莺歌海盆地形成的约束条件及动力学模式  

Constraint Conditions and Dynamic Models for the Forming of Yinggehai Basin

作　　者：关成尧[1,2] 赵国春[2] 刘翠[2] 白相东[1] GUAN Cheng yao;ZHAO Guo chun;LIU Cui;BAI Xiang dong(Department of Earthquake Science, Institute of Disaster Prevention Science and Technology,Sanhe 065201, P. R. China;School of Earth Sciences and Resources,China University of Geosciences (Beijing),Beijing 100083,P.R.China)

机构地区：[1]防灾科技学院地震科学系,三河065201 [2]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《科学技术与工程》2017年第29期8-18,共11页Science Technology and Engineering

基　　金：中国地震局教师科研基金(20150103);中国地质调查局国土资源实物资料中心协作项目(2013-B-211);河北省高等学校人文社会科学研究重点项目(SD162001)资助

摘　　要：莺歌海盆地的形成机制是理解南海构造演化和印支半岛构造演化的枢纽。一般认为莺歌海盆地为走滑拉分盆地。根据盆地分析表明莺歌海经过多期升降的特点,通过总结前人认识成果,确定盆地研究的约束条件;并指出莺歌海运动模式之确定应考虑的外围边界条件。以这些约束条件和外围边界力学条件为基础,讨论了莺歌海-印支地块活动模式的7种体制模式;并结合围区的主要事件序列,认为在38~25 Ma期间,主要是印支地块挤出和南海西北海盆的扩张导致的南海西缘断裂的左行走滑的运动;25~15 Ma之间,莺歌海围区的构造主要是西南次海盆的扩张,导致南海西缘断裂的右行走滑,莺歌海盆地反转;15~5.5 Ma之间的活动特性很可能是一个过渡,或者存在南北方向的伸展;而在5.5 Ma之后,红河断裂的右行走滑造就了莺歌海盆地的走滑拉分形貌。莺歌海盆地形成的主要机制不为走滑拉分,而是边界摩擦作用下的南北向伸展为主的被动伸展的窄裂谷盆地。The formation mechanism of Yinggehai Basin is the core of that to understand the tectonic evolution of the South China Sea and the Indosinian Peninsula tectonic evolution of the hub,generally believed that Yinggehai Basin is a strike slip pull apart basin.According to basin analysis,the Yinggehai basin had some multi phase movements.It is concluded that the boundary conditionsof Yinggehai which some dynamic model should be taken into account in determining the constraint conditions of basin study Based on the constraints and external mechanics conditions,7models of the Yinggehai Indosinian block activity pattern,were discussed and combined with the main sequence of the events It is considered that during the period of38~25Ma,The movement of the left lateral strike slip of the South China SeaWestern Margin Fault,between25Ma and15Ma,thatis due to the expansion of the southwestern sub basin,leading to the right lateral strike slip of the South China SeaWestern Margin Fault The reversal of the Yinggehaibasin is likely to be a transitional feature between15Ma and5.5Ma,Or there is a north south extension After5.5Ma,the strike slip profile of the Yinghehai basin is formed by the right lateral slip of the Honghe Fault The main mechanism for the formation of Yinggehai Basin is not the pull apart of strike slip,but the extension of narrow rift basins with south north extension under boundary friction

关 键 词：莺歌海 盆地类型 边界摩擦裂谷 动力学模式 约束条件 

分 类 号：P56[天文地球—构造地质学]