Temporal velocity variations in the northern Hikurangi margin and the relation to slow slip
Temporal velocity variations in the northern Hikurangi margin and the relation to slow slip
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希库朗吉北部边缘的时间速度变化及其与慢滑移的关系
DOI：
10.1016/j.epsl.2022.117443
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发表时间：
2022
影响因子：
5.3
通讯作者：
Wallace Laura
中科院分区：
文献类型：
--
作者：
Wang Weiwei;Savage Martha K.;Yates Alexander;Zal Hubert J.;Webb Spahr;Boulton Carolyn;Warren-Smith Emily;Madley Megan;Stern Tim;Fry Bill;Mochizuki Kimihiro;Wallace Laura
过去 20 年来，人们对慢滑移事件 (SSE) 进行了越来越详细的研究，提高了我们对俯冲带过程的理解。尽管SSE与其周围物质的物理性质之间的关系仍不清楚，但新西兰北部希库朗吉边缘是相对较浅（<10公里深）且频繁的SSE的地点，为近场调查提供了极好的机会。 2014年9月至10月，发生了一次滑移超过250毫米的SSE，并被Hikurangi海底地震和慢滑移调查（HOBITSS）部署成功记录下来。本研究将散射波干涉测量法应用于九个 HOBITSS 海底地震仪 (OBS) 采集的环境噪声数据，以研究与 SSE 相关的地震速度变化。单站跨分量相关性是在我们研究区域的上板块的周期带内计算的。在 SSE 期间，平均速度变化显示出大约 0.05% 的下降，随后又出现类似幅度的增加。我们建议两种可能性。其他地震观测表明，第一种可能性是 SSE 导致板块边界上的低渗透性密封破裂。该断裂使得流体迁移到上板块中，由于上板块中的孔隙流体体积增加，导致 SSE 期间地震速度降低。在该模型下，SSE之后，上板中的流体逐渐扩散，速度再次增加。第二种可能性是速度变化与慢滑动周期期间地壳应变的变化有关，由此弹性应变在 SSE 之前积累，导致孔隙度收缩和减少，从而导致 SSE 源上方的速度增加（SSE 之间的地震速度增加）。在 SSE 过程中，随着弹性应变的释放，上板开始延伸，从而导致膨胀和孔隙率增加（地震速度降低）。 SSE 后，应力和应变再次积累，导致孔隙率降低和速度增加。
Slow slip events (SSE) have been studied in increasing detail over the last 20 years, improving our understanding of subduction zone processes. Although the relationship between SSEs and the physical properties of their surrounding materials is still not well-understood, the northern Hikurangi margin in New Zealand is the site of relatively shallow (<10 km deep), frequent SSEs, providing excellent opportunities for near-field investigations. From September to October 2014, an SSE occurred with more than 250 mm slip, and was recorded successfully by the Hikurangi Ocean Bottom Investigation of Tremor and Slow Slip (HOBITSS) deployment. This study applies scattered wave interferometry to ambient noise data acquired by nine HOBITSS ocean bottom seismometers (OBS) to study the seismic velocity variations related to the SSE. Single station cross-component correlations are computed within a period band that focuses on the upper plate in our study region. The average velocity variations display a decrease on the order of 0.05% during the SSE, followed by an increase of similar magnitude afterwards. We suggest two possibilities. The first possibility, which has been suggested by other seismological observations, is that the SSE causes a low-permeability seal on the plate boundary to break. The break allows fluid to migrate into the upper plate, causing a seismic velocity decrease during the SSE because of increased pore fluid volume in the upper plate. Under this model, after the SSE, the fluids in the upper plate diffuse gradually and the velocity increases again. The second possibility is the velocity changes are related to changes in crustal strain during the slow slip cycle, whereby elastic strain accumulates prior to the SSE, causing contraction and reduction of porosity and therefore increase of velocity above the SSE source (the seismic velocity increases between SSEs). During the SSE the upper plate goes into extension as the elastic strain is released, which results in dilation and a porosity increase (seismic velocity reduction). After the SSE, stress and strain accumulate again, causing a porosity decrease and a velocity increase.
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新西兰北岛吉斯伯恩地区新生代地质（1:50 000 公制表 Y18AB）
DOI：
10.1080/00288306.1992.9514545
发表时间：
1992
期刊：
影响因子：
--
作者：
G. Neef;R. Bottrill
通讯作者：
R. Bottrill
新西兰希库朗吉北部边缘的地震活动以及与浅层慢滑事件的潜在时空关系的调查
DOI：
10.1029/2018jb017211
发表时间：
2019
期刊：
Journal of Geophysical Research: Solid Earth
影响因子：
--
作者：
J. Yarce;A. Sheehan;J. Nakai;Susan Y. Schwartz;K. Mochizuki;M. Savage;L. Wallace;S. Henrys;S. Webb;Yoshihiro Ito;R. Abercrombie;B. Fry;H. R. Shaddox;E. Todd
通讯作者：
E. Todd
环境噪音
DOI：
10.1097/01.hj.0000554357.99563.e9
发表时间：
2019
期刊：
The Hearing Journal®
影响因子：
--
作者：
Daniel Fink
通讯作者：
Daniel Fink
影响因子：
2.8
作者：
Clarke, D.;Zaccarelli, L.;Brenguier, F.
通讯作者：
Brenguier, F.
慢滑移区域地震各向异性和 V/V 比的时空变化
影响因子：
5.3
作者：
H. Zal;K. Jacobs;M. Savage;J. Yarce;S. Mroczek;Kenny M. Graham;E. Todd;J. Nakai;Y. Iwasaki;A. Sheehan;K. Mochizuki;L. Wallace;S. Schwartz;S. Webb;S. Henrys
通讯作者：
S. Henrys