Collaborative Research: St. Elias Erosion/Tectonics Project (STEEP)

合作研究：圣埃利亚斯侵蚀/构造项目 (STEEP)

• 批准号: 0409351
• 负责人: Gary Pavlis
• 金额: --
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-15 至 2010-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0409351&HistoricalAwards=false
• 关键词: Collaborative; Research; St.; Elias; Erosion

0409351PavlisThis is a multi-disciplinary study to address the evolution of the highest coastal mountain range on Earth - the St. Elias Mountains of southern Alaska and northwestern Canada. This orogen has developed over the past few million years as the Yakutat block, a continental-oceanic terrane, has attempted subduction beneath the eastern end of the Aleutian arc-trench system. The ~500 km-long, 150 km-wide St. Elias mountain range is the product of the dynamic balance between rapid uplift induced by crustal convergence and rapid exhumation by a regional system of large, fast-moving temperate glaciers. Most sediments are deposited either on a broad shelf or in deepsea fans and provide a complete record of the tectonic, climatic, erosional, and eustatic events that have accompanied the orogeny. The overarching goal of the project is to develop a comprehensive model for the St. Elias orogen that accounts for the interaction of regional plate tectonic processes, structural development, and rapid erosion. The focus of the study is on the partitioning of deformation within the system from upper mantle flow to near-surface faulting and exhumation. The study will investigate the geodynamics of oblique collision under a set of conditions that will allow the PIs to address several important and fundamental questions:- Has intense Quaternary glacial erosion redistributed mass in the orogen sufficiently to change regional deformational patterns, and has focused erosion along deep glacial valleys been sufficient to localize crustal strains?- How is deformation partitioned into lithospheric shortening and uplift versus lateral extrusion of the detached crust, and does intense erosion influence this partitioning?- Is the orogeny driven primarily by subduction of a buoyant oceanic plateau or by collision of a small microcontinental block attached to allochthonous ocean crust?Addressing these questions has broad implications for understanding the geodynamics of oblique collision in general, the role of different mechanisms in development of far-field orogenic effects, and the control of erosion on development of slip partitioning during oblique convergence. The project also has general implications for how subduction/accretion of small continental terranes versus oceanic plateaus contribute to deformation of the continents, and ultimately the fate of these fragments in construction of the crustal collage which is typical of virtually all continents. Specifically, the P.I.s propose a multidisciplinary approach involving seismologists (subsurface imaging and seismicity), geologists, geodesists, glaciologists, geochronologists, and geodynamic modelers.

0409351Pavlisthis是一项多学科研究，旨在解决地球上沿海山脉最高的山脉的演变 - 阿拉斯加南部和加拿大西北部的圣埃利亚斯山脉。 在过去的几百万年中，这种基因的发展已发展，因为Yakutat块是一种大陆环境地层，试图在Aleutian Arc-Trench系统的东端下方俯冲。 约500公里长的150公里宽的圣埃利亚斯山脉是地壳收敛引起的快速提升与通过大型，快速移动的温带冰川的区域系统诱导的快速提升之间的动态平衡的产物。 大多数沉积物都沉积在宽阔的架子上或深海风扇中，并提供伴随造山基因的构造，气候，侵蚀性和eust性事件的完整记录。 该项目的总体目标是为圣埃利亚斯造山带开发一个综合模型，该模型解释了区域板块构造过程，结构发展和快速侵蚀的相互作用。 该研究的重点是从地幔流到近地面断层和挖掘的系统内变形的划分。 该研究将调查在一组条件下倾斜碰撞的地球动力学，这些条件将使PI可以解决几个重要的和基本的问题： - 在造山基因中充分充分改变了造成的造成造成的巨大的四分之一的冰川侵蚀重新分布，足以改变区域变形模式，并沿着深层裂口沿着深层的构造构成了构造的构造，并已足够的侵蚀 - 脱离的地壳的挤出与横向挤出，强烈的侵蚀会影响这种分配吗？ - 造成造成的造成驱动是主要是由浮力的海洋高原的俯冲俯冲，还是碰撞的小微区块附着在同种海洋上的小微区块？解决这些问题的广泛含义？解决这些问题的范围广泛，理解了构成的态度，从而构成了越来越不同的作用。控制侵蚀在倾斜收敛期间滑动分配的发展。 该项目还对小型大陆台与海洋高原的俯冲/积聚也有一般的影响，这是如何有助于大陆变形的，最终是这些碎片在构造地壳拼贴时的命运，这实际上是所有大陆的典型代表。 具体而言，P.I.S提出了一种涉及地震学家（地下成像和地震性）的多学科方法，地质学家，地质学家，冰川学家，地球文学家和地球动力学建模者。