摘要
松辽盆地北部T2反射层断裂与中浅层油气的运聚成藏关系紧密,揭示T2反射层断裂密集带的成因机制对指导油气勘探至关重要.基于松辽盆地北部区域地震解释,从分析断裂发育特征着手,以断裂形成演化过程为主线,系统剖析了盆地演化不同阶段断裂的变形机制,揭示了T2反射层断裂密集带的形成机制及其对油气运聚成藏的指示作用.研究表明,T2反射层断裂密集带是在断陷演化基础上,在断陷期断裂先存构造、泉一二段塑性泥岩盖层水平拆离作用和近EW向拉张应力场的控制下形成的,全区以近SN向拉张机制伸展型密集带为主,NE向、NW向和近EW向斜拉机制调节型密集带和走滑调节型密集带零星分布.盆地反转期受断陷半地堑、基底深大断裂和左旋压扭变形场控制形成反转构造带的同时,反转构造带内的断裂密集带被逆时针旋转改造而定型,呈NW-NNW向展布为主.反转构造带内T2反射层NW-NNW向断裂密集带边部断裂和未反转区带内T2反射层近SN向断裂密集带边部断裂长期活动,与油气大量生排烃时期匹配,是中浅层油气运聚成藏的油源断层.
The relationship between T2 reflector fault and hydrocarbon accumulation reservoir of middle-shallow layer is close, which proves genetic mechanism of T2 reflector fault dense zones is important for hydrocarbon exploration. Based on the north- ern Songliao basin regional seismic interpretation, the analysis of the development characteristics and the formation and evolu- tion of fault, we systematically analyze fault deformation mechanism at different stages, which reveal formation mechanism of T2 reflector fault dense zones and indication of hydrocarbon exploration. This study shows that T2 reflector fault dense zones have been formed through the following three preriods, namely, the initial faulted period, pre-structure in faulted period, and level detachment of plastic mudstone cap rock and EW tension stress field in Quanyi member. Stretch dense zones of SN ten- sion stress mechanism dominates the region. Accommodation and strike slip accommodation dense zones of NE, NW and EW oblique stretch mechanism is fragmentary in distribution. Sinistral compresso-shear deformation field, half grabens during faul- ted period and basal huge faults jointly control the formation of subprime anticlines and structural inversion belts during re- versed period, meanwhile, fault dense zones of structural inversion belts reform and setting as main NW-NNW by counter- clockwise rotation. Edge fault in T2 reflector NW-NNW fault dense zones of structural inversion belts and SN fault dense zones of structural non-inversion belts are long-term activity, of which time. They are oil-migrating faults of hydrocarbon accumulation matches with hydrocarbon generation and expulsion phase in reservoir in middle-shallow layer.
出处
《地球科学（中国地质大学学报）》
EI
CAS
CSCD
北大核心
2013年第4期797-806,共10页
Earth Science-Journal of China University of Geosciences
基金
国家自然科学基金项目(No.41072163)
高等学校博士学科点专项科研基金(No.20112322120002)
关键词
T2反射层断裂密集带
成因机制
先存构造
反转构造带
松辽盆地北部
石油地质
T2 reflector fault dense zone
genetic mechanism
pre-structure
structural inversion belts
northern Songliao ba-sin petroleum geology.
