| Quadrangle map, 1:250,000-scale | CY |
|---|---|
| Quadrangle map, 1:63,360-scale | B-5 |
| Latitude | 65.304 |
| Longitude | -143.289 |
| Nearby scientific data | Find additional scientific data near this location |
| Location and accuracy | The Woodchopper Creek basin and the area surrounding it cover approximately 55 square miles. Tributaries to Woodchopper Creek include Dome Creek (CY010), Mineral Creek (CY020), Moore Creek (CY016), and Iron Creek (CY019). The coordinates for the Woodchopper Creek mine are located in the center of the placer workings marked on the Charley River (B-5) quadrangle topographic map, in section 34, T. 6 N., R. 21 E., of the Fairbanks Meridian. The principal placer mining activity was about 1.25 miles upstream and downstream from this point. The location is accurate. |
Geologic descriptionThe headwaters of Woodchopper Creek are underlain by Precambrian to Paleozoic metamorphic rocks that are intruded by Mesozoic(?) granitic plutons. The creek flows across a belt of Cretaceous to Tertiary conglomerate and other sedimentary rocks (Brabb and Churkin, 1969; Dover and Miyaoka, 1988). Gold placers are found in or immediately downstream from this belt. The proximal source of the gold is likely the conglomerate, but the ultimate source is probably the older metamorphic rocks upstream (Prindle and Mertie, 1912). Platinum metals are alloyed with the gold, and monazite is also present. In the 1912 workings, the depth to the conglomerate bedrock was about 22 feet; about 11 feet of this was gravel that contained many granite boulders (Prindle and Mertie, 1912). In 1942, the mean of 6 assays from the creek was 932 parts Au per thousand, and 62 parts Ag per thousand. One sample assayed 0.42 percent Pt with a trace of Ir (Mertie, 1942). Gold was discovered in 1902, or possibly earlier; mining and exploration continued intermittently in the area until 1964. In 1910, the gold output for the area was about $20,000 (1910 dollars) (Cobb, 1973; B 1374). | |
| Geologic map unit | (-143.291396698863, 65.3036648315207) |
|---|---|
| Mineral deposit model | Placer Au (Cox and Singer, 1986; model 39a). |
| Mineral deposit model number | 39a |
| Age of mineralization | Quaternary. |
| Workings or exploration | Gold was discovered in 1902, or possibly earlier, and mining and exploration continued intermittently in the area until 1964, when the dredge that had been operating since 1937 shut down. |
|---|---|
| Indication of production | Yes; medium |
| Production notes | Gold output for 1910 was estimated to be about $19,000 (1910 dollars) for the Woodchopper Creek area. For 1909, gold production was estimated to be about $20,000 (1909 dollars) (Cobb, 1976 [OFR 76-632]). |
Additional commentsSee also Mineral Creek (CY020), Alice Gulch (CY002), Dome Creek (CY010), and Iron Creek (CY019). This site is within the Yukon-Charley Rivers National Preserve. | |