Abstract:

According to conventional oil-forming theories,the oil and gas fields can be only occurred in two types of geotectonic conditions,i.e.geosyncline-type and platform-type basins.Based on the practical experiences and the geological contributions available,the authors have suggested a new geotectonic systematics of oil and gas fields in China,using the diwa(geodepression)theory of oil formation.While dealing only with the diwa-type oil and gasfields which spread most widely in China and have great economic significance,attention is drawn to their basic characteristics and distribution regulari-ties in order to show a guidance to petroleum searching.Both of oil and gas fields formed in an environment of activated and inactivated platforms,as well as in that of geosynclines in China,have already been discussed in other papers.