Seismologic and Geodetric Investigation of the M=8.2 Irian Jaya, Indonesia Earthquake of February 17, 1996

1996 年 2 月 17 日印度尼西亚伊里安查亚 8.2 级地震的地震学和大地测量

• 批准号: 9706120
• 负责人: Robert McCaffrey
• 金额: $ 6.79万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-07-15 至 1999-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9706120&HistoricalAwards=false
• 关键词: Seismologic; Geodetric; Investigation; M=8.2; Irian

9706120 McCaffrey This research is to study the February 17, 1996, M=8.2 earthquake along the northwestern coast of Irian Jaya. It is among the largest in recent times and occurred in a region considered to be relatively inactive, based on past seismicity, seismic reflection profiles in the new Guinea trench, and recent geodetic measurements. The earthquake produced wide-spread destruction of coastal communities resulting largely from a tsunami and lesser effects from strong shaking. The focal mechanism suggests that the earthquake was either caused by southward thrusting of the Pacific plate beneath the island of New Guinea or by steep rupture of the oceanic lithosphere beneath the New Guinea trench. With supplemental funding from NSF to support field work, in March of 1996 the investigators operated a portable seismic network for 3 weeks, reoccupied a GPS network, and made field estimates of coseismic subsidence from changes in high tide marks. Islands around Biak are well distributed above the quake, providing a rare opportunity to study details of a great earthquake. The first-order goal is to determine which plane ruptured during the main shock. The tectonic setting provides also an opportunity to study the dynamic interaction of parallel thrust and strike-slip faults that display slip partitioning during the earthquake sequence. This grant funds the analysis of the data collected, analysis of the main shock and larger aftershocks, and an additional occupation of the GPS network to help separate coseismic slip from the rapid interseismic slip and to compare slip late in one quake cycle to that early in the next, and to interpret the significance of this great earthquake and its aftershocks. ***

9706120麦卡弗里这次研究是为了研究1996年2月17日伊里安查亚西北海岸发生的M=8.2地震。根据过去的地震活动、新几内亚海沟的地震反射剖面和最近的大地测量，它是近年来最大的地震之一，发生在一个被认为相对不活跃的地区。地震对沿海社区造成了广泛的破坏，主要是由于海啸造成的，强烈震动的影响较小。震源机制表明，地震要么是由于太平洋板块向南冲到新几内亚岛下方，要么是由于新几内亚海沟下方大洋岩石圈的急剧破裂。1996年3月，在美国国家科学基金会的补充资金支持下，研究人员运营了一个便携式地震台网3周，重新占用了一个GPS台网，并对涨潮标志变化引起的同震下沉进行了现场估计。比亚克周围的岛屿分布在地震上方，这为研究大地震的细节提供了难得的机会。第一级目标是确定哪个平面在主震期间破裂。构造背景也为研究平行逆冲断层和走滑断层的动态相互作用提供了机会，这些断层在地震序列中表现为滑动分割。这笔赠款用于分析收集的数据，分析主震和较大余震，以及额外占用GPS网络，以帮助区分同震滑动和快速震间滑动，比较一个地震周期的晚期滑动和下一个地震周期的早期滑动，并解释这次大地震及其余震的意义。***