The hydrogen / carbon ratio, another proof of the mineral origin of hydrocarbons

In all oilfields and wells it is observed that the hydrogen / carbon ratio increases with depth, showing a loss of hydrogen as the fluid rises and approaches the surface.
For reasons of density, one would imagine that hydrogen-rich compounds, which are less dense, should be found in the upper strata, while hydrogen-poor substances, because they are heavier, should be in deeper zones.
However it is the other way around. The less dense compounds are down while the denser ones are above.
The only logical process that explains this trend of hydrocarbon deposits is the upward migration of hydrocarbons (due to planet degassing) and the separation (usually by preferential oxidation) of hydrogen versus carbon during flow.
T. Gold (2001) argues that this process is due in part to the action of bacteria that live at depth less than 10 km (hyperthermobacteria).
According to this approach, methane and other gases would be found in the lower layers, while heavier hydrocarbons (eg naphthas and liquid oils in general) would be located in the intermediate layers and bitumens and coals in the upper layers.
These processes are explained in more
detail in the following chapters.
From the book "Inexhaustible? Gas and Oil", by D.Anton, Piriguazú Ediciones

Cosmic and planetary abundance of carbon     
The element carbon (C) is the fourth in order of cosmological abundance, preceded only by hydrogen (H), helium (He) and oxygen (O). The available carbon in the nebula that gave rise to the solar system was built to Earth in the process of planetesimal accretion. The primary geochemical differentiation made heavier elements stay concentrated in the nucleus. Partial melting processes in the continued evolution of the mantle, crust, hydrosphere and atmosphere. Most of the primordial carbon remained in the Earth's mantle.

   Tectonic processes of high-magnitude enable rise of volatiles from the mantle to shallower crustal levels on Earth. Reactivation of the megastructures in sedimentary basins over its geological history may also promote the upwelling and migration of hydrocarbons.

 

Cosmic abundance of the elements

According to studies performed by Massachusetts Institute of Technology (MIT) to estimate the distribution of carbon on Earth is:

Biosphere, oceans, atmosphere ....... 3.7 x 10e+18 moles

Crust

Organic carbon .............................. 1100 x 10e+18 moles

Carbonates .................................... 5200 x 10e+18 moles

Mantle ....................................... 100000 x 10e+18 moles

Earth's Carbon Budget (MIT)

   Earth's mantle contains according that estimating about 20 times more carbon than in the superficial layers of the planet. This carbon within the mantle is in the oxidized form such as carbon dioxide, carbonates; and not oxidized asdiamonds, hydrocarbons (oil and natural gas) and possibly metal carbides.   There is a serious problem when we use the word "organic carbon" or organic chemistry. Dr. Thomas Gold reminds us that we can read a whole book of organic chemistry without mentioning any organism (biology). A rock thatcontains carbon does not mean that all or part of this carbon is of biological origin, i.e. carbon of real organic biological origin, fossil. This carbon may have migrated in the form as hydrocarbons and inorganic interacted with the rock atlow pressure, including reworking by deep biosphere, by microorganisms that feed on hydrocarbons (archaea) whichalso leave their fingerprints as (biomarkers). Therefore, also the so-called geochemical analyzes of total organic carbon (TOC) in rocks such as shales, actually, do not refer to the organic carbon content of biological origin (as the traditional view would hold), but the analysis of carbon originating from primordial and allocthonous hydrocarbons that migrated from deep sources and are present in these laminates shales. This then leads to a wrong reasoning for suggesting that hydrocarbons would be formed miraculously inside the so-called "source rocks". Therefore unconventional hydrocarbon accumulations in United States such as shale gas (e.g. in Marcellus, Barnett, Bakken, Eagle Ford, Fayetteville, Woodford, Niobrara and all others) and also oil shale as Green River are simply microporous reservoirs and not source-rocks. Other high-order nonsense is to imagine that heat by intrusions of magmas that form igneous rocks such as diabase sills would form hydrocarbons in contact with carbonaceous shales.

   In the process of migration from greater depths hydrocarbons rise to shallower crustal levels carried by helium (He) and Nitrogen (N₂), through cracks in the basement, where subtle decompression occurs. They can stay in porous rocks, fractures and accumulation occurs also trapped in rocks as laminated shales with high microporosity, since the initial migration stages are mostly gas and high pressure systems aided by presence of helium can fix hydrocarbons within these shales.

    It should be noted that the material of biological origin the Earth's surface has a low rate of preservation, initially due decomposition by microorganisms and mainly by oxidation processes. Also in biological detritus dominate biological molecules and other carbohydrate oxidized and no properly hydrocarbon compounds, such as molecules that are dominated in oil and natural gas. Hydrocarbons present in shales are very rich in hydrogen and incompatible with intrinsic biological derivation.

Source: 

http://origeminorganicadopetroleo.blogspot.com.uy/2011/02/normal-0-21-false-false-false-pt-br-x.html

Where does Earth carbon come from?

D,Anton

The importance of the element carbon in planetary and geological processes has been sometimes underestimated. In the Solar System carbon is found in unoxidized form in rhe outer giant planets such as Jupiter, Saturn, Uranus and Neptune. In those planets it appears as methane, ethane and other hydrocarbons. In Venus and Mars carbon is oxidized into CO² representing above 95% of the atmospheric masses. In the Earth, carbon is found in unoxidized forms (coal, crude oil, natural gas, etc) and in oxidized forms as CO² in the atmosphere (400 ppm) and as carbonates in limestones and other calcaire geological formations.

The question thar arises is the following: Where does the carbon on earth come from? The answers are several but two possibilities are prevalent. It may be an original compound from the moments in which the planet.was formed or resulted from the ascent of methane (and other hydrocarbons) through the crust. The first theory relates to the biogenic theory of petroleum formation and the second to the abiotic hypothesis. Thomas Gold was a energetic supporter of the second theory. Here we reproduce his views on the carbon cycle on earth.

Clues about Earth carbon in the carbonate record

T.Gold

"The surface and subsurface sediments on the earth contan approximately one hundred timesas much of the element carbon as would have derived from the grinding up of the basementrocksthat contributed to the sediments. This surface is thus enormoously enriched in carbon. This enrichment requires an explanatiion.

The total quantity of carbon contained in the sediments and on the surface isestimated to average about 200 tons per each square meter of the earth surface area.

One-fifth of all this carbon is in unoxidized form, including various forms of coal, crude ols, kerogen (carbonaceous compounds diffusely distributed in the rocks), and natural gas, either as free gas or in the form of methane hydrate ices. In addition, there is the thin veneer of living and not-yet-decomposed biological material. This latter category- in my opinion the only demonstrably biological component-represents only a very small fraction of the total unoxidized carbon.

The other four-fifthof the carbon is the oxidized form, mostly limestone (calcium carbonate), and dolomite (a blend of calcium and magnesium carbonate). Much of this carbonate was deposited in oceansm, having derived the carbon from the atmospheeric-oceanic pool of carbon dioxide. Carbonate precippitates naturally out of the water column from dissolved carbon dioxide and calcium and magnesium oxides. It can also be precipitated out of the water biologically, by organisms that build carbonate shells or skeletons."

Reproduced from "The Deep Hot Biosphere", Thomas Gold,  2001.
More information in "Inexhaustible? Petroleum and Natural Gas",  D.Anton, Piriguazu Ediciones