Phase relations in the Cu-Fe-Zn-S system between 500 degrees and 300 degrees C under hydrothermal conditions

Kojima, Shoji; Sugaki, Asahiko

doi:10.2113/gsecongeo.80.1.158

Cited by 108 publications

(57 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The Co-bearing isocubanite must be mainly responsible for the high Co contents of the bulk sample analyses as noted previously. The maximum Zn content in isocubanite enclosing sphalerite, with many but tiny isocubanite blebs (Plate 1-4), is very close to 1.2 atomic%-the maximum solubility of Zn in iss at 300°C and 500 kg/cm 2 determined experimentally by Kojima and Sugaki (1985). The back-scattered electron images revealed that no Zn-rich phase is included in this isocubanite grain.…”

Section: Mineral Chemistry Isocubanitementioning

confidence: 59%

“…It seems likely, therefore, that the most Fe-rich isocubanite (Cu 149 Fe 354 Zn 0 ,|S 496 ) should be close in composition to the Fe-rich extremities of isocubanite. According to the hydrothermal experiments carried out between 300° and 500°C and a pressure of 500 kg/cm 2 in the system Cu-Fe-Zn-S (Kojima and Sugaki, 1985), the Fe content of iss increases with decreasing temperature, reaching the composition Cu 149 Fe 35 2 Zn 07 S 492 at 300°C which, except for the Zn content, is very close to the composition of the most Fe-rich isocubanite from Snake Pit. It is likely that the increase of Fe in isocubanite ceased at about 300°C, and with further decrease in temperature and the resultant exsolution of pyrrhotite, the trend in the compositional change of isocubanite reversed toward stoichiometric cubanite.…”

Section: Mineral Deposition Exsolution and Alterationmentioning

confidence: 94%

See 1 more Smart Citation

Copper-Rich Sulfide Deposit Near 23°N, Mid-Atlantic Ridge: Chemical Composition, Mineral Chemistry, and Sulfur Isotopes

Kase¹,

Yamamoto²,

Shibata³

1990

Proceedings of the Ocean Drilling Program

View full text Add to dashboard Cite

In Snake Pit massive sulfide fragments and friable, unconsolidated material recovered during ODP Leg 106, isocubanite and pyrite are generally the predominant phases, followed by marcasite, chalcopyrite, sphalerite, and pyrrhotite. Detailed analyses of paragenetic relations of minerals indicate that isocubanite first precipitated together with pyrrhotite. With decreasing temperature, chalcopyrite and sphalerite precipitated, and at the latest stage colloform sphalerite-pyrite (or colloform marcasite) formed. Isocubanite usually has exsolution lamellae of chalcopyrite and less commonly of pyrrhotite.The average bulk chemical composition of the friable, unconsolidated material indicates that it is rich in copper, reflecting the dominance of isocubanite in the specimens, and is characterized by high Co, low Pb, and Ag contents. Sulfur isotope ratios are very uniform, ranging in S 34 S from +1.2 to +2.8%c. The obtained values are apparently low, compared to those for the eastern Pacific sulfide samples, reflecting a smaller contribution of seawater sulfate in the Snake Pit sulfide deposit.

show abstract

Section: Mineral Chemistry Isocubanitementioning

confidence: 59%

Section: Mineral Deposition Exsolution and Alterationmentioning

confidence: 94%

Copper-Rich Sulfide Deposit Near 23°N, Mid-Atlantic Ridge: Chemical Composition, Mineral Chemistry, and Sulfur Isotopes

Kase¹,

Yamamoto²,

Shibata³

1990

Proceedings of the Ocean Drilling Program

View full text Add to dashboard Cite

show abstract

“…The idea that more Fe-rich intermediate solid solutions (e.g., CuFe 2 S 3 , CuFe 3 S 4 ) will host higher Co concentrations than chalcopyrite has been previously proposed (e.g., . Such Fe-rich compositions are associated with lower sulfidation states which are in turn associated with more mafic lithologies (Kojima and Sugaki, 1985;Einaudi, 2006 and Eastern Lau Spreading Center (Chapter 2 of this thesis), likewise measured by electron microprobe. Results reported as weight percent normalized to total = Cu (wt%) + Fe (wt%) + S (wt%).…”

Section: Ga and Inmentioning

confidence: 89%

Trace element proxies and mineral indicators of hydrothermal fluid composition and seafloor massive sulfide deposit formation processes

