiD3 0.3 63.9 640 nm FU3-PL-21-TiG3 0.8 63.3 633 nm Rb Sr Fe Mn Sample name [micro]M [micro]M [micro]M [micro]M IAPSO 1.3 90 <LOD <LOD FU-PL-05-TiG2 4.4 93 <LOD <LOD FU-PL-05-TiG1 4.6 92 <LOD <LOD FU-PL-06-TiG4 5.3 84 123 32 FU-PL-06-TiD4 6.1 74 78 76 FU-PL-06-TiG3 26 7.3 4796 862 FU-PL-06-TiD3 24 9.4 4283 788 FU-PL-06-TiD1 46 3.4 9884 1416 FU-PL-06-TiG1 36 9.1 6845 1064 FU3-PL-03-TiD3 6 <LOD <LOD <LOD FU3-PL-14-TiG2 nm nm nm nm FU3-PL-04-TiD3 80 <LOD 169 166 FU3-PL-04-TiG3 71 169 nm 141 FU3-PL-08-TiD1 121 268 655 265 FU3-PL-08-TiG1 122 283 167 269 FU3-PL-08-TiD2 116 <LOD 148 259 FU3-PL-09-TiD2 36 149 nm 65 FU3-PL-09-TiG2 23 <LOD nm 23 FU3-PL-06-TiD1 42 101 nm nm FU3-PL-06-TiG1 63 <LOD 18 32 FU3-PL-08-TiD3 104 115 nm 48 FU3-PL-08-TiG3 96 <LOD 288 39 FU3-PL-11-TiD3 78 <LOD 38 26 FU3-PL-11-TiG3 110 160 nm 46 FU3-PL-14-TiD1 120 144 28 64 FU3-PL-14-TiG1 119 <LOD nm 62 FU3-PL-14-TiD2 nm nm nm nm FU3-PL-14-TiD3 nm nm nm nm FU3-PL-14-TiG3 nm nm nm nm FU3-PL-18-TiD1 nm nm nm nm FU3-PL-17-TiD2 nm nm nm nm FU3-PL-17-TiG2 nm nm nm nm FU3-PL-21-TiD1 nm nm nm nm FU3-PL-21-TiG1 nm nm nm nm FU3-PL-21-TiD2 nm nm nm nm FU3-PL-21-TiG2 nm nm nm nm FU3-PL-20-TiD1 nm nm nm nm FU3-PL-20-TiG1 nm nm nm nm FU3-PL-21-TiD3 nm nm nm nm FU3-PL-21-TiG3 nm nm nm nm Cu Zn Br/Cl Sample name [micro]M [micro]M Na/Cl x [10.sup.3] IAPSO <LOD <LOD 0.9 1.5 FU-PL-05-TiG2 <LOD <LOD 0.83 1.5 FU-PL-05-TiG1 1.4 1.5 0.83 1.5 FU-PL-06-TiG4 1.7 3.1 0.87 1.6 FU-PL-06-TiD4 1.3 1.5 0.84 2.0 FU-PL-06-TiG3 14 45 0.78 1.5 FU-PL-06-TiD3 4.2 41 0.78 1.5 FU-PL-06-TiD1 2.5 175 0.83 1.5 FU-PL-06-TiG1 20 77 0.82 1.5 FU3-PL-03-TiD3 <LOD <LOD 0.85 1.5 FU3-PL-14-TiG2 nm nm 0.86 1.5 FU3-PL-04-TiD3 nm <LOD 0.74 1.8 FU3-PL-04-TiG3 8.2 <LOD 0.75 1.8 FU3-PL-08-TiD1 6.6 <LOD 0.69 2.0 FU3-PL-08-TiG1 nm <LOD 0.70 2.1 FU3-PL-08-TiD2 nm <LOD 0.70 2.1 FU3-PL-09-TiD2 nm 1.0 0.79 1.7 FU3-PL-09-TiG2 nm <LOD 0.81 1.6 FU3-PL-06-TiD1 nm <LOD 0.84 1.6 FU3-PL-06-TiG1 nm <LOD 0.82 1.7 FU3-PL-08-TiD3 nm 4.4 0.80 1.9 FU3-PL-08-TiG3 nm <LOD 0.81 1.9 FU3-PL-11-TiD3 nm <LOD 0.80 1.8 FU3-PL-11-TiG3 nm 2.5 0.78 1.9 FU3-PL-14-TiD1 nm 3.4 0.78 1.9 FU3-PL-14-TiG1 nm <LOD 0.78 1.9 FU3-PL-14-TiD2 nm nm 0.75 2.0 FU3-PL-14-TiD3 nm nm 0.76 1.8 FU3-PL-14-TiG3 nm nm 0.79 1.6 FU3-PL-18-TiD1 nm nm 0.77 1.9 FU3-PL-17-TiD2 nm nm 0.75 1.9 FU3-PL-17-TiG2 nm nm 0.75 1.9 FU3-PL-21-TiD1 nm nm 0.74 2.0 FU3-PL-21-TiG1 nm nm 0.77 1.8 FU3-PL-21-TiD2 nm nm 0.77 2.0 FU3-PL-21-TiG2 nm nm 0.79 1.8 FU3-PL-20-TiD1 nm nm 0.75 2.0 FU3-PL-20-TiG1 nm nm 0.75 1.9 FU3-PL-21-TiD3 nm nm 0.75 1.9 FU3-PL-21-TiG3 nm nm 0.75 2.0 C[H.sub.4] Sample name Na/K /Mn IAPSO 46 -- FU-PL-05-TiG2 47 -- FU-PL-05-TiG1 46 -- FU-PL-06-TiG4 42 -- FU-PL-06-TiD4 43 0.010 FU-PL-06-TiG3 21 0.007 FU-PL-06-TiD3 24 -- FU-PL-06-TiD1 21 -- FU-PL-06-TiG1 24 0.001 FU3-PL-03-TiD3 46 -- FU3-PL-14-TiG2 46 -- FU3-PL-04-TiD3 13 -- FU3-PL-04-TiG3 14 0.805 FU3-PL-08-TiD1 10 0.886 FU3-PL-08-TiG1 10 0.762 FU3-PL-08-TiD2 10 -- FU3-PL-09-TiD2 21 0.902 FU3-PL-09-TiG2 26 -- FU3-PL-06-TiD1 17 -- FU3-PL-06-TiG1 13 -- FU3-PL-08-TiD3 8 1.365 FU3-PL-08-TiG3 8 -- FU3-PL-11-TiD3 10 -- FU3-PL-11-TiG3 8 1.848 FU3-PL-14-TiD1 8 1.078 FU3-PL-14-TiG1 8 -- FU3-PL-14-TiD2 8 -- FU3-PL-14-TiD3 9 -- FU3-PL-14-TiG3 12 -- FU3-PL-18-TiD1 8 -- FU3-PL-17-TiD2 14 -- FU3-PL-17-TiG2 14 -- FU3-PL-21-TiD1 12 -- FU3-PL-21-TiG1 16 -- FU3-PL-21-TiD2 14 -- FU3-PL-21-TiG2 16 -- FU3-PL-20-TiD1 10 -- FU3-PL-20-TiG1 10 -- FU3-PL-21-TiD3 10 -- FU3-PL-21-TiG3 10 -- Table 4: Measured gas concentration and associated stable isotopic ratios hydrothermal fluids from the Kulo Lasi and Fatu Kapa vent fields. Values of log f[H.sub.2] were calculated using SUPCRT92 with the slop98 