Sector collapse kinematics and tsunami implications (SEKT)

地段坍塌是一种影响世界上大多数火山岛的地质过程。这些坍塌会产生极大的山体滑坡和相关的海啸，危及沿海社区和海底设施。该项目的主要目的是更深入地了解不同坍塌参数(体积、震源位置、运输距离)和就位过程(时间、运动学和动力学)之间的相互作用，以便更好地确定海啸级别，从而更好地评估海啸危险。在流星巡航M154期间在蒙特塞拉特火山岛近海收集的新数据构成了这个项目的基础。PIS KH和SK以及共同申请者CB是M154探险队的共同支持者。在这次考察中，绘制了蒙特塞拉特近海最新的山体滑坡--沉积1和2--的地图。特别是，矿床2具有很大的科学价值，因为它似乎由两个部分(矿床2a和2b)组成，由横向扩展的地震反射层隔开。此外，2号矿床的侵位似乎引发了海底沉积物的大规模破坏。更好地了解2号矿床的运动学和侵位过程已经是IODP 340分支的目标，它沿着1号和2号矿床的滑块钻了4个点。不幸的是，2号矿床本身的岩心恢复可以忽略不计，特别是在从2a矿床到2b矿床的过渡阶段，因此，许多研究问题仍未得到解答。本建议所基于的新的M154数据，特别是3D P电缆地震和额外的2D地震测线，与旧测线相比质量显著提高，以及使用重力取心和MeBo70钻探的长沉积物岩芯和全面的测井数据，使人们能够更好地了解坍塌运动学和侵位过程，这提供了一个独特的机会，将滑坡和海啸模型参数化，以此作为更好的海啸危险评估的关键。对于这项工作，我们在此提出两个博士项目，根据使用的方法，这两个项目将相辅相成。一名博士候选人(A)将主要从事三维P电缆和二维地震的处理和解释以及岩心-测井-地震数据的综合。第二个PHD(B)将侧重于重力岩心和MeBo70岩心，特别是它们的沉积学、岩土工程和成分分析。虽然岩心分析将提供个别岩心位置的详细信息(例如地层年龄、沉积物成分、物源面积、变形程度、运移距离和起始点等)，但钻孔测井和地震数据用于在整个区域内插补这些信息。通过这种多学科方法，我们将全面了解蒙特塞拉特的火山历史，以及侧面坍塌和相关滑坡事件及其就位过程之间的相互作用。

Sector collapses are a geological processes that affect most volcanic islands worldwide. These collapses can generate extremely large landslides and associated tsunamis, endangering coastal communities and seafloor installations. Major aim of this project is to gain deeper insight into the interplay between different collapse parameters (volume, source location, transport distance) and emplacement processes (timing, kinematics and dynamics) to enable a better determination of the tsunami magnitude and hence a better tsunami hazard assessment. New data collected during the Meteor cruise M154 offshore the volcanic island of Montserrat form the base of this project. The PIs KH and SK and the co-applicant CB were co-proponents of the expedition M154. During this expedition, the most recent landslides offshore Montserrat - Deposits 1 & 2 - were mapped. Particularly Deposit 2 is of great scientific interest as it seems to comprise two parts (Deposits 2a and 2b) separated by laterally extensive seismic reflectors. Furthermore, the emplacement of Deposit 2 seems to have triggered large-scale failure of sea floor sediment. A better understanding of the kinematics and the emplacement process of Deposit 2 has already been the aim of the IODP Leg 340 which drilled four sites along the slid masses of Deposits 1 and 2. Unfortunately, the core recovery in the slid masses of Deposit 2 itself particularly at the transition from Deposit 2a to 2b was negligible and, hence, many research questions remained unanswered. The new M154 data on which this proposal is based, especially 3D P-cable seismic and additional 2D seismic lines with significantly improved quality compared to older lines, and long sediment cores and comprehensive logging data utilizing gravity coring and MeBo70 drilling enable a better understanding of the collapse kinematics and the emplacement processes which provides a unique opportunity to parameterize landslide and tsunami models as key to a better tsunami hazard assessment. For this work we propose here two PhD projects which will complement each other according to the methods used. One PhD candidate (A) will mainly work on processing and interpretation of the 3D P-cable and 2D seismic as well as on core-log-seismic integration of the data. The second PhD (B) will focus on the gravity cores and the MeBo70 cores, in particular their sedimentological, geotechnical and compositional analyses. While core analyses will provide detailed information at individual core locations (e.g. stratigraphic ages, sediment composition, source area, degree of deformation, transport distance and initiation etc.), borehole logging and seismic data are used to interpolate these over the entire region. Through this multi-disciplinary approach, we will derive a comprehensive picture of the volcanic history of Montserrat as well as the interplay between flank collapses and associated landslide events and their emplacement processes.