摘要
裂缝是碳酸盐岩油藏主要的渗流通道,对油田开发具有重要的影响。为揭示低角度构造缝特征及分布,进而实现有效注水开发,基于薄片、岩心和成像测井等资料,综合运用观察法和实验法分析了滨里海盆地东缘北特鲁瓦油田构造缝的发育期次,并结合构造演化历史探讨了研究区低角度构造缝成因。研究结果表明:北特鲁瓦油田共发育了 3期构造缝,均以北东一南西走向为主。第1期发育于早二叠纪,以低角度构造缝为主,形成时埋深较浅,充填较早,阴极发光特征以不发光为主,古地应力的最大有效主应力为34.4 MPa;第2期发育于晚二叠纪,以斜交构造缝为主,少部分被充填,阴极发光特征以昏暗发光和明亮发光为主,古地应力的最大有效主应力为42.4 MPa;第3期形成于三叠纪,以高角度构造缝为主,几乎未充填,古地应力的最大有效主应力为52. 2 MPao研究区低角度构造缝主要与构造演化有关,早期的高角度构造缝在地层反转后演变为低角度构造缝。通过对低角度构造缝成因的分析,为北特鲁瓦油田下一步裂缝预测及开发方案部署工作提供了指导。
Fracture is the dominant flow channel for carbonate oil reservoir, which is considered as a crucial element for reservoir development. In order to characterize the low-angle structural fracture and identify its distribution and achieve effective waterflooding development, the core observation and laboratory test were used to analyze the structural fracture development stages of the North Tluwa Oilfield in in the eastern margin of the Caspian Basin based on thin-section, core and imaging logging data. The genesis of structural fracture was also discussed by combining with tectonic evolution history. Research indicates that there are three-stage structural fractures with dominant northeast -southwest strike in the North Tluwa Oilfield. The first-stage structural fractures developed in the Early Permian, which mainly consists of low-angle structural fracture. The fracture development is characterized by shallow buried depth, early filling and non-luminous cathodoluminescence, and the maximum effective principal stress of the paleo- stress is 34.4 MPa. The second-stage structural fractures developed in the Late Permian, which mainly consists of oblique-crossing structural fracture. The fracture development is characterized by small part filling and dim and bright cathodoluminescence, and the maximum effective principal stress of the paleo-stress is 42.4 MPa. The third -stage structural fractures developed in the Triassic, which mainly consists of high-angle structural fracture. The fracture development is characterized by no filling, and the maximum effective principal stress of the paleo-stress is 52.2 MPa. The low-angle structural fracture is mainly related to the tectonic evolution in this region. The early high-angle structural fracture evolved into low-angle structural fracture after stratum inversion. The genesis analysis for the low-angle structural fracture could provide certain guidance for the fracture prediction and development program deployment in the North Tluwa Oilfield.
作者
李长海
赵伦
李建新
王淑琴
李伟强
Li Changhai;Zhao Lun;Li Jianxin;Wang Shuqin;Li Weiqiang(PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083 , China)
出处
《特种油气藏》
CAS
CSCD
北大核心
2019年第3期56-61,共6页
Special Oil & Gas Reservoirs
基金
国家科技重大专项“哈萨克斯坦带凝析气顶裂缝孔隙型碳酸盐岩油藏注水注气开发调整技术研究与应用”(2017ZX05030-002)
关键词
北特鲁瓦油田
碳酸盐岩
裂缝期次
低角度构造缝
North Tluwa Oilfield
carbonate rock
fracture stage
low-angle structural fracture