Evans¹

2017

View full text Add to dashboard Cite

THESIS ABSTRACTThis thesis analyzes compositions of seafloor massive sulfide (SMS) deposits and related hydrothermal vent fluids to identify proxies of reaction zone conditions (host-rock lithology, hydrothermal fluid temperature and chemistry). Chapter 2 investigates the morphology, mineralogy, and geochemistry of SMS deposits from six vent fields along the Eastern Lau Spreading Center (ELSC), demonstrating that ELSC SMS deposits record differences in hydrothermal fluid temperature, pH, sulfur fugacity and host-rock lithology related to proximity to the nearby Tonga Subduction Zone. Chapters 3 and 4 focus on partitioning of Co, Ni, Ga, Ag, and In between hydrothermal vent fluids and chalcopyrite lining fluid conduits in black smoker chimneys. Chapter 3 develops secondary ion mass spectrometry (SIMS) as a technique to measure Co, Ni, Ga, Ag, and In in chalcopyrite and identifies a correlation between Ga and In in chalcopyrite and hydrothermal fluid pH. Chapter 4 presents new data on these elements in ELSC hydrothermal fluids that, combined with SIMS analyses of chalcopyrite chimney linings and previously published data on vent fluids from the Manus Basin, provide evidence that supports partitioning of Ag a lattice substitution for Cu. Together, concentrations of Ga, In, and Ag in chalcopyrite provide proxies of hydrothermal fluid pH and metal (i.e., Ag and Cu) contents. ACKNOWLEDGEMENTSThe work presented in this thesis could not have been accomplished without a network of professional and personal support. To that end, I would like to acknowledge my advisor, Dr. Margaret K. Tivey, for her mentorship and dedication, and members of my thesis committee: Dr. Jeffrey S. Seewald, Dr. Nobumichi Shimizu, Prof. Shuhei Ono, and Prof. Olivier J. Rouxel for their valuable input and advice to improve the contents of this thesis. Dr. Brian Monteleone's help in developing secondary ion mass spectrometry of trace elements in sulfide minerals and Margaret Sulanowska's help with sample preparation are also greatly acknowledged, as are Dr. Paul R. Craddock and Dr. Jill M. McDermott, my predecessors in the MIT/WHOI Joint Program, whose theses provided significant contributions to the work presented here.I would also like to acknowledge the captains and crews of the R/V Melville, the R/V Thompson, the R/V Atlantis III, and the R/V Roger Revelle, and the team of the ROV Jason II for their expertise in recovering fluid and SMS deposit samples from active vent fields, as well as chief scientists, Dr. Chris German (AT18-16) and Prof. Anna-Louise Reysenbach (RR1507) for welcoming my participation on research cruises to the Mid-Cayman Rise and Eastern Lau Spreading Center. Work presented in Chapter 2 of this thesis was supported by the National Science Foundation through grants OCE-1038135 to GNE and MKT, OCE-1038124, OCE-0241796, OCE-1233037 to JSS, and OCE-0242088 to CGW. Chapters 3 and 4 were supported by the National Science Foundation through grants OCE-1038135 and NSF Graduate Research Fellowship to GNE and funding from grant NSF O...

show abstract

“…% and hence is below the 2 wt. % threshold suggested by many authors (Kojima and Sugaki, 1985;Tesfaye Firdu and Taskinen, 2010;Keith et al, 2014) as indicative of preservation of primary compositions and minor impact of remobilization or chalcopyrite disease. Nevertheless, as trends towards Cu enrichment do exist in the analyzed sphalerite grains (Fig.…”

Section: Ore Mineral Geochemistrymentioning

confidence: 98%

Mineralogy, geochemistry and sulfur isotope characterization of Cerro de Maimón (Dominican Republic), San Fernando and Antonio (Cuba) lower Cretaceous VMS deposits: Formation during subduction initiation of the proto-Caribbean lithosphere within a fore-arc

Torró

Proenza

Melgarejo

et al. 2016

Ore Geology Reviews

View full text Add to dashboard Cite

Phase relations in the Cu-Fe-Zn-S system between 500 degrees and 300 degrees C under hydrothermal conditions

Cited by 108 publications

References 0 publications

Copper-Rich Sulfide Deposit Near 23°N, Mid-Atlantic Ridge: Chemical Composition, Mineral Chemistry, and Sulfur Isotopes

Copper-Rich Sulfide Deposit Near 23°N, Mid-Atlantic Ridge: Chemical Composition, Mineral Chemistry, and Sulfur Isotopes

Trace element proxies and mineral indicators of hydrothermal fluid composition and seafloor massive sulfide deposit formation processes

Mineralogy, geochemistry and sulfur isotope characterization of Cerro de Maimón (Dominican Republic), San Fernando and Antonio (Cuba) lower Cretaceous VMS deposits: Formation during subduction initiation of the proto-Caribbean lithosphere within a fore-arc

Contact Info

Product

Resources

About