data base. [H.sub.2]S [N.sub.2] Sample name Site mM mM Seawater 0.59 FU-PL-05-TiG1 Kulo Lasi 0.12 FU-PL-06-TiD4 Kulo Lasi 1.66 0.10 FU-PL-06-TiG3 Kulo Lasi 5.05 1.43 FU-PL-06-TiD1 Kulo Lasi 0.39 2.48 FU-PL-06-TiG1 Kulo Lasi 0.79 FU3-PL-04-TiG3 Stephanie 0.91 0.93 FU3-PL-08-TiD1 Stephanie 1.23 1.98 FU3-PL-08-TiG1 Stephanie 0.98 2.47 FU3-PL-09-TiD2 Stephanie 0.23 0.48 FU3-PL-06-TiD1 Carla 1.34 0.50 FU3-PL-08-TiD3 Carla 0.19 3.33 FU3-PL-11-TiG3 Idefx 1.13 0.78 FU3-PL-14-TiD1 Idefx 1.00 1.20 FU3-PL-14-TiD2 Obelx 0.85 1.05 FU3-PL-14-TiD3 Obelx 0.54 0.93 FU3-PL-18-TiD1 Asterx 0.98 0.89 FU3-PL-17-TiG2 Fati Ufu 1.76 0.84 FU3-PL-21-TiD2 Fati Ufu 0.71 2.07 FU3-PL-20-TiD1 Tutafi 2.36 1.18 FU3-PL-21-TiD3 Tutafi 0.84 1.67 [sup.3]He [H.sub.2] Sample name mM R/Ra mM Seawater nm nm <LOD FU-PL-05-TiG1 nm nm <LOQ FU-PL-06-TiD4 nm nm 1.14 FU-PL-06-TiG3 nm nm 19.8 FU-PL-06-TiD1 nm nm 6.18 FU-PL-06-TiG1 nm nm 1.04 FU3-PL-04-TiG3 1.1E - 08 8.6 0.03 FU3-PL-08-TiD1 nm 0.06 FU3-PL-08-TiG1 4.4E - 09 7.6 0.05 FU3-PL-09-TiD2 1.9E-09 7.0 0.04 FU3-PL-06-TiD1 7.IE - 09 9.6 0.01 FU3-PL-08-TiD3 1.7E-08 9.8 0.05 FU3-PL-11-TiG3 1.8E-08 9.8 0.03 FU3-PL-14-TiD1 5.5E - 09 8.7 0.02 FU3-PL-14-TiD2 3.8E-08 9.8 0.03 FU3-PL-14-TiD3 5.2E-09 8.4 0.02 FU3-PL-18-TiD1 nm nm 0.01 FU3-PL-17-TiG2 2.7E - 08 9.9 0.01 FU3-PL-21-TiD2 3.IE - 09 9.9 0.03 FU3-PL-20-TiD1 1.4E-08 9.2 0.05 FU3-PL-21-TiD3 nm nm 0.03 log C[H.sub.4] C[O.sub.2] Sample name f[H.sub.2] mM mM Seawater -- <LOD 2.3 FU-PL-05-TiG1 -- 0.001 2.6 FU-PL-06-TiD4 -- 0.001 1.3 FU-PL-06-TiG3 -3.11 0.006 5.1 FU-PL-06-TiD1 -3.62 0.004 3.0 FU-PL-06-TiG1 -4.40 0.001 1.0 FU3-PL-04-TiG3 -1.87 0.114 15.5 FU3-PL-08-TiD1 -1.57 0.235 29.0 FU3-PL-08-TiG1 -1.65 0.205 25.7 FU3-PL-09-TiD2 -1.75 0.059 6.0 FU3-PL-06-TiD1 -2.35 0.021 4.5 FU3-PL-08-TiD3 -1.65 0.066 11.9 FU3-PL-11-TiG3 -1.87 0.085 10.0 FU3-PL-14-TiD1 -2.05 0.069 10.1 FU3-PL-14-TiD2 -1.87 0.110 8.7 FU3-PL-14-TiD3 -2.05 0.165 9.2 FU3-PL-18-TiD1 -2.35 0.067 9.2 FU3-PL-17-TiG2 -2.59 0.070 21.5 FU3-PL-21-TiD2 -2.11 0.111 12.6 FU3-PL-20-TiDl -1.89 0.156 22.2 FU3-PL-21-TiD3 -2.11 0.053 11.7 [C.sub.2] [C.sub.2] [C.sub.3] [C.sub.3] [H.sub.6] [H.sub.4] [H.sub.8] [H.sub.6] Sample name [micro]M [micro]M [micro]M [micro]M Seawater nm nm nm nm FU-PL-05-TiG1 <LOD nm <LOD nm FU-PL-06-TiD4 0.02 0.005 0.006 0.004 FU-PL-06-TiG3 0.11 0.042 0.028 0.030 FU-PL-06-TiD1 0.1 0.017 0.017 0.020 FU-PL-06-TiGl 0.02 0.009 0.005 0.007 FU3-PL-04-TiG3 <LOD <LOD <LOD <LOD FU3-PL-08-TiD1 <LOD <LOD <LOD <LOD FU3-PL-08-TiG1 <LOD <LOD <LOD <LOD FU3-PL-09-TiD2 <LOD <LOD <LOD <LOD FU3-PL-06-TiD1 <LOD <LOD <LOD <LOD FU3-PL-08-TiD3 <LOD <LOD <LOD <LOD FU3-PL-11-TiG3 <LOD <LOD <LOD <LOD FU3-PL-14-TiD1 <LOD <LOD <LOD <LOD FU3-PL-14-TiD2 <LOD <LOD <LOD <LOD FU3-PL-14-TiD3 <LOD <LOD <LOD <LOD FU3-PL-18-TiD1 <LOD <LOD <LOD <LOD FU3-PL-17-TiG2 <LOD <LOD <LOD <LOD FU3-PL-21-TiD2 <LOD <LOD <LOD <LOD FU3-PL-20-TiD1 <LOD <LOD <LOD <LOD FU3-PL-21-TiD3 <LOD <LOD <LOD <LOD n-[C.sub.4] n-[C.sub.5] [delta]D [H.sub.10] [H.sub.12] ([H.sub.2]) Sample name [micro]M [micro]M [per thousand] Seawater nm nm nm FU-PL-05-TiG1 <LOD <LOD nm FU-PL-06-TiD4 0.005 0.005 -323 FU-PL-06-TiG3 0.024 0.006 -306 FU-PL-06-TiD1 0.012 0.004 -300 FU-PL-06-TiG1 0.005 0.001 -316 FU3-PL-04-TiG3 <LOD 1.7 nm FU3-PL-08-TiD1 <LOD 3.2 -676 FU3-PL-08-TiG1 <LOD 2.9 nm FU3-PL-09-TiD2 <LOD 0.7 -436 FU3-PL-06-TiD1 <LOD 0.5 nm FU3-PL-08-TiD3 <LOD 1.5 -410 FU3-PL-11-TiG3 <LOD 1.1 nm FU3-PL-14-TiD1 <LOD 1.1 -417 FU3-PL-14-TiD2 <LOD 1.0 -407 FU3-PL-14-TiD3 <LOD 1.0 nm FU3-PL-18-TiD1 <LOD 1.0 -412 FU3-PL-17-TiG2 <LOD 2.3 - FU3-PL-21-TiD2 <LOD 1.5 -410 FU3-PL-20-TiD1 <LOD 2.4 -396 FU3-PL-21-TiD3 <LOD 1.4 -415 [delta]D [delta][sup.13]C (C[H.sub.4]) (C[O.sub.2]) Sample name [per thousand] [per thousand] Seawater nm nm FU-PL-05-TiG1 nm nm FU-PL-06-TiD4 n.m. -3.2 FU-PL-06-TiG3 n.m. -4.1 FU-PL-06-TiD1 n.m. -1.9 FU-PL-06-TiG1 n.m. -0.2 FU3-PL-04-TiG3 nm nm FU3-PL-08-TiD1 -108 -5 FU3-PL-08-TiG1 nm nm FU3-PL-09-TiD2 -111 -5.3 FU3-PL-06-TiD1 nm nm FU3-PL-08-TiD3 -109 -4.7 FU3-PL-11-TiG3 nm nm FU3-PL-14-TiD1 -110 -4.9 FU3-PL-14-TiD2 -113 -5 FU3-PL-14-TiD3 nm nm FU3-PL-18-TiD1 -111 -4.9 FU3-PL-17-TiG2 -93 -2.3 FU3-PL-21-TiD2 -109 -4.4 FU3-PL-20-TiD1 -111 -4.5 FU3-PL-21-TiD3 -109 -4.7 [delta][sup.13]C ([C.sub.2] (C[H.sub.4]) [H.sub.6]) Sample name [per thousand] [per thousand] Seawater nm nm FU-PL-05-TiG1 nm nm FU-PL-06-TiD4 -29 -27 FU-PL-06-TiG3 -23 -26 FU-PL-06-TiD1 -28 -24 FU-PL-06-TiG1 -27.2 -22 FU3-PL-04-TiG3 nm nm FU3-PL-08-TiD1 -21.7 nm FU3-PL-08-TiG1 nm nm FU3-PL-09-TiD2 -22.2 nm FU3-PL-06-TiD1 nm nm FU3-PL-08-TiD3 -21.5 nm FU3-PL-11-TiG3 nm nm FU3-PL-14-TiD1 -23.8 nm FU3-PL-14-TiD2 -24 nm FU3-PL-14-TiD3 nm nm FU3-PL-18-TiD1 -23.6 nm FU3-PL-17-TiG2 -6.1 nm FU3-PL-21-TiD2 -23.3 nm FU3-PL-20-TiD1 -23.6 nm FU3-PL-21-TiD3 -24.2 nm ([C.sub.3] ([C.sub.4] [H.sub.8]) [H.sub.10]) Sample name [per thousand] [per thousand] Seawater nm nm FU-PL-05-TiG1 nm nm FU-PL-06-TiD4 -26 nm FU-PL-06-TiG3 -26 -24 FU-PL-06-TiD1 -26 -24 FU-PL-06-TiG1 -26 -24 FU3-PL-04-TiG3 nm nm FU3-PL-08-TiD1 nm nm FU3-PL-08-TiG1 nm nm FU3-PL-09-TiD2 nm nm FU3-PL-06-TiD1 nm nm FU3-PL-08-TiD3 nm nm FU3-PL-11-TiG3 nm nm FU3-PL-14-TiD1 nm nm FU3-PL-14-TiD2 nm nm FU3-PL-14-TiD3 nm nm FU3-PL-18-TiD1 nm nm FU3-PL-17-TiG2 nm nm FU3-PL-21-TiD2 nm nm FU3-PL-20-TiD1 nm nm FU3-PL-21-TiD3 nm nm Table 5: Endmember compositions in fluids from the Kulo Lasi and Fatu Kapa vent fields. Kulo Lasi endmembers cannot be extrapolated at Mg = 0. Values presented here for both brine and condensed vapour phases correspond to concentrations in the fluid with the lowest Mg. Elemental compositions in endmember fluids from the various sites of the Fatu Kapa vent field were calculated using the mixing lines (Figure SI) and assuming Mg = 0. Values of the purest fluid were used when linear regression was not possible (*). Note that only one sample was available for the [Aster.sup.X] site (1). T Zone Site Depth [degrees]C pH Kulo Fasi NaCl poor 1475 345 2.24 Kulo Fasi NaCl rich 1475 345 2.36 Fatu Kapa Stephanie 1555 280 3.4 Fatu Kapa Carla 1664 280 2.8 Fatu Kapa [Idef.sup.X] 1572 270 3.7 Fatu Kapa [Obel.sup.X] 1669 270 4.6 Fatu Kapa [Aster.sup.X](1) 1540 265 4.4 Fatu Kapa Fati Ufu 1523 300 3.8 Fatu Kapa Fati Ufu 1503 280 3.3 Fatu Kapa Tutafi 1580 315 4.1 IAPSO Standard sw -- -- -- Kulo Fasi Reference sw 1150 -- -- Fatu Kapa Reference sw 1488 -- -- Fatu Kapa Reference sw 1572 2 -- Br Zone NaCl (wt%) Cl mM Si mM SO4 mM [micro]M Kulo Fasi 2.9 497 8.2 8.8 738 Kulo Fasi 4.3 735 14.6 6.2 1135 Fatu Kapa 4.5 767 4.7 * 0.0 1569 Fatu Kapa 3.5 594 4.3 0.0 1132 Fatu Kapa 3.9 665 4.2 * 0.0 1282 Fatu Kapa 4.5 771 4.6 0.0 1458 Fatu Kapa 4.1 693 3.7 1.0 1344 Fatu Kapa 4.6 790 4.9 0.0 1589 Fatu Kapa 4.1 700 4.9 0.0 1380 Fatu Kapa 4.2 713 5.1 0.0 1405 IAPSO 3.2 546 0.0 28.2 839 Kulo Fasi 3.2 551 0.1 29.0 833 Fatu Kapa 3.3 565 0.0 28.8 841 Fatu Kapa 3.3 557 0.0 28.7 841 Li Zone Na mM K mM Mg mM Ca mM [micro]M Kulo Fasi 388 18.5 24.6 11.6 149 Kulo Fasi 612 29.5 26.5 10.9 238 Fatu Kapa 532 54.5 0.0 98.9 708 Fatu Kapa 477 59.9 0.0 31.4 691 Fatu Kapa 518 66.4 0.0 44.3 751 Fatu Kapa 580 71.0 0.0 85.9 777 Fatu Kapa 533 64.9 1.2 51.1 755 Fatu Kapa 580 48.2 0.0 85.4 722 Fatu Kapa 538 40.0 0.0 65.0 583 Fatu Kapa 535 52.9 0.0 65.1 635 IAPSO 468 10.2 53.2 10.3 27 Kulo Fasi 457 9.8 