RAPID: Collaborative Research: Off-shore coseismic effects of the Port au Prince earthquake, Haiti

在海地发生灾难性的M7级地震之后，迫切需要记录余震并收集短暂的数据，这将有助于评估该区域的短期(即时)和长期地震风险。迫切需要沿断裂带的应变积累和孕震释放的可靠模型。一个美国团队已经在地面上安装了额外的地震仪和GPS站，并安装了与地震相关的地图功能，而一个法国团队正准备在近海部署一套海底地震仪。1月12日的主震破裂了恩里基洛-芭蕉园断裂带(EPGF)的相对较小的一段，EPGF是两个平行的东西向左转构造的南部，容纳了北美和加勒比海板块之间的大部分运动。EPGF位于南部半岛的核心地带，与几次历史上的大地震有关，但其1700年前的古地震活动尚不清楚。多条NW-SE向断裂和褶皱与EPGF相交，也可能处于活动状态。其中许多结构都没有测绘，特别是近海，包括太子港的一个可能的结构。这项关于主断裂近海部分以及沿南部半岛和太子港的一些次级构造的调查将通过记录近海地震的近地表效应和描述孕震构造的特征来补充这些努力。调查将包括浅水(300米)多波束测绘、重合和定向侧扫声纳、线性调频(0.5-12千赫)声纳剖面和现场取心。这项研究的主要更广泛的影响是它非常高和直接的社会相关性。

In the aftermath of the catastrophic M7 earthquake in Haiti there is an urgent need to record aftershocks and capture ephemeral data that will help to assess both short term (immediate) and long term earthquake risk in the region. Reliable models of strain accumulation and seismogenic release along the fault zone are urgently needed. A U.S. team is already on the ground, installing additional seismometers and GPS stations and mapping features associated with the earthquake, and a French team is preparing to deploy a suite of ocean bottom seismometers offshore. The January 12 mainshock ruptured a relatively small segment of the Enriquillo-Plantain Garden fault zone (EPGF), the southern of two parallel E-W sinistral transforms accommodating most of the motion between the North America and Caribbean plates. The EPGF follows the core of the southern peninsula and is associated with several large historic earthquakes, but its pre-1700?s paleoseismicity is unknown. A number of NW-SE faults and folds intersect the EPGF and may also be active. Many of these structures are unmapped, especially offshore, including a possible one in the Baie de Port au Prince. This survey of the offshore portion of the main rupture and of some of the secondary structures associated with it along the southern peninsula and the Baie de Port au Prince will complement those efforts by documenting the near surface effects of the earthquake offshore and characterizing the seismogenic structures. The survey will include shallow water (300 m) multibeam mapping, with coincident and targeted sidescan sonar, and chirp (0.5-12 kHz) sonar profiles, and spot coring. The principal broader impact of this study is its very high and immediate societal relevance.