摘要
中上奥陶统萨尔干页岩与印干页岩是塔里木盆地重要的海相烃源岩。通过对柯坪地区大湾沟剖面中上奥陶统萨尔干页岩、印干页岩与其上下地层关系的探地雷达测量,形成反映岩—震关系的地球物理剖面,从而将露头中的页岩准确标定于地震剖面中。以此标定成果为据,追踪阿瓦提凹陷内75条二维地震测线(总长1.8×104km)中的烃源岩,准确地刻画出了萨尔干页岩、印干页岩的展布范围。萨尔干页岩、印干页岩在阿瓦提凹陷内大面积展布,其西北部受控于沙井子断裂,北部超覆尖灭于胜利1井以南,东部超覆尖灭于满西2井附近台地边缘(此为新发现台缘),南部则止于巴楚断隆,西南部受控于阿恰断裂带。由于萨尔干页岩是中晚奥陶世形成的盆地初期沉积的烃源岩,其分布范围与厚度均小于印干页岩,但其有机质丰度却高于印干页岩。萨尔干页岩与印干页岩沉积时属于深水陆棚—盆地相环境,沉积古水深大致在60~200,m,甚至更深些。
The Middle-Upper Ordovician Salgan and Yingan shales are important marine hydrocarbon source rocks in the Tarim Basin. Ground Penetrating Radar(GPR)was used in measuring the relationship between black shales and its overlying and underlying strata at the Dawangou outcrop in Keping area in the Tarim Basin. The marker section of GPR was established which reflected the relationship between lithology and and seismic characters. As a result, the distribution of the black shales in the marker section can be correctly interpreted on the seismic profiles. Based on this, the hydrocarbon source rocks of totally 75 two-dimensional seismic lines(up to 18 000 km)in the Awati Sag were traced. The distribution area of the Salgan and Yingan shales was determined which were widely distributed in the study area. They are controlled by the Shajingzi rift in the northwestern region, onlapped in Well Shengli 1 in the southern region and controlled by the Aqia rift belt in the southwestern region. The distribution area and thickness of the Salgan shale are smaller than those of the Yingan shale,while its organic abundance is higher because it was the early deposited hydrocarbon souce rocks of the basin during the Middle-Late Ordovician. The Salgan and Yingan shales were deposited in the deep marine shelf-basin environments with a 60~200,m or even deeper water depth.
出处
《古地理学报》
CAS
CSCD
北大核心
2010年第5期599-608,共10页
Journal of Palaeogeography:Chinese Edition
关键词
中上奥陶统
萨尔干页岩
印干页岩
阿瓦提凹陷
深水陆棚
盆地相
探地雷达
Middle-Upper Ordovician
Salgan shale
Yingan shale
Awati Sag
deep water shelf
basin facies
Ground Penetrating Radar