scholarly journals Are fluid inclusions in gypsum reliable paleoenvironmental indicators? An assessment of the evidence from the Messinian evaporites

Geology ◽  
2022 ◽  
Author(s):  
D. Bigi ◽  
S. Lugli ◽  
V. Manzi ◽  
M. Roveri
Keyword(s):  
Fluid Inclusions ◽  
Calcium Sulfate ◽  
Controversial Issue ◽  
Strong Mixing ◽  
Messinian Salinity Crisis ◽  
Lower Salinity ◽  
Low Salinity ◽  
Primary Fluid ◽  
Messinian Evaporites ◽  
Paleoenvironmental Indicators

The paleosalinity of water from which the gypsum precipitated during the Messinian salinity crisis is a controversial issue. Recent microthermometry studies on primary fluid inclusions in gypsum provided very low salinity values not compatible with precipitation from seawater, and suggested strong mixing between seawater and nonmarine waters enriched in calcium sulfate. We applied a new microthermometric protocol on gypsum crystals from nine Mediterranean sections that were experimentally stretched to measure a larger population of fluid inclusions. The results show salinities ranging from 9 to 238 wt‰ NaCl equivalent, largely falling within the evaporation path of normal seawater. The data from previous studies were obtained mostly from those fluid inclusions capable of nucleating a stable bubble after a weak stretching, which probably correspond to those having a lower salinity acquired through post-depositional crack-and-seal processes. Our data suggest instead that the primary gypsum precipitated from a marine brine, later modified by post-trapping processes during tectonics and exhumation.

scholarly journals Supplemental Material: Are fluid inclusions in gypsum reliable paleoenvironmental indicators? An assessment of the evidence from the Messinian evaporites

2021 ◽  
Author(s):  
Diego Bigi ◽  
et al.
Keyword(s):  
Fluid Inclusions ◽  
Additional Information ◽  
Messinian Evaporites ◽  
Paleoenvironmental Indicators

Additional information on the samples (Sr data, geographic and geological settings), a detailed description of the methods, and all microthermometric data obtained in this work.<br>

scholarly journals Supplemental Material: Are fluid inclusions in gypsum reliable paleoenvironmental indicators? An assessment of the evidence from the Messinian evaporites

2021 ◽  
Author(s):  
Diego Bigi ◽  
et al.
Keyword(s):  
Fluid Inclusions ◽  
Additional Information ◽  
Messinian Evaporites ◽  
Paleoenvironmental Indicators

Additional information on the samples (Sr data, geographic and geological settings), a detailed description of the methods, and all microthermometric data obtained in this work.<br>

scholarly journals Deposition conditions for the indium-bearing polymetallic quartz veins at Sarvlaxviken, south-eastern Finland

2018 ◽  
Vol 82 (S1) ◽  
pp. S43-S59 ◽  
Author(s):  
C. Broman ◽  
K. Sundblad ◽  
M. Valkama ◽  
A. Villar
Keyword(s):  
Fluid Inclusions ◽  
Complex Geometry ◽  
Vapour Phase ◽  
Turbulent Fluid Flow ◽  
Quartz Veins ◽  
Low Salinity ◽  
Depositional Processes ◽  
New Information ◽  
Primary Fluid ◽  
Opaque Minerals

