大陆岩石圈挠曲背景下盆山耦合研究进展与展望  

Progress and perspective of coupled evolution of orogens and sedimentary basins due to continental lithospheric flexure

作　　者：程丰[1] 彭景臻 王林 郭召杰[1] CHENG Feng;PENG Jingzhen;WANG Lin;GUO Zhaojie(School of Earth and Space Sciences,Peking University,Beijing 100871,China;Department of Civil and Environment,the Hong Kong University of Science and Technology,Hong Kong 999077,China)

机构地区：[1]北京大学地球与空间科学学院,北京100871 [2]香港科技大学土木与环境工程系,中国香港999077

出　　处：《地质学报》2023年第9期2927-2938,共12页Acta Geologica Sinica

基　　金：国家自然科学基金项目(编号U22B6002)资助的成果。

摘　　要：盆山耦合研究在大地构造和地球动力学研究中占有重要地位。地貌负载引起的大陆岩石圈挠曲与沉积盆地沉降是盆山耦合的一种重要体现方式。本论文聚焦于挤压背景下大陆岩石圈挠曲盆地与造山带的耦合过程,系统梳理了单个或者多个地貌负载的几何形态、挠曲盆地几何形态以及岩石圈有效弹性厚度(T_(e))三者之间的数学关系。在此基础上,论文介绍了岩石圈挠曲模拟方法在恢复岩石圈刚性程度、造山带演化过程以及盆地沉积沉降方面的具体应用。结合古环境分析与岩石圈挠曲模拟实验,本文提出了一种定量恢复造山带古海拔的新方法。有别于基于温度、压力以及动植物分布与海拔之间关系所建立的传统古高度计,该方法强调在海侵时期地貌负载与沉积盆地间的高度差即为造山带的古海拔。该方法的提出为重建中亚以及其他曾受海侵影响并与岩石圈挠曲相关造山带的古海拔提供了新的思路。论文最后介绍了岩石圈挠曲模拟在定量分析造山带与盆地演化的研究过程中存在的问题与不足,并提出了在探究沉积盆地基底属性、重建岩石圈挠曲相关造山带古海拔以及有关挠曲模拟软件开发方面的新展望。Determining the relationship between the orogens and sedimentary basins is an important aspect of tectonics and geodynamics research.This is well-exemplified by the coupling between the orogens and sedimentary basin due to continental lithospheric flexure.This contribution focuses on the continental lithospheric flexure and shows the relationship between the shape of the single or multiple topographic loads,the shape of the flexural basin,and the effective elastic thickness(Te).Based on theory and case studies,this study shows how flexural modeling applies to research associated with the orogens and sedimentary basin evolution.By combining paleoenvironment indicators with flexural modeling,we also propose a novel approach to quantitatively estimate the paleoelevation of an orogenic belt that accounts for the flexural subsidence of a basin that was influenced by sea incursion.Different from other paleoaltimetry approaches that connect the temperature or pressure and elevation,this new approach emphasizes that the relief of the topographic load equals the paleoelevation of the orogenic belt during the time when the sea incursion occurs in the flexural basin,providing a new way to understand the paleoelevation of the orogenic belts.Finally,this work summarizes the caveats of flexural modeling and gives some new perspectives on documenting the basement feature of sedimentary basins,paleoelevation reconstruction,and the design and application of the software associated with flexural modeling.

关 键 词：盆山耦合 岩石圈挠曲 岩石圈有效地壳厚度 古海拔重建 青藏高原 

分 类 号：P542[天文地球—构造地质学]