Petrofacies and Detrital Geochronologic Evolution of the Lower Pennsylvanian Pottsville Sequences from the Black Warrior and Cahaba Basins, Alabama

这次地质调查将产生关于阿拉巴马州和密西西比州北部波茨维尔地层沉积物组成和来源的关键新数据，以记录阿巴拉契亚山脉和瓦希托山脉带的起源和历史。以往的研究表明，黑勇士盆地和卡哈巴盆地上古生界的Pottsville沉积物部分来源于Ouachitas。然而，我们的初步工作表明，波茨维尔沉积物的主要来源是阿巴拉契亚山脉的三次造山活动。研究区域包括阿拉巴马州的大部分地区，奥本大学正在那里开展外展活动。这项研究旨在促进一些大学、K-12学校、国家机构和私营公司之间的科学交流和研究活动。该地区的许多化石燃料资源（煤、天然气、煤层气）都是在本研究的目标沉积物中发现的，这可能会引起公众对激动人心的科学的极大兴趣。主要研究人员将寻求扩大研究生和本科生的经验，包括女性和男性，目标是让少数民族富裕的阿拉巴马州李县和梅肯县的积极参与。该项目的结果可能会对全球山带侵蚀和邻近沉积盆地沉积模式的发展作出重大贡献。Black Warrior盆地和Cahaba盆地是北美东部晚古生代重要的碎屑楔块沉积中心，对包括Appalachian和Ouachita山带在内的构造史具有重要意义。对这些造山带沉积楔的大剖面进行了钻探，边缘隆起暴露出适合详细物源研究的地层序列，包括砂岩岩石学、重矿物分析、矿物化学和40Ar/39Ar单晶白云母年龄测定。在几个方面，喜马拉雅-阿萨姆-孟加拉的沉积体系为北美东部古生代的阿巴拉契亚-瓦奇塔-黑勇士和卡哈巴体系提供了一个有趣的现代类比。我们利用尖端技术研究喜马拉雅前陆盆地新生代碎屑楔块，建立了造山带沉积、盆地沉降、沉积中心移动和沉积物搬运路径的模型。在此，我们建议将基于新生代碎屑体系的剥蚀和沉积模型应用于古生代造山分散库。这项研究涉及阿拉巴马州和密西西比州的黑勇士和卡哈巴盆地的碎屑地质年代学和详细的沉积物组成，很有可能在阿巴拉契亚山脉南部发现曾经存在的源地体。该研究还具有为北美东部上古生界提供一个新的大地汇聚、碎屑扩散网络、盆地配置、油气潜力和构造地貌等构造情景的潜力。

This geological investigation will produce critical new data on sediment composition and provenance of the Pottsville formation in northern Alabama and Mississippi in order to document the origin and history of the Appalachian and Ouachita mountain belts. Previous studies suggest that the upper Paleozoic Pottsville sediments of the Black Warrior and Cahaba basins were derived partly from the Ouachitas. Our preliminary work, however, suggests primary derivation of Pottsville sediment from all three mountain building events of the Appalachians. The study region encompasses large segments of Alabama where Auburn University has ongoing outreach activities. This study seeks to promote scientific exchange and research activities between a number of colleges, K-12 schools, state agencies, and private companies. Many of the fossil fuel resources in this region (coal, natural gas, coalbed methane) are found in the sediments targeted in this study, potentially engendering considerable public interest in exciting science. The principal investigators will seek to broaden the experiences of graduate and undergraduate students, both female and male, with a goal of having active participation from minority-rich Lee and Macon counties of Alabama. Results from this project may contribute significantly to the development of a global model of erosion from mountain belts and deposition in adjacent sedimentary basins. The Black Warrior and Cahaba basins are important late Paleozoic depocenters of clastic wedges in eastern North America, and they potentially hold critical information on tectonic history, including that of the Appalachian and the Ouachita mountain belts. Large sections of these orogenic sedimentary wedges have been drilled, and marginal uplifts expose stratigraphic sequences appropriate for detailed provenance studies, including sandstone petrography, heavy mineral analysis, mineral chemistry, and 40Ar/39Ar single-crystal muscovite age dates. In several ways, the Himalayan-Assam-Bengal depositional system provides an intriguing modern analog for the Paleozoic Appalachian-Ouachita-Black Warrior and Cahaba system of eastern North America. Our work with cutting-edge techniques on Cenozoic clastic wedges from the foreland basins of the Himalayas has helped us develop a model for orogenic sedimentation, basin subsidence, depocenter shifting and sediment transport paths. Here we propose to apply our model of denudation and sedimentation based on a Cenozoic detrital system to a Paleozoic orogenic dispersal repository. This study involving detrital geochronology and detailed sediment composition of the Black Warrior and Cahaba basins of Alabama and Mississippi has a high probability of new discovery of source terranes that once existed in the southern Appalachians. This study also has the high potential of providing a new tectonic scenario of terrane convergence, clastic dispersal network, basinal configuration, petroleum potential, and tectonic geomorphology for the upper Paleozoic of eastern North America.