Seismogenic zone processes of Hikurangi subduction, New Zealand: illumination using the SAHKE seismic project

新西兰 Hikurangi 俯冲带的地震带过程：使用 SAHKE 地震项目进行照明

• 批准号: 1061557
• 负责人: David Okaya
• 金额: $ 37.96万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2015-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1061557&HistoricalAwards=false
• 关键词: Seismogenic; zone; processes; Hikurangi; subduction

Great earthquakes and tsunamis occur at subduction zones such as Sumatra, Japan, Peru-Chile, and Cascadia. The first three localities have been sites of recent events, while the third is expected to produce a great earthquake along the northwest coast of the U.S. at some time in the furture. The Hikurangi subduction system off North Island, New Zealand exhibits a range of slip conditions, from aseismic to strongly coupled, with strain release by coseismic, slow slip, and repeating microseismic events, but it has not been the site of a great M8+ earthquake, either because conditions here do not support such an event, or, more likely, because no large event has occurred since Europeans arrived there in the mid 19th century. Consequently, understanding seismicity in the Hikurangi subduction system is a matter of considerable societal relevance. Multi-disciplinary studies reveal the complex interplay between upper and lower plate structure, subducting sediment, thermal effects, regional tectonic stress regime, and fluid pressures to control the presence and distribution of the Hikurangi seismogenic zones. This study comprises a comprehensive seismological study of the southern Hikurangi system with the aim of characterizing its strongly coupled seismogenic zone and its downdip transition into an aseismic slow slip regime. In additional to its obvious societal relvance, the broader impacts of this study include cross-natioanl trianig of graduate students from the U.S., New Zealand and Japan, and a research experience for undergraduates.

大地震和海啸发生在苏门答腊、日本、秘鲁-智利和卡斯卡迪亚等俯冲带。前三个地点是最近发生地震的地点，而第三个地点预计将在未来某个时候在美国西北海岸沿着发生大地震。新西兰北岛外的Hikurangi俯冲系统表现出一系列的滑动条件，从无震到强耦合，通过同震，缓慢滑动和重复的微震事件释放应变，但它不是M8+大地震的地点，因为这里的条件不支持这样的事件，或者，更有可能的是，因为自从欧洲人在世纪中期到达那里以来，还没有发生过什么大事件。因此，了解希库朗吉俯冲系统的地震活动性是一个相当大的社会相关性问题。多学科研究揭示了上、下板块结构、俯冲沉积、热效应、区域构造应力状态和流体压力之间复杂的相互作用，从而控制了希库朗吉孕震带的存在和分布。这项研究包括对南部Hikurangi系统进行全面的地震学研究，目的是描述其强耦合孕震区及其向地震慢滑区的下倾过渡。除了明显的社会相关性外，这项研究的更广泛影响包括来自美国的研究生的跨国trianig，新西兰和日本，并为本科生的研究经验。