Cretaceous-Earliest Tertiary Basin Development, Deformation, and Magmatism in Southern Tibet: Implications for Pre-Indo-Asian Collision Lithospheric Structure

藏南白垩纪-最早第三纪盆地的发育、变形和岩浆作用：对印支前碰撞岩石圈结构的影响

• 批准号: 0309844
• 负责人: Paul Kapp
• 金额: $ 24.77万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2006-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0309844&HistoricalAwards=false
• 关键词: Cretaceous; Earliest; Tertiary; Basin; Development

How are continental collisional orogens preconditioned by tectonic processes that operate along convergent margins prior to the collisional events? The Tibetan plateau, which is generally accepted as the archetype of collisional orogens, is a perfect natural laboratory to study this question because it contains a record of pre-collisional, Andean-style arc-related tectonics as well as collisional tectonics during the Cenozoic. General models for Tibetan Plateau evolution begin with assumptions of initial conditions for crustal thickness and mantle structure that strongly influence the results of the models. However, geological support for these assumptions is scarce. This study is integrating geologic mapping and structural, stratigraphic, sedimentologic, and geochronologic studies of widely exposed Cretaceous and earliest Tertiary basin fill and igneous rocks in the Lhasa terrane of southern Tibet to provide new constraints on the pre-collisional history of strain, basin development, paleogeography, denudation, and magmatism. It is hoped that integration of these new constraints with previous studies will lead to a unified tectonic model that provides realistic initial conditions for the lithospheric structure of southern Tibet prior to the Indo-Asian collision. The results should have broad implications for models of Cenozoic orogeny in central Asia, as well as collisional orogenesis in general.

在碰撞事件之前，通过沿收敛边缘运行的构造过程对大陆碰撞的Orogens进行了预处理？ 藏族高原普遍被认为是碰撞or蛋白的原型，是研究这个问题的理想天然实验室，因为它包含了coll胶的记录，并在康内生代期间记录了与安第斯式ARC型弧相关的构造以及碰撞的构造。 藏族高原进化的一般模型始于对地壳厚度和地幔结构的初始条件的假设，这些条件强烈影响模型的结果。 但是，对这些假设的地质支持是稀缺的。 这项研究是在西藏南部的Lhasa Terrane中整合地质图和结构性，地层，沉积学和地质研究研究，并在西藏南部的Lhasa Terrane中填充和火成岩岩石，以提供有关紧张，盆地发展，古地地理，剥夺，玛格诺和杂志的新限制。 希望这些新约束与以前的研究的整合将导致统一的构造模型，该模型为印度亚洲碰撞之前的西藏南部的岩石圈结构提供了现实的初始条件。 结果应该对中亚的新生代造山运动的模型以及一般的碰撞造山学具有广泛的影响。