The Hikurangi subduction zone is capable of producing moderate to large earthquakes as well as regularly repeating slow slip events. However, it is unclear what structures host these different slip styles along the margin. Here we address whether splay faults can host seismic slip at shallow (<1 km) depth by investigating the Pāpaku fault, sampled during International Ocean Discovery Program Expedition 375. We use biomarker thermal maturity to search for evidence of frictional heating within turbiditic sediments of the Pāpaku fault. Four zones of localized high temperature are found near the top of the fault zone, which are interpreted to be zones of localized seismic slip. Thermal modeling shows that the most likely maximum displacement on the shallow Pāpaku fault during each event was 14–17 m. Our results demonstrate that the Pāpaku fault, and potentially other splay faults along the margin, host coseismic slip and have the potential to produce large tsunami (e.g., runup heights of >1 m as observed in the 1947 Poverty and Tolaga Bay earthquakes.

中文翻译：

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Hikurangi俯冲带大型张开断层地震滑动证据

Hikurangi 俯冲带能够产生中到大地震以及定期重复的慢滑动事件。然而，尚不清楚是哪些结构沿边缘承载了这些不同的滑动样式。在这里，我们通过调查在国际海洋发现计划远征 375 期间采样的 Pāpaku 断层来解决张开断层是否可以在浅（<1 公里）深度承载地震滑动。 Pāpaku 错误。在断层带顶部附近发现了四个局部高温带，它们被解释为局部地震滑动带。热模型显示，在每次事件期间，浅层 Pāpaku 断层上最可能的最大位移为 14-17 m。我们的结果表明，Pāpaku 断层，