Geology of the Grand Calumet River region.

ABSTRACT

The geology of the Calumet River region is briefly reviewed to provide a background for applied research in the area. The review relies heavily upon research conducted by scientists affiliated with the Indiana and Illinois Geological Surveys. At the end of the Late Wisconsinan glacial epoch, fluctuations in the Lake Michigan Lobe of the Laurentide Ice Sheet resulted in the formation of three moraine systems around the south end of the Lake Michigan basin: in decreasing age, the Valparaiso, Tinley and Lake Border ridges. High stands of ancestral Lake Michigan (also known as glacial Lake Chicago) are named the Glenwood, Calumet and Algonquin high phases that formed when the north end of the basin was blocked by ice. Retreat of the glacier from the basin caused the lake level to drop during the Two Creek low phase. The Chippewa low occurred at the beginning of the Holocene when ancestral Lake Michigan was as much as 107 m below modern levels. Lake level then rose in response to isostatic rebound of the outlet in southern Ontario until the Nipissing high was reached about 5000 years ago. At this time, the Toleston Beach in northern Indiana and Illinois was developing as a complex of sand dunes and more than 100 beach ridges. The Grand Calumet River came into existence about 2600 years ago as spits deflected the Little Calumet River eastwards upon closure of the Sag channel. Eastward migration of the Grand Calumet River ceased when the coastline was modified following European settlement in the late 19th century.

Keywords: Indiana, Lake Michigan, Grand Calumet River, geology

**********

The geology of the Grand Calumet River region (hereafter referred to as 'the region') is closely tied to glacial events that began about 1,600,000 years ago. During the Pleistocene epoch ([approximately equal to]1,600,000-10,000 years ago) the region was impacted by numerous glacial advances and retreats. Because successive glacial advances destroyed the evidence of previous advances, the number of glaciations is unknown. The presence of older glacial sediment throughout the Midwest beyond the limit of the late Wisconsinan glaciation (Fig. 1), which peaked about 20,000 years ago (Mickelson et al. 1983), is testament to earlier, more extensive glaciations. In the region there appears to be sedimentary evidence for only the most recent glacial episode (Brown et al. 1996), although there may be some uncertainty about this. The geology of the region is by no means only a result of glacial erosion and sedimentation. Much of the sediment in the region was deposited as littoral sand or offshore mud from various leve ls of glacial Lake Chicago and mid-Holocene age Lake Michigan. The variable levels of these lakes developed in response to the presence of ice in the Lake Michigan basin and isostatic rebound in Ontario.

Time (radiocarbon dates) within the text older than 6300 ybp (years before present [1950]) is in radiocarbon years, while dates younger than 6300 ybp are reported in calendar ybp.

GLACIAL AND GLACIAL LAKE HISTORY

The region is underlain by sediment deposited by glaciers and glacial lakes. The Grand Calumet River is located on lacustrine sediment of the Toleston Beach that is less than 6300 years old, which in turn lies upon older glacial, and finer-grained glaciolacustrine sediment. The distribution and character of this older sediment is best understood by linking the history of the recessional ice margin with glacial lakes in the Lake Michigan basin.

During the last ice age, known as the Wisconsinan in the Midwest, the Laurentide Ice Sheet advanced across much of Indiana, Illinois, and Ohio (Fig. 1); and the maximum extent of ice was reached about 20,000 ybp. Across Indiana, there are series of recessional moraines that record stationary ice-margins (Gray 1989) composed of glacigenic material (sand, gravel, and till). By about 14,000 ybp (Hansel et al. 1985) much of the Laurentide Ice Sheet was confined to the Great Lake basins, giving a lobate pattern to the ice margin (e.g., Fig. 2). The Valparaiso Moraine wraps around the southern end of Lake Michigan, extending into Michigan and Wisconsin; and in Indiana, the moraine forms the sub-continental drainage divide between the St. Lawrence and Mississippi drainage systems. Set inside the Valparaiso Moraine are two other recessional moraines known as the Tinley and Lake Border Moraines. All three ridges were likely deposited in a short period of time around 14,000 ybp by successive and less extensive readvanc es (Fig. 5). Glacial lakes formed between the ice and the ridges as the glacier receded northwards, opening up the lake basin. Because the glaciers were in lake basins, they rested on fine-grained sediment well-lubricated with water, and this low-resistive state (Clarke 1987) likely aided the glaciers ability to respond quickly to variations in climatic conditions and/or glaciologic controls. These responses are illustrated in Figs. 2-4, where four different positions of the ice margin are illustrated. The dated phases are averages and simplifications. For example, the Glenwood phase has been interpreted to consist of two separate advances with a low-lake phase between them (Hansel et al. 1985). Figures 2-4 are designed to provide the reader with only an overview of late-glacial events.

