气候变化领域集成服务门户(CCPortal): Hydrothermal-sedimentary dolomite - a case from the Middle Permian in eastern Junggar Basin, China

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DOI	10.1186/s42501-020-00070-0
	Hydrothermal-sedimentary dolomite - a case from the Middle Permian in eastern Junggar Basin, China
	Zhang, Shuai; Liu, Yi-Qun; Li, Hong; Jiao, Xin; Zhou, Ding-Wu
通讯作者	Liu, YQ (通讯作者)
发表日期	2020
ISSN	2095-3836
EISSN	2524-4507
卷号	9
英文摘要	The Middle Permian Lucaogou Formation in the Jimusar Sag, eastern Junggar Basin, NW China, was deposited in a salt lake within an intracontinental rift basin with intense hydrothermal activity. Hydrothermal-sedimentary dolomite in the form of three types of dolostones, namely, analcime-feldspar dolostone (AFD), silicic dolostone (SD) and buddingtonite-albite dolostone (BAD), related to syn-sedimentary hydrothermal activity at lake bottom was discovered. The characteristics and formation mechanism of the dolomite were studied based on micron-scale petrographic and isotopic geochemical research. The syn-depositional formation of these dolostones was indicated by their rock-mineral features and syn-sedimentary deformation stage. The dolomite was composed of relatively poorly ordered proto-dolomite crystals with micron-sized spherical or sub-spherical morphology and coexisted with hydrothermal minerals, including analcime, buddingtonite, albite and chalcedony. Albite clasts were replaced by the dolomite, indicating high-temperature conditions during formation. The remarkably low strontium isotopic compositions of the dolostones (Sr-87/Sr-86 with an average of 0.705687) indicated that mantle-derived materials might have involved in the ore-forming fluid. The dolostones had positive delta C-13(PDB) values (with an average of 6.94 parts per thousand) and negative delta O-18(PDB) values (with an average of -8.12 parts per thousand). Based on the delta O-18(PDB) values, the formation temperatures of the dolomite were at least similar to 25 degrees C higher than those of the penecontemporaneous dolomite in the Lucaogou Formation in the study area. It is concluded that the dolomite precipitated from hydrothermal fluid erupting at the lake bottom. The possible genetic models are described. We suggest that the hydrothermal-sedimentary dolomite is an important genetic type, and this study may help increase the awareness of this understudied type of dolomite.
关键词	LUCAOGOU FORMATION TIGHT-OIL LACUSTRINE DOLOMITE SANTANGHU BASIN JIMUSAER SAG VENT FLUIDS AMMONIUM ROCKS SYSTEMS RECORD
英文关键词	Dolomite genesis; Hydrothermal sedimentary dolomite; Permian; Lucaogou Formation; Jimusar Sag; Junggar Basin
语种	英语
WOS研究方向	Geology ; Paleontology
WOS类目	Geosciences, Multidisciplinary ; Paleontology
WOS记录号	WOS:000668736800001
来源期刊	JOURNAL OF PALAEOGEOGRAPHY-ENGLISH
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/259834
推荐引用方式 GB/T 7714	Zhang, Shuai,Liu, Yi-Qun,Li, Hong,et al. Hydrothermal-sedimentary dolomite - a case from the Middle Permian in eastern Junggar Basin, China[J]. 中国科学院青藏高原研究所,2020,9.
APA	Zhang, Shuai,Liu, Yi-Qun,Li, Hong,Jiao, Xin,&Zhou, Ding-Wu.(2020).Hydrothermal-sedimentary dolomite - a case from the Middle Permian in eastern Junggar Basin, China.JOURNAL OF PALAEOGEOGRAPHY-ENGLISH,9.
MLA	Zhang, Shuai,et al."Hydrothermal-sedimentary dolomite - a case from the Middle Permian in eastern Junggar Basin, China".JOURNAL OF PALAEOGEOGRAPHY-ENGLISH 9(2020).