Facies Anatomy and Early Diagenesis of Carbonate Rocks

碳酸盐岩的相解剖与早期成岩作用

• 批准号: RGPIN-2019-03994
• 负责人: James, Noel
• 金额: $ 2.19万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714540
• 关键词: Facies; Anatomy; Early; Diagenesis; Carbonate

Carbonate sedimentary rocks such as limestone are largely made of marine fossils. These components that formed in ancient marine environments tell us much about the very ancient oceans on our planet and thus the history of our world. The limestones are, furthermore, significant archives of the evolution of marine life, amongst the nation's most prolific hydrocarbon reservoirs, and critical aquifers for fresh water and so human wellbeing. The aim of the science proposed here is to ascertain how marine carbonate sediments form in the ocean today (facies anatomy) and how they are then transformed into rock (early diagenesis) throughout the vastness of geologic time. These findings are then used to decipher global climate change and to generate predictive scientific models that can be used by earth scientists to interpret ancient rocks. The focus is on the most poorly understood of these sediments and rocks, specifically cool-water and high latitude polar marine carbonates and related deposits (heterozoan carbonates), the processes of early chemical alteration both terrestrial and marine that changed them, and the perplexing origin of 1 billion year old Precambrian carbonates. Much of the planned research will take place on and adjacent to the southern Australian continental shelf, the largest area of cool-water, heterozoan, carbonate deposition in the modern world. Expanding on previous NSERC-supported research in the region, specific questions will be addressed via an integrated field program utilizing extensive onland mapping, sampling, and geochemical analysis, marine research, and computer modeling. Research will focus on shallow marine, marginal marine, and lacustrine depositional systems. Funds are also requested to investigate very ancient limestones, specifically 1) to understand how late Devonian (~380 million year old) warm-water (photozoan) reefs formed just prior to a global extinction event, and 2) to determine, via the nature of carbonate sedimentation, how the global ocean evolved during the Neoproterozoic (~800 million years ago) just before the evolution of complex animals. Highly Qualified Personnel (HQP) are an integral part of this science. Graduate and undergraduate students are involved in all aspects of the research both in the field (land and marine) and in the laboratory (petrography and geochemistry). They present their results at scientific meetings and are authors on resulting scientific papers. End users of this research are those scientists that research ancient carbonate rocks. Paleontologists, paleoceanographers, and sedimentary geologists utilize the information to unravel the rock record. Canadian geoscientists using comparative reasoning to search for and exploit hydrocarbon reservoirs and mineral deposits, together with researchers monitoring marine environmental change through time must be familiar with details of deposition and early diagenesis to be successful.

石灰石等碳酸盐沉积岩主要由海洋化石制成。 在古代海洋环境中形成的这些组成部分向我们讲述了我们星球上非常古老的海洋以及我们世界的历史。 此外，石灰石是海洋生物进化的重要档案，在美国最多产的碳氢化合物储层中，以及淡水的关键含水层以及如此人类的福祉。 这里提出的科学的目的是确定当今海洋中的碳酸盐沉积物是如何在整个地质时期变成岩石（早期成岩作用）的方式。 然后，这些发现被用来破译全球气候变化，并产生可被地球科学家使用的预测科学模型来解释古代岩石。重点是这些沉积物和岩石中最鲜为人知的，特别是凉水和高纬度的极性海洋碳酸盐和相关的沉积物（核糖碳酸盐），早期化学变化的过程都改变了它们，以及改变了它们的困扰，是10亿年历史的前寒武纪前碳酸盐。 计划中的大部分研究都将在南澳大利亚州大陆架上进行并毗邻，澳大利亚大陆架子是凉水，杂质者，碳酸盐，现代世界中最大的区域。 扩大该地区NSERC支持的研究，将通过广泛的Onland映射，采样和地球化学分析，海洋研究和计算机建模来解决特定问题。 研究将重点放在浅海，边缘海洋和湖间沉积系统上。还要求资金调查非常古老的石灰石，特别是1）了解泥盆纪（约3.8亿年历史）温暖的水（光zoan）珊瑚礁在全球灭绝事件之前形成的礁石，以及2），以确定碳酸盐沉积的性质，通过碳酸盐沉积物的性质，全球在灭绝的动物（〜8亿年前）中如何演变为全球海洋。 高素质的人员（HQP）是该科学不可或缺的一部分。研究生和本科生都参与了该领域（土地和海洋）和实验室（岩石学和地球化学）研究的各个方面。他们在科学会议上介绍了结果，并且是由此产生的科学论文的作者。 这项研究的最终用户是研究古碳酸盐岩石的科学家。古生物学家，古环摄影师和沉积地质学家利用信息来揭示岩石记录。 加拿大地球科学家使用比较推理来搜索和利用碳氢化合物储层和矿物沉积物，以及随着时间的流逝监测海洋环境变化的研究人员，必须熟悉沉积和早期成岩作用的细节，并取得成功。