Three-Dimensional Visualization of the Archean Horne and Quemont Au-Bearing Volcanogenic Massive Sulfide Hydrothermal Systems, Blake River Group, Quebec,

• DOI: 10.2113/econgeo.109.1.183
• Publication Date: 2013-11-19T22:23:01Z
• Authors: B. E. Taylor; E. de Kemp; E. Grunsky; L. Martin; G. Maxwell; D. Rigg; J. Goutier; K. Lauziere; B. Dube
• Keywords: 01 natural sciences; 0105 earth and related environmental sciences

The hydrothermal system architecture related to the formation of contemporaneous Au-bearing Horne and Quemont volcanogenic massive sulfide (VMS) deposits was visualized by employing kriging methods map whole-rock oxygen isotope compositions, zones silica addition loss, water contents in two- three-dimension. Zones alteration were mapped three-dimensions vicinity steeply dipping deposit, depths as much 2 km. In all, nearly 300 samples analyzed for isotopes supplemented previously published analyses. Contents SiO2, H2O, MgO, Al2O3, S from chemical analyses 5,000 within three-dimensional study regions used separately, combination with data, modeling mapping purposes.

The formed a similar time frame, but different magmatic-hydrothermal systems, distinguished their architecture. deposit appears be centered on Powell pluton, which intruded late into an apparent volcanic-filled, rift-graben structure. Although structural complexities are apparent, we infer mineralizing high-temperature upflow footwall have emanated reaction zone above pluton (and its precursors), beneath extensive silicification. Faulting Andesite fault Creek faults, plus erosion, has removed evidence deposit.

Areas silicification correspond, general, isotopic lower temperature alteration. Such east signaled waning activity. suggested cooling, most part, promoted precipitation silica. case mixing metalliferous fluid cold seawater permeable rocks, apparently relatively stratigraphically stable long-lived system, evidently led marked silicified may contributed increased efficiency deposit. Continued intrusion some post-VMS activity is recorded hanging-wall section Our data suggest that deposition 10 million ounces (Moz) Au syngenetic, not product subsequent