Description

Location: Western Folklife Center, Elko NV

Contact: justin.b.milliard@gmail.com

The Elko GSN Chapter is excited to have Dylan Baldwin of Kinross Gold giving the first presentation of the fall season on Round Mountain.  McGinley and Associates is generously sponsoring the meeting.

LOCATION:  Western Folk Life Center, 501 Railroad St., Elko, NV

DATE:  Thursday, September 15th          

TIME:  Food and drinks @ 6 pm and talk to begin at 7 pm.

TITLE:  Progressive evolution from distributed to compartmentalized fluid flow: a refined model of formation for the Round Mountain, NV low-sulfidation epithermal Au-Ag deposit

PRESENTER:  Dylan Baldwin, Exploration Manager, Round Mountain Gold Corp, Kinross Gold

Abstract: 

The Round Mountain deposit is an epigenetic low-sulfidation epithermal (LSE) Au-Ag system hosted by, and genetically related to, volcanic and sub-volcanic units of the Oligocene-age Toquima Caldera complex.  The complex lies within the Western Nevada Volcanic Field, a rhyolitic volcanic province formed at the culmination of “ignimbrite flareup” volcanism associated with SW-younging slab rollback of the Farallon plate during the Eocene-Miocene period. The deposit is a massive arcuate veinlet and disseminated orebody with a WNW-elongate arcuate footprint of > 3 x 1.8 km which formed around 26.3 Ma, less than a million years after eruption of the host rock sequence.  Aside from a small exposure of sinter atop Round Mountain hill, which stood over 150m above the pediment gravels covering the main deposit, the upper portions of the system were eroded prior to discovery, leading to formation of large placer Au deposits.  Recent mining and drilling in the western pit area, in the hanging wall of down-to-the-west Basin and Range normal faults, has for the first time allowed a full top to bottom exposure of the mineral system, and improved understanding of the deposit.

In many ways, Round Mountain has typical characteristics of LS epithermal deposits – mineralization occurs within 600m of the paleo water table; fluid inclusions and vein/alteration mineral assemblages indicate temperatures <300 °C, and low-salinity, near-neutral pH fluids; and there is evidence for vein/fault surface interaction.  The exceptional characteristics of the deposit, specifically the immense tonnage of “true” disseminated mineralization, the geometry and continuity of bonanza veins, and the vertical interval of economic mineralization, are the result of a unique combination of stratigraphy, structure, and sources.  YE 2021 proven and probable reserves at Round Mountain are 3.037 Moz Au, and exploration continues to add to the endowment of this world-class orebody, which has produced >16 Moz Au to date.

 

Details

09/15/2022 18:00:0009/15/2022 21:00:00America/Los_AngelesGSN Elko Chapter MeetingThe Elko GSN Chapter is excited to have Dylan Baldwin of Kinross Gold giving the first presentation of the fall season on Round Mountain.  McGinley and Associates is generously sponsoring the meeting. LOCATION:  Western Folk Life Center, 501 Railroad St., Elko, NV DATE:  Thursday, September 15th           TIME:  Food and drinks @ 6 pm and talk to begin at 7 pm. TITLE:  Progressive evolution from distributed to compartmentalized fluid flow: a refined model of formation for the Round Mountain, NV low-sulfidation epithermal Au-Ag deposit PRESENTER:  Dylan Baldwin, Exploration Manager, Round Mountain Gold Corp, Kinross Gold Abstract:  The Round Mountain deposit is an epigenetic low-sulfidation epithermal (LSE) Au-Ag system hosted by, and genetically related to, volcanic and sub-volcanic units of the Oligocene-age Toquima Caldera complex.  The complex lies within the Western Nevada Volcanic Field, a rhyolitic volcanic province formed at the culmination of “ignimbrite flareup” volcanism associated with SW-younging slab rollback of the Farallon plate during the Eocene-Miocene period. The deposit is a massive arcuate veinlet and disseminated orebody with a WNW-elongate arcuate footprint of > 3 x 1.8 km which formed around 26.3 Ma, less than a million years after eruption of the host rock sequence.  Aside from a small exposure of sinter atop Round Mountain hill, which stood over 150m above the pediment gravels covering the main deposit, the upper portions of the system were eroded prior to discovery, leading to formation of large placer Au deposits.  Recent mining and drilling in the western pit area, in the hanging wall of down-to-the-west Basin and Range normal faults, has for the first time allowed a full top to bottom exposure of the mineral system, and improved understanding of the deposit. In many ways, Round Mountain has typical characteristics of LS epithermal deposits - mineralization occurs within 600m of the paleo water table; fluid inclusions and vein/alteration mineral assemblages indicate temperatures <300 °C, and low-salinity, near-neutral pH fluids; and there is evidence for vein/fault surface interaction.  The exceptional characteristics of the deposit, specifically the immense tonnage of “true” disseminated mineralization, the geometry and continuity of bonanza veins, and the vertical interval of economic mineralization, are the result of a unique combination of stratigraphy, structure, and sources.  YE 2021 proven and probable reserves at Round Mountain are 3.037 Moz Au, and exploration continues to add to the endowment of this world-class orebody, which has produced >16 Moz Au to date.  Reno, NV
Event StartsEvent Ends
09/15/202209/15/2022
All Day Event
6:00pm9:00pm