When the Lake Michigan lobe of the Laurentide Ice Sheet occupied the lake basin, the Straits of Mackinac were blocked by ice. Glacial Lake Chicago was dammed by the glacier (hence the term: glacial lake) and the outlet was located on the lowest point of the drainage divide (Leverett 1897). During the Glenwood phase (Fig. 2), the Chicago outlet was active, with water flowing through the Sag and Des Plains channels. Once the glacier receded northwards enough to deglaciate the Straits of Mackinac or Indiana River lowlands, lake level dropped and was controlled by outlets to the northeast (Hansel et al. 1985). The Chicago outlet was abandoned at this time, and forests grew on the newly exposed lake plain between the Glenwood shoreline and the much lower lake of the Two Creeks phase (Fig. 2). The northeast outlets were glaciated once more during a readvance of the Lake Michigan lobe, causing the lake to rise to the Calumet level. The rising lake buried a forest at Two Creeks, Wisconsin (Broecker & Farrand 1963) an d other woody material in the Chicago region (Hansel et al. 1985) and northwest Indiana (Schneider & Reshkin 1982; Schneider & Hansel 1990). The radiocarbon dates indicate flooding of the land started at about 11,800 ybp. The higher lake level is known as the Calumet phase, and the Chicago outlet was reoccupied (Fig. 3). By about 11,200 ybp the Lake Michigan lobe had begun to retreat northwards of the Straits of Mackinac, and Lakes Michigan and Huron were confluent. This lake is called glacial Lake Algonquin, and some contend that any evidence of it in the region was eroded by the subsequent mid-Holocene Nipissing high phase (Karrow 1980; Hansel et al. 1985). However, more recently Chrzastowski & Thompson (1994) and Capps et al. (2000) have described erosional scarps just below the Calumet level as evidence for an Algonquin beach in the region. With continued retreat of ice in southern Ontario, the North Bay outlet was exposed around 10,300 ybp (Larsen 1987). Ancestral Lake Michigan dropped to a low level kno wn as the Chippewa low (Fig. 4), which may have been as much as 107 m below the modern lake level (Hough 1955). More recently, Coleman et al. (1994) have suggested only an [approximately equal to]80 m lowering. At this time until the mid-Holocene, ancestral Lake Michigan drained through the North Bay outlet into the Ottawa River before entering the St. Lawrence east of Lake Ontario.

The distribution of the sediment deposited during ice recession was partly controlled by elevation. On Fig. 5, the diamond pattern indicates glacigenic sediment (tills, debris flows, sand and gravel, and ice-contact glacial lake sediment) of the Lake Border sequence (Tinley and Lake Border Moraines) and Valparaiso Megasequence (Brown et al. 1996). The Glenwood-age sediment consists of two main types. First, the most obvious landforms are the extensive spits that built across northwest Indiana by the westerly transport of sand by littoral currents. Although not shown on Fig. 5, Glenwood-age spits are prevalent in Illinois; and they indicate an easterly transport direction. The spits record migration of sand southward along both sides of the lake, focusing sediment to its southern end. The spits record a lake level between about 195-189 m suggesting that the Chicago outlet was slowly being eroded during Glenwood time. The second type of Glenwood sediment is fine-grained lacustrine sediment of laminated and mass ive silty-clay. This unit is mapped as part of the Lake Border sequence and consists of approximately 16 m of laminated clay, silt, and silty clay and fine-grained till over bedrock (Bleuer and Woodfield 1993; Brown & Thompson 1995; Brown et al. 1996).

