SeaMARK II and Seismic Reflection Study of the Southeast Bahamas-Hispaniola Collision Zone

SeaMARK II 和巴哈马东南部-伊斯帕尼奥拉碰撞带的地震反射研究

• 批准号: 8812720
• 负责人: Henry Mullins
• 金额: $ 7.04万
• 依托单位: Syracuse University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-01-15 至 1991-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8812720&HistoricalAwards=false
• 关键词: SeaMARK; II; Seismic; Reflection; Study

Accreted shallow-water carbonate terranes are a common feature of many ancient mountain belts, yet the tectonic history of the majority these terranes remains poorly understood. In many cases, this is because early deformational structures associated with initial accretion have been overprinted and obliterated by post-accretion structural and metamorphic events. In order to fully understand the mechanism(s) of these shallow- water carbonate terranes, an active collision zone involving a shallow-water carbonate bank must be studied. A detailed swath mapping and seismic reflection study of the active collision between the southeastern Bahamas and the island of Hispaniola will be used. Here, the small, isolated banks of the Bahamas are colliding obliquely with the northern margin of Hispaniola, as part of the broad, transpressional North American-Caribbean Plate boundary. The collisional setting of the southeast Bahamas contrasts markedly with the tectonically quiescent, passive-margin setting of the northwest Bahamas, providing an unparalleled opportunity to compare and contrast the development of shallow-water carbonate banks in widely differing tectonic regimes. proposed use of the SeaMARC II seafloor mapping system, in conjunction with digitally recorded single-channel seismic reflection profiles, provides a system that is ideally suited for our proposed studies, which will focus on documenting shallow structures and surficial sedimentary features within the collision zone. %%% Carbonate deposits in mountain belts are commonly associated with shallow marine sediments that have been thrust onto the continent during tectonic episodes. This project will study carbonate sediments on the Hispaniola margin as a modern analog of the type of carbonate terrains that are found in tectonically active regions. The sedimentology and structural setting will be examined using a combination of coring, seismic strtigraphy, and side-scan sonar imaging (SeaMarc II). Results may be used to interpret carbonate sediments in the many accreted terrains where such deposits are found.

增生的浅水碳酸盐岩是一个共同的特征 许多古老的山脉，但地质构造的历史， 大多数人对这些问题仍然知之甚少。在许多 这是因为早期的变形构造 与最初的吸积有关， 被增生后的构造和变质事件所湮没。 为了充分理解这些浅层的机制， 水碳酸盐岩，一个活跃的碰撞带， 必须研究浅水碳酸盐岩库。 详细的条带 活动碰撞的填图和地震反射研究 位于巴哈马东南部和伊斯帕尼奥拉岛之间 将用于 在这里，巴哈马群岛的小而孤立的银行 斜向撞击伊斯帕尼奥拉岛的北方边缘， 作为北美-加勒比海地区广阔的， 板块边界。 东南板块的碰撞背景 巴哈马群岛与构造上的平静形成鲜明对比， 巴哈马西北部的被动边缘环境，提供了一个 无与伦比的机会来比较和对比 广泛发育浅水碳酸盐岩滩 不同的地质构造 建议使用SeaMARC II 海底测绘系统，结合数字记录 单道地震反射剖面，提供了一个系统 这非常适合我们提出的研究， 重点记录浅层结构和表层 碰撞带内的沉积特征。 %%% 山区碳酸盐岩矿床通常与 这些浅海沉积物被冲到了 大陆板块的构造 该项目将研究 作为现代类似物的伊斯帕尼奥拉岛边缘的碳酸盐沉积物 这种类型的碳酸盐地形 构造活动区 沉积学和构造学 将使用取芯、地震、 地层学和侧扫声纳成像（SeaMarc II）。 结果 可以用来解释碳酸盐沉积物在许多 发现这种沉积物的加积地形。