辽河东部凹陷走滑构造及其与火山岩分布的关系  

The Relationship of Strike-slip Belts and Volcanic Rocks Distribution in the Eastern Depression Liaohe Basin

作　　者：李思伟[1] 王璞珺[1] 丁秀春[2] 方炳钟[2] 冯玉辉[1] 孙晓猛[1] 

机构地区：[1]吉林大学地球科学学院,长春130000 [2]中国石油辽河油田公司勘探开发研究院,辽宁盘锦124010

出　　处：《地质论评》2014年第3期591-600,共10页Geological Review

基　　金：国家973项目(编号2009CB219303)的成果

摘　　要：走滑构造可分为压扭和张扭两类,平面上主干走滑断裂都表现为一条贯通性的走滑构造带,剖面上前者表现为正花状构造(向上撒开的逆断层组),后者表现为负花状构造(向上散开的正断层组)。它们的伴生构造在平面上分别表现为与主干走滑断裂共生的雁列褶皱、雁列逆断层(压扭)和雁列正断层(张扭)。在实际剖面中由于构造应力场的变化还常见由正—负花状构造组合的复合花状构造。在平行于走滑构造带方向,有时断层面倾角会变化,直至倾向相反(丝带效应);走滑断裂带各点所受的应力可从挤压(褶皱)—逆断变为伸展—正断(海豚效应)。走滑断裂在火山岩盆地中普遍发育,是构造—火山作用关系研究的重要方面。研究区走滑断裂系统由贯通性主干走滑断裂和伴生构造两部分组成。主干走滑断裂平面上侧向延伸长,其附近多为与之成锐角相交的雁列正断层组;剖面上同时出现负花状构造和正花状构造,断层面陡倾且有时两侧地层厚度不等。根据雁列构造与主干断层间锐角指示方向和断层切割层位可判别,该区于古近纪主要发育右旋走滑断裂系。火山岩分布明显受走滑断裂带控制,火山喷发中心沿主干断裂呈串珠状分布;火山岩厚度于主干断裂附近最大,向两侧减薄,多终止于次级断裂附近;厚度大于1 km的火山岩距主干断裂通常在2 km范围内。Strike-slip can be divided into two types： pressure torsion and tensional torsional, on the plane, both of their main strike-slip fault shows a thorough strike-slip fauh, in profiles, the former showed positive flower structure （the thrust upward reverse fault group）, the latter showed negative flower structure （the thrust upward normal fault group）. They behave in the plane with the main strike-slip fault symbiotic echelon folds, echelon reverse fault（ pressure torsion） and echelon normal faults （tensional torsional）. Due to the changes of tectonic stress field the Complex flower structure which is made up of Positive flower structure and negative flower structure can always be seen in actual profiles. In parallel with the direction of the strike-slip fault, sometimes fault plane tendency will change, until contrary （ ribbon effect） ; on the direction of the strike-slip fault the stress change from the extrusion / fold, reverse fault into the stretch / normal fault （dolphin effect）. Strike-slip fault universally developed in volcanic basins, are important aspect of analyzing the relationship of tectonic and volcanism. Strike- slip fault system in the study area consists of the cross-cutting main fault and associated echelon structures. The main strike-slip fault are characterized by long extension on the plane, the echelon normal fault group intersected it with an acute angle which developed in the nearby area; in profiles simultaneously developed negative flower structures and positive flower structures, fault plane steeply dipping and both sides of formation thickness different sometimes. According echelon structures with an acute angle between the direction of the main fault and the layers which the fault cut, can infer this area mainly developed dextral strike-slip fault system in the Paleogene. Volcanic rocks was significantly affected by strike-slip fault zone, volcanic eruption center beaded distribution along the main fault ; the maximum thickness of volcanic rocks near the main

关 键 词：辽河火山岩盆地 构造火山作用 走滑断裂系统 花状构造 雁列构造 

分 类 号：P588.14[天文地球—岩石学] P542[天文地球—地质学]