新生代大陆板内伸展盆—山耦合与大陆碰撞效应——以渤海湾盆地济阳坳陷、周缘隆起及边界断裂构造演化为例

新生代印欧大陆碰撞引发了中国西部前缘大规模多阶段地壳挤压缩短、构造变形与隆升及岩浆事件,在中国东部,新生代山脉的抬升、盆地的伸展、沉降,以及郯庐断裂带新生代的活动与青藏高原的隆升具有准同时性,伸展盆地—伸展山脉之间存在耦合关系。这种对应关系呈"幕式"变化,主要表现在印欧大陆碰撞岩石圈增厚、构造变形和抬升的高峰时期,对应盆地岩石圈伸展、减薄、快速构造沉降以及郯庐断裂带活动等阶段,当构造转入相对稳定(松弛)时期,表现为高原剥蚀夷平、岩浆活动频繁以及盆地构造沉降速率减缓等阶段。从全球板块构造的角度来看,中国西部、东部新生代挤压、伸展和走滑活动属同一动力学体系条件下的耦合关系,驱动力可能是两大板块碰撞、深部地幔脉动上涌以及新生代太平洋板块与欧亚板块俯冲和速率变化的共同作用。

Cenozoic continental intraplate extension basin-mountain coupling and continental collision:Evidences from Bohai Bay Basin,its peripheral mountain and Tancheng-Lujiang fault

Cenozoic Indian-Asia continental collision induced a large scale of multiple intensive compress-shortening in foreland West China.However,in southern of the Bohai Bay Basin-Jiyang Depression,its peripheral West Shandong Rise(WSR) and boundary Tancheng-Lujiang Fault(TLF) of North China,the deformation-sedimentary-magmatism events showed a penecontemporaneous reverse characteristics with rapid subsidence,lithosphere thinning and basin subsided.The peak stage of the lithosphere thickening and plateau been raised is in coherent with the peak stage of lithosphere thinning,rapid basin subsidence and the TLF movement.Alternative stage is the frequent magmatism,structural relax deformation with plateau denudation and basin relative slow subsidence.Focus on the global view,the thermal effect resulted from the mantle upwelling induced by the two continent collision,together with the change of the subduction direction and rate between the Pacific Plate and Eurasia might be the motivation of the West and East of China deformation style.