渤南青东凹陷烃源岩有机碳含量测井预测模型

Logging prediction model of organic carbon content in source rock in the Qingdong Sag,Bonan Basin,China

以渤海南部海域典型的边缘凹陷——青东凹陷为例,研究边缘凹陷烃源岩有机碳含量测井预测模型。基于烃源岩样品有机碳含量与测井属性之间特殊的响应关系,采用多元回归方法,建立了烃源岩有机碳含量的测井预测模型,获得了有机碳含量在纵向上的连续变化值。研究结果显示,青东凹陷沙三中下亚段与沙四上亚段有机碳含量相对较高,烃源岩品质好(有机碳质量分数>0.5%),有效烃源岩厚度大,能够为油气规模成藏提供有利的烃源岩条件。边缘凹陷也可发育优质烃源岩。

Taking Qingdong Sag,a typical marginal sag in the southern Bohai Sea,as an example,the logging prediction model of organic carbon content in source rocks in the marginal sag is studied.Based on the special response relationship between the organic carbon content of hydrocarbon source rock samples and logging properties,a logging prediction model for the organic carbon content of hydrocarbon source rock samples is established by using multiple regression method,and the continuous longitudinal variation of the organic carbon content is obtained.The results show that the Es3M-L and Es4U in Qingdong Sag have relatively high organic carbon content,good source rock quality(organic carbon mass fraction>0.5%),and large effective source rock thickness,which can provide favorable source rock conditions for oil and gas accumulation.High quality source rocks are also developed in marginal sag.The well logging prediction model of Paleogene source rocks in Qingdong Sag provides important information and reference for the prediction of source rocks in other marginal depressions in the Bohai Sea area.