Most Precambrian chert is abiogenic
, whereas silica-secreting organisms have controlled the accumulation of most cherrty deposits since the Cambrian.
2] generated by abiogenic
thermal decomposition of organic matter at greater depths (< ~500 m).
There is also, however, a controversial theory which one of us (JMS) does not wish to exclude, that the carbon may have been abiogenic
in ultimate origin, (10) with the vanadium provided by vanadium-porphyrin complexes.
that demonstrates there are so many ways to make hydrocarbons in an abiogenic
The serious problems of abiogenic
synthesis of monomers, polymers, and complex functioning systems are discussed with a continuing emphasis on the increasing degree of complexity required as one moves toward systems that might be considered living.
Methane is also released during the abiogenic
process of biomass burning.
The discussion on abiogenic
origins of oil, gas, and coal and the consequences for public policy if the theory is right (Ehrlich thinks it is) alone are worth the price of the book to anyone who teaches earth sciences, environmental sciences, energy issues--or who is trying to decide what kind of car to buy.
Textural signatures in the alteration products of certain rocks suggest that up to 75% of the uppermost crust is microbially altered (Furnes and Staudigel, 1999), whereas such features in other samples suggest that most alteration is probably abiogenic
(Alt and Mata, 2000).