Ordovician-Silurian graptolites, integrated stratigraphy, biodiversity history, and paleoenvironmental change

奥陶纪-志留纪笔石、综合地层学、生物多样性历史和古环境变化

• 批准号: RGPIN-2018-05397
• 负责人: Melchin, Michael
• 金额: $ 2.62万
• 依托单位: St. Francis Xavier University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=659508
• 关键词: Ordovician; Silurian; graptolites; integrated; stratigraphy; Ordovician; Silurian; graptolites; integrated; stratigraphy

** p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px 'Times New Roman'}**** p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px 'Times New Roman'}******* p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px 'Times New Roman'}******* p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px 'Times New Roman'}******* * 0* 0* 1* 382* 2179* STFX* 18* 5* 2556* 14.0* * * * *** * Normal* 0* * * * * false* false* false* * EN-CA* X-NONE* X-NONE* * * * * * * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *** **** /* Style Definitions */*table.MsoNormalTable* {mso-style-name:"Table Normal";* mso-tstyle-rowband-size:0;* mso-tstyle-colband-size:0;* mso-style-noshow:yes;* mso-style-priority:99;* mso-style-parent:"";* mso-padding-alt:0cm 5.4pt 0cm 5.4pt;* mso-para-margin:0cm;* mso-para-margin-bottom:.0001pt;* mso-pagination:widow-orphan;* font-size:10.0pt;* font-family:"Times New Roman";}*******The Ordovician and Silurian periods (ca. 500-420 million years ago) were*times of dramatically changing climate, sea level, and biodiversity. One of the*biggest mass extinction events in Earth history occurred near the end of the*Ordovician Period. The most important group of animals preserved in the marine*plankton during these time periods was the graptolites, a group of mostly*extinct hemichordates. They were abundant, geographically widespread and*evolved rapidly, which makes them excellent fossils for identifying short*intervals of geologic time and correlation of those intervals around the globe.*A thorough understanding of these organisms and their distribution in*sedimentary strata maximizes our potential to use them to solve a wide range of*Earth science problems in areas such as tectonics, sedimentary basin history,*climate change, and long-term evolution of the world's oceans. My research*program has several major and ongoing objectives: 1) reconstruction of the*evolutionary history of graptolites; 2) understanding the history of change of*graptolite biodiversity as a result of changing rates of species origination*and extinction, particularly through the cycles of climatic and oceanic changes*that characterized the Ordovician and Silurian periods; and 3) studying the*physical and chemical record preserved in rock strata to better understand the*environmental cycles and their causes, particularly to gain insights into the*factors responsible for the Late Ordovician Mass Extinction. For the last objective,*I am particularly interested in the history of anoxia in the oceans – times*when large areas of the ocean became depleted in oxygen. I propose to examine*oceanic anoxia using sedimentary, paleontological and geochemical signals, and*investigate the formation and changing distribution of anoxia in terms of its*relationship to changes in climate, ocean circulation and biological*productivity. I will also integrate data from graptolite occurrences with the*geochemical record in sedimentary strata from several different parts of the*world to improve the precision with which we can define and subdivide*geological time. By improving the precision with which we can resolve*geological time, we can gain clearer insights into the timing and rates of*evolutionary, paleoenvironmental and geological processes. This research into*the long-term links among climate change, ocean circulation and biodiversity*will provide insights that will help us better understand the modern world of*changing climate and biodiversity.*** ** p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px

** p.p1 {保证金：0.0px 0.0px 0.0px 0.0px 0.0px;字体：12.0px'Times New Roman'} **** P.P1 {Margin：0.0px 0.0px 0.0px 0.0px 0.0px;字体：12.0px'Times New Roman'} **** P.P1 {Margin：0.0px 0.0px 0.0px 0.0px 0.0px; font: 14.0px 'Times New Roman'}******* * 0* 0* 1* 382* 2179* STFX* 18* 5* 2556* 14.0* * * * *** * Normal* 0* * * * * false* false* false* * EN-CA* X-NONE* X-NONE* * * * * * * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * {MSO风格的名称：“ table normal”;* MSO-TSTYLE-ROWBAND-SIZE：0;* MSO-TSTYLE-COLBAND-SIZE：0;* MSO-style-noshow：YES;* MSO-Style-Prority：99;* MSO-style-Parent-Parent-Parent-parent-parent-parent-parent-parent-parent-parent-parent-parent：“ MSO-PARA-MARGIN：0CM;*MSO-PARA-MARGIN-BOTTOM：.0001PT;*MSO-PAGINATION：WIDOW-ORPHAN;*FONT-SIZE：10.0PT;*FONT-FONT;*FONT-FONT-FONT-FONT;*TIMES NEW ROMAN;} ************************************************************************************************************************************************ 500-420万年前）*气候，海平面和生物多样性发生了巨大变化。地球历史上*最大的质量扩展事件之一发生在*奥陶纪时期结束时。在这段时间内，保存在海洋*浮游生物中的最重要的动物是Graptolites，这是一组灭绝的半缩合物。它们是丰富的，地理广泛的，并且经过迅速发展，这使它们成为识别全球各个间隔的短期*间隔和纠正的绝佳化石。世界海洋。我的研究*计划有几个主要且持续的目标：1）重建石墨进化史； 2）理解*Graptolite生物多样性变化的历史，这是由于物种起源的变化*和扩展的变化，尤其是通过气候和海洋变化的周期*，其特征是奥多维克和志留纪时期的特征； 3）研究保存在岩层中的*物理化学记录，以更好地了解*环境周期及其原因，尤其是为了了解导致晚期奥托维奇大批量灭绝的因素的见解。为了实现最后的目标，*我对海洋中的缺氧史特别感兴趣 - 时代*当海洋的大片地区耗尽氧气时。我建议使用沉积，古生物学和地球化学信号检查*海洋缺氧，并*研究缺氧与气候变化，海洋循环和生物学*生产力的关系的形成和变化。我还将将来自图形托特尔的出现的数据与来自*世界的几个不同部分的沉积层中的地球化学记录集成在一起，以提高我们可以定义和细分地质时间的精确度。通过提高我们可以解决地质时间的精确度，我们可以更清楚地了解*进化，古环境和地质过程的时间和速率。这项对气候变化，海洋循环和生物多样性之间的长期联系的研究将提供见解，以帮助我们更好地了解现代世界*改变气候和生物多样性。字体：12.0px