Lithospheric Structure and Deformation of the Flat Slab Region of Argentina

阿根廷平板区岩石圈结构与变形

• 批准号: 0510966
• 负责人: Susan Beck
• 金额: $ 54.75万
• 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: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0510966&HistoricalAwards=false
• 关键词: Lithospheric; Structure; Deformation; Flat; Slab; Lithospheric; Structure; Deformation; Flat; Slab

Major advances have occurred in our understanding of thin-skinned thrust belts and plateau systems in both collisional and noncollisional mountain belts. However, our understanding of how thick-skinned deformation forms in a tectonic setting of flat subduction has lagged behind. Similarly much progress has been made in the study of subduction zone processes but we still lack a clear understanding of what controls flat slab subduction and the impact on mantle processes. One of the best places in theworld to study the link between flat subduction and continental deformation is in the Precordillera and Sierras Pampeanas of western Argentina. In this project, the investigators propose to use all existing seismic data and collect additional data with a 40-station broadband seismic deployment for high resolution imaging of the Sierras Pampeanas and the flat slab. They will build on results from their previous work in Argentina in the CHARGE project to answer a number of questions about flat subduction and the deformation of the foreland basement. Among the broader impacts of this proposal are improving the international collaboration among seismologists from the National University in San Juan, Argentina, Chile and France and the training of graduate and undergraduate students. The Sierras Pampeanas of Argentina have a very high rate of crustal seismicity and have a history of devastating magnitude 7 earthquakes (1944, 1977). This study will contribute to a better understanding of earthquakes hazards and directly improve earthquake locations and source studies in the region by providing better velocity models. The results will be important for the study of the Laramide deformation in the western U.S., one of the stated objectives for Earthscope science.

在碰撞和非碰撞山带中，我们对薄皮的推力皮带和高原系统的理解发生了重大进展。但是，我们对扁平俯冲构造环境中厚皮变形的理解已落后。同样，在俯冲带过程的研究中也取得了很多进展，但我们仍然对控制平板俯冲的原因以及对地幔过程的影响缺乏清晰的了解。研究平坦俯冲和大陆变形之间联系的世界上最好的地方之一是阿根廷西部的Precordillera和Sierras Pampeanas。在该项目中，研究人员建议使用所有现有的地震数据，并收集40个宽带地震部署的其他数据，以对Sierras Pampeanas和Flat Slab进行高分辨率成像。他们将基于他们先前在阿根廷的收费项目中的工作的结果，以回答有关俯冲和前陆地下室变形的许多问题。该提案的更广泛的影响之一是改善了圣胡安，阿根廷，智利和法国的国立大学的西马学家之间的国际合作以及对研究生和本科生的培训。阿根廷的Sierras Pampeanas具有很高的地壳地震速度，并且具有毁灭性的7级地震史（1944，1977）。这项研究将有助于更好地了解地震危害，并通过提供更好的速度模型来直接改善该地区的地震位置和来源研究。结果对于研究美国西部的Laramide变形的研究将很重要，这是Earthscope Science的既定目标之一。