气候变化领域集成服务门户(CCPortal): Timing of deep-water slope evolution constrained by large-n detrital and volcanic ash zircon geochronology, Cretaceous Magallanes Basin, Chile

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DOI	10.1130/B31757.1
	Timing of deep-water slope evolution constrained by large-n detrital and volcanic ash zircon geochronology, Cretaceous Magallanes Basin, Chile
	Daniels B.G.; Auchter N.C.; Hubbard S.M.; Romans B.W.; Matthews W.A.; Stright L.
发表日期	2018
ISSN	167606
起始页码	438
结束页码	454
卷号	130 期号:2021-03-04
英文摘要	Deciphering depositional age from deposits that accumulate in deep-water slope settings can enhance understanding of shelf-margin evolutionary timing, as well as controlling mechanisms in ancient systems worldwide. Basin analysis has long employed biostratigraphy and/or tephrochronology to temporally constrain ancient environments. However, due to poor preservation of index fossils and volcanic ash beds in many deepwater systems, deducing the timing of slope evolution has proven challenging. Here, we present > 6600 new U-Pb zircon ages with stratigraphic information from an ~100-kmlong by ~2.5-km-thick outcrop belt to elucidate evolutionary timing for a Campanian-Maastrichtian slope succession in the Magallanes Basin, Chile. Results show that the succession consists of four stratigraphic intervals, which characterize four evolutionary phases of the slope system. Overall, the succession records 9.9 ± 1.4 m.y. (80.5 ± 0.3 Ma to 70.6 ± 1.5 Ma) of graded clinoform development punctuated by out-of-grade periods distinguished by enhanced coarse-grained sediment bypass downslope. Synthesis of our results with geochronologic, structural, and stratigraphic data from the basin suggests that slope evolution was largely controlled by an overall decline in basin subsidence from 82 to 74 Ma. In addition to providing insight into slope evolution, our results show that the reliability of zircon-derived depositional duration estimates for ancient sedimentary systems is controlled by: (1) the proportion of syndepositionally formed zircon in a strati-graphic interval; (2) the magnitude of the uncertainty on interval-bounding depositional ages relative to the length of time evaluated; and (3) the geologic time (i.e., period/era) over which the system was active. © 2017 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/185070
作者单位	Department of Geoscience, University of Calgary, 2500 University Drive NW, Calgary, AB T2N1N4, Canada; Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States; Department of Geosciences, Colorado State University, 1482 Campus Delivery, Fort Collins, CO 80523-1482, United States
推荐引用方式 GB/T 7714	Daniels B.G.,Auchter N.C.,Hubbard S.M.,et al. Timing of deep-water slope evolution constrained by large-n detrital and volcanic ash zircon geochronology, Cretaceous Magallanes Basin, Chile[J],2018,130(2021-03-04).
APA	Daniels B.G.,Auchter N.C.,Hubbard S.M.,Romans B.W.,Matthews W.A.,&Stright L..(2018).Timing of deep-water slope evolution constrained by large-n detrital and volcanic ash zircon geochronology, Cretaceous Magallanes Basin, Chile.Bulletin of the Geological Society of America,130(2021-03-04).
MLA	Daniels B.G.,et al."Timing of deep-water slope evolution constrained by large-n detrital and volcanic ash zircon geochronology, Cretaceous Magallanes Basin, Chile".Bulletin of the Geological Society of America 130.2021-03-04(2018).