Acquisition and Operation of Broadband Seismograph Equipment at Chilean Bases in the Antarctic Peninsula Region

该奖项由极地项目办公室的南极地质和地球物理项目联合提供，支持将南极半岛的三个临时地震仪改造成半永久性台站的研究，并利用这些数据继续进行基础研究。在1997年和1998年期间，在南极半岛地区和智利巴塔哥尼亚最南端安装和维护了一个由11个宽带地震仪组成的网络。从这个项目返回的数据是优秀的和有趣的初步结果已经产生。这些仪器在较长时间内的持续运行将是非常有益的，因为较大震级的区域地震的数量很少，因此需要较长的时间来获取数据。但是，该项目的仪器是从IRIS-PASSCAL仪器池借用的，必须在1999年4月归还给PASSCAL。这笔资金将用于把智利在南极的永久基地的三个台站改造为永久台站，并继续对该地区进行为期四年的地震调查。作为该项目的一部分，位于智利巴塔哥尼亚的第四个站将继续使用华盛顿大学的设备运作。该项目的资助将使华盛顿大学和智利大学在这些台站的运作方面继续合作，数据将转交给IRIS数据中心以及其他国际地震合作者。与南极地震学研究项目的其他国家团体的相互数据交换将提供从该地区各种其他专有宽带站获取宽带数据的途径。这些数据将用于研究该地区几个复杂构造区域的地震活动性和上地幔速度结构，包括南设得兰俯冲带、布兰斯菲尔德弧后裂谷、巴塔哥尼亚、德雷克海峡和南斯科舍脊的扩散板块边界。特别是，这些台站在更长的时间内的运行将使我们更好地了解南设得兰海沟的地震活动，这是一个不寻常的俯冲带，表明年轻岩石圈的俯冲非常缓慢。这些地震仪还将用于记录布兰斯菲尔德海峡地球物理巡航期间的气枪射击，这是由德克萨斯大学计划于2000年4月进行的。这些数据将对台站下面的地壳结构提供重要的约束条件，改进的结构模型将能够实施更精确的地震定位程序，以支持对该地区的地震学理解。

This award, provided jointly by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to transform three temporary seismometers in the Antarctic Peninsula into semi-permanent stations and to continue basic research using these data. During 1997 and 1998, a network of 11 broadband seismographs in the Antarctic Peninsula region and southernmost Chilean Patagonia were installed and maintained. Data return from this project has been excellent and interesting initial results have been produced. The continued operation of these instruments over a longer time period would be highly beneficial because the number of larger magnitude regional earthquakes is small and so a longer time is needed to acquire data. However, instruments from this project are borrowed from the IRIS-PASSCAL instrument pool and must be returned to PASSCAL in April, 1999. This award provides funds to convert three stations at permanent Chilean bases in the Antarctic to permanent stations, and to continue the seismological investigation of the region for a period of four years. As part of this project, a fourth station, in Chilean Patagonia, will continue to be operated using Washington University equipment. The funding of this project will enable continued collaboration between Washington University and the Universidad de Chile in the operation of these stations, and the data will be forwarded to the IRIS data center as well as to other international seismological collaborators. Mutual data exchanges with other national groups with Antarctic seismology research programs will provide access to broadband data from a variety of other proprietary broadband stations in the region. The data will be used to study the seismicity and upper mantle velocity structure of several complicated tectonic regions in the area, including the South Shetland subduction zone, the Bransfield backarc rift, and diffuse plate boundaries in Patagonia, Drake Passage, and along the South Scotia Ridge. In particular, the operation of these stations over a longer time period will allow a better understanding of the seismicity of the South Shetland Trench, an unusual subduction zone showing very slow subduction of young lithosphere. These seismometers will also be used to record airgun shots during a geophysical cruise in the Bransfield Strait that is being planned by the University of Texas for April, 2000. These data will provide important constraints on the crustal structure beneath the stations, and the improved structural models will enable implementation of more precise earthquake location procedures in support of a seismological understanding of the region.