THE FORMATION MECHANISM OF THE HEFEI BASIN AND ITS OIL AND GAS EXPLORATION PROSPECT
JIA Hong-yi ；LIU Guo-hong；ZHANG Yun-yin；ZHANC Ri-hua (Geophysical Exploration Institute of Shengli Oil Field Dongying 257100, China)
The Hefei Basin is a synorogenic foreland basin with the Dabie orogen. The eastern part of the basin was considerably in- fluenced by the Tanlu Fault during its development. The basement of the basin is the southern edge of the North china Plate, which lithologically consists of the Palaeozoic. As a Mesozoic and Cenozoic terrestrial facies sedimentary basin its cover is well developed with a thickness of 12000m. The basin is divided into four first - class tectonic units, forming a framework of "three deperssions sur- rounding one rise". Four transbasinal major faults are EW - trending and south - dipping transform faults which are shown as the re- verse followed by the normal. There are five suites of hydrocarbon source rocks such as the C - P, J_1-2, K_1-2 and E in the basin. The central uplift is the major indicator of oil and gas. So it is an oil and gas- bearing basin with great potential in exploration.