ABSTRACTPolymetallic quartz veins, with up to 1500 ppm indium, have been discovered recently in the Sarvlaxviken area within the 1.64 Ga anorogenic multiphase Wiborg rapakivi batholith and adjacent 1.90 Ga Svecofennian crust in SE Finland. Evidence from primary fluid inclusions in the Sarvlaxviken area provides new information on the hydrothermal transport and depositional processes of metals in anorogenic granites. Fluid inclusions with variable aqueous liquid and vapour proportions (5–90 vol.% vapour) occur in quartz, cassiterite and fluorite belonging to three generations of polymetallic quartz veins. Microthermometry indicates that the veins were deposited at temperatures that range from ~500°C down to <100°C and salinities from 0 to 16 eq. mass% NaCl. Fluid inclusion data show that the depositional conditions were similar regardless of vein generation. The interpreted depositional processes involve phase separation with a combination of condensation, cooling and boiling of an initially low-salinity (<3 eq. mass% NaCl) aqueous magmatic vapour phase enriched in CO2-F-Cl-S and metals. Fluid inclusions with low salinities dominate, but higher salinities are recorded in metal-rich parts of the veins. The turbulent fluid flow, with complex geometry and temperature-salinity patterns, may explain why sulfide and/or oxide opaque minerals occur irregularly, and are locally the dominating vein minerals, but disappear completely into barren parts of the quartz veins. All fluids are considered to have been generated by the F-rich Marviken granite (and related granite dykes), which show all geochemical criteria for an ore-fertile granite. The quartz veins investigated in the adjacent Svecofennian country rocks are considered to represent the very last stage of a fluid with similar characteristics to the fluid responsible for the ore formation in the Sarvlaxviken area, but that had cooled to <100°C.

scholarly journals The Temperature of Halite Crystallization in the Badenian Saline Basins, in the Context of Paleoclimate Reconstruction of the Carpathian Area

Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 831
Author(s):  
Anatoliy R. Galamay ◽  
Krzysztof Bukowski ◽  
Igor M. Zinczuk ◽  
Fanwei Meng
Keyword(s):  
Temperature Distribution ◽  
Air Temperature ◽  
Fluid Inclusions ◽  
Middle Miocene ◽  
Single Phase ◽  
Dead Sea ◽  
Paleoclimate Reconstruction ◽  
Near Surface ◽  
Carpathian Region ◽  
Primary Fluid

Currently, fluid inclusions in halite have been frequently studied for the purpose of paleoclimate reconstruction. For example, to determine the air temperature in the Middle Miocene (Badenian), we examine single-phase primary fluid inclusions of the bottom halites (chevron and full-faceted) and near-surface (cumulate) halites collected from the salt-bearing deposits of the Carpathian region. Our analyses showed that the temperatures of near-bottom brines varied in ranges from 19.5 to 22.0 °C and 24.0 to 26.0 °C, while the temperatures of the surface brines ranged from 34.0 to 36.0 °C. Based on these data, such as an earlier study of lithology and sedimentary structures of the Badenian rock salts, the crystallization of bottom halite developed in the basin from concentrated and cooled near-surface brines of about 30 m depth. Our results comply with the data on the temperature distribution in the modern Dead Sea.

Oxygen fugacity during tin ore deposition from primary fluid inclusions in cassiterite

2021 ◽  
pp. 104451
Author(s):  
Christian Schmidt ◽  
Matthias Gottschalk ◽  
Rongqing Zhang ◽  
Jianjun Lu
Keyword(s):  
Oxygen Fugacity ◽  
Fluid Inclusions ◽  
Primary Fluid ◽  
Ore Deposition

Microanalysis of primary fluid inclusions in halite: constraints for an evaporitic sedimentation modeling. Application to the Mulhouse Basin (France)

1993 ◽  
Vol 20 (8) ◽  
pp. 1139-1151 ◽  
Author(s):  
A. Canals ◽  
B. Carpenter ◽  
A.Y. Huc ◽  
N. Guilhaumou ◽  
M.H. Ramsey
Keyword(s):  
Fluid Inclusions ◽  
Primary Fluid

scholarly journals The Ultramicrochemical Analyses (UMCA) of Fluid Inclusions in Halite and Experimental Research to Improve the Accuracy of Measurement

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 823 ◽  
Author(s):  
Anatoliy R. Galamay ◽  
Krzysztof Bukowski ◽  
Daria V. Sydor ◽  
Fanwei Meng
Keyword(s):  
Chemical Composition ◽  
Fluid Inclusions ◽  
Error Rates ◽  
Analytical Error ◽  
Genetic Types ◽  
Primary Fluid ◽  
Accuracy Of Measurement ◽  
Distinguishing Features ◽  
Geological Period

