Collaborative Research: SERPENT: Serpentinite, Extension and Regional Porosity Experiment across the Nicaraguan Trench

合作研究：SERPENT：尼加拉瓜海沟的蛇纹岩、延伸和区域孔隙度实验

• 批准号: 0841114
• 负责人: Steven Constable
• 金额: $ 70万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0841114&HistoricalAwards=false
• 关键词: Collaborative; Research; SERPENT; Serpentinite; Extension

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The thin, rocky shell of the Earth, the lithosphere, is broken into a mosaic of thin plates that are inconstant motion. Along some boundaries between plates, one slides beneath the other and is consumed in a process known as subduction. Most of great earthquakes and violent volcanic eruptions occur at subduction zones. Both of these processes are significantly affected by the amount of water that is carried into the interior with the downgoing plate, but these processes remain poorly understood because the amount of water entering the subduction system remains poorly constrained. A major carrier of water is the mineral serpentine, and one of the major uncertainties is the volume of water that is being carried into the subduction system by serpentinized upper mantle. Electromagnetic geophysical methods are sensitive to the presence and concentration of water at depth in the Earth. This project consists of a large-scale electromagnetic experiment along a 300 km profile off Nicaragua in a region that shows evidence for substantial fault related fluid circulation in the crust and possibly in the upper mantle, and high Ba/La ratios and water contents in adjacent onshore volcanics suggesting a strong slab fluid input into the arc-melting. This survey will combine controlled-source electromagnetics (CSEM) with broadband and long period magnetotellurics (MT) to provide a comprehensive picture of the conductivity structure from the seafloor to the upper mantle, representing the entire input into this part of the Central American subduction zone. In addition to the societal relevance of improving our understanding of processes that produce earthquakes and volcanic eruptions, this project will promote international scientific cooperation and support two Ph.D. students.

该奖项是根据2009年的《美国回收与再投资法》（公法111-5）资助的。地球上稀薄的岩石外壳（岩石圈）被分解为薄板的马赛克，这是不一致的运动。沿着板之间的某些边界，一个滑动在另一个板块下面，并在称为俯冲的过程中消耗。大多数巨大的地震和暴力火山喷发发生在俯冲区。这两个过程都受到带有下部板的水量的显着影响，但是由于进入俯冲系统的水量仍然很差，因此这些过程仍然很少了解。主要水的主要载体是矿物蛇纹石，主要不确定性之一是通过蛇形上层地幔运送到俯冲系统中的水量。电磁地球物理方法对地球深度的水的存在和浓度敏感。该项目由一个沿尼加拉瓜的300公里轮廓的大规模电磁实验组成，该区域显示了在地壳中以及可能在上地幔中的实质性断层相关的流体循环的证据，以及在邻近的陆上火山中的高BA/LA比和水含量，暗示强烈的Slab Bimcanic，表明将静态液体输入到弧形中。 这项调查将将受控的源电磁学（CSEM）与宽带和长期磁铁电磁（MT）相结合，以提供从海底到上地幔的电导率结构的全面图片，代表了全美俯冲区的整个输入。除了提高我们对产生地震和火山喷发过程的理解的社会相关性外，该项目还将促进国际科学合作并支持两位博士学位。学生。