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

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.

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First report on the occurrence of CO2-bearing fluid inclusions in the Meiduk porphyry copper deposit, Iran: implications for mineralisation processes in a continental collision setting

Geologos ◽

10.2478/logos-2013-0019 ◽

2013 ◽

Vol 19 (4) ◽

pp. 301-320 ◽

Cited By ~ 15

Author(s):

Sina Asadi ◽

Farid Moore ◽

Alireza Zarasvandi ◽

Majid Khosrojerdi

Keyword(s):

Fluid Inclusions ◽

Porphyry Copper ◽

Copper Deposit ◽

Porphyry Copper Deposit ◽

Laser Raman Spectroscopy ◽

Type I ◽

Quartz Veins ◽

Three Phase ◽

Stage 1 ◽

Multi Phase

Abstract Hydrothermal alteration of the Meiduk porphyry copper deposit, south of the Kerman Cenozoic magmatic arc and southeast of the central Iranian volcano-plutonic belt has resulted in three stages of mineralisation characterised by veins and veinlets. These are, from early to late: (1) quartz + K-feldspar + biotite + pyrite ± chalcopyrite ± pyrrhotite ± magnetite (early potassic alteration and type-A veins); (2) quartz + chalcopyrite + pyrite + bornite + pyrrhotite + K- -feldspar + biotite + magnetite (potassic-sericitic alteration and type-B veins); and (3) quartz + pyrite + chalcopyrite + sericite (sericitic alteration and type-C veins). Most ores were formed during stages 2 and 3. Three main types of fluid inclusions are distinguished based on petrographical, microthermometrical and laser Raman spectroscopy analyses, i.e. type I (three-phase aqueous inclusions), type II (three-phase liquid-carbonic inclusions) and type III (multi-phase solid inclusions). The fluid inclusions in quartz veins of the stages are mainly homogenised at 340-530°C (stage 1), 270-385°C (stage 2) and 214-350°C (stage 3), respectively, with salinities of 3.1-16 wt.% NaCl equivalent, 2.2-43 wt.% NaCl equivalent and 8.2-22.8 wt.% NaCl equivalent, respectively. The estimated trapping pressures are 97.9-123.6 MPa (3.7-4.6 km) in stage 1 and 62.5-86.1 MPa (2.3-3.1 km) in stage 2, respectively. These fluid inclusions are homogenised in different ways at similar temperatures, suggesting that fluid boiling took place in stages 2 and 3. The fluid system evolved from high-temperature, medium-salinity, high-pressure and CO2-rich to low-temperature, low-pressure, high-salinity and CO2-poor, with fluid boiling being the dominating mechanism, followed by input of meteoric water. CO2 escape may have been a factor in increasing activities of NaCl and S2- in the fluids, diminishing the oxidation of the fluids from stage 1 to 3. The result was precipitation of sulphides and trapping of multi-phase solid inclusions in hydrothermal quartz veins.

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

Geofluids ◽

10.1155/2020/7352821 ◽

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.

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Hydrothermal fluid evolution in the Escondida porphyry copper deposit, northern Chile: evidence from SEM-CL imaging of quartz veins and LA-ICP-MS of fluid inclusions

Mineralium Deposita ◽

10.1007/s00126-021-01058-z ◽

2021 ◽

Author(s):

Karl Riveros Jensen ◽

Eduardo Campos ◽

Jamie J. Wilkinson ◽

Clara C. Wilkinson ◽

Anton Kearsley ◽

...

Keyword(s):

Fluid Inclusions ◽

Hydrothermal Fluid ◽

Porphyry Copper ◽

Copper Deposit ◽

Porphyry Copper Deposit ◽

Northern Chile ◽

Quartz Veins ◽

Fluid Evolution ◽

Icp Ms

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Ore Genesis of the Kuergasheng Pb–Zn Deposit, Xinjiang Province, Northwest China: Constraints from Geology, Fluid Inclusions, and H–O–C–S–Pb Isotopes

Minerals ◽

10.3390/min10070592 ◽

2020 ◽

Vol 10 (7) ◽

pp. 592

Author(s):

Shunda Li ◽

Chuan Chen ◽

Lingling Gao ◽

Fang Xia ◽

Xuebing Zhang ◽

...

Keyword(s):

