塔里木盆地顺托果勒地区早中志留世震积岩——高分辨构造事件的记录

发布时间：2018-04-18 22:21

本文选题：软沉积变形构造 + 震积岩　；参考：《地球学报》2016年03期

【摘要】：在塔里木盆地塔中隆起与满加尔坳陷结合部——顺托果勒地区的深钻井岩心中,发现了大量早中志留世软沉积变形构造。其中主要包括液化砂岩脉、液化角砾岩、触变底劈构造、触变楔、负载构造、球-枕构造和复合混插构造等。通过系统地观察软沉积变形构造的岩石组成、构造形貌及样式、垂向分布的循环性、横向分布的延展性、沉积环境及与古活动断裂的关系,确定其为震积岩。结合该区断裂早中志留世的发育特征,推测发震断裂主要可能是塔中隆起与满加尔坳陷结合部的北东向走滑逆冲断裂以及北西向剪切拉张断裂。在早志留世柯坪塔格组沉积时约4 Ma中最少发生了26次古地震事件(震级M5)。这些古地震记录不仅反映了研究区志留纪构造的活动性,也是弥补主构造运动中高频次构造事件脉动性、循环性的重要证据,为重建中古生代的古构造提供新的线索。
[Abstract]:A large number of early and middle Silurian soft sedimentary deformation structures were found in the deep drilling core of Shuntogol area, the junction of Tazhong uplift and Mangar depression in Tarim Basin.It mainly includes liquefaction sandstone vein, liquefaction breccia, thixotropic bottom wedge, thixotropic wedge, load structure, ball pillow structure and composite intercalation structure.By observing systematically the rock composition, the structural morphology and style, the circulation of vertical distribution, the ductility of transverse distribution, the sedimentary environment and the relationship with paleoactive faults, it is determined that the soft sedimentary deformed structure is seismogenic.Based on the early Middle Silurian characteristics of the faults in this area, it is inferred that the main seismogenic faults are the NE strike slip thrust faults and the NW shear extensional faults at the junction of the Tazhong uplift and the Manchar depression.At least 26 paleoearthquakes (M _ 5 M _ 5) occurred in the early Silurian Kepingtag formation during the depositional period of about 4 Ma.These paleoseismic records not only reflect the activity of Silurian structures in the study area, but also provide important evidence for the pulsation and cyclicity of high frequency tectonic events in the main tectonic movement, and provide new clues for the reconstruction of paleotectonics in the Middle Paleozoic.
【作者单位】：中国地质科学院地质研究所;中国石油化工股份有限公司石油勘探开发研究院;中国石化西北油田分公司研究院;中国石油大学;
【基金】：中石化西北分公司科研项目(编号:KY2013-S-024) 中国地质调查局项目(编号:12120115002001;12120115026901) 国土资源部行业基金项目(编号:201011034) 国家自然科学创新团队基金(编号:40921001)联合资助
【分类号】：P542

【相似文献】