地壳均衡理论及其在构造地貌研究中的应用  

Isostasy and its application in tectonic geomorphology research

作　　者：舒远海 石许华 陈汉林[1] 杨蓉[1] 林秀斌[1] 程晓敢[1] 吴磊[1] 龚俊峰 邓洪旦 白卓娜 王锦涵 SHU Yuanhai;SHI Xuhua;CHEN Hanlin;YANG Rong;LIN Xubin;CHENG Xiaogan;WU Lei;GONG Junfeng;DENG Hongdan;BAI Zhuona;WANG Jinhan(Key Laboratory of Geoscience Big Data and Deep Resource of Zhejiang Prorince,School of Earh Sciences,Zhejiang Unirersily Hangzhou,310027)

机构地区：[1]浙江省地学大数据与地球深部资源重点实验室,浙江大学地球科学学院,杭州310027

出　　处：《地质论评》2022年第4期1171-1190,共20页Geological Review

基　　金：国家自然科学基金资助项目(编号:41941016,41720104003,41972227,41972214,42002219,41902204);浙江省钱江人才项目(编号:D类计划QJD1902023);浙大百人计划项目;中央高校基本科研业务专项资金资助项目(编号:2021XZZX005)的成果。

摘　　要：地壳均衡是地球科学的一个基本概念,其理论基础为“轻地壳(密度较小)漂浮在重地幔(较稠密)之上”。均衡理论(如冲压假说、弹性板理论等)和模型(如Airy模型、Pratt模型及弹性板模型等)的产生及发展对研究岩石圈流变学性质、圈层相互作用及造山作用等地球动力学过程有着重要意义。本文总结了相关均衡理论、模型及计算方法,并结合其在不同空间尺度构造地貌现象研究中的运用,包括:(1)冰川均衡调整研究中不同模型的优化及其对全球海平面变化的指示意义、(2)阐明海山洋岛发育过程及其制约因素、(3)利用弹性板模型重建山脉隆升和盆地挠曲沉降史并进一步探讨二者之间的相互作用、(4)通过研究变形湖滨线有效地约束地球的相关物理参数、(5)建立河流三角洲发育特征模型并服务于现代社会经济、(6)揭示水库蓄水导致的地壳挠曲变形与浅部地质灾害发育的关系及(7)同震滑坡对局部地貌改造的影响,讨论并展望了未来地壳均衡在构造地貌学领域的发展方向,即结合高精度大地测量技术与地质年代学方法,定量地解决构造地貌研究中的关键问题,更全面、系统地了解地表过程、地球深部过程与动力学和地球圈层之间的相互作用。Isostasy is a fundamental concept in Earth Sciences,based on the idea that a lighter crust floats on a denser mantle.The emergence and development of isostatic theories(e.g.,Punching Hypothesis and Elastic Plate Theory)and models(e.g.,Airy model,Pratt model and Flexure model)are of great significance for the study of geodynamic processes,such as the rheological properties of the lithosphere,interactions between the Earth′s spheres and orogenesis.We summarized the isostatic theories,classical models and calculation methods and its application in tectonic geomorphology on variable spatial scales.These examples include the optimization of different glacier isostatic rebound models and its significance to the implication of global sea level change,clarifying the development process and restricting factors of seamounts and ocean islands,using the elastic plate models to reconstruct the history of mountain uplift and basin flexural subsidence and further exploring the interaction between them,constraining physical parameters of the earth according to the shoreline deflection,building the river delta development model to service in the modern social economy,revealing the relationship between the crust flexural deformation caused by reservoir impoundment and the development of geohazards,and coseismic landslides′influence on local landscape evolution.Finally,we discussed and prospected the future development direction of isostasy in tectonic geomorphology research,that is to solve the problems of key areas quantitatively by combining with high-precision geodesy and geochronology methods,and further study the interaction among surface processes,deep earth processes and dynamics,of the Earth′s spheres,comprehensively and systematically.

关 键 词：地壳均衡 均衡模型 有效弹性厚度 弹性板 构造地貌 

分 类 号：P931[天文地球—自然地理学] P542