53.2 10.6 25 Fatu Kapa 483 10.4 54.5 10.7 22 Fatu Kapa 477 10.4 54.2 10.8 23 Rb Sr Fe Mn Zone [micro]M [micro]M [micro]M [micro]M Kulo Fasi 26 7.3 4796 862 Kulo Fasi 46 3.4 9884 1416 Fatu Kapa 114 282 * 655 * 268 Fatu Kapa 105 114 * 287 * 53 Fatu Kapa 113 160 * 28 * 60 Fatu Kapa nm nm nm nm Fatu Kapa nm nm nm nm Fatu Kapa nm nm nm nm Fatu Kapa nm nm nm nm Fatu Kapa nm nm nm nm IAPSO 1.3 90 <LOD <LOD Kulo Fasi 4.4 93 <LOD <LOD Fatu Kapa 5.8 <LOD <LOD <LOD Fatu Kapa nm nm nm nm Cu Zn Br/Cl Zone [micro]M [micro]M Na/Cl x [10.sup.3] Kulo Fasi 14 45 0.78 1.48 Kulo Fasi 2.5 175 0.83 1.54 Fatu Kapa 6.6 * <LOD 0.69 2.05 Fatu Kapa nm 4.4 * 0.80 1.90 Fatu Kapa nm 3.4 * 0.78 1.93 Fatu Kapa nm nm 0.75 1.89 Fatu Kapa nm nm 0.77 1.94 Fatu Kapa nm nm 0.73 2.01 Fatu Kapa nm nm 0.77 1.97 Fatu Kapa nm nm 0.75 1.97 IAPSO <LOD <LOD 0.9 1.5 Kulo Fasi <LOD <LOD 0.83 1.5 Fatu Kapa <LOD <LOD 0.85 1.5 Fatu Kapa nm nm 0.86 1.5 Zone Na/K CH4/Mn Kulo Fasi 21 0.007 * Kulo Fasi 21 0.001 * Fatu Kapa 10 0.76 * Fatu Kapa 8 1.37 * Fatu Kapa 8 1.08 * Fatu Kapa 8 -- Fatu Kapa 8 -- Fatu Kapa 12 -- Fatu Kapa 13 -- Fatu Kapa 10 -- IAPSO 46 -- Kulo Fasi 47 -- Fatu Kapa 46 -- Fatu Kapa 46 -- * Maximum value when linear regression was not possible; (1) only one sample. Table 6: Measured concentration of Total Organic Carbon (TOC), formate, acetate, and a selection of individual semi-volatile organic compounds extracted from hydrothermal fluids of the Kulo Lasi and Fatu Kapa vent fields. Compound Rt min Units Blank Dry Blank MQ pH -- -- -- Mg -- mM -- -- TOC -- ppm na <0.005 Formate -- Ppb na nd Acetate -- Ppb na nd Nonane 4.68 Ppb nd nd Decane 5.911 Ppb nd <0.03 Undecane 7.183 Ppb nd <0.2 Do decane 8.394 Ppb nd nd Tridecane 9.549 Ppb nd nd Tetradecane 10.641 Ppb nd nd Pentadecane 11.675 Ppb nd nd Hexadecane 12.65 Ppb nd nd Heptadecane 13.576 Ppb nd nd Octadecane 14.452 Ppb nd nd Nonadecane 15.295 Ppb nd nd Eicosane 16.104 Ppb nd nd Nonanoic acid 6.914 Ppb nd nd Decanoic acid 7.542 Ppb nd nd Undecanoic acid 8.178 Ppb nd nd Dodecanoic acid 8.773 Ppb nd nd Tridecanoic acid 9.31 Ppb nd nd Tetradecanoic acid 9.859 Ppb nd <0.06 Pentadecanoic acid 10.355 Ppb nd nd Hexadecanoic acid 10.902 Ppb nd nd Hept a decanoic acid 11.317 Ppb nd nd Octadecanoic acid 11.78 Ppb nd nd Ethyl, Benzene 4.344 Ppb nd <0.1 p~>m-Xylene 4.443 Ppb nd nd o-Xylene 4.708 Ppb nd <0.02 Styrene 4.831 Ppb nd nd isopropyl, Benzene 5.006 Ppb nd nd n-Propyl, Benzene 5.468 Ppb nd nd 1,2,4-triMethyl- 5.572 Ppb nd nd Benzene 1,3,5- triMethyl-Benzene 5.95 Ppb nd nd sec-Butyl-Benzene 6.106 Ppb nd nd 2,isopropyl, Toluene 6.305 Ppb nd nd n-Butyl, Benzene 6.66 Ppb nd <0.08 Naphthalene 8.351 Ppb nd <0.01 Acenaphthene 11.796 Ppb nd nd Fluorene 12.778 Ppb nd nd Phenanthrene 14.582 Ppb nd nd Anthracene 14.788 Ppb nd nd Fluoranthene 17.117 Ppb nd nd Pyrene 17.52 Ppb nd nd FU3-PL- FU3-PL- 14-TiG2 08-TiD2 Compound deepsea water Stephanie pH -- 3.83 Mg 54.2 0.6 TOC na 0.165 Formate na 65.8 Acetate na 1155.1 Nonane 0.85 [+ or -] 0.51 1.59 [+ or -] 0.52 Decane 2.21 [+ or -] 0.44 2.03 [+ or -] 0.44 Undecane 11.35 [+ or -] 0.97 6.79 [+ or -] 0.76 Do decane 3.36 [+ or -] 0.65 1.33 [+ or -] 0.57 Tridecane 1.39 [+ or -] 0.54 0.35 [+ or -] 0.53 Tetradecane 0.53 [+ or -] 0.47 0.56 [+ or -] 0.47 Pentadecane 0.44 [+ or -] 0.28 0.40 [+ or -] 0.28 Hexadecane 0.25 [+ or -] 0.73 0.40 [+ or -] 0.74 Heptadecane 0.57 [+ or -] 0.32 1.08 [+ or -] 0.32 Octadecane 0.17 [+ or -] 0.17 0.30 [+ or -] 0.18 Nonadecane 1.08 [+ or -] 1.34 1.36 [+ or -] 1.35 Eicosane 1.09 [+ or -] 1.23 1.75 [+ or -] 1.27 Nonanoic acid 3.72 [+ or -] 2.53 8.07 [+ or -] 2.96 Decanoic acid 1.17 [+ or -] 1.65 0.86 [+ or -] 1.59 Undecanoic acid 0.18 [+ or -] 0.19 0.29 [+ or -] 0.20 Dodecanoic acid 0.42 [+ or -] 0.48 2.10 [+ or -] 0.51 Tridecanoic acid 0.28 [+ or -] 0.20 0.35 [+ or -] 0.19 Tetradecanoic acid 0.94 [+ or -] 0.32 1.86 [+ or -] 0.31 Pentadecanoic acid 0.54 [+ or -] 0.30 1.44 [+ or -] 0.30 Hexadecanoic acid 1.46 [+ or -] 1.20 6.66 [+ or -] 1.37 Hept a decanoic acid 0.54 [+ or -] 0.61 3.23 [+ or -] 0.58 Octadecanoic acid 0.94 [+ or -] 2.16 8.70 [+ or -] 2.82 Ethyl, Benzene nd <0.1 p~>m-Xylene 0.03 [+ or -] 0.05 0.10 [+ or -] 0.05 o-Xylene 0.02 [+ or -] 0.05 0.07 [+ or -] 0.06 Styrene 0.59 [+ or -] 0.14 0.22 [+ or -] 0.16 isopropyl, Benzene 0.04 [+ or -] 0.05 0.06 [+ or -] 0.05 n-Propyl, Benzene 0.03 [+ or -] 0.04 0.02 [+ or -] 0.04 1,2,4-triMethyl- 0.03 [+ or -] 0.04 0.05 [+ or -] 0.04 Benzene 1,3,5- triMethyl-Benzene 0.02 [+ or -] 0.06 0.11 [+ or -] 0.07 sec-Butyl-Benzene 0.27 [+ or -] 0.05 0.04 [+ or -] 0.04 2,isopropyl, Toluene 0.07 [+ or -] 0.03 0.03 [+ or -] 0.03 n-Butyl, Benzene 0.06 [+ or -] 0.03 0.01 [+ or -] 0.03 Naphthalene 1.39 [+ or -] 0.07 0.49 [+ or -] 0.05 Acenaphthene <0.009 <0.009 Fluorene nd 0.05 [+ or -] 0.03 Phenanthrene 0.02 [+ or -] 0.04 0.10 [+ or -] 0.04 Anthracene nd nd Fluoranthene <0.04 <0.04 Pyrene <0.03 0.03 [+ or -] 0.11 FU3-PL- FU3-PL- 04-TiD3 09-TiG2 Compound Stephanie Stephanie pH 4.65 5.42 Mg 18.7 44.3 TOC na na Formate <LOQ na Acetate 543.2 na Nonane 1.17 [+ or -] 0.51 1.08 [+ or -] 0.51 Decane 2.02 [+ or -] 0.44 2.10 [+ or -] 0.44 Undecane 9.52 [+ or -] 0.87 11.48 [+ or -] 0.98 Do decane 2.30 [+ or -] 0.60 2.98 [+ or -] 0.63 Tridecane 0.73 [+ or -] 0.53 0.86 [+ or -] 0.53 Tetradecane 0.57 [+ or -] 0.47 0.59 [+ or -] 0.47 Pentadecane 0.48 [+ or -] 0.27 0.44 [+ or -] 0.28 Hexadecane 0.42 [+ or -] 0.73 0.49 [+ or -] 0.73 Heptadecane 0.61 [+ or -] 0.32 0.87 [+ or -] 0.32 Octadecane 0.28 [+ or -] 0.18 0.30 [+ or -] 0.18 Nonadecane 1.24 [+ or -] 1.35 1.38 [+ or -] 1.34 Eicosane 1.05 [+ or -]1.25 0.94 [+ or -] 1.23 Nonanoic acid <0.37 5.71 [+ or -] 2.67 Decanoic acid nd 0.53 [+ or -] 1.60 Undecanoic acid nd 0.23 [+ or -] 0.19 Dodecanoic acid 0.55 [+ or -] 0.48 0.55 [+ or -] 0.48 Tridecanoic acid 0.23 [+ or -] 0.21 0.24 [+ or -] 0.21 Tetradecanoic acid 1.44 [+ or -] 0.31 0.87 [+ or -] 0.33 Pentadecanoic acid 0.82 [+ or -] 0.28 0.46 [+ or -] 0.30 Hexadecanoic acid 4.47 [+ or -] 1.27 1.78 [+ or -] 1.20 Hept a decanoic acid nd 0.89 [+ or -] 0.53 Octadecanoic acid 6.32 [+ or -]2.55 1.67 [+ or -] 2.32 Ethyl, Benzene <0.1 nd p~>m-Xylene 0.11 [+ or -] 0.05 0.08 [+ or -] 0.05 o-Xylene 0.06 [+ or -] 0.05 0.02 [+ or -] 0.06 Styrene nd nd isopropyl, Benzene 0.07 [+ or -] 0.05 0.07 [+ or -] 0.05 n-Propyl, Benzene 0.03 [+ or -] 0.04 0.02 [+ or -] 0.04 1,2,4-triMethyl- 0.06 [+ or -] 0.04 0.04 [+ or -] 0.04 Benzene 1,3,5- triMethyl-Benzene 0.08 [+ or -] 0.07 0.06 [+ or -] 0.06 sec-Butyl-Benzene nd 0.04 [+ or -] 0.05 2,isopropyl, Toluene 0.03 [+ or -] 0.03 0.03 [+ or -] 0.03 n-Butyl, Benzene 0.01 [+ or -] 0.02 0.01 [+ or -] 0.03 Naphthalene 0.32 [+ or -] 0.05 0.13 [+ or -] 0.04 Acenaphthene <0.009 <0.009 Fluorene <0.01 <0.01 Phenanthrene 0.06 [+ or -] 0.04 0.06 [+ or -] 0.04 Anthracene nd nd Fluoranthene <0.04 <0.04 Pyrene 0.03 [+ or -] 0.10 <0.03 FU3-PL- FU3-PL- Compound 08-TiG3 Carla 06-TiGl Carla pH 4.17 4.91 Mg 2.7 23.6 TOC na na Formate na na Acetate na na Nonane 0.72 [+ or -] 0.51 0.58 [+ or -] 0.51 Decane 3.05 [+ or -] 0.45 1.63 [+ or -] 0.44 Undecane 13.81 [+ or -] 1.14 9.61 [+ or -] 0.87 Do decane 3.35 [+ or -] 0.65 2.64 [+ or -] 0.61 Tridecane 1.37 [+ or -]0.54 1.39 [+ or -] 0.54 Tetradecane 0.67 [+ or -] 0.46 0.66 [+ or -] 0.46 Pentadecane 0.52 [+ or -] 0.27 0.59 [+ or -] 0.27 Hexadecane 0.64 [+ or -] 0.73 0.59 [+ or -] 0.74 Heptadecane 1.13 [+ or -] 0.33 0.85 [+ or -] 0.32 Octadecane 0.35 [+ or -] 0.18 0.33 [+ or -] 0.18 Nonadecane 1.64 [+ or -] 1.36 1.40 [+ or -] 1.36 Eicosane 1.13 [+ or -] 1.24 1.69 [+ or -] 1.27 Nonanoic acid 4.49 [+ or -] 2.56 3.49 [+ or -] 2.50 Decanoic acid 0.41 [+ or -] 1.65 nd Undecanoic acid 0.25 [+ or -] 0.20 0.28 [+ or -] 0.19 Dodecanoic acid 0.78 [+ or -] 0.48 0.49 [+ or -] 0.47 Tridecanoic acid 0.24 [+ or -] 0.20 0.33 [+ or -] 0.20 Tetradecanoic acid 0.92 [+ or -] 0.32 4.28 [+ or -] 0.35 Pentadecanoic acid 0.76 [+ or -] 0.29 0.57 [+ or -] 0.29 Hexadecanoic acid 3.90 [+ or -] 1.25 2.91 [+ or -] 1.23 Hept a decanoic acid 2.04 [+ or -] 0.54 1.82 [+ or -] 0.54 Octadecanoic acid 6.36 [+ or -] 2.48 3.49 [+ or -] 2.30 Ethyl, Benzene nd <0.1 p-,m-Xylene 0.10 [+ or -] 0.05 0.11 [+ or -] 0.05 o-Xylene 0.03 [+ or -] 0.08 0.06 [+ or -] 0.05 Styrene 0.46 [+ or -] 0.14 nd isopropyl, Benzene 0.06 [+ or -] 0.05 0.08 [+ or -] 0.05 n-Propyl, Benzene 0.03 [+ or -] 0.04 0.03 [+ or -] 0.04 1,2,4-triMethyl- 0.06 [+ or -] 0.05 0.06 [+ or -] 0.04 Benzene 1,3,5- triMethyl-Benzene 0.09 [+ or -] 0.06 0.09 [+ or -] 0.06 sec-Butyl-Benzene 0.05 [+ or -] 0.06 0.05 [+ or -] 0.05 2,isopropyl, Toluene 0.05 [+ or -] 0.03 0.03 [+ or -] 0.03 n-Butyl, Benzene 0.02 [+ or -] 0.03 0.01 [+ or -] 0.02 Naphthalene 1.24 [+ or -] 0.07 0.69 [+ or -] 0.05 Acenaphthene <0.009 <0.009 Fluorene 0.14 [+ or -] 0.03 0.10 [+ or -] 0.03 Phenanthrene 0.29 [+ or -] 0.05 0.13 [+ or -] 0.04 Anthracene nd nd Fluoranthene 0.06 [+ or -] 0.16 <0.04 Pyrene 0.14 [+ or -] 0.11 0.07 [+ or -] 0.10 FU3-PL- Compound 14-TiGl Idefix pH 3.97 Mg 0.8 TOC 0.498 Formate <LOQ Acetate 1033.6 Nonane 0.84 [+ or -] 0.51 Decane 6.92 [+ or -] 0.51 Undecane 23.13 [+ or -] 1.88 Do decane 5.12 [+ or -] 0.76 Tridecane 1.63 [+ or -] 0.55 Tetradecane 0.59 [+ or -] 0.47 Pentadecane 0.43 [+ or -] 0.28 Hexadecane 0.26 [+ or -] 0.73 Heptadecane 1.20 [+ or -] 0.33 Octadecane 0.39 [+ or -] 0.18 Nonadecane 1.33 [+ or -] 1.35 Eicosane 1.03 [+ or -] 1.24 Nonanoic acid 4.91 [+ or -] 2.60 Decanoic acid 0.61 [+ or -] 1.62 Undecanoic acid 0.22 [+ or -] 0.20 Dodecanoic acid 2.01 [+ or -] 0.51 Tridecanoic acid 0.27 [+ or -] 0.20 Tetradecanoic acid 1.41 [+ or -] 0.31 Pentadecanoic acid 1.06 [+ or -] 0.29 Hexadecanoic acid 7.30 [+ or -] 1.41 Hept a decanoic acid 1.04 [+ or -] 0.62 Octadecanoic acid 11.83 [+ or -] 3.29 Ethyl, Benzene <0.1 p-,m-Xylene 0.18 [+ or -] 0.05 o-Xylene 0.14 [+ or -] 0.06 Styrene 0.29 [+ or -] 0.15 isopropyl, Benzene 0.09 [+ or -] 0.05 n-Propyl, Benzene 0.03 [+ or -] 0.04 1,2,4-triMethyl- 0.04 [+ or -] 0.05 Benzene 1,3,5- triMethyl-Benzene 0.11 [+ or -] 0.06 sec-Butyl-Benzene 0.06 [+ or -] 0.05 2,isopropyl, Toluene 0.04 [+ or -] 0.03 n-Butyl, Benzene 0.02 [+ or -] 0.02 Naphthalene 1.08 [+ or -] 0.06 Acenaphthene <0.009 Fluorene 0.16 [+ or -] 0.03 Phenanthrene 0.20 [+ or -] 0.05 Anthracene nd Fluoranthene <0.04 Pyrene 0.10 [+ or -] 0.11 FU3-PL-11- Compound TiD3 Idefix pH 4.9 Mg 15.5 TOC na Formate <LOQ Acetate 995.1 Nonane 0.52 [+ or -] 0.50 Decane 2.20 [+ or -] 0.44 Undecane 10.89 [+ or -] 0.94 Do decane 3.35 [+ or -] 0.65 Tridecane 2.21 [+ or -] 0.57 Tetradecane 0.72 [+ or -] 0.46 Pentadecane 0.60 [+ or -] 0.27 Hexadecane 0.84 [+ or -] 0.74 Heptadecane 1.48 [+ or -] 0.33 Octadecane 0.42 [+ or -] 0.18 Nonadecane 1.83 [+ or -] 1.38 Eicosane 1.46 [+ or -] 1.26 Nonanoic acid 7.12 [+ or -] 2.87 Decanoic acid nd Undecanoic acid nd Dodecanoic acid 0.69 [+ or -] 0.48 Tridecanoic acid 0.25 [+ or -] 0.21 Tetradecanoic acid 2.74 [+ or -] 0.31 Pentadecanoic acid 0.58 [+ or -] 0.30 Hexadecanoic acid 3.61 [+ or -] 1.24 Hept a decanoic acid 1.62 [+ or -] 0.55 Octadecanoic acid 5.15 [+ or -] 2.35 Ethyl, Benzene na p-,m-Xylene na o-Xylene na Styrene na isopropyl, Benzene na n-Propyl, Benzene na 1,2,4-triMethyl- na Benzene 1,3,5- triMethyl-Benzene na sec-Butyl-Benzene na 2,isopropyl, Toluene na n-Butyl, Benzene na Naphthalene na Acenaphthene na Fluorene na Phenanthrene na Anthracene na Fluoranthene na Pyrene na FU3-PL-21-TiG2 Compound Fati Ufu pH 4.22 Mg 13.3 TOC na Formate 111.7 Acetate 1740.9 Nonane 0.64 [+ or -] 0.50 Decane 6.47 [+ or -] 0.50 Undecane 19.13 [+ or -] 1.55 Do decane 4.76 [+ or -] 0.73 Tridecane 1.75 [+ or -] 0.55 Tetradecane 0.69 [+ or -] 0.46 Pentadecane 0.57 [+ or -] 0.27 Hexadecane 0.53 [+ or -] 0.73 Heptadecane 0.85 [+ or -] 0.32 Octadecane 0.49 [+ or -] 0.19 Nonadecane 1.26 [+ or -] 1.33 Eicosane 1.00 [+ or -] 1.23 Nonanoic acid 8.94 [+ or -] 3.09 Decanoic acid 0.84 [+ or -] 1.67 Undecanoic acid 0.26 [+ or -] 0.19 Dodecanoic acid 1.29 [+ or -] 0.49 Tridecanoic acid 0.26 [+ or -] 0.21 Tetradecanoic acid 0.90 [+ or -] 0.32 Pentadecanoic acid 0.52 [+ or -] 0.30 Hexadecanoic acid 3.24 [+ or -] 1.23 Hept a decanoic acid <0.03 Octadecanoic acid 2.64 [+ or -] 2.09 Ethyl, Benzene 0.10 [+ or -] 0.35 p-,m-Xylene 0.33 [+ or -] 0.05 o-Xylene 0.33 [+ or -] 0.07 Styrene 0.21 [+ or -] 0.15 isopropyl, Benzene 0.09 [+ or -] 0.05 n-Propyl, Benzene 0.04 [+ or -] 0.04 1,2,4-triMethyl- 0.08 [+ or -] 0.04 Benzene 1,3,5- triMethyl-Benzene 0.30 [+ or -] 0.07 sec-Butyl-Benzene nd 2,isopropyl, Toluene 0.04 [+ or -] 0.03 n-Butyl, Benzene 0.02 [+ or -] 0.03 Naphthalene 0.90 [+ or -] 0.06 Acenaphthene <0.009 Fluorene 0.14 [+ or -] 0.03 Phenanthrene 0.16 [+ or -] 0.05 Anthracene nd Fluoranthene 0.04 [+ or -] 0.16 Pyrene 0.06 [+ or -] 0.10 FU3-PL-17-TiD2 Compound Fati Ufu pH 4.26 Mg 17.6 TOC 6.514 Formate 721.6 Acetate 2308.8 Nonane 0.50 [+ or -] 0.51 Decane 5.58 [+ or -] 0.48 Undecane 26.06 [+ or -] 2.14 Do decane 6.52 [+ or -] 0.86 Tridecane 3.89 [+ or -] 0.65 Tetradecane 0.64 [+ or -] 0.46 Pentadecane 0.47 [+ or -] 0.28 Hexadecane 0.39 [+ or -] 0.73 Heptadecane 0.67 [+ or -] 0.32 Octadecane 0.29 [+ or -] 0.18 Nonadecane 0.86 [+ or -] 1.33 Eicosane 0.71 [+ or -] 1.24 Nonanoic acid 9.23 [+ or -] 3.10 Decanoic acid 0.56 [+ or -] 1.68 Undecanoic acid 0.34 [+ or -] 0.19 Dodecanoic acid 1.08 [+ or -] 0.49 Tridecanoic acid 0.32 [+ or -] 0.20 Tetradecanoic acid 1.15 [+ or -] 0.32 Pentadecanoic acid 0.78 [+ or -] 0.29 Hexadecanoic acid 4.92 [+ or -] 1.29 Hept a decanoic acid 2.89 [+ or -] 0.59 Octadecanoic acid 5.26 [+ or -] 2.40 Ethyl, Benzene <0.1 p-,m-Xylene 0.21 [+ or -] 0.05 o-Xylene 0.19 [+ or -] 0.06 Styrene 0.20 [+ or -] 0.15 isopropyl, Benzene 0.04 [+ or -] 0.06 n-Propyl, Benzene 0.03 [+ or -] 0.04 1,2,4-triMethyl- 0.07 [+ or -] 0.05 Benzene 1,3,5- triMethyl-Benzene 0.25 [+ or -] 0.06 sec-Butyl-Benzene 0.05 [+ or -] 0.05 2,isopropyl, Toluene 0.04 [+ or -] 0.03 n-Butyl, Benzene 0.02 [+ or -] 0.02 Naphthalene 0.64 [+ or -] 0.05 Acenaphthene <0.009 Fluorene 0.09 [+ or -] 0.03 Phenanthrene 0.10 [+ or -] 0.04 Anthracene nd Fluoranthene <0.04 Pyrene 0.05 [+ or -] 0.11 FU3-PL-21-TiGl Compound Fati Ufu pH 4.69 Mg 19.3 TOC na Formate na Acetate na Nonane 0.28 [+ or -] 0.51 Decane 2.88 [+ or -] 0.45 Undecane 12.26 [+ or -] 1.03 Do decane 3.30 [+ or -] 0.65 Tridecane 2.27 [+ or -] 0.57 Tetradecane 0.72 [+ or -] 0.46 Pentadecane 0.49 [+ or -] 0.27 Hexadecane 0.37 [+ or -] 0.73 Heptadecane 0.78 [+ or -] 0.32 Octadecane 0.25 [+ or -] 0.18 Nonadecane 1.02 [+ or -] 1.34 Eicosane 1.19 [+ or -] 1.24 Nonanoic acid na Decanoic acid na Undecanoic acid na Dodecanoic