Energy, Mines and Resources

Yukon Geological Survey - Home

Bedrock Geology

| About YGS | YGS News | Site Map |

Rackla Belt

| Magmatism along Dawson Fault | Frances Lake | Tay River | Coast Belt | Rackla Belt | Hyland | North Yukon | Yukon Bedrock Geology Map |

Project Leaders: David Moynihan (2013-); Maurice Colpron (2011-2012)

The E-W-trending Rackla belt of east-central Yukon is currently the focus of intensive exploration following the recent discovery of Carlin-style gold mineralization in the area. This area includes the eastern part of the Dawson thrust, a major, multiply-reactivated structure that marks the northern boundary of Selwyn basin.
In 2012, YGS completed mapping of five contiguous 1:50,000 sheets along the belt, including the area that hosts the Osiris, Conrad, Anubis and Pharaoh gold occurrences (ATAC resources Ltd.). In 2013, the mapped area was extended eastward to include the eastern end of the Dawson thrust (NTS 106B/04). Fieldwork for the project was completed during the summer of 2014 and updates will be presented in a new compilation map of the eastern Rackla belt in early 2015.

In addition to bedrock mapping, YGS is undertaking analytical studies to further constrain the stratigraphy and mineralization potential of the belt.
• Provenance analysis (using detrital zircon; with Jim Crowley, Boise State University)
• Litho- and chemo-stratigraphy of Neoproterozoic rocks (using C-isotopes and measured sections; with Justin Strauss, Harvard University)


  • Chakungal, J., and Bennett, V., 2011, New bedrock geology of Mount Mervyn map sheet (106C/04) and mineral potential for the South Wernecke mapping project, in MacFarlane, K.E., Weston, L.H., and Relf, C., eds., Yukon Exploration and Geology 2010, Yukon Geological Survey, p. 55-87.
  • Colpron, M., 2012. Preliminary geological map of the Mount Ferrell area (106C/3), central Yukon. Yukon Geological Survey, 2012-11, 1:50,000.
  • Colpron, M., 2012. Preliminary observations on the geology of the Rackla belt, Mount Ferrell map area (NTS 106C/3), central Yukon. In: Yukon Exploration and Geology 2011, K.E. MacFarlane and P.J. Sack (eds.), Yukon Geological Survey, p. 27-43.
  • Colpron, M., Moynihan, D., Israel, S., and Abbott, G., 2013. Geological map of the Rackla belt, east-central Yukon (NTS 106C/1-4, 106D/1). Yukon Geological Survey, Energy, Mines and Resources, Government of Yukon, Open File 2013-13.
  • Moynihan, D., 2014. Geological map of NTS 106B/04, east-central Yukon. Yukon Geological Survey, 2014-1, 1:50,000.
  • Moynihan, D., 2014. Bedrock Geology of NTS 106B/04, eastern Rackla belt. In: Yukon Exploration and Geology 2013, K.E. McFarlane and M. Nordling (eds.), Yukon Geological Survey, p. 147-167.