| 横过西昆仑和塔里木结合带的山隆盆降机制动力学模拟 |
| |
| 关键词:mountain rising and basin sinking lithospheric root FE numerical modeling dynamical evolution |
| 基金项目:国土资源部中国岩石圈三维结构专项计划(200010101-13)，国家自然科学基金重点项目(49834002)，中国科学院动力大地测量学开放研究实验室基金(L21-05)，国家新疆305项目(96-915-07-03)，国家重点基础研究发展规划项目(G1998040806) |
|
| 摘要点击次数: 3784 |
| 全文下载次数: 2579 |
| 摘要: |
| Modelling of the Evolution of Collision Mountain Range across the Contact Zone between West Kunlun and Tarim |
| Evidence for the existence of a massive deep-seated lithospheric root beneath the contact zone between West Kunlun and Tarim has recently been recognized on the basis of deep seismic reflection and broadband seismic exploration. It is explained as follows: the convergence of Indian Plate and Asian Plate caused crustal thickening and associated isostatic uplift of the mountain range; to accommodate the lithospheric convergence, the cool topmost mantle (subcrustal lithosphere) should also have thickened and sinked downwards when it was subducted into the underlying mantle. The tectonic finite element computer package FEVPLIB (Zhang and Bott, 2000) was used to model the evolution of collision mountain range across the contact zone. The finite element grid used was 1000 km long and extended to the depth of 650 km. The western Kunlun thrust belt (WKTB) dipping southward was centered at the submountain region of West Kunlun. The stress distribution for five stages of sinking of the lithospheric root was modeled. The results show that there are two opposing stress systems along the contact zone. The surface loading of the mountain and the associated root of thickened crust produced horizontal deviatoric tension in the strong upper crust in the south of the WKTB (90 MPa at Stage 4). In contrast, the deep and dense lithospheric root and its associated downflexing of the surface produced horizontal compressive deviatoric stress in the strong upper crust in the north of the WKTB (100 MPa at Stage 4). It is concluded that the sinking lithospheric root produced a collision pull force which developed West Kunlun mountain range, and surface downflexure formed by the root down pull may have given rise to Tarim Basin. |
| ZHANG Gui-bin,GAO Rui,XIAO Xu-chang.2001.Modelling of the Evolution of Collision Mountain Range across the Contact Zone between West Kunlun and Tarim[J].Acta Geoscientica Sinica,22(6):541-546. |
| 查看全文 查看/发表评论 下载PDF阅读器 |