The biotic and sedimentologic evolution of the Cambrian

寒武纪的生物和沉积演化

• 批准号: RGPIN-2016-03914
• 负责人: Pratt, Brian
• 金额: $ 2.11万
• 依托单位: University of Saskatchewan
• 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=708576
• 关键词: biotic; sedimentologic; evolution; Cambrian

The `Cambrian Explosion' half a billion years ago was a turning point for life on Earth: the evolutionary appearance of animals in the sea, which gave rise to fossils of shells, spicules, skeletons, even sometimes soft tissues, plus new kinds of microbes and algae. This new and complex biota caused profound ecological revolution in the marine realm. Sediment changed fundamentally due to processes of burrowing, digestion, excretion, organic binding and bacterial decay. The first metazoan reefs appeared. My group will continue to investigate these phenomena in an interdisciplinary way, by combining sedimentological and paleontological approaches in order to explore more fully this exciting yet still mysterious episode of Earth History. The natural laboratory for us will be the spectacular southern Rocky Mountains. The indoor laboratory includes a wide range of analytical techniques from optical microscopy to elemental mapping using synchrotron X-ray fluorescence. The origin and evolution of ancient sediments and organo-sedimentary processes in various tropical carbonate reef, sand shoal, tidal flat, shelf and lagoonal environments will be studied from the preceding latest Precambrian through early Paleozoic time via sedimentary features, paleoecological attributes and geochemical data. In a short span of time-just some 50 million years-these successive carbonate platforms show dramatic contrasts yet also remarkable similarities. We will reconsider long-held facies interpretations and assumptions, and develop criteria to differentiate tsunami- versus storm-generated beds, and earthquake cracking from desiccation. The stratigraphic occurrence of fossils will permit high-resolution temporal correlation of lithological units and will help reveal patterns of diversification, extinction, phylogeny and times of regional and global change captured in these rocks. This wide-ranging and interdisciplinary dataset will allow us to interpret Cambrian paleoclimate, paleoceanography, sea level and sedimentation, as well as elucidate the tectonic history of the vast continental shelves and inland seas in which these rocks accumulated.

五十亿年前的“寒武纪爆炸”是地球上生命的转折点：海洋中动物的进化外观，这引起了贝壳，spicules，spicules，骨骼，甚至有时甚至有时软组织的化石，以及新型的微生物和藻类。这种新的复杂的生物群在海洋领域引起了深刻的生态革命。由于挖掘，消化，排泄，有机结合和细菌衰减的过程，沉积物从根本上发生了变化。出现了第一批后生礁。我的小组将通过结合沉积和古生物学方法来继续以跨学科的方式调查这些现象，以便更充分地探索这个令人兴奋但仍然神秘的地球历史情节。对我们来说，天然实验室将是壮观的南部落基山脉。室内实验室包括使用Synchrotron X射线荧光从光学显微镜到元素映射的广泛分析技术。在各种热带碳酸盐礁，沙滩，潮汐平坦，架子和泻湖环境中，古老的沉积物和有机物过程的起源和进化将从先前的最新前寒武纪通过早期古生代时间通过沉积物，古生物学属性和地球化学数据来研究。在短短的时间范围内 - 约5000万年 - 这些连续的碳酸盐平台表现出巨大的对比，但也出色地相似。我们将重新考虑长期控制的相位解释和假设，并制定标准以区分海啸与风暴生成的床，以及与干燥的地震破裂。化石的地层发生将允许岩性单元的高分辨率时间相关性，并有助于揭示这些岩石中捕获的多样化，消光，系统发育以及区域和全球变化的时代的模式。这个广泛的跨学科数据集将使我们能够解释寒武纪古气候，古海洋学，海平面和沉积，并阐明这些岩石积累的广阔大陆货架和内陆海洋的构造历史。