Dascher-Cousineau Kélian, Bürgmann Roland
Department of Earth and Planetary Science,University of California, Berkeley, Berkeley, CA, USA.
Miller Institute for Basic Science, Berkeley, CA, USA.
Sci Adv. 2024 Aug 30;10(35):eado2191. doi: 10.1126/sciadv.ado2191.
Three decades of geodetic monitoring have established slow slip events (SSEs) as a common mode of fault slip, sometimes linked with earthquake swarms and in a few cases escalating to major seismic events. However, the connection between SSEs and earthquake hazard has been difficult to quantify and contextualize beyond regional studies. We aggregate a geodetic record of SSEs from subduction zones in the circum-Pacific region. In aggregate, earthquake rates increase up to threefold concurrent with and proximal to SSEs. The relative amplitude of this increase is correlated with the SSE size and, to a lesser extent, their depth and region. The subdued and coincident earthquake response to SSE stress transfer suggests a more limited role of static stress transfer and a very short relaxation timescale for the triggered seismicity. The observed range of behavior does not support a major connection between SSEs and earthquake hazard.
三十年的大地测量监测已将慢滑移事件(SSEs)确立为一种常见的断层滑移模式,有时与地震群有关,在少数情况下会升级为重大地震事件。然而,除了区域研究之外,SSEs与地震灾害之间的联系一直难以量化和背景化。我们汇总了环太平洋地区俯冲带SSEs的大地测量记录。总体而言,地震发生率在SSEs发生期间及附近会增加两倍之多。这种增加的相对幅度与SSEs的规模相关,在较小程度上也与它们的深度和区域相关。对SSEs应力转移的地震响应较为平缓且同时发生,这表明静态应力转移的作用较为有限,且触发地震活动的弛豫时间尺度非常短。观测到的行为范围并不支持SSEs与地震灾害之间存在重大联系。