Description

Location: Western Folklife Center, Elko, NV

Contact: ajeet@megllc.net

 GSN Elko Chapter Meeting

Thursday, February 20, 2025

Western Folklife Center, 501 Railroad St., Elko, NV

Drinks and Appetizers at 6 pm; Talk at 7 pm

 Speaker: Marcus Angus, Master’s Student, CREG Program and partially funded by GSN Scholarships

Title: Constraining Mineralization and Alteration Through New Geologic Mapping at Spring Peak Low-Sulfidation Epithermal  System, Mineral County, NV

 FOOD & DRINKS SPONSORS: COEUR PRODUCTS

 ABSTRACT:
Marcus J. Angus, Simon Jowitt
Ralph J. Roberts Center for Research in Economic Geology, Department of Geological Sciences and Engineering,     University of Nevada, Reno
Spring Peak is a newly discovered sinter-vein system in Mineral County, NV with a well-preserved epithermal footprint at surface and is being actively explored by Headwater Gold, Inc. The Spring Peak system is hosted within a region constructed of Mesozoic metavolcanics and metasediments, Cretaceous granitic rocks related to satellite plutons of the Sierra Nevada batholith, Miocene subduction-related volcanics and associated volcaniclastics, and Late Pliocene-Pleistocene volcanic centers. The age of mineralization at Spring Peak has yet to be constrained and pending 40Ar/39Ar dating of adularia in mineralized drill core, coupled with rhyolite domes collected at surface, will determine whether Spring Peak has similar Miocene mineralization analogous to the nearby Aurora Mining District, or if Spring Peak is a potentially younger sinter-vein system. High-grade gold mineralization (>15g/t) occurs on property within boiling horizons of structurally controlled hydrothermal upwelling zones. One of these upwelling zones lies directly beneath the outcropping sinter, where high-temperature sinter lithofacies (geyserite) overlies adularia altered and silicified volcanic epiclastic sediments. Sinters are surficial expressions of low-sulfidation epithermal systems and form where silica oversaturated alkali-chloride fluids are expelled in hot spring deposits, forming a predictable gradient in lithofacies with distance from the vent source. New geologic mapping at Spring Peak aims to describe lithology, trends in alteration, and identify favorable structural controls in order to delineate additional upwelling zones with potential to host previously unrecognized gold mineralization. Detailed mapping of the Spring Peak sinter and preserved lithofacies is used to elucidate the locations of high-temperature vent conduits and low temperature, distal-apron fluid pathways, and validates the spatial and temporal relationships of sinter deposition with gold mineralization at depth. Epithermal alteration is most intense along a silicified ridge, which is bounded by NNE striking normal faults and NW striking oblique dextral faults, forming a fertile fault intersection near sinter deposition. The mapping of lithologies, alteration and sinter facies at Spring Peak provides a template for similar studies elsewhere that will actively contribute to exploration targeting in low-sulfidation epithermal systems.
For more information, contact GSN Elko Chapter President, Ajeet Milliard, ajeet@megllc.net

Details

01/16/2025 18:00:0001/16/2025 21:00:00America/Los_AngelesElko Chapter Meeting – Thursday, February 20, 2025

 GSN Elko Chapter Meeting

Thursday, February 20, 2025

Western Folklife Center, 501 Railroad St., Elko, NV

Drinks and Appetizers at 6 pm; Talk at 7 pm

 Speaker: Marcus Angus, Master’s Student, CREG Program and partially funded by GSN Scholarships

Title: Constraining Mineralization and Alteration Through New Geologic Mapping at Spring Peak Low-Sulfidation Epithermal  System, Mineral County, NV

 FOOD & DRINKS SPONSORS: COEUR PRODUCTS

 ABSTRACT:
Marcus J. Angus, Simon Jowitt
Ralph J. Roberts Center for Research in Economic Geology, Department of Geological Sciences and Engineering,     University of Nevada, Reno
Spring Peak is a newly discovered sinter-vein system in Mineral County, NV with a well-preserved epithermal footprint at surface and is being actively explored by Headwater Gold, Inc. The Spring Peak system is hosted within a region constructed of Mesozoic metavolcanics and metasediments, Cretaceous granitic rocks related to satellite plutons of the Sierra Nevada batholith, Miocene subduction-related volcanics and associated volcaniclastics, and Late Pliocene-Pleistocene volcanic centers. The age of mineralization at Spring Peak has yet to be constrained and pending 40Ar/39Ar dating of adularia in mineralized drill core, coupled with rhyolite domes collected at surface, will determine whether Spring Peak has similar Miocene mineralization analogous to the nearby Aurora Mining District, or if Spring Peak is a potentially younger sinter-vein system. High-grade gold mineralization (>15g/t) occurs on property within boiling horizons of structurally controlled hydrothermal upwelling zones. One of these upwelling zones lies directly beneath the outcropping sinter, where high-temperature sinter lithofacies (geyserite) overlies adularia altered and silicified volcanic epiclastic sediments. Sinters are surficial expressions of low-sulfidation epithermal systems and form where silica oversaturated alkali-chloride fluids are expelled in hot spring deposits, forming a predictable gradient in lithofacies with distance from the vent source. New geologic mapping at Spring Peak aims to describe lithology, trends in alteration, and identify favorable structural controls in order to delineate additional upwelling zones with potential to host previously unrecognized gold mineralization. Detailed mapping of the Spring Peak sinter and preserved lithofacies is used to elucidate the locations of high-temperature vent conduits and low temperature, distal-apron fluid pathways, and validates the spatial and temporal relationships of sinter deposition with gold mineralization at depth. Epithermal alteration is most intense along a silicified ridge, which is bounded by NNE striking normal faults and NW striking oblique dextral faults, forming a fertile fault intersection near sinter deposition. The mapping of lithologies, alteration and sinter facies at Spring Peak provides a template for similar studies elsewhere that will actively contribute to exploration targeting in low-sulfidation epithermal systems.
For more information, contact GSN Elko Chapter President, Ajeet Milliard, ajeet@megllc.net
Reno, NV
Event StartsEvent Ends
01/16/202501/16/2025
All Day Event
6:00pm9:00pm