胜坨地区页岩油储层脆性井震联合预测

Integrated Well-Log and Seismic Prediction Method for Brittle Reservoirs of Shengtuo Area Shale Oil

摘要: 脆性指数(BI)是评价页岩油气储层的重要指标之一，在页岩油气勘探开发中对有利目标区评价、井位设计等有重要指导价值。与北美海相页岩油气储层相比，胜坨地区受多期次构造运动影响，构造非常复杂，储层非均质性强，相应的页岩油储层脆性预测评价技术匮乏。为此，研究针对胜坨地区复杂的构造和沉积特点，从ly2-1hf等井沙四纯上段页岩油储层岩芯样品分析入手，通过对地质、测井和地震等资料的综合研究，以及地震正演模拟方法的应用，明确了页岩油储层脆性的主要影响因素及敏感弹性参数，建立了本区页岩油储层6种岩相组合的测井曲线和地震响应特征与脆性指数关系，建立适用于本区的新的脆性指数计算模型，总结了基于敏感参数的叠前直接反演脆性指数的有效预测方法及技术流程，并取得了良好的应用效果。对于类似复杂地区页岩油气高效勘探开发具有重要指导意义。

Abstract: Brittleness index (BI) is one of the important indexes for evaluating shale oil and gas reservoirs, and it has important guiding value for favorable target area evaluation and well location design in shale oil and gas exploration and development. Compared with marine shale oil and gas reservoirs in North America, Shengtuo area is affected by multi-stage tectonic movement, with very complex structure and strong reservoir heterogeneity, and the corresponding shale oil reservoir brittleness prediction and evaluation technology is lacking. Therefore, in view of the complex structural and sedimentary characteristics in Shengtuo area, this study starts with the analysis of shale oil reservoir core samples in the upper member of Shasichun in Well ly2-1hf, and through the comprehensive study of geological, logging and seismic data, as well as the application of seismic forward modeling method, the main influencing factors and sensitive elastic parameters of shale oil reservoir brittleness are defined, and the relationship between logging curves and seismic response characteristics of six lithofacies combinations of shale oil reservoirs in this area and brittleness index is established. A new brittle index calculation model suitable for this area is established, and the effective prediction method and technical process of pre-stack direct inversion brittle index based on sensitive parameters are summarized, and good application results are obtained. It has important guiding significance for efficient exploration and development of shale oil and gas in similar complex areas.