The role of currents for carbonate platform drowning

洋流对碳酸盐台地淹没的作用

• 批准号: 198293166
• 负责人: Professor Dr. Christian Betzler
• 金额: --
• 依托单位: Leitstelle Deutsche Forschungsschiffe
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/198293166?language=en
• 关键词: role; currents; carbonate; platform; drowning

The goal of this project is to test the hypothesis that the physical impact of currents is a major, previously underestimated or even disregarded controlling factor of tropical carbonate platform evolution, and that currents are a major contributor to carbonate platform drowning. It is proposed that strong and reversing currents inhibit progradation of shallow-water rubble and sands in the bank interior and therefore suppresses lateral expansion of shallow water facies. Two atolls of the Maldives archipelago, subjected to a complex regime of seasonally reversing monsoon currents, will be taken as a natural laboratory to provide data for model validation. It is thus proposed to compile a sedimentological and stratigraphical model contrasting with the established models of carbonate platforms developing in the trade-wind belts. This will be achieved by a combined approach of sidescan sonar and high-resolution seismic surveys as well as geological sampling. Dedicated transects through the lagoons will allow for establishing a stratigraphy, assessing the occurrence and the degree of lowstand karstification of the atoll interior, and mapping bedforms as an indicator of bottom currents. The new data will produce a snapshot of a carbonate platform caught in the drowning act, thus considerably expanding our knowledge about this process.

该项目的目的是检验以下假设：电流的物理影响是热带碳酸盐平台演化的主要估计，甚至忽略的控制因子，并且电流是导致碳酸盐平台溺水的主要原因。有人提出，强烈而逆转的水流抑制了河岸内部浅水碎石和沙子的前列，因此抑制了浅水相的横向膨胀。马尔代夫群岛的两个环环将受到季节性逆转季风电流的复杂状态，将被视为自然实验室，以提供模型验证的数据。因此，提议编译一种与贸易风带中开发的碳酸盐平台模型相反的沉积学和地层模型。这将通过侧扫声纳和高分辨率地震调查以及地质采样的联合方法来实现。通过泻湖的专用横切将允许建立地层学，评估环礁内部的低位凸孔的发生和程度，并将床形映射为底电流的指标。这些新数据将产生捕获在《溺水法案》中的碳酸盐平台的快照，从而大大扩展了我们对此过程的了解。