THE PRESENT SITUATION AND DEVELOPMENT OF OIL AND GAS GEOCHEMICAL EXPLORATION IN CHINA

In recent years,two remarkable changes have taken place in the concept of oil and gas geochemical exploration,i.e.,the oil and gas geochemical exploration has grown from the points(oil and gas reservoirs) to the extensive regions(main oil and gas basins in China),and from the shallow(near-surface) part to the depth(downhole exploration);the oil and gas geochemical exploration has developed from the reconnaissance survey to the four-grade survey stage consisting of general survey,reconnaissance survey,detailed survey and intensive survey.Remarkable advances have been recently made in oil and gas geochemical exploration of China.The method and technology for geochemical exploration have gained development,the basic theoretical researches have made advances,some new test and analysis techniques have been developed,the new data-processing and interpretation-evaluation system has been formulated,and the database of oil and gas geochemical exploration for main oil and gas basins in China has been set up.This paper describes the development trend of oil and gas geochemical exploration in China.