辽东湾地区主力烃源岩分布特征与主控因素

利用辽东湾地区岩心、地化及测井资料，全面评价和预测了烃源岩分布和特征，解决了烃源岩评价标准不一、发育主控因素不明确的问题.其中，东三段、沙一段和沙三段烃源岩均为该区主力烃源岩，综合利用岩心及地化资料，明确了烃源岩有机地球化学特征，结合测井信息建立了各套烃源岩有机碳含量和热解烃的测井预测模型，并预测了烃源岩的有机质丰度和类型平面分布特征；基于区域构造和沉积背景分析，归纳了辽东湾地区烃源岩发育的主控因素.结果表明，烃源岩在平面及纵向分布上均有差异，且构造沉降速率、古生产力大小和盐度值与烃源岩有机碳含量具有明显相关性.辽西和辽中凹陷共发育5个生烃中心，辽中凹陷烃源岩整体优于辽西凹陷，且由东北至西南方向，烃源岩品质逐渐变差；纵向上沙一段最优，沙三段次之，东三段最差；构造沉降速率较快、古生产力较高及沉积水体盐度高导致的缺氧环境是辽东湾地区烃源岩发育的主控因素. 

Distribution Characteristics and Main Controlling Factors of Main Hydrocarbon Source Rocks in Liaodong Bay Area

This study focuses on the distribution and characteristics of hydrocarbon source rocks in Liaodong Bay area, and the related issues involving inconsistent evaluation standards and unclear development controlling factors, by using core, geochemistry and logging data. Firstly, the organic geochemical characteristics of main hydrocarbon source rocks in Dong-3, Sha-1 and Sha-3, are studied by the core and geochemistry data. Then the logging prediction model of organic carbon content and pyrolysed hydrocarbon is established with logging data to predict the plane distribution characteristics of hydrocarbon source rocks. Lastly, the main controlling factors of hydrocarbon source rocks are generalized on the basis of results of subsidence history, sedimentary background. The results show that the plane and vertical distributions of hydrocarbon source rocks are different; the tectonic subsidence rate, paleoproductivity, and salinity have correlation with organic carbon content. There are 5 hydrocarbon generation centers in Liaoxi and Liaozhong sags in the plane scale, and the quality of hydrocarbon source rocks in Liaozhong sag is better than that of Liaoxi sag, which gets increasingly worse from northeast to southwest. In vertical section, the hydrocarbon source rocks in Sha-1 is the best, good in Sha-3, but poor in Dong-3. It is found that the fast tectonic subsidence rate, high paleoproductivity and anaerobic environment caused by high salinity are the favorable factors for hydrocarbon source rock development in Liaodong Bay area.