Global Seismograph Network Improvements

[9319923]赫特地球的深层内部仍然是一个重要的科学前沿，它掌握着理解地球起源的关键，它在地质时期演变到现在的结构，以及板块动力学、地震、火山活动和地磁场的内部原因。在几公里以下（钻探和侵蚀暴露的极限）无法直接观察的地壳、地幔和地核主要是通过它们与地震波的相互作用来研究的。地震传感器设计、数字数据采集、传输和存储技术的最新发展使地震成像方法的分辨率有了显著提高。地震学联合研究机构，或IRIS联盟，由85所美国大学组成，在地震学方面有研究和教学项目。它作为发展、部署和支持现代数字地震仪器的国家设施，其任务分为三个主要项目要素：(1)全球地震台网（GSN）计划为美国提供了一个由128个永久的、标准化的、极宽带（VBB）的、宽动态范围的数字地震台站组成的国际网络，这些台站在全球大约2000公里的距离上。(2)大陆岩石圈阵列地震研究项目（PASSCAL）旨在建立美国国家600台便携式地震仪系统资源，可用于特定区域地震成像实验的现场部署和地震研究的快速反应。(3) IRIS数据管理系统（DMS）旨在为国内和国际地震研究界提供及时访问GSN和pascal计划数据的能力。它对来自这些程序的数据进行归档和分发，并促进数据的标准化和交换。迄今为止，IRIS联盟完成了以下具体任务：(1)为GSN开发了采用VBB传感器技术的标准化永久站仪器IRIS-1和IRIS-2系列。GSN的两个IRIS操作和维护设施分别安装在美国地质调查局的阿尔伯克基地震实验室和加州大学圣地亚哥分校。目前，全球已安装了48个GSN VBB站，并正在返回数据。(2) pascal计划开发了两个仪器中心，用于存储、维修和部署其标准化的便携式地震仪器包。帕斯卡尔仪器池现在有超过200个单位的库存，安置在帕斯卡尔仪器中心位于帕利塞兹的拉蒙特-多尔蒂地球天文台，纽约和斯坦福大学，加利福尼亚。pascal仪器已用于大量计划中的现场实验，并迅速用于亚美尼亚（1987年）、洛马·普里塔（1989年）和兰德斯/大熊（1992年）大地震的余震研究。(3) DMS在阿尔伯克基地震实验室和加州大学圣地亚哥分校建立了GSN数据收集节点。目前在华盛顿州西雅图安装了一个由华盛顿大学管理的IRIS中央数据存档和分发中心。通过互联网，美国用户（欧洲用户通过荷兰的ORFEUS数据中心）可以访问大多数现有GSN站的连续数据流，近实时的大事件波形数据，以及重要地震的特殊数据集，以及PASSCAL现场实验。该奖项为参与美国地质调查局阿尔伯克基地震实验室建立IRIS全球地震台网和相关数据管理活动提供了1993财年资金。＊＊＊

9319923 Hutt The Earth's deep interior remains a major scientific frontier that holds the key to understanding the origin of the planet, its evolution through geologic time to the present structure, and the internal causes of plate dynamics, earthquakes, volcanism, and the geomagnetic field. Inaccessible to direct observation below a few kilometers (the limit of drilling and exposure by erosion) the Earth's crust, mantle, and core are primarily studied through their interaction with seismic waves. Recent developments in seismic sensor design, digital data acquisition, transmission, and storage techniques make possible dramatic improvements in the resolving power of seismic imaging methods. The Incorporated Research Institutions for Seismology, or the IRIS Consortium, is composed of 85 U.S. universities with research and teaching programs in seismology. It serves as a national facility for the development, deployment, and support of modern digital seismic instrumentation, and its mission is organized into three major program elements: (1) The Global Seismographic Network (GSN) program provides the U.S. contribution to an international network of 128 permanent, standardized, very-broad-band (VBB), wide dynamic range digital seismic stations at a spacing of approximately 2000 km around the globe. (2) The Program for Array Seismic Studies of the Continental Lithosphere (PASSCAL) aims to establish a U.S. national resource of 600 portable seismometer systems available for field deployment in specific regional seismic imaging experiments and for rapid response to earthquake studies. (3) The IRIS Data Management System (DMS) aims to provide the national and international seismic research community with timely access to data from the GSN and PASSCAL programs. It archives and distributes the data from these programs and facilitates the standardization and exchange of data. The IRIS Consortium so far has accomplished the following speci fic tasks: (1) It developed the IRIS-1 and IRIS-2 lines of standardized permanent station instrumentation employing VBB sensor technology for the GSN. Two IRIS operations and maintenance facilities for the GSN were installed at the U.S. Geological Survey's Albuquerque Seismological Laboratory and at the University of California, San Diego. Currently, 48 GSN VBB stations have been installed world- wide and are returning data. (2) The PASSCAL program has developed two instrument centers to store, repair, and deploy its standardized portable seismographic instrument packages. The PASSCAL instrument pool now has an inventory of over 200 units housed at PASSCAL instrument centers located at Lamont-Doherty Earth Observatory in Palisades, New York and at Stanford University, California. PASSCAL instruments have been used in a large number of planned field experiments, and were also rapidly deployed for aftershock studies of the Armenia (1987), Loma Prieta (1989), and Landers/Big Bear (1992) major earthquakes. (3) The DMS has established GSN data collection nodes at the Albuquerque Seismological Laboratory and at the University of California, San Diego. An IRIS central data archive and distribution center is now installed in Seattle, Washington, operated by the University of Washington. Through Internet, U.S. users (and European users via the ORFEUS data center in the Netherlands) have access to the continuous data streams from most of the existing GSN stations, to major-event waveform data in near-real time, and to special datasets from important earthquakes, as well as from PASSCAL field experiments. This award provides FY-1993 funding for the participation of the U.S. Geological Survey's Albuquerque Seismological Laboratory in establishing the IRIS Global Seismographic Network and for related data management activities. ***