What is humic kerogen?

Type III: Humic Coal is an organic-rich sedimentary rock that is composed predominantly of this kerogen type. On a mass basis, Type III kerogens generate the lowest oil yield of principal kerogen types. Hydrogen:carbon atomic ratio < 1.

What is bitumen and kerogen?

Kerogen comprises both pyrolyzable carbon as well as inert carbon that has no petroleum-generation potential. Bitumen is defined by the fraction of organics that is nonvolatile at pyrolysis conditions but soluble in organic solvents.

What is difference between kerogen and bitumen?

Kerogen—the organic matter that is solid and insoluble in organic solvents—is a key component of organic-rich mudstones. Kerogen is consumed during thermal maturation, whereas bitumen is an intermediary formed at low maturity from kerogen and consumed at higher maturities in formation of oil and gas.

How is kerogen converted to petroleum and natural gas?

Upon heating, kerogen converts in part to liquid and gaseous hydrocarbons. Petroleum and natural gas form from kerogen. Kerogen may be classified by its origin: lacustrine (e.g., algal), marine (e.g., planktonic), and terrestrial (e.g., pollen and spores).

How is the van Krevelen diagram used to classify kerogen?

The Van Krevelen diagram is one method of classifying kerogen by ‘types’, where kerogens form distinct groups when the ratios of hydrogen to carbon and oxygen to carbon are compared.

What happens to kerogen during thermal maturation process?

During the process of thermal maturation, kerogen breaks down in high-temperature pyrolysis reactions to form lower-molecular-weight products including bitumen, oil, and gas. The extent of thermal maturation controls the nature of the product, with lower thermal maturities yielding mainly bitumen/oil and higher thermal maturities yielding gas.

What are the results of infrared spectroscopy of kerogen?

Complementary and consistent results have been obtained with infrared (IR) spectroscopy, which show that kerogen has higher fraction of aromatic carbon and shorter lengths of aliphatic chains at higher thermal maturities.