摘要
塔里木盆地库车坳陷白垩系砂岩气藏效益开发面临着超深、高温、高压、高应力等挑战,亟待解决巨厚高抗钻砾石层和复合盐层的钻井安全提速,以及极低的基质孔隙度和渗透率储层的改造提高产量这两大难题。为此,以库车坳陷克拉苏构造带西部的博孜3号构造为例,在系统梳理钻完井工程问题与地质因素之间的关联性基础上,建立了相应的地质和地质力学三维模型,形成了超深井安全提速提产地质工程一体化关键技术。研究结果表明:①钻前为保证储层钻遇、安全提速和完井提高产量来确定井位、井型和井轨道;②以盐岩、砾岩、断层等特殊地质体的描述,地层可钻性评价,异常高压预测、井壁稳定性和漏失压力预测的结果,确定井身结构、钻头与提速工具及钻井液设计;③随钻过程中,根据实钻信息及时修正地质力学模型,实时更新钻井“三压力”数据,支持钻井参数动态调整;④建立了包括储层基质、裂缝、地应力、岩石力学属性等多因素综合的可压裂性预测方法,模拟人工裂缝与天然裂缝交互的压裂网络,优化储层改造方案。通过现场实践,平均钻井复杂率由原来的8%降低至4.6%,气井天然气无阻流量提高3~10倍,所形成的提产提速地质工程一体化关键技术为超深层油气资源的开发积累了技术方法和实践经验。
Benefit development of Cretaceous sandstone natural gas reservoirs in Kuqa Depression of the Tarim Basin faces the challenges of ultra depth,high temperature,high pressure and high stress,and now it is in urgent need to solve two difficult problems,i.e.,the safe improvement of rate of penetration(ROP)in thick poor-drill ability gravel beds and compound salt formations and the production stimulation of reservoirs with extremely low matrix porosity and permeability.Taking Bozi 3 structure in the western Kelasu structure zone of Kuqa Depression as an example,this paper systematically analyzes the relationships between drilling and completion engineering problems and geological factors,establishes a corresponding 3D geological and geomechanical model and develops key technologies of geology-engineering integration for safe ROP improvement and production increase of ultra-deep wells.And the following research results are obtained.First,before drilling,well location,well type and well trajectory are optimized in consideration of reservoir drilling,safe ROP improvement and completion production increase.Second,casing program,bit and ROP improvement tools and drilling fluid design are optimized based on the description of salt rocks,conglomerates,faults and other special geological bodies,combined with the results of formation drill ability evaluation,abnormal pressure prediction,wellbore stability and leakage pressure.Third,in the process of drilling,the geomechanical model is modified timely according to the actual drilling information,and the drilling"three pressure"data is updated in real time to support the dynamic adjustment of drilling parameters.Fourth,a comprehensive fracturing ability prediction method including reservoir matrix,fracture,in-situ stress,rock mechanical properties and other factors is established and the fracturing network of hydraulic fractures and natural fractures is simulated to optimize the reservoir reconstruction scheme.In conclusion,field practice shows that the average drilling complexity is reduced from 8%to 4.6%,and the absolute open flow of gas well is increased by 3-10 times.It is indicated that the key technologies of geology-engineering integration for production increase and ROP improvement providing technical methods and practical experience for the development of ultra-deep oil and gas resources.
作者
胥志雄
张辉
尹国庆
徐珂
王海应
王志民
刘新宇
董仁
周建平
XU Zhixiong;ZHANG Hui;YIN Guoqing;XU Ke;WANG Haiying;WANG Zhimin;LIU Xinyu;DONG Ren;ZHOU Jianping(PetroChina Tarim Oilfield Company,Korla,Xinjiang 841000,China;Exploration and Development Research Institute,PetroChina Tarim Oilfield Company,Korla,Xinjiang 841000,China;Engineering Technology Department,PetroChina Tarim Oilfield Company,Korla,Xinjiang 841000,China)
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2021年第11期104-114,共11页
Natural Gas Industry
基金
中国石油天然气股份有限公司重大科技专项“库车坳陷深层—超深层天然气田开发关键技术研究与应用”(编号:2018E-1803)。
关键词
塔里木盆地
库车坳陷
超深气井
地质力学
地质工程一体化
提速
提高产量
Tarim Basin
Kuqa Depression
Ultra-deep gas well
Geomechanics
Geology-engineering integration
ROP improvement
Production increase