There are no sediments mapped for the Two Creeks phase because the region was subaerially exposed at this time. It is during this time and the subsequent Chippewa phase that the region's rivers carved their valleys. This incision was in response to the lower lake level that increased the streams bed slope. Evidence for the low lake level is now beneath the lake. For example, divers off Chicago found a buried forest with oak stumps rooted in place beneath 25 m of water (Chrzastowski et al. 1991). Radiocarbon dates averaging 8300 ybp suggest that the lake had risen to that elevation by then and drowned the trees.

The next youngest sequence of sediment in the region is affiliated with the Calumet Phase. Two map units are shown on Fig. 5. Sand dunes form an arc parallel to, and south of, the Little Calumet River. On either side of the dunes, beach, lagoon, and shallow water, sand and mud is exposed at the surface today. The elevation of the lake was at approximately 189 m. Spits were also formed at this time, but are restricted to near the Illinois state line and further west. The Calumet-age sediment is grouped with the Glenwood dunes and littoral sediment as part of the Lake Michigan sequence because in the subsurface it is difficult to differentiate between Glenwood and Calumet sediment (S.E. Brown pers. commun. 2002).

HOLOCENE CHANGES IN SOUTHERN LAKE MICHIGAN

Previously, the fluctuations in glacial Lake Chicago were explained by fluctuations in the ice margin of the Lake Michigan lobe: but interestingly, after the Lake Michigan lobe had retreated well north of the Great Lakes, the effect of the ice sheet was still felt in the Lake Michigan basin. A time lag exists between deglaciation and when the Earth's crust has reached its equilibrium elevation once the ice sheet load had been removed (slow isostatic rebound). As mentioned earlier for the Two Creeks phase, during the Chippewa phase, the outlet for the Great Lakes was the North Bay outlet rather than the modern outlet at Port Huron. During the Holocene, the North Bay outlet gradually rose causing Lakes Michigan and Huron to rise until they were confluent with Lake Superior (Larsen 1985). Lake Michigan continued to rise until it reached two peaks at approximately 5300 (Larsen 1994) and 4700 ybp (Baedke & Thompson 2000) known as the Nipissing I and II high phases, respectively (Fig. 4). During the Nipissing phase the North Bay, Sag channel outlet (Chicago outlet), and Port Huron outlets were simultaneously active (Lewis 1969, 1970). With continued isostatic rebound, the North Bay outlet was abandoned; and there may have been a rapid drop in lake level that could be attributed to incision of the Port Huron outlet (Baedke & Thompson 2000). At around 2600 ybp the Sag channel was abandoned (Chrzastowski & Thompson 1992) leaving the Port Huron outlet as the sole outlet.

Since about 6300 ybp (Thompson & Baedke 1997), when the lake rose above the modern lake level from the Chippewa low to the Nipissing high, the 700 [km.sup.2] Toleston Beach began forming. A lake level curve going back to 4700 ybp was reconstructed based on the elevation of foreshore gravel deposits in beach ridges from the Lake Michigan basin since the Nipissing high (Baedke & Thompson 2000). Beach ridges record the high elevation of fluctuations in lake level, thus the curve (Fig. 6) is a smoothed record of high lake levels from the last 4700 years. It is interesting to note that Thompson (1992) and Thompson & Baedke (1995, 1997) were able to determine three scales of lake level fluctuations. There are 25-35, 140-160, and 500-600 yr cycles with a lake level elevation change of 0.5-0.6, 0.8-0.9, and 1.8-3.7 m, respectively.

The Toleston Beach has prograded basin-ward since the Nipissing high, and incorporates the Little and Grand Calumet Rivers. On Fig. 5 the Toleston-age sediment is shown in lightest gray. Sand dunes are stippled and dominate the eastern side of the Toleston Beach. The southern band of parabolic dunes had developed by 3200 ybp and point eastwards, reflecting westerly air flow. The younger, northern band of dunes contain parabolic dunes that point southeast and southwards recording a transition to more northerly air flow (Thompson 1992). Westward of the sand dunes, the Toleston Beach widens to where it contains over 100 beach ridges (Thompson & Baedke 1997).