acid na Tridecanoic acid na Tetradecanoic acid na Pentadecanoic acid na Hexadecanoic acid na Hept a decanoic acid na Octadecanoic acid na Ethyl, Benzene <0.1 p-,m-Xylene 0.15 [+ or -] 0.05 o-Xylene 0.13 [+ or -] 0.06 Styrene 0.24 [+ or -] 0.14 isopropyl, Benzene 0.05 [+ or -] 0.05 n-Propyl, Benzene 0.03 [+ or -] 0.05 1,2,4-triMethyl- 0.07 [+ or -] 0.04 Benzene 1,3,5- triMethyl-Benzene 0.20 [+ or -] 0.07 sec-Butyl-Benzene nd 2,isopropyl, Toluene 0.03 [+ or -] 0.03 n-Butyl, Benzene nd Naphthalene 1.99 [+ or -] 0.09 Acenaphthene <0.009 Fluorene 0.06 [+ or -] 0.03 Phenanthrene 0.06 [+ or -] 0.04 Anthracene nd Fluoranthene <0.04 Pyrene 0.03 [+ or -] 0.10 FU3-PL-21- Compound TiG3 Tutafi pH 3.65 Mg 0.8 TOC 0.304 Formate <LOQ Acetate 1067.3 Nonane 1.52 [+ or -] 0.52 Decane 9.18 [+ or -] 0.56 Undecane 20.48 [+ or -] 1.66 Do decane 4.00 [+ or -] 0.69 Tridecane 1.06 [+ or -] 0.54 Tetradecane 0.72 [+ or -] 0.46 Pentadecane 0.62 [+ or -] 0.27 Hexadecane 0.65 [+ or -] 0.74 Heptadecane 1.10 [+ or -] 0.33 Octadecane 0.47 [+ or -] 0.18 Nonadecane 1.10 [+ or -] 1.33 Eicosane 1.25 [+ or -] 1.24 Nonanoic acid 2.86 [+ or -] 2.45 Decanoic acid 1.09 [+ or -] 1.64 Undecanoic acid 0.35 [+ or -] 0.20 Dodecanoic acid 1.45 [+ or -] 0.49 Tridecanoic acid 0.31 [+ or -] 0.19 Tetradecanoic acid 1.42 [+ or -] 0.31 Pentadecanoic acid 1.02 [+ or -] 0.29 Hexadecanoic acid 6.09 [+ or -] 1.34 Hept a decanoic acid 2.87 [+ or -] 0.59 Octadecanoic acid 9.19 [+ or -] 2.86 Ethyl, Benzene nd p-,m-Xylene 0.11 [+ or -] 0.05 o-Xylene 0.06 [+ or -] 0.05 Styrene 0.37 [+ or -] 0.14 isopropyl, Benzene 0.09 [+ or -] 0.05 n-Propyl, Benzene 0.03 [+ or -] 0.04 1,2,4-triMethyl- 0.08 [+ or -] 0.04 Benzene 1,3,5- triMethyl-Benzene 0.13 [+ or -] 0.06 sec-Butyl-Benzene nd 2,isopropyl, Toluene 0.05 [+ or -] 0.03 n-Butyl, Benzene 0.03 [+ or -] 0.03 Naphthalene 1.19 [+ or -] 0.06 Acenaphthene <0.009 Fluorene 0.09 [+ or -] 0.03 Phenanthrene 0.23 [+ or -] 0.05 Anthracene nd Fluoranthene 0.05 [+ or -] 0.16 Pyrene 0.09 [+ or -] 0.10 FU3-PL- Compound 20-TiGl Tutafi pH 4.14 Mg 0.7 TOC na Formate na Acetate na Nonane 2.29 [+ or -] 0.54 Decane 22.16 [+ or -] 0.95 Undecane 26.93 [+ or -] 2.21 Do decane 5.14 [+ or -] 0.76 Tridecane 1.42 [+ or -] 0.54 Tetradecane 0.70 [+ or -] 0.46 Pentadecane 0.58 [+ or -] 0.27 Hexadecane 0.48 [+ or -] 0.73 Heptadecane 0.98 [+ or -] 0.32 Octadecane 0.50 [+ or -] 0.19 Nonadecane 1.36 [+ or -] 1.35 Eicosane 1.50 [+ or -] 1.26 Nonanoic acid 9.90 [+ or -] 3.21 Decanoic acid 0.83 [+ or -] 1.66 Undecanoic acid 0.33 [+ or -] 0.19 Dodecanoic acid 0.61 [+ or -] 0.48 Tridecanoic acid 0.27 [+ or -] 0.20 Tetradecanoic acid 1.07 [+ or -] 0.32 Pentadecanoic acid 0.77 [+ or -] 0.29 Hexadecanoic acid 5.59 [+ or -] 1.32 Hept a decanoic acid 2.79 [+ or -] 0.57 Octadecanoic acid 9.66 [+ or -] 2.96 Ethyl, Benzene 0.44 [+ or -] 0.23 p-,m-Xylene 0.71 [+ or -] 0.08 o-Xylene 0.68 [+ or -] 0.09 Styrene 0.20 [+ or -] 0.14 isopropyl, Benzene 0.09 [+ or -] 0.05 n-Propyl, Benzene 0.04 [+ or -] 0.04 1,2,4-triMethyl- 0.07 [+ or -] 0.04 Benzene 1,3,5- triMethyl-Benzene 0.19 [+ or -] 0.06 sec-Butyl-Benzene 0.07 [+ or -] 0.05 2,isopropyl, Toluene 0.07 [+ or -] 0.03 n-Butyl, Benzene 0.03 [+ or -] 0.03 Naphthalene 1.19 [+ or -] 0.06 Acenaphthene <0.009 Fluorene 0.07 [+ or -] 0.03 Phenanthrene 0.17 [+ or -] 0.05 Anthracene nd Fluoranthene <0.04 Pyrene 0.06 [+ or -] 0.10
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|Title Annotation:||Research Article|
|Author:||Konn, C.; Donval, J.P.; Guyader, V.; Roussel, E.; Fourre, E.; Jean-Baptiste, P.; Pelleter, E.; Charl|
|Date:||Jan 1, 2018|
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