井震联合预测珠江口盆地番禺4洼文昌组烃源岩总有机碳

TOC PREDICTION FOR SOURCE ROCKS OF WENCHANG FORMATION WITH A JOINT LOGGING AND SEISMIC METHOD IN THE PANYU 4 SAG IN PEARL RIVER MOUTH BASIN

烃源岩有机碳含量(TOC)是烃源岩评价的关键表征参数。番禺4洼钻遇文昌组烃源岩的钻井有限,实测地化参数难以反映凹陷内烃源岩全貌,文章通过烃源岩TOC地球物理预测技术,综合运用地球化学、测井和地球物理信息,获得了文昌组烃源岩TOC三维数据体。研究结果表明:文昌组主要发育好-极好烃源岩,TOC主体分布在3.0%~5.0%;文昌组底部主要发育差—中等烃源岩,TOC分布普遍<2.0%;中部发育极好烃源岩,TOC主要分布在4.0%~6.0%;表层优质烃源岩集中发育于南洼中心,TOC主要分布在4.0%左右。预测结果与实测资料匹配关系好,有效地弥补钻井少且分布不均的不足,为精细油气资源潜力评价提供一种全新尝试。

The total organic carbon is a key parameter for source rock evaluation.There are few drillings in the Wenchang Formation source rock in the Panyu 4 Sag.The panorama of source rock cannot be fully revealed by the measured geochemical parameters.The TOC of Wenchang Formation source rocks is predicted by an investigation method of geochemistry,logging and geophysics in this paper.The research results show that the Wenchang Formation is dominated by good to excellent source rocks with TOC ranging from 3.0%to 5.0%.However,the source rocks at the base of Wenchang Formation is falling in the groups of poor to fair source rocks,and the TOC is generally less than 2.0%.The middle of Wenchang Formation is mainly characterized by excellent source rock with TOC ranging from 4.0%to 6.0%.The high-quality source rocks at the top of Wenchang Formation are mainly distributed in the south of Panyu 4 Sag,with TOC varying around 4%.The prediction results matchedwell with the measured data,and could be effectively used for oil and gas resource evaluation in the area lacking of drilling.