scholarly journals Fluid Inclusions and S–Pb Isotopes of the Reshui Porphyry Mo Deposit in East Kunlun, Qinghai Province, China

Minerals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 547
Author(s):  
Xianzheng Guo ◽  
Xinbiao Lü ◽  
Qunzi Jia ◽  
Jinchao Li ◽  
Huilei Kong
Keyword(s):  
Fluid Inclusions ◽  
Pb Isotopes ◽  
Pure Liquid ◽  
Fluid Temperature ◽  
Forming Process ◽  
Medium Temperature ◽  
East Kunlun ◽  
Porphyry Mo Deposit ◽  
Stage 1 ◽  
Stage Stage

The Reshui porphyry Mo deposit is located in the East Kunlun orogenic belt (EKOB). Molybdenum mineralization is distributed in monzogranite and porphyritic monzogranite rocks, mainly presenting as various types of hydrothermal veinlets in altered wall rocks, and the orebodies are controlled by three groups of fractures. In this paper, we present the results of fluid-inclusion and isotopic (S and Pb) investigations of the Reshui Mo deposit. The ore-forming process of the deposit can be divided into three stages: an early disseminated molybdenite stage (stage 1), a middle quartz–molybdenite stage (stage 2) and a late quartz–polymetallic sulfide stage (stage 3). The alteration was mainly potassic and silicic in stage 1, silicic in stage 2, and sericitic and silicic in stage 3. Five types of fluid inclusions (FIs) can be distinguished in quartz phenocrysts and quartz veins, namely W, PL (pure liquid inclusions), PV (pure gas inclusions), C (CO2 three-phase inclusions), and S (daughter mineral-bearing inclusions). The homogenization temperatures of fluid inclusions belonging to stages 1 to 3 are 282.3–378 °C, 238.7–312.6 °C and 198.3–228 °C, respectively. The fluid salinities at stages 1 to 3 are 4.65–8.14% NaCl eq., 4.34–42.64% NaCl eq., and 3.55–4.65% NaCl eq., respectively. The fluids of this deposit were generally moderate–high temperature and moderate–low salinity and belong to the H2O–NaCl–CO2 ± CH4 system. The temperature and pressure changed considerably between stage 2 (high–medium-temperature) and stage 3 (low-temperature). The evidence for ore-forming fluids containing different types of coexisting inclusions in stage 2 and a decrease in the fluid temperature from stage 2 to stage 3 indicate that fluid boiling and fluid mixing were the main mechanisms of ore precipitation. The sulfide 34SV-CDT values range from 4.90‰ to 5.80‰, which is characteristic of magmatic sulfur. The 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb values of the ore minerals are 18.210–18.786, 15.589–15.723, and 38.298–39.126, respectively. These lead isotopic compositions suggest that the ores were mainly sourced from crustally derived magmas, with minor input from the mantle. The fluid inclusions and S–Pb isotopes provide important information on the genesis of the Reshui porphyry Mo deposit and indicate that the Triassic has high metallogenic porphyry potential in the EKOB.

Ore geology, fluid inclusions, and C–H–O–S–Pb isotopes of Nagengkangqieergou Ag‐polymetallic deposit, East Kunlun Orogen, NW China

2020 ◽  
Vol 55 (4) ◽  
pp. 2572-2590
Author(s):  
Xiao‐Dong Chen ◽  
You‐Guo Li ◽  
Min‐Tong Li ◽  
Hong‐Bing Zhou ◽  
Chong‐Bo Sun ◽  
...  
Keyword(s):  
Fluid Inclusions ◽  
Pb Isotopes ◽  
Nw China ◽  
Polymetallic Deposit ◽  
East Kunlun

Mineralization of Luziyuan Pb–Zn skarn deposit, Baoshan, Yunnan Province, SW China: evidence from petrography, fluid inclusions and stable isotopes

2018 ◽  
Vol 156 (4) ◽  
pp. 639-658 ◽  
Author(s):  
YU-LONG YANG ◽  
LIN YE ◽  
TAN BAO ◽  
WEI GAO ◽  
ZHEN-LI LI
Keyword(s):  
Inductively Coupled Plasma ◽  
Meteoric Water ◽  
Fluid Temperature ◽  
Skarn Deposit ◽  
Sw China ◽  
Magmatic Water ◽  
Quartz Veins ◽  
Stage 4 ◽  
Stage 1 ◽  
Stage Stage

AbstractThe Luziyuan Pb–Zn skarn deposit, located in the Baoshan–Narong–Dongzhi block metallogenic belt in SW China, is hosted by marble and slate in the upper Cambrian Shahechang Formation. Three skarn zones have been identified from the surface (1495 m above sea level (asl)) to a depth of 1220 m asl: zone 1 consists of chlorite–actinolite–calcite–quartz, zone 2 of rhodonite–actinolite–fluorite–quartz–calcite, and zone 3 contains garnet–rhodonite–actinolite–fluorite–quartz–calcite. The deposit formed in four distinct mineralization stages: an early anhydrous skarn (garnet, rhodonite and bustamite) stage (Stage 1), a hydrous skarn (actinolite and chlorite) stage (Stage 2), an early quartz (coarse barren quartz veins) stage (Stage 3) and a late sulphide-forming (fine sulphide-bearing quartz veins) stage (Stage 4). The Stage 1 skarn-forming fluid temperature was at least 500 °C according to the geothermometer with rhodonite/bustamite trace elements measured by laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS). A decrease in ore fluid temperatures with time is consistent with the decreases in the δ18Ofluid and δDfluid values from Stage 3 to 4. This trend suggests that the ore fluid was mainly derived from magmatic water and mixed with large amounts of meteoric water during mineralization. The δ34S values of Stage 4 chalcopyrite, sphalerite and galena are similar to those of an Ordovician gypsum layer, and together with the high-salinity fluids in Stage 4 indicate the dissolution of evaporites in the Luziyuan region. Overall, the results of this study suggest that the Luziyuan deposit is a distal Pb–Zn skarn deposit that formed in response to multi-stage alteration associated with a combination of magmatic water and meteoric water.

scholarly journals Ore Genesis at the Jinchang Gold–Copper Deposit in Heilongjiang Province, Northeastern China: Evidence from Geology, Fluid Inclusions, and H–O–S Isotopes

Minerals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 99 ◽  
Author(s):  
Shunda Li ◽  
Xuebing Zhang ◽  
Lingling Gao
Keyword(s):  
Fluid Inclusions ◽  
Copper Deposit ◽  
Northeastern China ◽  
Heilongjiang Province ◽  
Quartz Veins ◽  
Daughter Mineral ◽  
Rich Liquid ◽  
Three Stages ◽  
Stage 1 ◽  
Late Stages

The Jinchang gold–copper deposit is located in Eastern Heilongjiang Province,Northeastern China. The orebody comprises primarily hydrothermal breccias, quartz veins, anddisseminated ores within granite, diorite, and granodiorite. Three paragenetic stages are identified:early quartz–pyrite–arsenopyrite (Stage 1), quartz–pyrite–chalcopyrite (Stage 2), and latequartz–pyrite–galena–sphalerite (Stage 3). Gold was deposited during all three stages and Stage 1was the major gold-producing stage. Copper is associated with the mineralization but has loweconomic value. Fluid inclusions (FIs) within the deposit are liquid-rich aqueous, vapor-rich aqueous,and daughter-mineral-bearing types. Microthermometric data for the FIs reveal decreasinghomogenization temperatures (Th) and salinities of the ore-forming fluids over time. The Th forStages 1–3 of the mineralization are 421–479, 363–408, and 296–347 °C, respectively. Stage 1 fluidsin vapor-rich and daughter-mineral-bearing inclusions have salinities of 5.7–8.7 and 49.8–54.4 wt%NaCl equivalent, respectively. Stage 2 fluids in vapor-rich, liquid-rich, and daughter-mineral-bearinginclusions have salinities of 1.2–5.4, 9.5–16.0, and 43.3–48.3 wt% NaCl, respectively. Stage 3 fluids inliquid-rich and daughter-mineral-bearing inclusions have salinities of 7.9–12.6 and 38.3–42.0 wt% NaClequivalent, respectively. The estimated trapping pressures are 160–220 bar, corresponding toan entrapment depth of 1.6–1.2 km in the paleo-water table. Oxygen and hydrogen isotope data(δ18OV-SMOW = 8.6‰ to 11.4‰; δDV-SMOW = −92.2‰ to −72.1‰) suggest that the ore-forming fluidswere derived from magmatic fluids during the early stages of mineralization and subsequentlyincorporated meteoric water during the late stages. The sulfide minerals have δ34SVCDT values of0.2‰–3.5‰, suggesting that the sulfur has a magmatic origin. The Jinchang deposit is a typicalgold-rich gold–copper porphyry deposit.

Mineralogy, fluid inclusions and C–H–O–S–Pb isotopes of the Palaeocene Longgen Pb-Zn deposit in the western Nyainqentanglha belt, Tibet

2018 ◽  
Vol 102 ◽  
pp. 18-43 ◽  
Author(s):  
Yong-chao Zhang ◽  
Shun-bao Gao ◽  
You-ye Zheng ◽  
Jun-sheng Jiang ◽  
Shu-zhi Zhang ◽  
...  
Keyword(s):  
Fluid Inclusions ◽  
Pb Isotopes

scholarly journals Genesis of the Longmendian Ag–Pb–Zn Deposit in Henan (Central China): Constraints from Fluid Inclusions and H–C–O–S–Pb Isotopes

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-21
Author(s):  
Xinglin Chen ◽  
Yongjun Shao ◽  
Chunkit Lai ◽  
Cheng Wang
Keyword(s):  
Fluid Inclusions ◽  
Central China ◽  
Granitic Magma ◽  
Two Phase ◽  
Quartz Veins ◽  
The North ◽  
Granitic Magmatism ◽  
Polymetallic Sulfides ◽  
Homogenization Temperatures ◽  
Stage 1

The Longmendian Ag–Pb–Zn deposit is located in the southern margin of the North China Craton, and the mineralization occurs mainly in quartz veins, altered gneissic wallrocks, and minor fault breccias in the Taihua Group. Based on vein crosscutting relations, mineral assemblages, and paragenesis, the mineralization can be divided into three stages: (1) quartz–pyrite, (2) quartz–polymetallic sulfides, and (3) quartz–carbonate–polymetallic sulfides. Wallrock alteration can be divided into three zones, i.e., chlorite–sericite, quartz–carbonate–sericite, and silicate. Fluid inclusions in all Stage 1 to 3 quartz are dominated by vapor-liquid two-phase aqueous type (W-type). Petrographic and microthermometric analyses of the fluid inclusions indicate that the homogenization temperatures of Stages 1, 2, and 3 are 198–332°C, 132–260°C, and 97–166°C, with salinities of 4.0–13.3, 1.1–13.1, and 1.9–7.6 wt% NaCleqv, respectively. The vapor comprises primarily H2O, with some CO2, H2, CO, N2, and CH4. The liquid phase contains Ca2+, Na+, K+, SO42−, Cl−, and F−. The sulfides have δ34S=–1.42 to +2.35‰ and 208Pb/204Pb=37.771 to 38.795, 207Pb/204Pb=15.388 to 15.686, and 206Pb/204Pb=17.660 to 18.101. The H–C–O–S–Pb isotope compositions indicate that the ore-forming materials may have been derived from the Taihua Group and the granitic magma. The fluid boiling and cooling and mixing with meteoric water may have been critical for the Ag–Pb–Zn ore precipitation. Geological and geochemical characteristics of the Longmendian deposit indicate that the deposit is best classified as medium- to low-temperature intermediate-sulfidation (LS/IS) epithermal-type, related to Cretaceous crustal-extension-related granitic magmatism.

