Collaborative Research: Paleoseismology and Paleogeodesy of the Sumatran Subduction Zone

9903301 Sieh以前的工作已经表明，珊瑚“微环礁”提供了一个无与伦比的机会来测试地震复发的模型，因为它们记录了垂直变形通过几个大地震周期相当精确地在其形态和年度带。 在苏门答腊岛西海岸和苏门答腊俯冲带海沟之间，收集到的几块头珊瑚板记录了海平面变化引起的垂直地震间和同震变形。 在外弧脊的岛屿上，工作记录了1833年大地震期间突然出现的1-2米，在公元1608年和1380年的两次早期事件中，珊瑚上升了类似的数量，表明这种事件可能每230年发生一次。 在这些大的出现事件之间的时期，珊瑚头记录快速淹没在130公里的海沟，130和200公里的海沟之间的快速出现，和近稳定的大陆海岸，约240公里的海沟，这种模式可能是符合地震间应变积累模型。 这项建议将继续调查苏美尔俯冲带，利用珊瑚地层学、形态学和地质年代学研究1833年的巨大事件及其前身。

9903301 SiehPrevious work has demonstrated that coral "microatolls" offer an unrivalled opportunity to test models of earthquake recurrence, because they record vertical deformation through several large-earthquake cycles quite precisely in their morphology and annual banding. Between the western coast of Sumatra and the trench of the Sumatran subduction zone, several collected slabs of head corals record sea-level changes caused vertical interseismic and coseismic deformation. On the islands of the outer-arc ridge, work has documented sudden emergence of 1-2 meters during the giant earthquake of 1833, and corals uplifted similar amounts during two earlier events about AD 1608 and 1380 suggest such events might recur about every 230 years. In periods between these large emergence events, coral heads record rapid submergence within 130 km of the trench, rapid emergence between 130 and 200 km of the trench, and near-stability on the mainland coast, about 240 km from the trench, and this pattern may be consistent with interseismic strain accumulation models. This proposal will continue the investigation of the Sumatran subduction zone, studying the giant 1833 event and its predecessors using coral stratigraphy, morphology, and geochronology.