气候变化领域集成服务门户(CCPortal): New paleontological evidence for complex middle Paleozoic tectonic evolution in the Appalachian western Blue Ridge

CCPortal

DOI	10.1130/B35472.1
	New paleontological evidence for complex middle Paleozoic tectonic evolution in the Appalachian western Blue Ridge
	Lupo M.E.; Tull J.F.; Repetski J.; Mueller P.A.
发表日期	2020
ISSN	167606
起始页码	2105
结束页码	2118
卷号	132 期号:2021-09-10
英文摘要	Reconstructing the tectonic evolution of the southern Appalachian metamorphic internides is hampered by the relative paucity of accurate geochronologic constraints and the apparent rarity or absence of Paleozoic cover sequences. At the orogen's greatest width, near the junction of Georgia, North Carolina, and Tennessee, the western Blue Ridge is a composite metamorphic allochthon of three major thrust sheets: (A) a basal sheet above the Great Smoky fault overlying rocks of the foreland thrust belt composed of the Lower Cambrian Chilhowee Group and underlying Sandsuck Formation of the Neoproterozoic Walden Creek Group; (B) an intermediate sheet above the Maggies Mill-Citico fault composed of the middle Paleozoic Maggies Mill Formation; and (C) the main mass of the western Blue Ridge above the Alaculsy Valley-Miller Cove fault composed of the Neoproterozoic Ocoee Supergroup, and younger overlying sequences in the Epperson and Murphy synclinoria. The age of peak deformation and metamorphism in all of these sequences has historically been assigned to the Ordovician Taconic orogeny, but recent paleontologic discoveries suggest these events are significantly younger. In addition to the middle Paleozoic fauna recently reported from the Maggies Mill Formation in the intermediate thrust sheet, Silurian-Devonian conodonts have been found in units formerly correlated with the Walden Creek Group in the Epperson synclinorium. These discoveries suggest that widespread middle Paleozoic successor basin sequences unconformably overlie the Neoproterozoic-Cambrian drift-facies of the Chilhowee Group (and equivalents) and underlying rift-facies of the Ocoee Supergroup, and require modifications to existing models for the timing of the region's stratigraphic framework and tectono-metamorphic evolution. © 2019 Geological Society of America.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/184724
作者单位	Florida State University, Department of Earth, Ocean, and Atmospheric Science, Tallahassee, FL 32306, United States; U.S. Geological Survey (Emeritus), MS 926A National Center, Reston, VA 20192, United States; University of Florida, Department of Geological Sciences, Gainesville, FL 32611, United States
推荐引用方式 GB/T 7714	Lupo M.E.,Tull J.F.,Repetski J.,et al. New paleontological evidence for complex middle Paleozoic tectonic evolution in the Appalachian western Blue Ridge[J],2020,132(2021-09-10).
APA	Lupo M.E.,Tull J.F.,Repetski J.,&Mueller P.A..(2020).New paleontological evidence for complex middle Paleozoic tectonic evolution in the Appalachian western Blue Ridge.Bulletin of the Geological Society of America,132(2021-09-10).
MLA	Lupo M.E.,et al."New paleontological evidence for complex middle Paleozoic tectonic evolution in the Appalachian western Blue Ridge".Bulletin of the Geological Society of America 132.2021-09-10(2020).