page_title: Thomas Gold
section_title: Drilling in Siljan
hierarchical_section_title: Thomas Gold / Origins of petroleum / Drilling in Siljan
caption_attribution_description: Siljan impact crater. Several lakes trace the remnants of the eroded impact crater that was formed by a meteorite impact about 370 million years ago. With a diameter of 55 km it is the largest impact structure in Europe. Lake Siljan is the large lake in the south of the ring.
context_page_description: Thomas Gold, was an Austrian-born astrophysicist, a professor of astronomy at Cornell University, a member of the U.S. National Academy of Sciences, and a Fellow of the Royal Society. Gold was one of three young Cambridge scientists who in 1948 proposed the now mostly abandoned "steady state" hypothesis of the universe. Gold's work crossed academic and scientific boundaries, into biophysics, astronomy, aerospace engineering, and geophysics.
context_section_description: Gold began testing his theory in 1986 when, with the backing of a group of investors, Vattenfall and the Gas Research Institute, he commenced efforts to drill a deep borehole – named Gravberg-1 – into the earth near Lake Siljan in search of abiogenic gas in the mantle. The region was the site of a large meteor crater, which would have "opened channels deep enough for the methane to migrate upward" and formed deposits in caprock just a few miles beneath the surface. He estimated that the fractures near Lake Siljan reached down nearly 40 kilometres (25 mi) into the earth.
  In 1987, approximately 900 barrels (140 m³) of drilling lubricant disappeared nearly 20,000 feet (6,100 m) into the ground, leading Gold to believe that the lubricant had fallen into a methane reservoir. Soon after, the team brought up nearly 100 liters of black oily sludge to the surface. Gold claimed that the sludge contained both oil and remnants of archaebacteria. He argued that "it suggests there is an enormous sphere of life, of biology, at deeper levels in the ground than we have had any knowledge of previously" and that this evidence would "destroy the orthodox argument that since oil contains biological molecules, oil reserves must have derived from biological material". The announcement of Gold's findings was met with mixed reactions, ranging from "furious incredulity" to "deep skepticism". Geochemist Geoffrey P. Glasby speculated that the sludge could have been formed from the Fischer–Tropsch process, a catalyzed chemical reaction in which synthesis gas, a mixture of carbon monoxide and hydrogen, is converted into liquid hydrocarbons. Critics also dismissed Gold's archaebacteria finding, stating that "since micro-organisms cannot survive at such depth, the bacteria prove that the well has been contaminated from the surface". Geochemist Paul Philp analyzed the sludge and concluded that he could not differentiate between the samples of sludge and oil seep found in sedimentary shale rocks near the surface. He reasoned that oil had migrated from the shale down to the granite deep in the ground. Gold disputed Philp's finding, believing that the oil and gas could have just as easily migrated up to the surface: "They would have it that the oil and gas we found down there was from the five feet of sediments on the top – had seeped all the way down six kilometres down into the granite. I mean, such complete absurdity: you can imagine sitting there with five feet of soil and six kilometres underneath of dense granitic rock, and that methane produced up there has crawled all the way down in preference to water. Absolute nonsense."
  In light of the controversy surrounding the sludge and possible drill contamination, Gold abandoned the project at Gravberg-1, calling it a "complete fiasco", and redesigned the experiment by replacing his oil-based drilling lubricant with a water-based one.
  The drill hit oil in the spring of 1989, but only collected about 80 barrels (13 m³). Gold stated, "It was not coming up at a rate at which you could sell it, but it showed there was oil down there." The drill then ran into technical problems and was stopped at a depth of 6.8 kilometres (4.2 mi). The hole was closed, but a second hole was opened for drilling closer to the "center of the impact ring where there was even less sedimentary rock". By October 1991, the drill hit oil 3.8 kilometres (2.4 mi) into the ground, but many skeptics remained unconvinced of the site's prospects. One skeptic, Christer Akerman, the chief geologist of the Geological Survey of Sweden, remarked, "[t]here is every reason to stay calm and await the analysis of what they have found. The point is also that they will have to find commercially viable amounts, and it may be a long time before we know if they do." Geologist John R. Castaño concluded that there was insufficient evidence of the mantle as the hydrocarbon source and that it was unlikely that the Siljan site could be used as a commercial gas field. Some skeptics countered Gold's claims by suggesting that the oil found was actually contaminat
caption: Sweden's Lake Siljan is a large lake created from an eroded impact crater, the Siljan Ring, that was formed by a meteorite impact about 370 million years ago. It was at this lake that Gold proposed as the most likely place to test the hypothesis on the origin of petroleum because it was one of the few places in the world where the granite basement was cracked sufficiently to allow oil to seep up from the mantle.
exif: {}