About YGS | Contact Staff | YGS News | Site Map | Links
2. Ancient Pacific Margin NATMAP
The Ancient Pacific Margin NATMAP project is a collaborative effort between the following organizations:
• Geological Survey of Canada (GSC),
• British Columbia Geological Survey Branch (BCGS),
• Yukon Geological Survey (YGS),
• Division of Geological and Geophysical Surveys of the State of Alaska (DGGS), and the
•U.S. Geological Survey (USGS).
Map of Yukon-Tanana Terrane with displacement along Tintina Fault restored to pre-Cretaceous locations.
This project aims to elucidate the stratigraphic and tectonic framework of the belt of rocks which lies between ancestral North America and the oceanic/accreted terranes to the west – the pericratonic terranes. An ancillary goal of the project is to characterize the metallogenic potential of the pericratonic terranes. These goals are primarily addressed through regional bedrock mapping projects which span the distribution of pericratonic rocks in western Canada and eastern Alaska. Bedrock mapping is complemented by geochronological, geochemical, paleontological, geophysical, and metallogenic studies. Mapping projects in northern British Columbia, Yukon and eastern Alaska constitute the northern component of the Ancient Pacific Margin NATMAP project.
Northern Component
The Yukon-Tanana Terrane of Yukon, Alaska and northern British Columbia consists of lithologically diverse successions of metasedimentary and metavolcanic rocks and voluminous mid- and late Paleozoic granitic metaplutonic bodies. Significant volcanogenic massive sulphide deposits have been discovered in Yukon-Tanana Terrane, particularly in the Delta and Bonnifield districts in Alaska and in the Finlayson Lake belt in southeastern Yukon, and the potential for further discoveries is considered to be high. However, exploration for new deposits has been hindered by the paucity of stratigraphic syntheses from the terrane as a whole. One of the goals of the Ancient Pacific Margin NATMAP project is to address the deficiencies in stratigraphic information from the Yukon-Tanana Terrane.
Since inception of the project in 1999, members of the northern component of the Ancient Pacific Margin NATMAP (the Yukon-Tanana Working Group) have made great progress in understanding Yukon-Tanana Terrane. Sufficient geological mapping and uranium-lead dating have now been completed in order to construct composite stratigraphic sections for areas along the extent of southeastern Yukon-Tanana Terrane and to provide preliminary correlations between the various mapping projects. Yearly updates of these progresses appear as joint publications in Yukon Exploration and Geology (YGP) and Geological Fieldwork (BCGS). These data are also being compiled on a common base (with the Tintina Fault restored) with the objective of constructing a set of paleogeographic maps for Yukon-Tanana Terrane. These maps will identify what geological environments were operative at different times in the evolution of the terrane and highlight areas where information is lacking. Different types of mineral deposits are associated with different geological environments so predictive depositional models developed by the Yukon-Tanana Working Group will help to focus future exploration.
Yukon-Tanana Working Group
Maurice Colpron (YGS)
Cynthia Dusel-Bacon (USGS)
Richard Friedman (University of British Columbia)
Steve Gordey (GSC)
Mitch Mihalynuk (BCGS)
Jim Mortensen (University of British Columbia)
Don Murphy (YGS)
JoAnne Nelson (BCGS)
Rainer Newberry (University of Alaska – Fairbanks)
Steve Piercey (University of British Columbia)
Charlie Roots (GSC-YGS)
Jim Ryan (GSC)
Dave Szumigala (DGGS)
Mike Villeneuve (GSC)
Melanie Werdon (DGGS)