The evolution of the Little and Grand Calumet Rivers is illustrated in Figs. 7-10 and was the result of three factors: 1) relative topographic gradients perpendicular to the shoreline, 2) littoral transport of sand from the northwest after about 3000 ybp, and 3) fluctuations in lake level. Along the eastern part of Fig. 5 the relative slope of the land into the off-shore zone is steeper than at the lake plain further west in the southwest corner of the lake. As a result, aeolian processes dominated, and dunes rather than beach ridges developed on the eastern side of the Toleston Beach. Further west, the southwest corner of the lake acted as a depositional sink; and beach ridges developed with only minor sand dune development.

Initially, the source of sand for most of the beach ridges in the Toleston Beach was from glacial deposits along the Michigan coastline. Bluff recession would have been particularly active during the rise in lake level from the Chippewa low to the Nipissing high. Recently, Loope & Arbogast (2000) demonstrated that the age of perched sand dunes along the western coast of Lower Michigan corresponds with high stands of Lake Michigan (see Fig. 6). Therefore, during these short-lived high stands, bluff recession would also increase sand supply for littoral transport. The paleogeographic reconstruction of Fig. 7 corresponds in time to about the Nipissing II peak. The lake has flooded the Sag Channel and the Calumet lagoon formed behind the early Toleston beach. Since the Nipissing II high, there was only westerly transport of sand to the southern end of the lake where beach ridges developed. The easterly transport of the sand did not reach the region until after 3000 ybp because the Chicago outlet embayment was tra pping sediment (Chrzastowski & Thompson 1992). Figure 8 reflects a lowering of the lake level with continued beach and dune development. Note that by this time spits are building out from Stoney Island in Illinois across the outlet embayment, and beginning to deflect the Little Calumet River eastwards.

As the Calumet River turns east, it is referred to as the Grand Calumet River. Thus the Grand Calumet River came into existence just after 2600 ybp when the Sag Channel was abandoned (Chrzastowski & Thompson 1992). At about 1500 ybp all barriers to the south- and eastward transport of sand were removed (Fig. 9); and a large baymouth bar formed by spit growth, trapping an embayment of Lake Michigan to form Lake Calumet. The Grand Calumet River entered Lake Calumet and was then continually deflected eastwards by spit growth at the mouth of the river. At about 1100 ybp continued spit growth had captured another part of ancestral Lake Michigan to form Wolf Lake (Fig. 10). The spit growth corresponds to high stages in Lake Michigan between 2000 and 1000 ybp (Fig. 6) and presumably increased sediment supply. The Toleston Beach continued to grow northward into the lake as beach ridges developed once every [approximately equal to]30 years, while at the same time deflecting the Grand Calumet River further eastward. De velopment of the Toleston Beach had essentially stopped once European settlement in the area led to modification of the shoreline during the 19th and 20th centuries, although occasional beach ridges are still forming today on the eastern side of obstacles to littoral drift (Hunter et al. 1990). Shoreline positions for selected dates are superimposed on Fig. 10.

Sediments that underlie the region have been investigated by numerous researchers (Blueur & Woodfield 1993; Doss 1993; Brown & Thompson 1995; Brown et al. 1996). Beneath Lakes Calumet and Wolf, and the Grand Calumet River are 15-18.5 m of sand, gravel, and peat (Doss 1993) of the Lake Michigan sequence that is in turn underlain by finer grain sediment of the Lake Border sequence (Brown et al. 1996). Sand is the predominate sediment in the Toleston Beach, with minor amounts of gravel in the beach ridges; and organic material (peats) is found in swales between beach ridges and in the Calumet lagoon.