Fluid Inclusions ◽

Northwest China ◽

Hybrid Origin ◽

Isotopic Data ◽

Quartz Veins ◽

Carbon Isotopic ◽

Ore Bodies ◽

Western Tianshan ◽

Homogenization Temperatures ◽

Stage 1

The Kuergasheng Pb–Zn deposit is located in the Western Tianshan Orogen, Xinjiang Province, China. The ore bodies are mainly hosted in sandstone of the Tuosikuertawu Formation and are controlled by NW-trending faults. Three paragenetic stages were identified: early pyrite–chalcopyrite–quartz veins (stage 1), middle galena–sphalerite–quartz veins (stage 2), and late sulfide-poor calcite–quartz veins (stage 3). Fluid inclusions (FIs) include liquid-rich aqueous (LV-type), vapor-rich aqueous (VL-type), halite-bearing (S-type), and monophase liquid aqueous (L-type). Homogenization temperatures for FIs from stages 1–3 are 221–251, 173–220, and 145–172 °C, respectively. Stage 1 fluids in LV-, VL-, and S-type FIs yield salinities of 6.2–9.6, 1.7–3.1, and 32.7–34.9 wt % NaCl equiv., respectively. Stage 2 fluids in LV- and S-type FIs have salinities of 5.1–7.9 and 31.9–32.1 wt % NaCl equiv., respectively. Stage 3 fluids in LV- and L-type FIs have salinities of 3.4–5.9 wt % NaCl equiv. Oxygen, hydrogen, and carbon isotopic data (δ18OH2O = −7.7 to 1.7‰, δDH2O = −99.2 to −83.1‰, δ13CH2O = −16.6 to 9.1‰) indicate that the ore-forming fluids have a hybrid origin —an initial magmatic source with input of meteoric water becoming dominant in the later stage. Sulfur and lead isotopic data for galena (δ34S = 5.6 to 6.9‰, 206Pb/204Pb = 18.002–18.273, 207Pb/204Pb = 15.598–15.643, 208Pb/204Pb = 38.097–38.209) reveal that the ore-forming materials were mainly derived from the Beidabate intrusive body and the Tuosikuertawu Formation.

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Design of objective lens for 200-kV high-resolution electron microscopes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075361 ◽

1983 ◽

Vol 41 ◽

pp. 314-315

Author(s):

K. Tsuno ◽

T. Honda ◽

Y. Harada ◽

M. Naruse

Keyword(s):

Optical Properties ◽

Computer Technology ◽

Axial Magnetic Field ◽

Chromatic Aberration ◽

Objective Lens ◽

Resolution Electron ◽

Correction Of Astigmatism ◽

Three Stages ◽

Electron Microscopes ◽

Stage 1

Developement of computer technology provides much improvements on electron microscopy, such as simulation of images, reconstruction of images and automatic controll of microscopes (auto-focussing and auto-correction of astigmatism) and design of electron microscope lenses by using a finite element method (FEM). In this investigation, procedures for simulating the optical properties of objective lenses of HREM and the characteristics of the new lens for HREM at 200 kV are described.The process for designing the objective lens is divided into three stages. Stage 1 is the process for estimating the optical properties of the lens. Firstly, calculation by FEM is made for simulating the axial magnetic field distributions Bzc of the lens. Secondly, electron ray trajectory is numerically calculated by using Bzc. And lastly, using Bzc and ray trajectory, spherical and chromatic aberration coefficients Cs and Cc are numerically calculated. Above calculations are repeated by changing the shape of lens until! to find an optimum aberration coefficients.

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Middle and Late Jurassic Radiolarians from Nadanhada Terrane of Eastern Heilongjiang Province, Northeastern China

Paleontological Research ◽

10.2517/2019pr006 ◽

2019 ◽

Vol 23 (4) ◽

pp. 291 ◽

Cited By ~ 3

Author(s):

Gang Li ◽

Atsushi Matsuoka ◽

Qun Yang ◽

Jingeng Sha

Keyword(s):

Late Jurassic ◽

Northeastern China ◽

Heilongjiang Province

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A COVID-19 Lockdown Tabletop Exercise in New Taipei City, Taiwan

Disaster Medicine and Public Health Preparedness ◽

10.1017/dmp.2021.35 ◽

2021 ◽

pp. 1-19

Author(s):

I-Tien Lo ◽

Ching-Yuan Lin ◽

Ming-Tai Cheng

Keyword(s):

Policy Making ◽

Large City ◽

Strategic Plan ◽

Government Control ◽

Subject Knowledge ◽

All Solutions ◽

Taipei City ◽

Returning To Work ◽

Three Stages ◽

Stage 1

Abstract Objectives: This exercise aimed to validate New Taipei City’s strategic plan for a city lockdown in response to COVID-19. The main goal of all solutions was the principle of “reducing citizen activity and strengthening government control”. Methods: We created a suitable exercise, and creating 15 hypothetical situations for three stages. All participating units designed and proposed policy plans and execution protocols according to each situation. Results: In the course of the exercise, many existing policies and execution protocols were validated to address. Situations occurring in Stage 1, when the epidemic was spreading to the point of lockdown preparations, approaches to curb the continued spread of the epidemic in Stage 2, and returning to work after the epidemic is controlled and lockdown is lifted in Stage 3. Twenty response units participated in the exercise. Although favourable outcomes were obtained, the evaluators provided comments suggesting further improvements. Conclusions: Our exercise demonstrated a successful example to help policy making and revision in a large city over 4 million population during COVID-19 pandemic. It also enhanced participants’ subject knowledge and familiarity with the implementation of a city lockdown. For locations intending to go into lockdown, similar tabletop exercises are an effective verification option.

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