How oil is formed:
<<http://www.gasresources.net/DisposalBioClaims.htm Long ago in 1981 I came up with a theory on how oil is really produced. It has still not been falsified.
I had noticed that ophiolites were correlated with oil deposits, just by coincidence when looking at a geological map and with a BP book on oil deposits around the world.
Correlation is not causation, but it's a really good start, especially when the correlation was pandemic and pretty much complete.
History of plate tectonics here: ucmp.berkeley.edu
Scientific American had done an article about ophiolites. BP had a book on oil fields [among other things]. So I put the two together. Sure enough, a great match.
So my next problems were, how does that work and how do I get rich? I figured I was not far off stupendous wealth as an oil explorer.
It works like this.
Phytoplankton, fish, mammals, and everything else live in the oceans with materials washed down rivers into the ocean and CO2 coming in from the air. When they die, some buoyant parts are recycled, but plenty is buried in kilometres of sediment on the oceanic crust.
They are trundled along on the oceanic crust due to plate tectonics and plunged down in subduction zones into the hot interior 200 km underground.
With the pressure and temperature there, the sedimentary layers are cooked and the organic material floats off upwards, ending up trapped in sedimentary layers, leaking out through the surface, or acting as the fuel to propel volcanic eruptions to the sky.
If that theory is not correct, some explanation is required on what happened to all that subducted organic material. There are not volcanoes sufficient to recycle all of it.
My problem then was to figure out where to find these oil and gas deposits. That was where it got too hard. The ophiolites provided a good general location method, but digging a well needs to be precise.
What matters is the shape of the melt zone way down and the way in which the organics float to the sedimentary traps. Then, seismic work is needed to find those traps. It all got too hard. But I have one area in Northland [NZ] where I think it would be worth drilling a well or two.
Here's some good background information on oceanic processes:
britannica.com
As you can see from the first paragraph, oceanic sediment varied a lot, so the subduction of organic material varied a lot and therefore the production of oil and gas deposits varied a lot.
< During the time interval between 200 and 65 million years ago, but especially from 100 to 65 million years ago, microplankton abundance and diversity increased enormously in the oceans. This resulted in increased deposition of biogenic sediments in the ocean basin. During Cretaceous time (from 144 to 66.4 million years ago), sea level was often high, and shallow seas lapped onto the continents. This may have provided an environment favourable to the explosion in the numbers of species of foraminiferans, diatoms, and calcareous nannoplankton. Increased abundance of calcareous nannoplankton shifted the locus of carbonate sedimentation from shallow seas to the deep ocean. The end of Cretaceous time is marked by a sudden extinction of many life-forms on Earth, and marine organisms were no exception (see Cretaceous Period). Coccolithophores (calcareous nannoplankton) and planktonic foraminiferans were particularly affected, and only a few species survived. Ocean sediments were suddenly less biogenic, and clays became widespread.
After Cretaceous time the Earth underwent a gradual cooling, especially at high latitudes. Deep-sea sedimentation changed as thermohaline bottom water circulation became fully developed (see above Circulation of the ocean waters: Thermohaline circulation). The CCD rose in the Pacific and dropped in the Atlantic as a result of changes in thermohaline circulation. An event of major significance was the spreading away of Australia from Antarctica beginning about 53 million years ago. This separation initiated limited circum-Antarctic circulation, which isolated Antarctica from the warmer oceans to the north, and led to cooling, which set the stage for later major glaciation.
At the Eocene-Oligocene boundary (36.6 million years ago), Antarctic Bottom Water began to form, resulting in greatly decreased bottom-water temperatures in both the Pacific and Atlantic oceans. Bottom-living organisms were strongly affected, and the CCD suddenly dropped from about 3,500 metres to approximately 4,000 to 5,000 metres in the Pacific. Bottom-water temperatures were generally warm, 12° to 15° C, during the time preceding this event. In a study of deep-sea sediment core material from near Antarctica, J.P. Kennett and Lowell D. Stott of the United States discovered that there was a period between roughly 50 and 35 million years ago when deep waters were very warm (20° C) and salty. The origin of these ocean waters was most likely in the low latitudes and resulted from high evaporation rates there.
The modern oceans are distinguished by very cold bottom water. The gradual changes toward this condition began 10 million years after the origination of Antarctic Bottom Water. Particularly significant among these changes was the closing of the Tethys seaway as Australia and several microcontinents moved north into the Indonesian region. Also, Australia moved far enough north that circum-Antarctic surface circulation became fully established.
The modern ocean circulation patterns and basin shapes were mostly in place by the beginning of Miocene time (nearly 24 million years ago). An exception was an ocean connection between the Pacific and Caribbean Sea in Central America that persisted until about 3 million years ago. Major and probably permanent ice sheets on Antarctica formed during Miocene time, and glacial sediments began to dominate the seafloor surrounding the continent shortly thereafter. Siliceous oozes also became widespread around Antarctica. Siliceous sedimentation increased in this area at the expense of siliceous sedimentation in equatorial regions. Ocean circulation became more vigorous, global climate became cooler, and sedimentation rates in the ocean basins increased. Planktonic microorganisms were segregated into latitudinal belts. Bottom-water flow north through the Drake Passage between South America and Antarctica began in Miocene time, resulting in erosion and nondeposition of sediments in the southwest Atlantic and southeast Pacific oceans. Also during Miocene time rifting between Greenland and Europe had progressed to a point where a connection was established between the North Atlantic and the Norwegian Sea. This resulted in the formation of North Atlantic Deep Water (see above Circulation of the ocean waters: Thermohaline circulation), which began flowing south along the continental rise of North America at this time. Sediments redistributed and deposited by this deep current are called contourites and have been extensively studied by Bruce Heezen, Charles D. Hollister, and Brian E. Tucholke, among others.
Sudden global cooling set in near the end of the Miocene some 6 million years ago. The strength of ocean circulation must have increased, as evidence of increased upwelling and biological productivity is present in ocean sediments. Diatomaceous sediments were deposited in abundance around the rim of the Pacific. This cooling event is synchronous with a drop in sea level, thought to be about 40 or 50 metres by various authorities, and probably corresponds to the further growth of the Antarctic ice sheet. This lowered sea level, coupled with the closure of narrow seaways probably due to plate movements, isolated the Mediterranean Sea. Subsequently, the sea dried up, leaving evaporite deposits on its floor. The Swiss geologist Kenneth J. Hsü and the American oceanographer William B.F. Ryan have concluded that the Mediterranean probably dried up about 40 times as seaways opened and closed between 6 and 5 million years ago. This evaporation removed about 6 percent of the salt from the world ocean, which raised the freezing point of seawater and promoted further growth of the sea ice surrounding Antarctica.
Enormous ice sheets emerged in the Northern Hemisphere between 3 and 2 million years ago, and the succession of Quaternary glaciations began at 1.6 million years ago. The exact cause of the glacial period is unclear, but it is most likely related to the variability in solar isolation, increased mountain building, and an intensification of the Gulf Stream at 3 million years ago due to the closing off of the Pacific-Caribbean ocean connection in Central America. The Quaternary glaciations, of which there were probably 30 episodes, left the most dramatic record in ocean sediments of any event in the previous 200 million years. Terrigenous sedimentation rates greatly increased in response to fluctuations in sea level of up to 100 metres and a more extreme climate. Biogenic sedimentation also increased and fluctuated with the glacial episodes. Deep-sea erosion began in many places as a result of intensified bottom-water circulation. >>
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