SUMMARY

The geology of the region is linked to the events of deglaciation and subsequent fluctuations in the levels of ancestral Lake Michigan. Glacial sediment of the Lake Border sequence and Valparaiso megasequence consists of tills and meltwater deposits from ice-marginal environments in the southern part of the region above 195 m elevation. Sometime around 14,000 ybp the glacier had receded northwards from Indiana and glacial Lake Chicago occupied the region in which finegrained lacustrine sediment and spits were deposited during the Glenwood phase. Lake level dropped for about 500 years during the Two Creeks low phase until ice once again dammed the north end of the basin and the lake rose to the Calumet high phase, when another sandy beach with dunes formed. The lake dropped to the Chippewa low after final deglaciation of the Straits of Mackinac and North Bay outlet in Ontario. During the Chippewa phase when the lake was from 80-107 m lower than today, rivers eroded their valleys in the region in response to st eeper streambed gradients. With the isostatic rise of the North Bay outlet, Lake Michigan became confluent with Lakes Superior and Huron during the Nipissing high; and the Port Huron outlet became the controlling outlet following abandonment of the North Bay and Chicago outlets. During the rise to the Nipissing high, the Toleston Beach began developing by 6300 ybp. The beach is dominated by sand dunes on its eastern edge and by more than 100 beach ridges further west where the Toleston Beach is up to 10 km wide. The Grand Calumet River developed once the Little Calumet River was deflected eastwards by spits at about 2600 ybp. Spits and beach ridges continued to grow until the end of the 19th century, which resulted in (1) capturing small embayments of Lake Michigan to form Calumet and Wolf Lakes, and (2) further deflecting of the Grand Calumet River eastward.

[FIGURE 6 OMITTED]

ACKNOWLEDGMENTS

This review paper has relied heavily upon the work by past researchers, in particular geologists affiliated with the Indiana and Illinois Geological Surveys. The forthcoming book Calumet Area Beginnings by Ken Schoon to be published by the Indiana University Press describes the history of the region since settlement and the affiliated changes to the landscape. Thanks to Ken who graciously allowed me access to a draft of his book when I was writing this article while on sabbatical leave in New Zealand. This review paper has benefited from the many discussions over the last eight years with Steve Brown of the Indiana Geological Survey who has provided information and maps in an efficient and unhesitating manner. An anonymous reviewer has improved the clarity of the manuscript. Lastly, I wish to acknowledge the Department of Geography at the University of Canterbury in New Zealand for support whilst I was writing this paper.

LITERATURE CITED

Baedke, S.J. & T.A. Thompson. 2000. A 4,700-year record of lake level and isostasy for Lake Michigan. Journal of Great Lake Research 26: 416-426.

Bleuer, N.K. & M.C. Woodfield. 1993. Glacial terrain, sequences, and aquifer sensitivity, Porter County, Indiana. Indiana Geological Survey Open-File Report 93-2. 90 pp.

Broecker, W.S. & W.R. Farrand. 1963. Radiocarbon age of the Two Creeks forest bed, Wisconsin. Geological Society of America Bulletin 74: 795-802.

Brown, S.E. & T.A. Thompson. 1995. Geologic terrains of the Chicago 30 X 60-minute quadrangle in Indiana: Indiana Geological Survey Open-File Map 95-09.

Brown, S.E., Bleuer, N.K. & T.A. Thompson. 1996. Geologic terrain map of the Southern Lake Michigan Rim: Indiana Geological Survey Open-File Study 96-13, 1:100,000-scale map plus 50 page explanation.

Capps, D.K., T.A. Thompson, J.W. Johnston & S.R. Jock. 2000. An Algonquin shoreline in southern Lake Michigan. Geological Society of America, North-Central Section, 35th annual meeting, Geological Society of America Abstract with Program 33(4):47.

Chrzastowski, M.J., F.A. Pranschke & C.W. Shabica. 1991. Discovery and preliminary investigations of the remains of an early Holocene forest on the floor of southern Lake Michigan. Journal of Great Lakes Research 17:543-552.

Chrzastowski, M.J. & T.A. Thompson. 1992. The late Wisconsinan and Holocene coastal evolution of the southern shore of Lake Michigan. Society of Economic Petrology and Mineralogy Special Publication 48:397-413.

Chrzastowski, M.J. & T.A. Thompson. 1994. Late Wisconsinan and Holocene Geologic History of the Illinois-Indiana Coast of Lake Michigan. Journal of Great Lakes Research 20:9-26.

Clarke, G.K.C. 1987. Fast glacier flow: ice streams, surging and tidewater glaciers. Journal of Geophysical Research 92:8835-8841.

Coleman, S.M., R.M. Forester, R.L. Reynolds, D.S. Sweetkind, J.W. King, P. Gangemi, G.A. Jones, L.D. Keigwin & D.W. Foster. 1994. Lake-level history of Lake Michigan for the past 12,000 years: the record from deep lacustrine sediments. Journal of Great Lakes Research 20:73-92.

