Acta Petrolei Sinica ›› 2017, Vol. 38 ›› Issue (6): 666-676.DOI: 10.7623/syxb201706006

• Petroleum Exploration • Previous Articles     Next Articles

A new pore pressure logging prediction method in shale gas reservoirs

Xu Chunlu1, Sun Jianmeng1, Dong Xu1, Lai Fuqiang2   

  1. 1. School of Geosciences, China University of Petroleum, Shandong Qingdao 266580, China;
    2. Chongqing Key Laboratory of Complicated Oil & Gas Field Exploration and Development, Chongqing University of Science and Technology, Chongqing 401331, China
  • Received:2016-09-08 Revised:2016-12-14 Online:2017-06-25 Published:2017-07-08

页岩气储层孔隙压力测井预测新方法

徐春露1, 孙建孟1, 董旭1, 赖富强2   

  1. 1. 中国石油大学地球科学与技术学院 山东青岛 266580;
    2. 重庆科技学院复杂油气田勘探开发重庆市重点实验室 重庆 401331
  • 通讯作者: 徐春露,女,1992年1月生,2014年获中国石油大学(华东)学士学位,现为中国石油大学(华东)地质资源与地质工程专业硕士研究生,主要从事测井数据处理与解释以及地应力预测工作。Email:xuchunlu0129@126.com
  • 作者简介:徐春露,女,1992年1月生,2014年获中国石油大学(华东)学士学位,现为中国石油大学(华东)地质资源与地质工程专业硕士研究生,主要从事测井数据处理与解释以及地应力预测工作。Email:xuchunlu0129@126.com
  • 基金资助:

    国家自然科学基金青年科学基金项目(No.41402118)和国家重大科技专项(2016ZX05006-002-004)资助。

Abstract:

Obvious abnormal high-pressure phenomena often occur in shale gas reservoir; the pore pressure can increase greatly in a short distance. If the abnormal high-pressure values cannot be predicted timely and accurately, well kick, blowout and other drilling accidents will be caused, not only bringing great losses to drilling construction, but also seriously affecting the reservoir evaluation. However, the existing method is very difficult to predict the abnormal pore pressure value in shale gas reservoir. In combination with the experimental data of shale gas core, based on full consideration of the influences from porosity, organic matter content and effective stress on acoustic velocity, a new pore pressure prediction method for shale gas reservoir is proposed on a basis of acoustic velocity model. In this method, the relationship of P-wave and S-wave velocity in the gas-free horizons is used for gas-bearing correction at the P-wave velocity of reservoir, so as to eliminate the influences of gas on abnormal high pressure phenomenon in terms of acoustic logging information characterization. In addition, this method is able to predict the abnormal pore pressure of shale gas reservoir induced by multiple mechanisms such as unbalanced compaction and hydrocarbon generation function, thus overcoming the deficiency in the traditional method only able to predict the abnormal high pressure caused by unbalanced compaction. Well S in shale reservoir of Zhaotong area is taken as an example for reservoir pore pressure prediction, thus obtaining the technical flow of the reservoir pore pressure prediction method based on acoustic velocity model.

Key words: shale gas reservoir, pore pressure prediction, organic matter, gas-bearing correction, acoustic velocity

摘要:

页岩气储层中常出现明显的异常高压现象,其孔隙压力会在短距离内大幅上升。若不能及时准确预测这些异常高压值,可能导致井涌、井喷等钻井事故,不仅会给钻井施工造成重大损失,还严重影响储层评价工作。然而,现有的方法却很难准确预测页岩气储层中的异常孔隙压力值。结合页岩气岩心实验数据,在充分考虑孔隙度、有机质含量和有效应力对声波速度影响的基础上,提出了一套基于声波速度模型的页岩气储层孔隙压力预测新方法。该方法通过使用不含气层段的纵波、横波速度关系对储层纵波速度进行含气性校正,消除了气体对异常高压现象在声波测井信息表征上的影响。此外,该方法还能预测因不平衡压实和生烃作用等多种机理引发的页岩气储层异常孔隙压力,弥补了现有传统方法只能预测由不平衡压实引起异常高压的不足。以昭通地区页岩地层S井为例进行储层孔隙压力预测,形成了基于声波速度模型的储层孔隙压力预测方法技术流程。

关键词: 页岩气储层, 孔隙压力预测, 有机质, 含气性校正, 声波速度

CLC Number: