The mechanism of formation of the Lincang germanium deposit is discussed in thelight of the spatial distribution of Ge-rich coal and siliceous rocks, the sulfur isotopic composi-tion of pyrite in the Ge-rich coal, the...The mechanism of formation of the Lincang germanium deposit is discussed in thelight of the spatial distribution of Ge-rich coal and siliceous rocks, the sulfur isotopic composi-tion of pyrite in the Ge-rich coal, the variation of Ge abundance in the coal seams and the geo-chemical characteristics of the siliceous rocks. The results show that the siliceous rocks interca-lated with the coal seams were deposited from a hydrothermal medium through which germani-um was enriched in the coal beds. The primary source of germanium is thought to be the Ge-rich granite in the basement of the sedimentary basin.展开更多
The mineralization is related closely to sedimentation, diagenesis and hydrothermal processes. In this paper, investigations are carried out on coal occurrence, maceral composition, inorganic minerals, trace elements ...The mineralization is related closely to sedimentation, diagenesis and hydrothermal processes. In this paper, investigations are carried out on coal occurrence, maceral composition, inorganic minerals, trace elements and huminite reflectance. It is concluded that the source of Lincang superlarge deposit is mainly the muscovite granite in the west edge of the basin. During sedimentation, Ge (germanium) was leached out and entered the basin. Ge was adsorbed by lower organism and humic substances in water. Lincang lignite underwent three thermal processes: peatification, early diagenesis and hydrothermal transformation. During peatification, Ge was adsorbed or complexed by humic colloids. During early diagenesis, the Ge associated with humic acids was hard to mobilize or transport. Most of Ge entered the structure of huminite while a small amount of Ge was associated with residual humic acids as complex or humate. During hydrothermal transformation, the heated natural water or deep fluid from basement encountered the coal layer within tectonic weak zone. SO 2- 4 was reduced by coal organic matter. Pyrite and calcite formed. Hydrothermal process did not contribute significantly to mineralization.展开更多
Magnetite is a very common mineral in various types of iron deposits and some sulfide deposits. Recent studies have focused on the use of trace elements in magnetite to discriminate ore types or trace ore-forming proc...Magnetite is a very common mineral in various types of iron deposits and some sulfide deposits. Recent studies have focused on the use of trace elements in magnetite to discriminate ore types or trace ore-forming process. Germanium is a disperse element in the crust, but sometimes is not rare in magnetite. Germanium in magnetite can be determined by laser ablation ICP-MS due to its low detection limit（0.0X ppm）. In this study, we summary the Ge data of magnetite from magmatic deposits, iron formations, skarn deposits, iron oxide copper-gold deposits, and igneous derived hydrothermal deposits. Magnetite from iron formations contains relatively high Ge（up to ~250 ppm）, whereas those from all other deposits mostly contains Ge less than 10 ppm, indicating that iron formations can be discriminated from other Fe deposits by Ge contents. Germanium in magmatic/hydrothermal magnetite is controlled by a few factors. Primary magma/fluid composition may be the major control of Ge in magnetite. Higher oxygen fugacity may be beneficial to Ge partition into magnetite. Sulfur fugacity and temperature may have little effect on Ge in magnetite. The enrichment mechanism of Ge in magnetite from iron formations remains unknown due to the complex ore genesis. Germanium along with other elements（Mn, Ni, Ga） and element ratios（Ge/Ga and Ge/Si raios） can distinguish different types of deposits, indicating that Ge can be used as a discriminate factor like Ti and V. Because of the availability of in situ analytical technique like laser ablation ICP-MS, in situ Ge/Si ratio of magnetite can serve as a geochemical tracer and may provide new constraints on the genesis of banded iron formations.展开更多
文摘The mechanism of formation of the Lincang germanium deposit is discussed in thelight of the spatial distribution of Ge-rich coal and siliceous rocks, the sulfur isotopic composi-tion of pyrite in the Ge-rich coal, the variation of Ge abundance in the coal seams and the geo-chemical characteristics of the siliceous rocks. The results show that the siliceous rocks interca-lated with the coal seams were deposited from a hydrothermal medium through which germani-um was enriched in the coal beds. The primary source of germanium is thought to be the Ge-rich granite in the basement of the sedimentary basin.
文摘The mineralization is related closely to sedimentation, diagenesis and hydrothermal processes. In this paper, investigations are carried out on coal occurrence, maceral composition, inorganic minerals, trace elements and huminite reflectance. It is concluded that the source of Lincang superlarge deposit is mainly the muscovite granite in the west edge of the basin. During sedimentation, Ge (germanium) was leached out and entered the basin. Ge was adsorbed by lower organism and humic substances in water. Lincang lignite underwent three thermal processes: peatification, early diagenesis and hydrothermal transformation. During peatification, Ge was adsorbed or complexed by humic colloids. During early diagenesis, the Ge associated with humic acids was hard to mobilize or transport. Most of Ge entered the structure of huminite while a small amount of Ge was associated with residual humic acids as complex or humate. During hydrothermal transformation, the heated natural water or deep fluid from basement encountered the coal layer within tectonic weak zone. SO 2- 4 was reduced by coal organic matter. Pyrite and calcite formed. Hydrothermal process did not contribute significantly to mineralization.
基金funded by CAS“Light of West China”Program to YMMthe Key project of the National Natural Science Foundation of China(41230316)+3 种基金National Natural Science Foundation of China(41503039)the“CAS Hundred Talents”Project to JFG(Y5CJ038000)Research Initial Funding(Y4KJA20001 and Y5KJA20001)Independent Topics Fund(Y4CJ009000)of the Institute of Geochemistry,Chinese Academy of Sciences
文摘Magnetite is a very common mineral in various types of iron deposits and some sulfide deposits. Recent studies have focused on the use of trace elements in magnetite to discriminate ore types or trace ore-forming process. Germanium is a disperse element in the crust, but sometimes is not rare in magnetite. Germanium in magnetite can be determined by laser ablation ICP-MS due to its low detection limit（0.0X ppm）. In this study, we summary the Ge data of magnetite from magmatic deposits, iron formations, skarn deposits, iron oxide copper-gold deposits, and igneous derived hydrothermal deposits. Magnetite from iron formations contains relatively high Ge（up to ~250 ppm）, whereas those from all other deposits mostly contains Ge less than 10 ppm, indicating that iron formations can be discriminated from other Fe deposits by Ge contents. Germanium in magmatic/hydrothermal magnetite is controlled by a few factors. Primary magma/fluid composition may be the major control of Ge in magnetite. Higher oxygen fugacity may be beneficial to Ge partition into magnetite. Sulfur fugacity and temperature may have little effect on Ge in magnetite. The enrichment mechanism of Ge in magnetite from iron formations remains unknown due to the complex ore genesis. Germanium along with other elements（Mn, Ni, Ga） and element ratios（Ge/Ga and Ge/Si raios） can distinguish different types of deposits, indicating that Ge can be used as a discriminate factor like Ti and V. Because of the availability of in situ analytical technique like laser ablation ICP-MS, in situ Ge/Si ratio of magnetite can serve as a geochemical tracer and may provide new constraints on the genesis of banded iron formations.
文摘介绍了胜利煤-锗矿床的地质背景,以及锗在矿层的分布情况.胜利煤田处于二连盆地东端乌尼特坳陷中,为一宽缓向斜,地层平缓.胜利煤田煤-锗矿床发育于早白垩世断陷盆地内,位于二连盆地群中胜利煤盆的西南一隅,富锗矿层的分布受两侧F1,F2断层影响,呈现南部埋藏浅厚度薄、北部埋藏深厚度大的倾斜状特点;锗品位变化为南、北部较高(>400×10-6),东、西部较低(200×10-6左右)的"鞍"状分布特点,而向盆地中心急剧降低.沿煤层纵向上可以出现多个聚锗高值,个别钻孔煤层下部夹矸锗含量超过工业品位而具有工业价值,而煤层顶、底板锗含量都很低(<10×10-6),不具有工业价值.锗的分布,与成矿古地质、环境变化有关,受沼泽微环境和水动力影响,锗在煤层中的富集出现波动.采用"地质块段法"估算锗煤的资源量,资源量估算面积1.097 5 km2,估算结果锗资源量1 805 t.