Doss, P.K. 1993. The nature of a dynamic water table in a system of non-tidal, freshwater coastal wetlands. Journal of Hydrology 141:107-126.

Eschman, D.F & P.F. Karrow. 1985. Huron basin glacial lakes: A review. Pp. 79-94, In Quaternary Evolution Of The Great Lakes. (P.F. Karrow & P.E. Calkin, eds.). Geological Association of Canada, Special Paper 30.

Gray, H.H. 1989. Quaternary Geologic Map of Indiana. Indiana Geological Survey Miscellaneous Map 49, Scale 1:500,000.

Hansel, A.K., D.M. Mickelson, A.F. Schneider & C.E. Larsen. 1985. Late Wisconsinan and Holocene history of the Lake Michigan basin. Pp. 39-54, In Quaternary Evolution Of The Great Lakes. (P.F. Karrow & P.E. Calkin, eds.). Geological Association of Canada, Special Paper 30.

Hough, J.L. 1955. Lake Chippewa, a low stage of Lake Michigan indicated by bottom sediments. Geological Survey of American Bulletin 66:957-968.

Hunter, R.E., T.E. Reiss, J.L. Chin & R.J. Anima. 1990. Coastal depositional and erosional effects of the 1985-1987 high lake levels in Lake Michigan. United States Geological Survey Open-file Report 90-272. 9 pp.

Karrow, P.F. 1980. The Nipissing transgression around southern Lake Huron. Canadian Journal of Earth Sciences 17:1271-1274.

Larsen, C.E. 1985. Lake level, uplift, and outlet incision, the Nipissing and Algoma Great Lakes. Pp. 63-77, In Quaternary Evolution Of The Great Lakes. (P.F. Karrow & P.E. Calkin, eds.). Geological Association of Canada, Special Paper 30.

Larsen, C.E. 1987. Geological history of glacial Lake Algonquin and the upper Great Lakes. United States Geological Survey Bulletin 1801.

Larsen, C.E. 1994. Beach ridges as monitors of isostatic uplift in the upper Great Lakes. Journal of Great Lakes Research 20:108-134.

Lewis, C.F.M. 1969. Late Quaternary History of the lake levels in the Huron and Erie basins. Pp. 250-270, In Proceedings 12h Conference On Great Lakes Research, International Association for Great Lake Research.

Lewis, C.F.M. 1970. Recent uplift of Manitoulin Island, Ontario. Canadian Journal of Earth Sciences 7:665-675.

Leverett, F. 1897. The Pleistocene features and deposits of the Chicago area. Chicago Academy of Science Bulletin 2. 86 pp.

Loope, W.L. & A.F. Arbogast. 2000. Dominance of an [approximately equal to]150-year cycle of sand-supply change in late Holocene dune-building along the eastern shore of Lake Michigan. Quaternary Research 54:414-422.

Mickelson, D.M., L. Clayton, D.S. Fullerton & H.W. Borns. 1983. The late Wisconsin glacial record of the Laurentide Ice Sheet in the United States. Pp. 3-37, In Late-Quaternary Environments Of The United States, Volume 1, The Late Pleistocene. (H.E. Wright & S.C. Porter, eds.). University of Minnesota Press, Minneapolis.

Schneider, A.F. & M. Reshkin. 1982. Identification of the Twocreekan Substage in Indiana. Proceedings of the Indiana Academy of Science 91, p. 347.

Schneider, A.F. & A.K. Hansel. 1990. Evidence for post-Two Creeks age of the type Calumet shoreline of glacial Lake Chicago. Pp. 1-8, In Late Quaternary History Of The Lake Michigan Basin. (A.F. Schneider & G.S. Fraser, eds.). Geological Society of America Special Paper 25.

Thompson, T.A. 1992. Beach-ridge development and lake-level variation in southern Lake Michigan. Sedimentary Geology 80:305-318.

Thompson, T.A. & S.J. Baedke. 1995. Beach-ridge development in Lake Michigan: shoreline behavior in response to quasi-periodic lake-level events. Marine Geology 129:163-174.

Thompson, T.A. & S.J. Baedke. 1997. Strand-plain evidence for late Holocene lake-level variations in Lake Michigan. Geological Survey of American Bulletin 109:666-682.