Collaborative Research: Late Paleozoic-Mesozoic Fauna, Environment, Climate and Basinal History: Beardmore Glacier Area, Transantarctic Mountains

合作研究：晚古生代-中生代动物群、环境、气候和盆地历史：比尔德莫尔冰川地区、横贯南极山脉

• 批准号: 0126086
• 负责人: John Isbell
• 金额: $ 18.19万
• 依托单位: University of Wisconsin-Milwaukee
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0126086&HistoricalAwards=false
• 关键词: Collaborative; Research; Late; Paleozoic; Mesozoic

This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a study to investigate paleoenvironmental conditions during the late Paleozoic and Mesozoic in central interior Antarctica. The 4 km thick sequence of sedimentary rocks, known as the Beacon Supergroup, in the Beardmore Glacier area records 90 million years of Permian through Jurassic history of this high-paleolatitude sector of Gondwana. It accumulated in a foreland basin with a rate of subsidence approximately equal to the rate of deposition. The deposits have yielded diverse vertebrate fossils, in situ fossil forests, and exceptionally well preserved plant fossils. They give a unique glimpse of glacial, lake, and stream/river environments and ecosystems and preserve an unparalleled record of the depositional, paleoclimatic, and tectonic history of the area. The excellent work done to date provides a solid base of information on which to build understanding of conditions and processes.This project is a collaborative study of this stratigraphic section that will integrate sedimentologic, paleontologic, and ichnologic observations to answer focused questions, including: (1) What are the stratigraphic architecture and alluvial facies of Upper Permian to Jurassic rocks in the Beardmore area?; (2) In what tectonostratigraphic setting were these rocks deposited?; (3) Did vertebrates inhabit the cold, near-polar, Permian floodplains, as indicated by vertebrate burrows, and can these burrows be used to identify, for the first time, the presence of small early mammals in Mesozoic deposits?; and (4) How did bottom-dwelling animals in lakes and streams use substrate ecospace, how did ecospace use at these high paleolatitudes differ from ecospace use in equivalent environments at low paleolatitudes, and what does burrow distribution reveal about seasonality of river flow and thus about paleoclimate? Answers to these questions will (1) clarify the paleoclimatic, basinal, and tectonic history of this part of Gondwana, (2) elucidate the colonization of near-polar ecosystems by vertebrates, (3) provide new information on the environmental and paleolatitudinal distributions of early mammals, and (4) allow semi-quantitative assessment of the activity and abundance of bottom-dwelling animals in different freshwater environments at high and low latitudes. In summary, this project will contribute significantly to an understanding of paleobiology and paleoecology at a high latitude floodplain setting during a time in Earth history when the climate was much different than today.

该奖项由极地方案办公室南极地质和地球物理方案提供，为研究南极内陆中部晚古生代和中生代的古环境条件提供资金。Beardmore冰川地区4公里厚的沉积岩序列被称为Beacon Supergroup，记录了冈瓦纳这一高古纬度地区从二叠纪到侏罗纪的9000万年历史。它聚集在一个前陆盆地中，沉降速率近似等于沉积速率。这些矿床产出了各种脊椎动物化石、原地化石森林和保存异常完好的植物化石。它们提供了冰川，湖泊和溪流/河流环境和生态系统的独特一瞥，并保存了该地区沉积，古气候和构造历史的无与伦比的记录。迄今为止所做的出色工作提供了一个坚实的信息基础，在此基础上建立对条件和过程的理解。该项目是对该地层剖面的合作研究，将综合沉积学、古生物学和遗迹学观察，以回答重点问题，包括：（1）Beardmore地区上二叠统至侏罗纪岩石的地层结构和冲积相是什么？(2)这些岩石是在什么构造地层环境中沉积的？(3)脊椎动物的洞穴表明，脊椎动物是否居住在寒冷的、接近极地的二叠纪泛滥平原上？这些洞穴能否首次用来识别中生代沉积物中早期小型哺乳动物的存在？（4）湖泊和溪流中的底栖动物是如何利用基底生态空间的，在这些高古纬度的生态空间利用与在低古纬度的同等环境中的生态空间利用有何不同，洞穴分布揭示了河流流量的季节性和古气候的什么？这些问题的答案将（1）阐明古气候，盆地，和构造历史的冈瓦纳这一部分，（2）阐明殖民近极地生态系统的脊椎动物，（3）提供新的信息的环境和古纬度分布的早期哺乳动物，和（4）允许半定量评估的活动和丰富的底部-栖息在高纬度和低纬度不同淡水环境中的动物。总之，该项目将大大有助于了解古生物学和古生态学在高纬度洪泛平原设置在地球历史上的时间，当气候与今天大不相同。