Tectonic signatures in carbonate platform sequences and diagenesis proximal and distal to convergent margins

碳酸盐台地层序的构造特征以及汇聚边缘近端和远端的成岩作用

• 批准号: RGPIN-2016-06170
• 负责人: Dix, George
• 金额: $ 1.75万
• 依托单位: Carleton University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=680018
• 关键词: Tectonic; signatures; carbonate; platform; sequences

The current state of knowledge about carbonate platform systems is dominated by modern and ancient examples from relatively tectonically stable geologic settings such as found along continental trailing margins; in the interior of foreland basins distant from convergent margins; and, on oceanic platforms within plate interiors. The proposed study will investigate the depositional stability, stratigraphic geometry, and diagenesis of carbonate platforms in response to local and regional tectonism. Two geologic regions allow study of tectonic signatures at different distances from convergent (subducting) plate boundaries. (1) In central Canada (SE Ontario), a Late Ordovician (450 million years) carbonate platform overlies a regional (200 km long) fault system within the underlying and shallowly buried (*Research outcomes will be of interest to the global geological community. The research will expand on the current limited knowledge about tectonic sensitivity of carbonate depositional systems, and contrasting platform architecture in proximal to distal positions from collisional plate boundaries. The study will help characterize a potential tectonic gradient of depositional instability directed into the plate interior from convergent boundaries, and address the impact of reactivation of inherited structure on stratigraphic patterns in younger sedimentary systems. Dispersal of results will be through geological conferences and peer-reviewed journals (national, international). There will be community-level interest in the Ontario-based project because the ancient fault system underlies many rural and urban communities, and lies adjacent to the active Western Quebec Seismic Zone. Such proximity underscores potential fault reactivation as a modern, not just ancient, geological consequence.**

目前对碳酸盐台地系统的了解主要是来自构造相对稳定的地质环境（例如沿大陆尾缘发现的）的现代和古代实例；远离汇聚边缘的前陆盆地内部；并且，在板块内部的海洋平台上。拟议的研究将调查碳酸盐台地的沉积稳定性、地层几何形状和成岩作用，以响应当地和区域的构造运动。两个地质区域允许研究距会聚（俯冲）板块边界不同距离的构造特征。 (1) 在加拿大中部（安大略省东南部），一个晚奥陶世（4.5 亿年）碳酸盐台地覆盖在底层和浅埋层内的区域性（200 公里长）断层系统上（*研究成果将引起全球地质界的兴趣）该研究将扩展目前关于碳酸盐沉积系统的构造敏感性的有限知识，并对比碰撞板块边界的近端和远端位置的平台结构。该研究将有助于表征沉积不稳定性的潜在构造梯度。从聚合边界进入板块内部，并解决继承结构的重新激活对较年轻沉积系统地层模式的影响将通过地质会议和同行评审期刊（国家、国际）进行传播。人们对安大略省的项目很感兴趣，因为古老的断层系统位于许多农村和城市社区的下方，并且毗邻活跃的魁北克西部地震带。这种接近性强调了潜在的断层重新激活是一种现代而不仅仅是古代的地质后果。 **