Cyclic anoxia and organic rich carbonate sediments within a drowned carbonate platform linked to Antarctic ice volume changes: Late Oligocene-early Miocene Maldives

doi:10.1016/j.epsl.2019.05.019

	Cyclic anoxia and organic rich carbonate sediments within a drowned carbonate platform linked to Antarctic ice volume changes: Late Oligocene-early Miocene Maldives
	Swart, Peter K.1; Blattler, Clara L.2; Nakakuni, Masatoshi 3; Mackenzie, Greta J.1; Betzler, Christian 4; Eberli, Gregor P.1; Reolid, Jesus 5; Alonso-Garcia, Montserrat 6,7,29; Slagle, Angela L.8; Wright, James D.9
刊名	EARTH AND PLANETARY SCIENCE LETTERS
	2019-09
卷号	521 页码:1-13
关键词	sapropels anoxia sea level carbonate platforms
ISSN号	0012-821X
DOI	10.1016/j.epsl.2019.05.019
英文摘要	This paper reports on the newly discovered occurrence of thick sequences (similar to 100 m) of Late Oligocene and Early Miocene (similar to 24.9 to similar to 20 Ma) interbedded organic-rich sediments (sapropels) and pelagic (organic poor) carbonates at Sites 01466 and U1468 drilled in the Maldives archipelago during the International Ocean Discovery Program (IODP) Expedition 359. This occurrence is unusual in that this sequence is located > 1000 m above the surrounding ocean floor within an inter-atoll basin and not linked to any known global oceanic events. Total organic content reaches as high as 35% in the darker layers, while the interbedded carbonates have concentrations of less than 0.1%. Trace elements characteristic of anoxic waters, such as Mo, V, Cr, U, and Pb, correlate positively with concentrations of organic carbon. Nitrogen isotopic data show no evidence that the intervals of high total organic carbon are related to enhanced productivity driven by upwelling. Instead, high organic carbon is associated with intervals of anoxia. We propose that sea-level fluctuations linked to changes in Antarctic ice volume restricted exchange with the open ocean causing bottom waters of the inter-atoll basin to become anoxic periodically. The architecture of the platform at the end of the Oligocene, combined with the global sea-level highstand, set the stage for orbitally-driven sea-level changes producing cyclic deposition of sapropels. The proposed mechanism may serve as an analogue for other occurrences of organic carbon rich sediments within carbonate platform settings. (C) 2019 Elsevier B.V. All rights reserved.
资助项目	IODP U.S. Science Support Program[NSF OCE1450528]
WOS关键词	SAANICH INLET ; TRACE-METALS ; EVENTS ; SHALES ; GEOCHEMISTRY ; RESOLUTION ; PARTICLES ; EVOLUTION ; BEHAVIOR ; SINKING
WOS研究方向	Geochemistry & Geophysics
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000476963300001
内容类型	期刊论文
源URL	[http://ir.fio.com.cn:8080/handle/2SI8HI0U/24553]
专题	自然资源部第一海洋研究所
通讯作者	Swart, Peter K.
作者单位	1.Univ Miami, Dept Marine Geosci, RSMAS, Miami, FL 33149 USA 2.Univ Chicago, Dept Geophys Sci, 5734 S Ellis Ave, Chicago, IL 60637 USA 3.Soka Univ, Dept Environm Engn Symbiosis, 1-236 Tangi Cyo, Hachioji, Tokyo 1920003, Japan 4.Univ Hamburg, CEN, Inst Geol, Bundesstr 55, D-20146 Hamburg, Germany 5.Univ Granada, Dept Estratig & Paleontol, Avd Fuente Nueva S-N, E-18071 Granada, Spain 6.IPMA, Rua Alfredo Magalhaes Ramalho,6, P-1495006 Lisbon, Portugal 7.Univ Algarve, Ctr Ciencias Mar CCMAR, P-8005139 Faro, Portugal 8.Columbia Univ, Lamont Doherty Earth Observ, Borehole Bldg 61 Route 9W, Palisades, NY 10964 USA 9.Rutgers State Univ, Dept Geol Sci, 610 Taylor Rd, Piscataway, NJ 08854 USA 10.Univ Edinburgh, Grant Inst, Sch GeoSci, Kings Bldg,James Hutton Road, Edinburgh EH9 3FE, Midlothian, Scotland
推荐引用方式 GB/T 7714	Swart, Peter K.,Blattler, Clara L.,Nakakuni, Masatoshi,et al. Cyclic anoxia and organic rich carbonate sediments within a drowned carbonate platform linked to Antarctic ice volume changes: Late Oligocene-early Miocene Maldives[J]. EARTH AND PLANETARY SCIENCE LETTERS,2019,521:1-13.
APA	Swart, Peter K..,Blattler, Clara L..,Nakakuni, Masatoshi.,Mackenzie, Greta J..,Betzler, Christian.,...&Yao, Zhengquan.(2019).Cyclic anoxia and organic rich carbonate sediments within a drowned carbonate platform linked to Antarctic ice volume changes: Late Oligocene-early Miocene Maldives.EARTH AND PLANETARY SCIENCE LETTERS,521,1-13.
MLA	Swart, Peter K.,et al."Cyclic anoxia and organic rich carbonate sediments within a drowned carbonate platform linked to Antarctic ice volume changes: Late Oligocene-early Miocene Maldives".EARTH AND PLANETARY SCIENCE LETTERS 521(2019):1-13.