Collaborative Research: Late Wenlock-Ludlow (Silurian) Oceanic Episodes and Events, Southern Laurentia

合作研究：南劳伦西亚晚期温洛克-勒德洛（志留纪）海洋事件和事件

• 批准号: 0517976
• 负责人: James Barrick
• 金额: $ 16.61万
• 依托单位: Texas Tech University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-15 至 2009-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0517976&HistoricalAwards=false
• 关键词: Collaborative; Research; Late; Wenlock; Ludlow

Several similar models of global climate and oceanic change have been proposed since 1990 to explain lithologic, eustatic, biotic and geochemical events recorded from Silurian strata. The first, and still most prominent, of the models is that of Jeppsson, who subdivided the Silurian into a series of oceanic states separated by short-lived oceanic events, during which dramatic changes, including faunal extinctions related to drops in primary productivity, occurred. Nearly all of the detailed documentation of the models comes from the Baltic region.Testing these models requires that additional Silurian events be examined. The team will examine a span of Silurian time that includes two major events (Mulde and Lau), a minor event (Linde) and a series of shifts between oceanic episodes for which no significant 'events' have been recorded. The data will come from sections that span 3000 km across southern Laurentia, which was located distant from Baltica during the Silurian.The research will yield a reconstruction of the depositional, biotic, and geochemical history for an interval of approximately 5.0 my across the southern craton of Laurentia and extending into basins proximal to the Appalachian orogenic area. This will allow for evaluation of geographic trends in biological and geochemical factors related to water circulation from near the cratonic margin across an epeiric sea and into basins that were more or less well connected to the global ocean and were interacting with tectonic events. This will comprise the first analysis of regional expression of Silurian oceanic changes, and will also provide the detailed documentation required for in-depth comparison to sections associated with Baltica. A far better understanding of the nature of the stratigraphic record of climatic and oceanic change for the Silurian, and thereby also the Paleozoic, will result. Data will be reposited, including unprocessed samples for additional analyses (chitinozoan, palynomorphs, Sr-isotopes, etc.), and information made available for inclusion in a dynamic, interactive and time-calibrated network, such as the CHRONOS project.

自 1990 年以来，人们提出了几种类似的全球气候和海洋变化模型，以解释志留系地层记录的岩性、海平面上升、生物和地球化学事件。第一个也是最突出的模型是杰普森的模型，他将志留纪细分为一系列由短暂的海洋事件分隔的海洋状态，在此期间发生了巨大的变化，包括与初级生产力下降相关的动物灭绝。几乎所有模型的详细文档都来自波罗的海地区。测试这些模型需要检查额外的志留纪事件。该团队将研究志留纪时期的一段时间，其中包括两个主要事件（穆尔德和劳）、一个次要事件（林德）以及一系列尚未记录重大“事件”的海洋事件之间的转变。这些数据将来自劳伦西亚南部横跨 3000 公里的剖面，该地区在志留纪期间距离波罗的海很远。这项研究将重建整个南部克拉通大约 5.0 my 间隔的沉积、生物和地球化学历史。劳伦西亚并延伸到阿巴拉契亚造山区附近的盆地。这将有助于评估与水循环相关的生物和地球化学因素的地理趋势，这些水循环从克拉通边缘附近穿过远洋进入或多或少与全球海洋相连并与构造事件相互作用的盆地。这将包括对志留纪海洋变化的区域表现的首次分析，还将提供与波罗的海相关部分进行深入比较所需的详细文件。我们将更好地了解志留纪乃至古生代气候和海洋变化的地层记录的性质。数据将被重新存储，包括用于额外分析的未处理样本（几丁质动物、孢粉动物、锶同位素等），以及可包含在动态、交互式和时间校准网络（例如 CHRONOS 项目）中的信息。