Hydrocarbon accumulations: hypothesis of two main formation ways

Within the framework of the recently developed concept of the global biosphere carbon cycling, the issue of HC accumulation origin on the Earth is considered. A hypothesis is proposed about two main ways of hydrocarbon cluster formation, namely: the biogenic way of liquid hydrocarbon (oil) accumulation and the abiogenic way of gaseous hydrocarbon accumulation. The biogenic pathway is related to Organic Matter formed by photo- and heterotrophic synthesis and subsequent transformation of OM in sediment as the only carbon source for liquid hydrocarbons. After reaching a certain level of maturity, OM releases a mobile part, which emigrates into traps thus forming an oil deposit. The conditions of accumulation of "living" Organic Matter and its characteristics depend on the conditions of photo- and heterotrophic synthesis, which change during orogenic cycles that repeat over time. The dynamics of orogenic cycles, their division into periods of different duration, the beginning and end of the cycles depend on lithosphere plates movement and deep "breathing" of the Earth. The key moment is the orogenic cycles change accompanied by abrupt changes in the living conditions of organisms. Most of them die, providing conditions for the formation of sediments rich in OM ("black shales"). The abiogenic pathway of HC accumulations formation is directly related to deep "breathing" of the Earth associated with of deep fluid dynamics. The most important point is rifting, when the flow of hydrogen and the products of its interaction with carbon, together with the flow of magma, break through the lithosphere shell and enter the earth's crust. Because of its high mobility, hydrogen dissipates, and products of its interaction with carbon (methane and its closest homologues) form a gas deposit. Characteristics of chemical composition of oil and gas hydrocarbon accumulations are associated with their origin. The hypotheses about biogenic and abiogenic ways of hydrocarbon clusters formation correlate with the existing concepts of "organic" and "inorganic" origin of oil