Provenance of Nicobar Fan sediments from IODP Expedition 362, offshore Sumatra

俯冲带，一个板块被压在另一个板块之下，是最大规模地震的地点，通常与造成自然灾害的海啸的产生有关。这类海啸地震是由所谓的“孕震带”中沿俯冲板块上部的滑动事件引起的。进入板块及其沉积物盖层的物质性质(“俯冲输入”)很可能与来自不同沉积物来源或来源的沉积物类型随时间的变化有关(本研究建议的重点)，在海啸地震的产生中起着关键作用。沉积物类型及其在三个维度上的堆积方式(称为“岩石地层学”)对俯冲带的物质性质和构造行为产生一级影响2。岩土工程师和地质学家认为，粗粒和细粒深海沉积物的三维位置和比例会影响俯冲输入的摩擦系数和渗透率。这项拟议的研究将通过聚焦于进入俯冲区的厚厚的沉积桩3，大大有助于更好地了解这些问题，并提供与IODP远征322次远征(日本近海的一名船上科学家)的对比研究，后者调查了通过俯冲向前缘所谓的南开吸积棱柱及其下方输送的输入物质。

Subduction zones, where one plate is forced beneath another, are the locations of the largest-magnitude earthquakes, often associated with the generation of tsunamis that pose a natural hazard. Such tsunamigenic earthquakes are caused by slip events along the upper part of the subducting plate in the so-called "seismogenic zone". The material properties of the incoming plate and its sediment cover ("subduction inputs"), likely linked to changing sediment types over time from different sediment sources or provenances (the focus of this research proposal), play a critical role inthe generation of tsunamigenic earthquakes. The sediment types and the way in which they are stacked in three dimensions (called "lithostratigraphy") exerts a first-order influence over the material properties and tectonic behaviour of subduction zones2. The 3D location and proportion of coarse- versus fine-grained deep-marine sediments are appreciated among geotechnical engineers and geologists to affect coefficients of friction and permeability of the subduction inputs. This proposed research will contribute significantly to an improved understanding of these problems by focussing on the thick sedimentary pile entering a subduction zone3, and provide a comparative study to that of IODP Expedition 322, offshore Japan (on which the PI was a shipboard scientist), that investigated input materials transported by subduction toward and beneath the frontal so-called Nankai accretionary prism.