RAPID: Astrochronology of the Middle to Late Devonian platform margin strata from the Canning Basin, Australia and implications for timing of Middle-Late Devonian events

快速：澳大利亚坎宁盆地中-晚泥盆世台地边缘层的天文年代学及其对中-晚泥盆世事件时间的意义摘要澳大利亚西北部坎宁盆地礁群中-晚泥盆世地层记录了许多岩性旋回和跨越吉韦阶/弗拉斯阶边界的造礁动物和无脊椎动物的大规模灭绝。该提案旨在开发一个地球化学代理集组成的13 Corg和生物标志物脂质从两个地点沿着与有机丰富的相，以评估这种大规模灭绝的时间和持续时间。本研究的目的有三：1。根据现代天文学理论，评估Menyous Gap和Pillara采石场内的详细Milankovitchian特征，并讨论珊瑚灭绝事件的时间结果：这种灭绝是长期的还是相对突然的？2.重建海洋生产力（13 Corg）和陆地生态系统条件（叶蜡衍生的正构烷烃）的古环境变化。使用13 Corg和正构烷烃中的长期趋势和低频轨道周期，在盆地内和其他地方的类似年龄地层中产生更好的相关性。这项研究是紧迫的，因为有限的时间内，现有的更大的坎宁项目，结合磁性地层学，牙形石生物地层学，牙形石锶同位素年代地层学，生物标志物分析，调查中晚泥盆世古环境和生物变化。收集这些数据增加了一个新的层面（旋回地层学）的范围之外，但补充现有的坎宁项目。

RAPID: Astrochronology of the Middle to Late Devonian platform marginstrata from the Canning Basin, Australia and implications for timingof Middle-Late Devonian eventsJessica WhitesideBrown UniversityEAR-0956563ABSTRACTMiddle-Late Devonian age strata in the Canning Basin reef complex, northwestern Australia, record numerous lithological cycles and an extensive extinction among reef formers and invertebrates across the Givetian/ Frasnian boundary. This proposal seeks to develop a geochemical proxy set consisting of 13Corg and biomarker lipids from two locales along the Lennard Shelf with organic rich-facies to assess the timing and duration of this mass extinction. The goals of this research are three-fold:1. Assess the detailed Milankovitchian characters of Menyous Gap and within the Pillara Quarry with respect to modern astronomical theory and to discuss the results with respect to timing of the coral extinction events: Was this extinction protracted or relatively sudden?2. Reconstruct paleoenvironmental change in marine productivity (13Corg) and terrestrial ecosystem conditions (leaf wax-derived n-alkanes).3. Produce better correlation both within the basin and to similarly aged strata elsewhere using secular trends and low-frequency orbital cycles in 13Corg and n-alkanes. This research is urgent because of the limited time left within the existing larger Canning Project that combines magnetostratigraphy, conodont biostratigraphy, conodont Sr isotope chronostratigraphy, and biomarker analysis to investigate Middle-Late Devonian paleoenvironmental and biotic change. Gathering these data adds a new dimension (cyclostratigraphy) outside the scope of, but complementary to the existing Canning Project.