Process-adapted temperature application within a two-stage rivet forming process for high nitrogen steel

2022 ◽  
pp. 146442072110686
Author(s):  
C-M Kuball ◽  
B Uhe ◽  
G Meschut ◽  
M Merklein
Keyword(s):  
Room Temperature ◽  
Temperature Management ◽  
High Nitrogen Steel ◽  
High Nitrogen ◽  
Forming Process ◽  
Two Stage ◽  
Nitrogen Steel ◽  
Temperature Application ◽  
Stage 1 ◽  
Forming Behaviour

Mechanical joining technologies like self-piercing riveting are gaining importance with regard to environmental protection, as they enable multi-material design and lightweight construction. A new approach is the use of high nitrogen steel as rivet material, which allows to omit the usually necessary heat treatment and coating and thus leads to a shortening of the process chain. Due to the high strain hardening, however, high tool loads must be expected. Thus, appropriate forming strategies are needed. Within this contribution, the influence of applying different temperatures for each forming stage in a two-stage rivet forming process using the high nitrogen steel 1.3815 is investigated. The findings provide a basic understanding of the influence of the temperature management when forming high nitrogen steel. For this purpose, the rivets are not formed at the same temperature in each stage, but an elevated temperature is applied selectively. Different process routes are investigated. First, cups are manufactured in stage 1 at room temperature, followed by stage 2 at 200°C. Second, cups are formed in stage 1 at 200°C and used for stage 2 at room temperature. By comparing the findings with results when applying the same temperature in both stages, it is shown that the temperature during the first forming operation has an effect on the forming behaviour during the second forming stage. The required forming forces and the resulting rivet hardness can be influenced by process-adapted temperature application. Furthermore, the causes for the temperature impact on the residual cup thickness in stage 1 are evaluated by a cause and effect analysis, which provides a deeper process understanding. The thermal expansion of the tool and the billet as well as the improved forming behaviour at 200°C are identified as the main influencing causes on the achieved residual cup thickness.

The fluorite vein mineralization of the southern Alps: combined application of fluid inclusions and rare earth element (REE) distribution

1990 ◽  
Vol 54 (375) ◽  
pp. 325-333 ◽  
Author(s):  
U. F. Hein ◽  
V. Lüders ◽  
P. Dulski
Keyword(s):  
Fluid Inclusions ◽  
Large Scale ◽  
Genetic Model ◽  
Distribution Patterns ◽  
Southern Alps ◽  
Homogeneous Fluid ◽  
Medium Temperature ◽  
Combined Application ◽  
Vein Formation ◽  
Reducing Conditions

AbstractThe fluorite vein deposits of the Southern Alps (Northern Italy) exhibit similar geotectonic, paragenetic, and textural characteristics permitting useful comparison between their fluid inclusions and REE systematics. Due to differing post-crystallization deformation, primary fluid inclusions can only be observed in the northernmost deposit (Rabenstein/Corvara). Here, fluorite precipitated from highly saline H2O-NaCl-CaCl2 solutions containing appreciable H2S. During vein formation the fluids changed from low salinity (≈7 wt. % NaCl equiv.) and medium temperature (Th ≈ 230°C), corresponding to the precipitation of early quartz, towards high salinity (≈20 wt.% NaCl equiv.) and lower temperatures (Th ≈170°C during the deposition of late-stage fluorite. This was accompanied by an increase in Ca in solution.REE distribution patterns for the northern deposits are very uniform suggesting a similar source, a large-scale homogeneous fluid system, and fluorite precipitation under reducing conditions. By comparison the southern deposits exhibit contrasting patterns documenting a more complex history, probably due to their remobilization from an earlier mineralization. None of the fluorites shows a ‘primary’ magmatic REE distribution pattern, thereby favouring a genetic model for fluorite mineralization involving the leaching of suitable rock units by formation waters.

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