Three-Dimensional Seismic Reflection Investigation of Fluid Flow and Structural Evolution: Northern Barbados Ridge

深海沟的楔形增生生长机制是板块构造学的一个基本问题。虽然存在预测海底形状的模型，但关于变形结构的几何形状、沉积的强度或控制下冲断层底部的剪切阻力的信息很少。流体在沉积带的沉积增积、变形、成岩作用和变质作用中起着至关重要的作用，但对流体途径和脱水时间的研究才刚刚开始。流体在控制岩石强度和抗剪性方面的重要性已被认识到，但很少有数据研究这些特性的空间或时间。本项目将对巴巴多斯近海初始剥落、底沉积和变形带的增生棱镜进行高分辨率三维地震反射测量。目的是表征结构几何形状，并确定吸积棱镜前部的流体路径。地震数据将受到大量其他地球物理数据以及该地区以前海洋钻探结果的限制。该项目的结果将用于规划在巴巴多斯的更多钻探。

The mechanics of accretionary wedge growth along deep sea trenches is a fundamental problem in plate tectonics. Although models exist which predict seafloor shape, sparse information exists on the geometry of deformation structures, strength of the accreting sediments, or shear resistance along the base of the fault zone which controls underthrusting. It is well recognized that fluids play a crucial role in sediment accretion, deformation, diagenesis, and metamorphism in accretionary zones, but study of fluid pathways and timing of dewatering have just begun. The importance of fluids in controlling the strength of rocks and shear resistance is recognized, but little data exists to investigate these properties spatially or temporally. The present project will conduct a high-resolution three- dimensional seismic reflection survey of the accretionary prism offshore Barbados in the zone of initial off-scraping, underplating and deformation of sediments. The objectives are to characterize the structural geometries, and identify fluid pathways in the frontal part of the accretionary prism. The seismic data will be constrained by an extensive suite of other geophysical data, as well as the results of previous ocean drilling in the region. Results from this project will be used in planning additional drilling in Barbados.