Astronomical tuning and magnetostratigraphy of the Upper Triassic Xujiahe Formation of South China and Newark Supergroup Of North America: Implications for the Late Triassic time scale

doi:10.1016/j.epsl.2017.07.015

	Astronomical tuning and magnetostratigraphy of the Upper Triassic Xujiahe Formation of South China and Newark Supergroup Of North America: Implications for the Late Triassic time scale
	Li, MS; Zhang, Y; Huang, CJ; Ogg, J; Hinnov, L; Wang, YD (王永栋); Zou, ZY; Li, LQ (李丽琴)
	2017
发表期刊	Earth and Planetary Science Letters
ISSN	0012-821X
卷号	475 页码:207-223
摘要	The time scale of the Late Triassic Epoch has a divergence of age models, especially for the durations of competing definitions for its Rhaetian Stage (uppermost Triassic). The astrochronology derived from relative depth of lacustrine-bearing clastic successions and astronomically tuned geomagnetic polarity time scale (APTS) of the Newark Supergroup of eastern North America provides a basis for the Late Triassic time scale. However, the Newark APTS has been challenged regarding its age scale and completeness; therefore an independent astronomical-tuned magnetic polarity zonation is required to verify the upper Newark APTS reference scale. We compiled a 6.5 million year (myr) APTS with magnetic stratigraphy from four sections of the lacustrine-fluvial, dinosaur-track-bearing Xujiahe Formation in the Sichuan Basin of South China that also has dating from detrital zircons and regional biostratigraphy. Variations in natural gamma-ray and magnetic susceptibility that reflect variable continental weathering in the source regions of the Xujiahe Formation are paced by Milankovitch cycles, especially the 100-kyr short eccentricity and 405-kyr long eccentricity. The cycle-tuned magnetostratigraphy of the Xujiahe Formation is compared directly via the magnetic-polarity zones to the depth ranks of the Newark Supergroup that are indicative of relative depths of lacustrine facies. The Sichuan APTS indicates that there is no significant hiatus between the sedimentary succession and the basalt flows at the top of the Newark Supergroup. The Sichuan APTS is compatible with the magnetostratigraphy from the candidate Global Boundary Stratotype Section and Point (GSSP) for the Norian-Rhaetian boundary interval at the Pignola-Abriola of South Italy, but does not extend downward to the proposed GSSP in Austria associated with the longer Rhaetian option. The earliest dinosaur tracks in China are from the middle of this Xujiahe Formation, therefore are implied to be middle Rhaetian in age. This Sichuan APTS helps to resolve the controversy about the completeness and reliability of the Newark-APTS, and can be used in the future to verify if isotopic excursions in organic carbon recorded in the Italian sections that are proposed as possible secondary markers for a base-Rhaetian definition are global in nature. (C) 2017 Elsevier B.V. All rights reserved.
关键词	Late Triassic time scale magnetostratigraphy cyclostratigraphy Newark Supergroup Sichuan Basin South China
DOI	10.1016/j.epsl.2017.07.015
收录类别	SCI
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000411167800019
出版者	ELSEVIER SCIENCE BV
文献类型	期刊论文
条目标识符	http://ir.nigpas.ac.cn/handle/332004/13303
专题	中国科学院南京地质古生物研究所中国科学院南京地质古生物研究所其他
通讯作者	Huang, CJ
推荐引用方式 GB/T 7714	Li, MS,Zhang, Y,Huang, CJ,et al. Astronomical tuning and magnetostratigraphy of the Upper Triassic Xujiahe Formation of South China and Newark Supergroup Of North America: Implications for the Late Triassic time scale[J]. Earth and Planetary Science Letters,2017,475:207-223.
APA	Li, MS.,Zhang, Y.,Huang, CJ.,Ogg, J.,Hinnov, L.,...&Li, LQ .(2017).Astronomical tuning and magnetostratigraphy of the Upper Triassic Xujiahe Formation of South China and Newark Supergroup Of North America: Implications for the Late Triassic time scale.Earth and Planetary Science Letters,475,207-223.
MLA	Li, MS,et al."Astronomical tuning and magnetostratigraphy of the Upper Triassic Xujiahe Formation of South China and Newark Supergroup Of North America: Implications for the Late Triassic time scale".Earth and Planetary Science Letters 475(2017):207-223.