Recent advances and developing trend of hydrocarbon geochemical exploration in China

The concept of the hydrocarbon geochemical exploration technique has been significantly changed and the great advances of this technique have been taken place in recent years in China. A theory of pressure-driven gas-phase permeation along fractures has been proposed based on the research results of the genetic mechanism and the pattern of the oil and gas geochemical anomaly, as well as the simulation experiment results of the vertical hydrocarbon microseepages. Based on some traditional oil and gas geochemical exploration methods such as acid-extraction hydrocarbon, alteration carbonate, fluorescence spectrum and ultra-violet spectrum, some new methods (indicators) have been established including heat-released hydrocarbons, aromatic hydrocarbons from high-performance liquid chromatography, physically-adsorbed hydrocarbon gas, and obligate hydrocarbon-oxidizing bacteria. New application areas of the hydrocarbon geochemical exploration technique have been developed in the non-conventional oil and gas resources such as gas-hydrate and non-organic gas; under the complex geo-morphological conditions such as the desert, the gobi area, the loess covered area, and the mountain area, etc.; and especially in the offshore environment such as the South China Sea, the East China Sea, the Yellow Sea, the Bohai Sea and the Taiwan Strait. A hydrocarbon geochemical exploration database of the main petroliferous basins in China has been established, and some newly developed data-processing and interpretation and evaluation methods have been applied such as the decision -making analysis, the fractal geometry, and the artificial neural network systems. In summing up experiences, the authors put forward some ideas about the developing trend of the hydrocarbon geochemical exploration technique.