Genesis and energy significance of natural hydrogen

H-2 is clean energy and an important component of natural gas. Moreover, it plays an irreplaceable role in improving the hydrocarbon generation rate of organic matter and activating ancient source rocks to generate hydrocarbon in Fischer-Tropsch (FT) synthesis and catalytic hydrogenation. Compared with hydrocarbon reservoir system, a complete hydrogen (H-2) accumulation system consists of H-2 source, reservoirs and seal. In nature, the four main sources of H-2 are hydrolysis, organic matter degradation, the decomposition of substances such as methane and ammonia, and deep mantle degassing. Because the complex tectonic activities, the H-2 produced in a geological environment is generally a mixture of various sources. Compared with the genetic mechanisms of H-2, the migration and preservation of H-2, especially the H-2 trapping, are rarely studied. A necessary condition for large-scale H-2 accumulation is that the speed of H-2 charge is much faster than diffusion loss. Dense cap rock and continuous H-2 supply are favorable for H-2 accumulation. Moreover, H2O in the cap rock pores may provide favorable conditions for short-term H-2 accumulation.