Acta Petrolei Sinica ›› 2020, Vol. 41 ›› Issue (2): 244-252.DOI: 10.7623/syxb202002010

• Oil Field Development • Previous Articles     Next Articles

Dynamic mechanism and dynamic evolution process of abrupt bottom-hole rock burst in Well QL1

Luo Chengbo1,2, Jiang Zujun1, Li Gao2, He Long3, Meng Yingfeng2, Ou Biao1, Xiao Guoyi1, Yan Yancheng1, Wang Xiyong1   

  1. 1. Petroleum Engineering Technology Research Institute, Sinopec Southwest Oil & Gas Company, Sichuan Deyang 618000, China;
    2. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Sichuan Chengdu 610500, China;
    3. Sinopec Southwest Oil & Gas Company, Sichuan Chengdu 610059, China
  • Received:2018-10-10 Revised:2019-11-26 Online:2020-02-25 Published:2020-03-09

QL1井井底突发性岩爆动力学机理及动态演化过程

罗成波1,2, 蒋祖军1, 李皋2, 何龙3, 孟英峰2, 欧彪1, 肖国益1, 严焱诚1, 王希勇1   

  1. 1. 中国石油化工股份有限公司西南油气分公司石油工程技术研究院 四川德阳 618000;
    2. 西南石油大学油气藏地质及开发工程国家重点实验室 四川成都 610500;
    3. 中国石油化工股份有限公司西南油气分公司 四川成都 610059
  • 通讯作者: 罗成波,男,1985年9月生,2009年获西南石油大学学士学位,2019年获西南石油大学博士学位,现为中国石油化工股份有限公司西南油气分公司在站博士后,主要从事欠平衡钻井岩石力学方面的研究工作。Email:457105796@qq.com
  • 作者简介:罗成波,男,1985年9月生,2009年获西南石油大学学士学位,2019年获西南石油大学博士学位,现为中国石油化工股份有限公司西南油气分公司在站博士后,主要从事欠平衡钻井岩石力学方面的研究工作。Email:457105796@qq.com
  • 基金资助:

    国家科技重大专项"低渗油气藏钻井液完井液及储层保护技术"(2016ZX05021-004)资助。

Abstract:

Bottom-hole rock burst occurred in high-pressure fracture traps consisting of tight sandstones drilled in nitrogen drilling, basically resulting in the malignant blowout accident in Well QL1. The dynamic mechanism of bottom-hole rock burst was analyzed using the theoretical method for the study of wellbore instability, and the dynamic evolution simulation of rock burst was performed by means of Visual Basic and Matlab programming. The research suggests when the bottom hole is gradually approaching the high-pressure fracture trap, the difference between circumferential stress and radial stress of the crack face gradually increases, and the increasing shear stress caused by the difference between principal stresses leads to the compression-shear failure and the composite failure resulted from compression, shear and tension. Until the wellbore is communicated with the failure zone and the high pressure gas carrying plenty of debris is injected into the well, a large amount of energy is released to trigger bottom-hole rock burst. The research results systematically explain the abnormal changes of logging monitoring parameters in the well QL1. The results not only provide a theoretical basis for the prevention and control of rock burst, but also provide a new perspective for studying the dynamic instability of deep rock in the field of petroleum engineering.

Key words: gas drilling, effective stress, high-pressure fracture trap, bottom-hole stress, bottom-hole rock burst

摘要:

氮气钻井钻遇致密砂岩高压裂缝圈闭导致井底岩爆是四川盆地西部白马庙构造QL1井恶性井喷事故的根本诱因。利用研究井壁失稳的理论方法来进行井底岩爆的动力学机理分析,并借助Visual Basic语言和Matlab软件编程,进行了岩爆的动态演化模拟。研究认为,当井底逐渐接近高压裂缝圈闭的过程中,裂缝面周向应力和径向应力差值逐渐增大,主应力之间的差值所引起的剪应力增长使裂缝面产生压剪破坏及压剪-拉伸复合破坏,直至破坏区连通井筒,高压气体携带大量碎屑喷入井内,释放大量能量,产生井底岩爆。该研究成果系统解释了QL1井录井监测参数的异常变化,其研究结果不仅可为岩爆的防治提供理论基础,而且在石油工程领域为深部岩体动力学失稳研究提供了一个新的视角。

关键词: 气体钻井, 有效应力, 高压裂缝圈闭, 井底应力, 井底岩爆

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