摘要
华北地区广泛发育着厚达6000—14000m的中上元古界、下古生界海相碳酸盐岩地层，地表各类油苗达42处之多。早在50年代我国石油工作者就对这些油苗作过详细的地质调查。70年代冀中地区发现古潜山型新生古储的油藏后，对华北地区能否找到古生古储油藏的问题，立即引起了我国广大石油科学工作者的共同关注。那么华北地区这套年代古老(10-14亿年)的海相碳酸盐岩有机质丰度如何?目前处于演化的那一阶段?华北地区能否在碳酸盐岩中找到油藏，这是本文将要论述的重点。
The Middle-Upper Proterozoic and Lower Paleozoic carbonate formations in nor-thern China are well developed, with an accumulative thickness of 6000-14000 m. Both seepages and oils have been found in the outcrops and drilling wells.The maturity of organic matter in these caribonate formations is obviously lower than that in southern China, as viewed from reflectivity (R°), H/C (atom), the amo-unt and distribution of hydrocarbons, Tmax℃and so on. The Tmax℃ may be used as a principal index for determining the maturity of organic matter in carbonate rock-covered areas. According to the results of the measurement of Tmax℃ and E° for natural sam-ples and simulating experiments on bitumens from caribonate. rocks, the limitation va-lues for oil and gas have been estimated at 455℃ (R°=1.35) and 476℃ (E°=2.25), re-spectively. On this basis, the maps of organic matter maturity for the Middle-Upper Proterozoic, Ordovician, Cambrian and Carboniferous of northern China have been com-piled. It has been proposed that prospects of both oil and gas are expected, with oil and condensate dominant in the Ordovician, and condensate and dry gas in the Middle-Up-per Proterozoic. The Cambrian is intermediate between them.
出处
《地球化学》
CAS
1985年第2期150-162,共13页
Geochimica
