干旱区生态环境知识资源中心(Arid): Facies analysis, petrography and geochemistry of the Neogene gypsum deposits in the Eshtehard area, Alborz Province, Iran

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DOI	10.22059/GEOPE.2019.291757.648510
	Facies analysis, petrography and geochemistry of the Neogene gypsum deposits in the Eshtehard area, Alborz Province, Iran
	Zaheri, Masoomeh; Rafiei, Behrouz
通讯作者	Rafiei, B (corresponding author), Bu Ali Sina Univ, Coll Sci, Dept Geol, Hamadan, Hamadan, Iran.
来源期刊	GEOPERSIA
ISSN	2228-7817
出版年	2020
卷号	10 期号:2 页码:289-303
英文摘要	The evaporite deposits examined in this study are located in the Eshtehard area (SW of the Alborz Province). Four outcrop sections (Mard Abad, Eshtehard, Salt Mine and Rud Shur) and thirty gypsum samples were selected for facies analysis, petrographical and mineralogical investigation in combination with the geochemical analyses. The Neogene evaporites are composed of massive, selenite, nodular and satin-spar gypsum lithofacies. Three different textures were recognized under microscope: porphyroblastic, alabastrine, and fibrous gypsum. Petrographical investigations and X-ray diffraction analysis showed the evaporite beds are mainly composed of gypsum, with no anhydrite relics. The characteristics of these litho- and microfacies indicate gypsum deposited in the lacustrine and sabkha settings. The ICP-OES analysis shows significant differences in major and trace element contents of the four types of gypsums. The concentrations of Sr, Fe, Al, Mg and Na were increased in massive gypsum, while the crystals represent a decreased in size. The contents of these elements were also decreased in nodular, fibrous and selenite gypsums. These are probably indicating an increase and decrease in brine concentration, respectively. Paleoclimate condition is simply determined for the Neogene evaporites using geochemical approach. The results suggest a shift from semi-arid (bottom) to arid (top) paleoclimate conditions.
英文关键词	Gypsum Texture Lacustrine Environment Strontium Neogene Deposits Eshtehard Alborz Province
类型	Article
语种	英语
收录类别	ESCI
WOS记录号	WOS:000598748600005
WOS关键词	CALCIUM-SULFATE DIHYDRATE ; WESTERN QAIDAM BASIN ; PARTITION-COEFFICIENTS ; LACUSTRINE SEDIMENTS ; THAR DESERT ; EVAPORITE ; MIOCENE ; GROWTH ; LAKE ; RECONSTRUCTION
WOS类目	Geosciences, Multidisciplinary
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/352589
作者单位	[Zaheri, Masoomeh; Rafiei, Behrouz] Bu Ali Sina Univ, Coll Sci, Dept Geol, Hamadan, Hamadan, Iran
推荐引用方式 GB/T 7714	Zaheri, Masoomeh,Rafiei, Behrouz. Facies analysis, petrography and geochemistry of the Neogene gypsum deposits in the Eshtehard area, Alborz Province, Iran[J],2020,10(2):289-303.
APA	Zaheri, Masoomeh,&Rafiei, Behrouz.(2020).Facies analysis, petrography and geochemistry of the Neogene gypsum deposits in the Eshtehard area, Alborz Province, Iran.GEOPERSIA,10(2),289-303.
MLA	Zaheri, Masoomeh,et al."Facies analysis, petrography and geochemistry of the Neogene gypsum deposits in the Eshtehard area, Alborz Province, Iran".GEOPERSIA 10.2(2020):289-303.