Unnamed Occurrence (ARDF - EA081; in headwaters of Nugget Gulch), Southeast Fairbanks Census Area, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - EA081; in headwaters of Nugget Gulch)	- not defined -
Southeast Fairbanks Census Area	Census Area
Alaska	State
USA	Country

This occurrence is located within Doyon, Ltd. selected or conveyed land. For more information contact Doyon, Ltd., Fairbanks, Alaska.
Location: This occurrence is located at the hig point of the ridge between Nugget Gulch and the western branch of Sam Patch Creek. The coordinates are the approximate center of the occurrence,on the boundary between sections 10 and 11, T. 7 S., R. 33 E., of the Fairbanks Meridian; the location is only accurate within 1 mile. This occurrence is located within Doyon, Ltd. selected or conveyed land.
Geology: The rocks in the vicinty of this occurrence include Paleozoic quartz-mica-chlorite schist that is locally silicified and hornfelsed and Mesozoic or Paleozoic pyroxenite and hornblendite (Foster, 1976; DiMarchi, 1993). These rocks have been intruded by Tertiary or Mesozoic granitic rocks. Stream-sediment samples collected by WGM Inc. from the creeks draining the divide between Sam Patch Creek and Nugget Gulch contain between 25 and 32 ppb gold (DiMarchi, 1993). An anomalous soil sample with 85 ppb gold and a stream-sediment sample containing 1,081 ppb gold were collected by ASA Inc. Restricted zones of silicification and quartz-carbonate alteration are present, and pyrite is found in quartz veins and disseminated within folded layers of quartzite. There is abundant iron-oxide-stained soil with fragments of quartz-carbonate veining on ridge tops in the area, but without associated gold anomalies. There is a strong magnetic anomaly in the area of the 1,081-ppb gold sample, indicating the presence of a large, east-west-trending ultramafic body (WGM Inc., 1998 [DLR 98-12]). Two deposit models have been proposed for this occurrence. Copper-bearing calc-silicate rocks in the area suggest the potential for copper-gold skarns (DiMarchi, 1993). The presence of ultramafic rocks suggest the potential for Mother Lode-style, gold-quartz-carbonate vein mineralization (WGM Inc., 1998 [DLR 98-12]). Stream -ediment samples were collected by WGM Inc. in 1990, from the creeks draining the divide between Sam Patch Creek and Nugget Gulch (DiMarchi, 1993). ASA Inc. collected stream and soil samples in the area in 1992. A geophysical survey was flown in the Nugget Gulch area in 1997 (WGM Inc., 1998 [DLR 98-12]).
Workings: Stream-sediment samples were collected by WGM Inc. in 1990, from the creeks draining the divide between Sam Patch Creek and Nugget Gulch (DiMarchi, 1993). ASA Inc. collected stream and soil samples in the area in 1992. A geophysical survey was flown in the Nugget Gulch area in 1997 (WGM Inc., 1998 [DLR 98-12]).
Age: Paleozoic or younger.
Alteration: There are restricted zones of silicification and quartz-carbonate alteration in the vicinity of this occurrence at the head of Nugget Gulch (DiMarchi, 1993).

Commodities (Major) - Au; (Minor) - Cu
Development Status: None

Other Databases

Link to USGS - Alaska:	EA081

Other Regions, Features and Areas containing this locality

References