RUI: Integrated Stratigraphic and Sedimentological Analysis of the Cambro-Ordovican Inner Shelf, Colorado

RUI：科罗拉多州寒武纪-奥陶纪内陆架综合地层学和沉积学分析

• 批准号: 9419141
• 负责人: Paul Myrow
• 金额: $ 9.08万
• 依托单位: Colorado College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-02-15 至 1998-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9419141&HistoricalAwards=false
• 关键词: RUI; Integrated; Stratigraphic; Sedimentological; Analysis

9419141 Myrow The relationship between intervals of faunal turnover, including major extinctions, and various depositional and tectonic processes which may ultimately govern these events, is critical to the holistic understanding of the stratigraphic record. Integration of sedimentological, paleontological, and stratigraphic data from all regions in an onshore-offshore profile are required for a complete analysis of system dynamics. The Cambro-Ordovician boundary interval, which records several faunal turnover events including a major extinction at the base of the Cordylodus proavis conodont zone, is generally unrecognized or not preserved in inner detrital belt deposits in North America because of poor biostratigraphic resolution. Sedimentological and biostratigraphic data from well-documented Cambro-Ordovician platform and offshore areas of the Great Basin and elsewhere have been used to propose processes-response models for faunal extinctions, which in many cases include puported ecstatic "events". Unfortunately, little or no information exists from coeval proximal carnal deposits concerning the relationship of intervals of faunal turnover with depositional and tectonic events, which can be used as a test of the cause of extinctions or the global correlation of proposed ecstatic events. Well-exposed and thick Cambro-Ordovician siliciclastic and carbonate carnal rocks in central and western Colorado provide an excellent opportunity to assess spatial and temporal changes in depositional systems during and between faunal turnover events for this poorly understood and biostratigraphically unconstrained paleogeographic region in the Cambro-Ordovician of ancient North America. A two-year project is proposed for a sedimentological and stratigraphic study in which the recognition of unconformitites using conodont biostratigraphy and sedimentological criteria will for the first time enable construction of a detailed sequence-stratigraphic framework for the Cambro-Ordovician of Colorado. Co mparison of systems dynamics for these deposits with well-documented outboard successions will contribute to a more complete understanding of the interplay between the evolution of faunal communities and depositional systems.

9419141 Myrow 动物区系更替的间隔（包括主要灭绝）与可能最终控制这些事件的各种沉积和构造过程之间的关系对于全面理解地层记录至关重要。 要对系统动力学进行完整的分析，需要将陆上-海上剖面中所有区域的沉积学、古生物学和地层数据进行整合。 寒武纪-奥陶纪边界区间记录了几次动物区系更替事件，包括 Cordylodus proavis 牙形刺带底部的一次重大灭绝，但由于生物地层分辨率较差，该边界区间通常未被识别或未保存在北美内部碎屑带沉积物中。 来自有据可查的寒武纪-奥陶纪平台和大盆地近海地区及其他地方的沉积学和生物地层数据已被用来提出动物群灭绝的过程-响应模型，其中在许多情况下包括所谓的欣喜若狂的“事件”。 不幸的是，关于动物群更替间隔与沉积和构造事件之间关系的同时代近端肉质沉积物中存在很少或根本没有信息，这些信息可以用来测试灭绝原因或拟议的狂喜事件的全球相关性。 科罗拉多州中部和西部暴露良好且厚的寒武纪-奥陶纪硅质碎屑岩和碳酸盐岩为评估古代北美寒武纪-奥陶纪这个人们知之甚少且生物地层学不受限制的古地理区域动物更替事件期间和之间沉积系统的时空变化提供了极好的机会。 提出了一个为期两年的沉积学和地层研究项目，其中使用牙形刺生物地层学和沉积学标准识别不整合岩将首次能够为科罗拉多州寒武纪-奥陶纪构建详细的层序地层框架。将这些沉积物的系统动力学与有据可查的外侧演替进行比较将有助于更全面地了解动物群落演化和沉积系统之间的相互作用。