地质学报2016，Vol.90Issue(2)：398-408,11.
天津蓟县东水厂锰方硼石矿床成因新认识
The New Understanding of the Cause of Dongshuichang Chambersite Deposit in Jixian,Tianjin
摘要
Abstract
The chambersite deposit in Jixian,Tianjin is the only one around the world with its economic development value,it occurred in putty crystal dolomites of the second segment of Mesoproterozoic Gaoyuzhuang Formation.In view of the speciality of the deposit,this paper discussesed the metallogenic environment of chambeisite through the analysis of the trace elements.The results showed that Sr/Ba=0.125~0.1284,V/(V+Ni)=0.230 ~0.320,Th/U=4.356 ~4.898,V/Cr=0.018 ~0.026,and revealed the little change of the trace elements;the amount of LREE was 66.12 ×10 -6 ~ 67.90 × 10 -6 ,the total HREE(including Y)was 18.88×10 -6 ~19.56×10 -6 ,LREE/HREE value ranged from 3.38 to 3.60,Y/Ho=28.25~29.14,δCe was between 0.829 and 0.854,shown as a slightly Ce negative anomaly,δEu ranged from 0.831~0.846,which reflected the slightly Eu negative anomaly.Geochemical data indicated that the metallogenic environment belong to marine facies sedimentary environment,the seawater may in the state of relative oxidation,some terrigenous material added in the metallogenic process of chambeisite.The diagram of Sm/Nd-Eu/Sm show that the study area is close to the evaporite from Qaidam Basin in Tertiary,relfecting the chambersite has the similar cause .We further discussesed the specific causes (marine evaporation)of the chambersite formed in the original stage by the interpretation of the boron isotope(δ11 B ranged from 1.4 ‰ to 10.7‰).Combined with previous chambersite geochemical data,we made a new explanation about the cause of Dongshuishang chambersite deposit.The deposite should be explained as the cause of marine evaporation,while the process of hydrothermal activity may occur after the formation of chambersite,belonging to the late hydrothermal alteration,and finally resulted the complex geochemical characteristics of chambersite.关键词
锰方硼石/微量元素/硼同位素/海相蒸发/热液改造/天津蓟县Key words
chambersite/trace element/boron isotope/marine evaporation/hydrothermal alteration/Jixian,Tianjin引用本文复制引用
王富良,付勇,徐志刚,裴浩翔,江冉,周文喜..天津蓟县东水厂锰方硼石矿床成因新认识[J].地质学报,2016,90(2):398-408,11.基金项目
本文为中国地质大调查“我国重要矿产和区域成矿规律研究”（编号1212010633903）和“中国地质大调查项目中国矿产地质与区域成矿规律综合研究（中国矿产地质志）”编号（12120114039701、12120114039601）等项目资助的成果。 （）
