Late Cretaceous potash evaporites in Savannakhet Basin of middle Laos: Geochemical evidences of non-marine inputs

ISL OpenIR > 青海盐湖研究所知识仓储

	Late Cretaceous potash evaporites in Savannakhet Basin of middle Laos: Geochemical evidences of non-marine inputs
	Zhang XiYing1 ; Cheng HuaiDe1 ; Tan HongBing 2; Yuan XiaoLong1 ; Li YongShou1,3 ; Miao WeiLiang1,3 ; Li TingWei 1; Ma HaiZhou1
	2015-09-01
发表期刊	ACTA PETROLOGICA SINICA
卷号	31 期号:9 页码:2783-2793
关键词	Potash Evaporite Nonmarine Input Trace Element Oxygen And Hydrogen Isotope Savannakhet Basin Of Laos Khorat Plateau
摘要	Upper Cretaceous Nongbok Formation potash evaporites in Savannakhet Basin of middle Laos are the important materials for studying the regional evolution of ore-forming brines. The contents of trace elements in salt minerals together with their change characteristics reveal that the source of these salts was from the seawater but the supply of deep-seated water was also a significant source. The study results show that the so-called "basal" anhydrite only were the residues of primary halites which were leached by the late water-rock reaction. Slightly negative delta D and delta(18) O values of hydration water and marine nature of Br in carnallites indicate that these minerals were the products evaporated from the concentrated seawater mixed with meteoric water and that the continental water exerted influence to some extent on the evolution of ore-forming brine. These evaporites in the lower section of Nongbok Formation are divided into three different evolutionary stages: (1) Stage of marine input: the seawater entered into salt basin and voluminously hakes deposited; the transgression is characterized by the early obvious fluctuation and the late stabilization; the transition of marine to nonmarine input occurred at latest stage and then continental inputs was gradually dominant for the hydrologically closed and restricted salt basin; the components of ore-forming brine were changed by input of deep-seated fluid. (2) Stage of nonmarine input and mixed brine evaporation: the potash deposits formed during progressive evaporation; a slightly freshening event of brine happened at the early stage. (3) Stage of post-depositional reworking: the buried carnallitite was translated into the sylvitite by leaching of ground water and therefore the sylvite is the secondary mineral which substituted for precursor carnallite. Systematical analyses of trace element, oxygen and hydrogen isotope show that the nonmarine inputs played an important role during the evolution of ore-forming brine post-depositional reworking.
语种	英语
引用统计
文献类型	期刊论文
条目标识符	http://ir.isl.ac.cn/handle/363002/6163
专题	青海盐湖研究所知识仓储盐湖地质与环境实验室
作者单位	1.Chinese Acad Sci, Key Lab Salt Lake Resources & Chem, Key Lab Salt Lake Geol & Environm Qinghai Prov, Qinghai Inst Salt Lakes, Xining 810008, Peoples R China 2.Hohai Univ, Sch Earth Sci & Engn, Nanjing 210098, Jiangsu, Peoples R China 3.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Zhang XiYing,Cheng HuaiDe,Tan HongBing,et al. Late Cretaceous potash evaporites in Savannakhet Basin of middle Laos: Geochemical evidences of non-marine inputs[J]. ACTA PETROLOGICA SINICA,2015,31(9):2783-2793.
APA	Zhang XiYing.,Cheng HuaiDe.,Tan HongBing.,Yuan XiaoLong.,Li YongShou.,...&Ma HaiZhou.(2015).Late Cretaceous potash evaporites in Savannakhet Basin of middle Laos: Geochemical evidences of non-marine inputs.ACTA PETROLOGICA SINICA,31(9),2783-2793.
MLA	Zhang XiYing,et al."Late Cretaceous potash evaporites in Savannakhet Basin of middle Laos: Geochemical evidences of non-marine inputs".ACTA PETROLOGICA SINICA 31.9(2015):2783-2793.