Collaborative Research: Integrated Eocene-Oligocene Stratigraphy of Alabama and Mississippi Boreholes: Comparison with the NJ Transect and Global Sea-Level Proxies

[506451]全球海平面、局部构造和沉积物供应的变化过程控制被动大陆边缘沉积。要确定它们各自的作用，需要对不同构造背景下的地层剖面进行连续采样和定年。全球海平面研究是全球变化计划的一个基本组成部分，海平面研究需要在被动大陆边缘钻孔的横断面。这些样带将首先关注渐新世-近代“冰窖”，未来的钻探将解决古新世-始新世“温室”和“双屋”期间的海平面变化，当时冰量变化不明显。在美国国家科学基金会的资助下，主要研究人员目前正在开发新泽西沿海平原始新世至中新世中期序列的确定年表，但需要其他被动边缘的准确年代剖面来评估波动与局部影响的作用。先前和正在进行的研究表明，来自阿拉巴马州西部和密西西比州东部的连续岩心提供了从始新世中期到渐新世中期的新鲜、未风化的物质。主要研究人员将对最近在密西西比州钻探的三个井眼进行磁、生物和同位素（锶、氧和碳）综合研究。ARCO资助的初步结果表明，这些井眼包含扩展的始新统上至渐新统下剖面，适合进行磁同位素、生物同位素和sr同位素研究。这些部分应该与主要研究者在新泽西正在进行的研究进行比较。阿拉巴马州和密西西比州的研究将提供渐新世的“冰屋”样带，与新泽西州的序列和其他全球海平面变化的代用物进行比较，并提供始新世早期“温室”和始新世中后期“双屋”的详细样带。＊＊＊

9506451 Kent The processes of global sea-level, local tectonics, and changes in sediment supply control passive continental margin sedimentation. Determining the role of each requires continuous sampling and dating of stratigraphic sections in different tectonic settings. Global sea level studies are a fundamental component of global change programs and sea level studies require drilling transects of boreholes on passive continental margins. These transects will first focus on the Oligocene-Recent "Icehouse" with future drilling to address sea-level changes during the Paleocene- Eocene "Greenhouse" and "Doubthouse" when ice-volume changes were not apparent. The principal investigators are currently developing, with NSF funding, a firm chronology of New Jersey coastal plain Eocene to middle Miocene sequences, but require well- dated sections on other passive margins to evaluate the role of eustatic versus local effects. Previous and ongoing studies show that continuous cores from western Alabama and eastern Mississippi provide fresh, unweathered material from the middle Eocene to the "middle" Oligocene. The principal investigators will conduct integrated magneto-, bio-, and isotopic (Sr, oxygen, and carbon) studies of three recently drilled boreholes in Mississippi. Preliminary results funded by ARCO show that these boreholes contain expanded upper Eocene to lower Oligocene sections suitable for magneto-, bio-, and Sr-isotope studies. These sections should compare well with the principal investigator's ongoing studies in New Jersey. The Alabama and Mississippi studies will provide an "Icehouse" transect of the Oligocene to compare with sequences in New Jersey and other proxies of global sea-level change and a detailed transect of the "Greenhouse" early Eocene and "Doubthouse" middle-late Eocene. ***