Is there oil beneath your feet? Petroleum products are usually deemed "fossil fuels," created from once-living organisms. But oil may be a renewable resource that is literally beneath everyone's feet.

abiotic (a'bi at'ik): adj. Originating from sources other than biological materials such as plants, animals, or other formerly living organisms.

Two illustrations from my junior and senior high-school science textbooks have stuck in my mind for some 50 years. The first was a drawing of a German shepherd-sized horse with graphics demonstrating how this tiny equine evolved by biologic stages into today's large "modern" horse. The second memorable diagram showed multiple strata of the Earth's crust with dinosaurs and plants being converted into petroleum by the pressure and heat of compression from layers of rocks and soil that had somehow built-up miles above their remains.

Years later, in a long-forgotten source, the first of these images was tarnished by an article reporting that archeologists had determined that the smaller horses were in fossil formations considered to be of a later date than modern steeds. And now the second of my long-held high-school beliefs is being challenged by a number of geologists and planetary scientists. They don't believe oil is a product from the conversion of biotic (once-living) sources, but is an ongoing process occurring continuously deep within our planet--a region described by the late astrophysicist Thomas Gold * in his book of the same title: The Deep Hot Biosphere.

The Abiotic Theory

The conversion of carbon and hydrogen into molecules of various hydrocarbons is thought, by those theorists who support abiotic oil formation, to be possible only at extreme depths, approximately 60 miles--which is an order of magnitude deeper than present technology can examine directly. Here, according to abiotic theorists, carbon and hydrogen are combined to form methane, which in turn forms the multitude of hydrocarbon chains we know as petroleum. Being lighter than the surrounding rock, the hydrocarbons are buoyed up toward the surface, but are usually stopped by an impenetrable layer we call bedrock. There they may accumulate indefinitely until a fissure occurs, allowing a continuation of their rise toward the surface where they then often pool in sedimentary rock.

One of the causes of fissures is the impact of asteroids or comets, such as that causing the Chicxulub Crater on the Yucatan peninsula in Mexico and often associated with the extinction of the dinosaurs. This collision fractured the bedrock in the Gulf of Mexico in an area where major oil fields have been found, including the second largest on Earth, the Cantarell Field, discovered in 1976 by a fisherman of that name who thought he was over a sunken boat leaking fuel oil.

Similarly, the bedrock beneath Saudi Arabia is seriously fractured. Abiotic theorists claim the evidence shows the major oil fields in that country are directly over the fissure lines.

Not a New Theory

In 1757, Russian scholar Mikhail Lomonossov formulated what became the predominant theory of "rock oil" (petroleum) formation, otherwise called fossil fuel:

   Rock oil originates as tiny bodies of
   animals buried in the sediments which,
   under the influence of increased temperature
   and pressure acting during
   an unimaginably long period of time,
   transform into rock oil.

This theory was challenged in the late 19th century by no less a scientist than Dmitri Mendeleev, whose formulation of the Periodic Table of the Elements is often considered the most important advance in the history of chemistry. He discounted Lomonossov's theory, asserting that there was not enough biological material in the sedimentary rock to produce the amount of petroleum thought to exist--and this was years before the magnitude of the Middle East and Gulf of Mexico oil fields was even imagined.

It is possible to see why Mendeleev believed this. Assuming the same composition as a human, a 20,000-pound dinosaur would have 3,600 pounds of carbon--so a Tyrannosaurus Rex would produce about 460 gallons, or just over 10 barrels, of oil. Known reserves of petroleum are at about 2 trillion barrels, so it would take 200 billion T. Rexes or some equal biomass to produce that equivalent in petroleum products.

The 1950s brought forth serious studies from Russian and Ukrainian scientists that resulted in what is known as the R-U Theory. An excerpt from one study gives the flavor of their research:

   The overwhelming preponderance
   of geological evidence compels the
   conclusion that crude oil and
   natural petroleum gas have no intrinsic connection
   with biological matter originating
   near the surface of the Earth.
   They are primordial materials which
   have been erupted from great depths.

Since then the Soviets, and now the Russians, have put their money where their theories are and, while details are sketchy, have reportedly been highly successful in developing oil fields where many petroleum geologists fear to tread.

No Lack of Controversy

It would seem that the abiotic theory could be easily proven or disproven by drilling in areas of volcanic and other non-sedimentary bedrock where no plant or animal life ever existed. This indeed is what Thomas Gold convinced the Swedish State Power Board to spend $25 million doing.

In this case the bedrock had been fractured by an ancient asteroid or comet in an area where no surface life was ever present. While insufficient oil was found to be commercially viable, petroleum was indeed located where most geologists would consider its presence to be impossible. The London Telegraph quipped in its obituary for Dr. Gold that this was "ah achievement which ranked in the same league as getting blood from a stone."

The debate still rages between those advocating the "traditional" biological hypothesis and the R-U school, now referred to as the "modern" school. Traditionalists claim that biological markers and the ratio of C13 to C14 carbon isotopes are indicative of biologic origins. The latter would hold true because C14 is produced primarily by the action of solar radiation on atmospheric nitrogen, so anything with C14 was likely formed on the surface of the Earth.

The R-U advocates claim the markers are merely biological debris picked up as the hydrocarbons rise toward the surface and that the presence of helium in the oil is a sure sign of abiotic genesis. Their claim rests on the fact that a helium nucleus is also an alpha particle produced by radioactive decay. It is never found in biological materials. A controversy is raging, but eventually the truth will become known, as either there is oil below the bedrock or there isn't.

At present, however, successful drilling in areas heretofore considered barren of hydrocarbons will not be something to be announced to the world. Such knowledge, if true, would likely do fatal damage to the generally held belief that we are running out of oil--the primary reason OPEC members can charge $70 for a barrel of oil that can cost 50 cents to bring to the surface. And not just OPEC. Anyone with oil and gas leases, options, or mineral rights would have a period of adjustment if and when the current artificial price structure collapses.

But for the rest of humanity, low prices for energy from a renewable, portable, available, acceptable, well-understood source would be of inestimable value in improving our quality of life. This is particularly true for those who are lowest on the economic totem pole.

* Austrian Astrophysicist Thomas Gold's career began with perfecting radar during WWII. He was selected by Cornell University to head their Astronomy Department in 1959 and was elected to the National Academy of Sciences. He won the Gold Medal of the Royal Astronomical Society in 1985.