海拉尔盆地石油地质特征及勘探前景

CHARACTERISTICS OF PETROLEUM GEOLOGY AND PETROLEUM POTENTIAL OF HAILAR BASIN

龙永文 张吉光

Long Yongwen Zhang Jiguang

海拉尔盆地是在古生代褶皱基底上形成的中新生代断陷盆地,国内面积为40550km。盆内上侏罗统厚达5300m,其扎赉诺尔群的深浅湖相、沼泽相沉积最厚达4400m,是盆地主要生油层,有机质丰度中等,干酪根属Ⅱ、Ⅲ类,已成熟。盆内呈北东向长条状凹凸相间的构造格局,各凹陷都具有多物源的沉积特征,砂体发育,各类圈闭众多。地面及钻孔中已见多处油气显示,并在海参4井中发现了工业油流,说明盆地勘探前景良好。

Hailar Basin,located on the west side of Da Hinggan Ling,is a fault depression laid upon the folded basement of Hercynian movement with a area of 70480km.Fluviatile and lacustrine deposits of the Jurassic Jalai Nut Group(Jzl)are up to 5300m thick with 7 sags in which their formation thicknesses are thicker than 3000m.The 1000-2000m thick Damoguaihe Formation of the Jalai Nut Group(Jd)is considered to be the maim source bed in which 400-600m thick source rocks are found.Their organic carbon is 2.148%,chloroform bitumen A 791ppm,and total hydrocarbon 379ppm.Based on hydrocarbon productivity,vitrinite reflectance and the n-alkane distribution,the oil generation threshold here is 1500m,and the peak is 3500m.Now commercial oil flow is obtained from sandstone reservoirs.5 kinds of traps,i.e. structural,stratigraphic,lithologic,buried-hill and volcanic traps could be found,and petroleum prospects is brilliant.

10.11743/ogg19860107