气候变化领域集成服务门户(CCPortal): Ultramafic Rock Carbonation: Constraints From Listvenite Core BT1B, Oman Drilling Project

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DOI	10.1029/2019JB019060
	Ultramafic Rock Carbonation: Constraints From Listvenite Core BT1B, Oman Drilling Project
	Beinlich A.; Plümper O.; Boter E.; Müller I.A.; Kourim F.; Ziegler M.; Harigane Y.; Lafay R.; Kelemen P.B.
发表日期	2020
ISSN	21699313
卷号	125 期号:6
英文摘要	The occurrence of the quartz-carbonate alteration assemblage (listvenite) in ophiolites indicates that ultramafic rock represents an effective sink for dissolved CO2. However, the majority of earlier studies of ultramafic rock carbonation had to rely on the surface exposure of reaction textures and field relationships. Here we present the first observations on ultramafic rock alteration obtained from the 300 m deep BT1B drill hole, ICDP Oman Drilling Project, allowing for a continuous and high-resolution investigation. Hole BT1B recovered continuous drill core intersecting surface alluvium, 200 m of altered ultramafic rock comprising mainly listvenite and minor serpentinite bands at 90 and 180 m depth, and 100 m of the underlying metamorphic sole. Textural evidence suggests that the carbonation of fully serpentinized harzburgite commenced by non-equilibrium growth of spheroidal carbonate characterized by sectorial zoning resulting from radially oriented low-angle boundaries. In the serpentinite, carbonate spheroids are composed of alternating magnesite cores and dolomite rims, whereas texturally similar carbonate in the listvenite is composed of Fe-rich magnesite cores and Ca-Fe-rich magnesite rims. The distinct compositions and mineral inclusions indicate that the carbonation extent was controlled by fluid accessibility resulting in the simultaneous formation of limited carbonate in the serpentinite bands and complete carbonation in the listvenite parts of BT1B. The presence of euhedral magnesite overgrowing spheroidal carbonate in the listvenite suggests near-equilibrium conditions during the final stage of carbonation. The carbonate clumped isotope thermometry constrains carbonate crystallization between 50 °C and 250 °C, implying repeated infiltration of reactive fluids during ophiolite uplift and cooling. ©2020. The Authors.
英文关键词	carbonation; clumped isotope; fluid–rock interaction; Listvenite; mineral replacement; Samail ophiolite
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187832
作者单位	Department of Earth Science, University of Bergen, Bergen, Norway; Department of Earth Sciences, Utrecht University, Utrecht, Netherlands; Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan; Institute of Geology and Geoinformation, Geological Survey of Japan, The National Institute of Advanced Industrial Science and Technology, Ibaraki, Japan; Géosciences Montpellier, Université Montpellier, Montpellier, France; Lamont–Doherty Earth Observatory, Columbia University, Palisades, NY, United States
推荐引用方式 GB/T 7714	Beinlich A.,Plümper O.,Boter E.,et al. Ultramafic Rock Carbonation: Constraints From Listvenite Core BT1B, Oman Drilling Project[J],2020,125(6).
APA	Beinlich A..,Plümper O..,Boter E..,Müller I.A..,Kourim F..,...&Kelemen P.B..(2020).Ultramafic Rock Carbonation: Constraints From Listvenite Core BT1B, Oman Drilling Project.Journal of Geophysical Research: Solid Earth,125(6).
MLA	Beinlich A.,et al."Ultramafic Rock Carbonation: Constraints From Listvenite Core BT1B, Oman Drilling Project".Journal of Geophysical Research: Solid Earth 125.6(2020).