摘要
为明确库车坳陷超深致密砂岩储层有效裂缝分布特征,基于古应力产生裂缝、现今应力影响裂缝有效性的原理,根据岩心资料和成像测井数据查明裂缝力学性质并拾取裂缝参数,通过构造恢复反演等效古应力、有限元方法预测现今应力场,并结合DFN离散裂缝网格建模,对库车坳陷克拉苏构造带博孜X区块超深致密砂岩储层裂缝进行预测.结果表明,博孜X气藏构造裂缝以未充填‒半充填的高角度剪切缝为主,局部发育小规模的张性裂缝,大多数裂缝形成于喜马拉雅晚期的快速强烈挤压作用;博孜地区地应力场从白垩纪到新近纪,随着北部力源传导的持续往南推进,应力高值呈现由北向南迁移的特点;博孜X气藏构造裂缝发育分布的非均质性极强,在北东部位的X104井区发育程度高,在南西部位的X103井区周围密度低,现今地应力对裂缝有效性影响显著,进而影响气井产能.博孜X区块裂缝形成受断层和褶皱共同控制,单从构造特征难以准确预测裂缝分布,而通过地质力学原理和方法预测裂缝具有较好的吻合度.在超深层储层,不能只通过孔隙度、储层厚度等因素来评价并预测气井产能的高低.
To clarify the characteristics of fracture distribution in ultra-deep and tight sandstone reservoir in Kuqa Depression,based on the principle of fracture generated by paleo-stress and fracture effectiveness affected by current in-situ stress,determine fracture mechanical properties and pick fracture parameters according to core data and FMI logging data,the present-day in-situ stress field is predicted by structural recovery inversion of equivalent paleo-stress and finite element method,and combined with DFN discrete fracture grid modeling,the fractures of ultra-deep and tight sandstone reservoir in Bozi-X Block of Kelasu structural belt in Kuqa Depression are predicted.The results show that the tectonic fractures of Bozi-X gas reservoir are mainly unfilled semi-filled high angle shear fractures,and small-scale tensile fractures are developed locally.The majority of natural fractures in the study area were formed by rapid and strong compression in the Late Himalayas.From the Cretaceous to Neogene,high stress values moved southwards in Bozi-X area due to the continuous southward advancement of force source.The heterogeneity of tectonic fracture development and distribution in Bozi-X gas reservoir is extremely obvious.The development degree is high in Well X104 area in the northeast and low around Well X103 area in the southwest.Current in-situ stress has a significant impact on fracture effectiveness,and then affects the productivity of gas wells.The formation of fractures in Bozi-X block is jointly controlled by faults and folds.It is difficult to accurately predict the distribution of fractures only from the structural characteristics,but the prediction of fractures by geomechanical principles and methods has a good coincidence.Gas production cannot be evaluated and predicted only by porosity and reservoir thickness.
作者
徐珂
张辉
鞠玮
尹国庆
王海应
王志民
王朝辉
李超
袁芳
赵崴
Xu Ke;Zhang Hui;Ju Wei;Yin Guoqing;Wang Haiying;Wang Zhimin;Wang Zhaohui;Li Chao;Yuan Fang;Zhao Wei(Research Institute of Exploration and Development,Tarim Oilfield Company,PetroChina,Korla 841000,China;School of Resources and Geosciences,China University of Mining and Technology,Xuzhou 221116,China)
出处
《地球科学》
EI
CAS
CSCD
北大核心
2023年第7期2489-2505,共17页
Earth Science
基金
国家重大科技专项(No.2016ZX05051)
中国石油天然气股份有限公司重大科技专项(No.2018E-1803)
中国博士后科学基金项目(No.2019M660269).
关键词
超深致密砂岩储层
裂缝预测
裂缝有效性
地质力学
库车坳陷
石油地质学.
ultra-deep tight sandstone reservoir
fracture prediction
fracture effectiveness
geomechanics
Kuqa Depression
petroleum geology
作者简介
徐珂(1991-),男,高级工程师,博士,从事构造地质学与地质力学的科研和生产工作.ORCID:0000-0001-9062-9563.E-mail:xukee0505@163.com。