Fluid inclusions in halite are widely used in research to determine the conditions of sedimentation in salt basins and reconstruct the chemical composition of seawater during a specific geological period. However, previous preliminary studies of the genetic types of inclusions, considered in the present research project, have not received due attention. Consequently, we decided to take into account the main distinguishing features of fluid inclusions in halite, belonging to various genetic types. The ultramicrochemical analysis (UMCA) method is one of the several methods that are used for the quantitative determination of the chemical composition of the primary fluid inclusions in halite. We have upgraded that technique, and that allowed us to reduce the analytical error rates of each component determination. The error rates were calculated in the study of Ca-rich and SO4-rich types of natural sedimentary brines.

scholarly journals Paratethys pacing of the Messinian Salinity Crisis: Low salinity waters contributing to gypsum precipitation?

2020 ◽  
Vol 532 ◽  
pp. 116029 ◽  
Author(s):  
Arjen Grothe ◽  
Federico Andreetto ◽  
Gert-Jan Reichart ◽  
Mariette Wolthers ◽  
Christiaan G.C. Van Baak ◽  
...  
Keyword(s):  
Messinian Salinity Crisis ◽  
Low Salinity ◽  
Gypsum Precipitation

scholarly journals Ore Geology, Fluid Inclusions, and (H-O-S-Pb) Isotope Geochemistry of the Sediment-Hosted Antimony Mineralization, Lyhamyar Sb Deposit, Southern Shan Plateau, Eastern Myanmar: Implications for Ore Genesis

Minerals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 296
Author(s):  
Aung Min Oo ◽  
Lv Xinbiao ◽  
Khin Zaw ◽  
Than Htay ◽  
Sun Binke ◽  
...  
Keyword(s):  
Fluid Inclusions ◽  
Meteoric Water ◽  
Isotope Geochemistry ◽  
Pb Isotope ◽  
Primary Fluid ◽  
Magmatic Fluids ◽  
Homogenization Temperatures ◽  
Deposit Model ◽  
Fluid Homogenization ◽  
Stage Stage

The Lyhamyar deposit is a large Sb deposit in the Southern Shan Plateau, Eastern Myanmar. The deposit is located in the Early Silurian Linwe Formation, occurring as syntectonic quartz-stibnite veins. The ore body forms an irregular staircase shape, probably related to steep faulting. Based on the mineral assemblages and cross-cutting relationships, the deposit shows two mineralization stages: (1) the pre-ore sedimentary and diagenetic stage, and (2) the main-ore hydrothermal ore-forming stage (including stages I, II, and III), i.e., (i) early-ore stage (stage I) Quartz-Stibnite, (ii) late-ore stage (stage II) Quartz-calcite-Stibnite ± Pyrite, and (iii) post-ore stage (stage III) carbonate. The ore-forming fluid homogenization temperatures from the study of primary fluid inclusions in quartz and calcite indicate that the ore-forming fluid was of a low temperature (143.8–260.4 °C) and moderate to high-salinity (2.9–20.9 wt. % NaCl equivalent). Hydrogen and oxygen isotopes suggest that the ore-forming fluids of the Lyhamyar deposit were derived from circulating meteoric water mixed with magmatic fluids that underwent isotopic exchange with the surrounding rocks. Sulfur in Lyhamyar was dominated by thermochemical sulfate reduction (TSR) with dominant magmatic source sulfur. The lead isotope compositions of the stibnite indicate that the lead from the ore-forming metals was from the upper crustal lead reservoir and orogenic lead reservoir. On the basis of the integrated geological setting, ore geology, fluid inclusions, (H-O-S-Pb) isotope data, and previous literature, we propose a new ore-deposit model for the Lyhamyar Sb deposit: It was involved in an early deposition of pyrite in sedimentary and diagenetic stages and later Sb mineralization by mixing of circulating meteoric water with ascending magmatic fluids during the hydrothermal mineralization stage.

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