Collaborative Research: Lithosphere Structure and Evolutionof the Rocky Mountain Transect of the Western U.S: An Integrated Geological and Geophysical Investigation

合作研究：美国西部落基山脉横断面的岩石圈结构和演化：综合地质和地球物理调查

• 批准号: 9614862
• 负责人: Scott Smithson
• 金额: $ 55.48万
• 依托单位: University of Wyoming
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-12-15 至 2001-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9614862&HistoricalAwards=false
• 关键词: Collaborative; Research; Lithosphere; Structure; Evolutionof

9614862 Smithson This collaborative study is aimed at understanding the evolution of the lithosphere of the Rocky Mountain transect in the North American southwest. This transect is located at the juncture of two globally-unique tectonic regimes, each of fundamental importance for understanding continental tectonics and together representing an outstanding field laboratory for studies of continental lithosphere. First, a 1000 km wide juvenile Proterozoic orogenic belt records rapid accretion of continental materials from mantle sources and their assembly to southern Laurentia along NE-trending boundaries between 1.8 and 1.6 Ga. Second, the present high elevation of the SW in general and the Rocky Mountains in particular is the manifestation of Laramide, Tertiary, and still ongoing modification of Proterozoic Lithosphere that has resulted in a wide NW-trending mantle boundary zone between old, cold, high velocity mantle in the continental interior and hotter, lower velocity mantle in the western U.S. By examining the present-day lithospheric structure across ancient boundaries, the P.I.s hope to better understand the interplay between "active" and "passive" processes during lithospheric evolution. Their principal hypothesis is that lithospheric structures produced during assembly of the southwestern U.S. have profoundly influenced physical and chemical modification of the continental lithosphere during all subsequent magmatic and tectonic events, including those related to the ongoing reorganization of small-scale asthenospheric convection and replacement of lithosphere by asthenosphere. To test this hypothesis, they propose an integrated set of multi-scale experiments using state of the art geophysical, geological and geochemical techniques that, together, are designed to decipher lithosphere structure and evolution, and processes of lithosphere formation and deformation. ***

9614862 Smithson这项合作研究旨在了解北美西南岩石山脉岩石圈的演变。 该横断面位于两个全球唯一的构造政权的关头，这对于理解大陆构造学的每个基本重要性，共同代表了大陆岩石圈研究的出色现场实验室。 首先，一个1000公里宽的幼年properoroc造山带记录了大陆材料从地幔源及其组装到南部laurentia沿NE趋势界限的迅速增值，其次是1.8至1.6 ga。 NW趋势在大陆内部和热较高的旧，冷，高速地幔之间，通过检查古代边界的当今岩石圈结构，希望更好地理解“活跃”和“主动”之间的相互作用，并在岩石层循环过程中更好地理解相互作用。 他们的主要假设是，在美国西南部组装过程中产生的岩石圈结构在所有随后的岩浆和构造事件中都深远影响了大陆岩石圈的物理和化学修饰，包括与正在进行的小尺度的阿瑟磷酸对流和质地替代小层层次对流和替代岩石圈的更换相关的事件。 为了检验这一假设，他们提出了一组综合的多尺度实验集，它使用最先进的地球物理，地质和地球化学技术，共同设计为解密岩石圈结构和进化，以及岩石圈形成和变形的过程。 ***