泥页岩有机质对超压成因判识的影响及校正方法

The Influence of Organic Matter on the Origin Identification of Overpressure in Shale and Correction Method

摘要: 由于有机质的存在，使得用测井资料方法识别超压成因结果会产生一定程度的偏差。本文着重介绍了泥页岩有机质对超压成因识别的影响，即泥页岩中有机质含量会严重影响孔隙度测井系列的准确性，从而降低超压成因识别方法的可靠性。于是，本文系统地提出校正有机质的超压识别方法，即利用已知实验分析数据、测井参数数据、地球化学技术等，通过各种方法预测研究区的有机质含量(一般用总有机碳含量代表)，然后利用岩石体积物理模型对孔隙度测井进行有机质校正，最后利用超压成因识别方法判别超压成因。通过对比有机质校正前后得到的超压成因判识结果，发现校正前的超压成因结果与校正后的超压成因结果存在较大的差异，而校正后的超压成因判识结果更符合研究区地质背景，能更好地指导油气勘探开发工作。

Abstract: Due to the existence of organic matter, there is some deviation in identifying the cause of over-pressure by logging technology. This paper mainly focuses on the influence of organic matter in mud shale on identification of overpressure origin, because the content of organic matter in mud shale will seriously affect the accuracy of porosity logging series, which reduces the credibility of identification method of overpressure origin. Then, this paper systematically puts forward overpressure identification methods for correcting organic matter, including using the known experimental analysis data, well logging parameter data, geochemical techniques, etc. Through various methods to predict organic matter content (generally represented by total organic carbon content or TOC) in the chosen area, the volume of rock physical model is then used to correct organic matter porosity logging parameters. Finally, the overpressure cause identification method is used to identify the overpressure cause after corrected. By comparing the analysis result of overpressure before and after the organic matter correction, it is found that there is more or less difference between the overpressure origin before correction and one after correction. It is suggested by a host of studies that the corrected overpressure cause results are more in line with the conditions of the study area, which can better guide oil and gas production.