【摘要】：天津薊縣東水廠錳方硼石礦床是世界上唯一一個(gè)具有經(jīng)濟(jì)開(kāi)發(fā)價(jià)值的錳方硼石礦床,錳方硼石賦存與中元古代高于莊組二段泥晶白云巖中。本文通過(guò)微量元素分析探討了錳方硼石的成礦環(huán)境,測(cè)定結(jié)果顯示Sr/Ba=0.125~0.128;V/(Ni+V)=0.230~0.320;Th/U=4.356~4.898;V/Cr=0.018~0.026,各微量元素對(duì)比值范圍變化不大;LREE總量為66.12×10~(-6)~67.90×10~(-6),HREE總量(包含Y)為18.88×10~(-6)~19.56×10~(-6),LREE/HREE值為3.38~3.60,Y/Ho值介于28.25~29.14之間,δCe介于0.829~0.854之間,顯示為弱的負(fù)Ce異常,δEu值介于0.831~0.846之間,顯示為弱的負(fù)Eu異常。地球化學(xué)數(shù)據(jù)指示其成礦環(huán)境屬海相沉積環(huán)境,海水環(huán)境為相對(duì)氧化的狀態(tài),成礦過(guò)程中有陸源物質(zhì)的加入。Sm/Nd-Eu/Sm圖解表明研究區(qū)與柴達(dá)木盆地第三系蒸發(fā)巖較為相似,反應(yīng)錳方硼石成礦時(shí)具有類似的蒸發(fā)成因。通過(guò)對(duì)硼同位素(δ~(11)B的數(shù)值范圍為1.4‰~10.7‰)的解譯進(jìn)一步探討了錳方硼石在原生成礦階段的具體成因(海相蒸發(fā)沉積)。結(jié)合前人所做的錳方硼石地球化學(xué)數(shù)據(jù),對(duì)東水廠錳方硼石礦床的成因做出了新的解釋,即錳方硼石成礦時(shí)應(yīng)屬海相蒸發(fā)成因,而熱液活動(dòng)的過(guò)程則可能是發(fā)生于錳方硼石成礦之后,屬后期熱液改造作用,從而形成了錳方硼石復(fù)雜的地球化學(xué)特征。
[Abstract]:The Dongshuichang Manganese square borite deposit in Jixian County, Tianjin, is the only manganese square borite deposit with economic development value in the world. The manganese square borite occurs in the middle Proterozoic mudstone dolomite of the second member of the Gaogaozhuang formation. In this paper, the metallogenetic environment of manganese borite has been studied by trace element analysis. The results show that Sr/Ba=0.125~0.128;V/ (Ni V) = 0.230? 0.320? Thu? U? 4.356? 4.898. the ore-forming environment of manganite has been studied. There was no significant change in the ratio range of each trace element in the range of 0.018 and 0.026 V _ (2) Cr ~ (2 +). The total amount of LREE is 66.12 脳 10 ~ (- 6) ~ 67.90 脳 10 ~ (- 6), HREE (including Y) is 18.88 脳 10 ~ (- 6) ~ 19.56 脳 10 ~ (- 6), the LREE/ HREE value is 3.38 脳 10 ~ (- 6), the Y / Ho value is between 28.25 脳 10 ~ (- 14) and 28.25 脳 10 ~ (- 6). 未 Ce is between 0.829 and 0.854, showing weak negative Ce anomaly and 未 EU value between 0.831 and 0.846, showing weak negative Eu anomaly. Geochemical data indicate that the metallogenic environment is marine sedimentary environment and the seawater environment is relatively oxidized. The Sm / Nd-Eu/Sm diagram shows that the study area is more similar to the Tertiary evaporates in Qaidam Basin, and the reaction manganese borite mineralization has a similar evaporation origin. Based on the interpretation of the boron isotope (未 ~ (11) B in the range of 1.4 鈥，

本文編號(hào)：2446205