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

阿拉巴马州 Black Warrior 和 Cahaba 盆地宾夕法尼亚下波茨维尔层序的岩相和碎屑年代学演化

• 批准号: 0911687
• 负责人: Ashraf Uddin
• 金额: $ 29.03万
• 依托单位: Auburn University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-15 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0911687&HistoricalAwards=false
• 关键词: Petrofacies; Detrital; Geochronologic; Evolution; Lower

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.

这项地质调查将产生关于北方亚拉巴马和密西西比波茨维尔组沉积物成分和物源的重要新数据，以记录阿巴拉契亚和沃希托山带的起源和历史。先前的研究表明，黑勇士和卡哈巴盆地的上古生界波茨维尔沉积物部分来自于瓦希塔斯。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所有三次造山活动。该研究区域包括亚拉巴马的大部分地区，奥本大学正在进行推广活动。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令人兴奋的科学的极大兴趣。主要研究人员将寻求扩大研究生和本科生的经验，无论是男性还是女性，目标是有来自少数民族丰富的亚拉巴马李和梅肯县的积极参与。该项目的成果可能会大大有助于开发一个全球山区侵蚀和邻近沉积盆地沉积模型。 黑勇士和卡哈巴盆地是北美东部重要的晚古生代碎屑楔沉积中心，它们可能包含阿巴拉契亚和沃希托山带等构造历史的关键信息。 这些造山沉积楔的大部分已被钻探，边缘隆起暴露出适合详细物源研究的地层序列，包括砂岩岩相学、重矿物分析、矿物化学和40 Ar/39 Ar单晶白云母年龄测定。在几个方面，喜马拉雅-阿萨姆-孟加拉沉积体系提供了一个有趣的现代模拟的古生代阿巴拉契亚-瓦希塔-黑勇士和卡哈巴系统的北美东部。我们对喜马拉雅山前陆盆地新生代碎屑楔的尖端技术研究帮助我们建立了造山沉积、盆地沉降、沉积中心移动和沉积物搬运路径的模型。在这里，我们建议应用我们的模型的剥蚀和沉积的基础上新生代碎屑系统的古生代造山分散存储库。这项研究涉及碎屑地质年代学和详细的沉积物成分的黑战士和卡哈巴盆地的亚拉巴马和密西西比有一个新的发现源岩，曾经存在于阿巴拉契亚山脉南部的可能性很高。该研究还具有为北美东部上古生界提供一个新的构造背景，即碎屑汇聚、碎屑分散网络、盆地结构、石油潜力和构造地貌。