Source: https://minerals.usgs.gov/science/yukon-tanana-upland-studies/index.html
Timestamp: 2019-04-22 11:23:13+00:00

Document:
Half-meter-thick quartz veins cut across outcrops of granitic gneiss on Divide Mountain along the Alaska-Yukon border, August 2015. Photo by J. Jones III, USGS.
The Yukon-Tanana terrane, stretching from eastern Alaska to northern British Columbia, is a geologically complex block containing deposits of base-metal, platinum-group-element, and gold-silver-copper mineralization. However, geologic and exploration models for these deposits are limited by a lack of data regarding the individual deposits, their tectonic settings, and the genetic processes critical to their formation. Unraveling the history of this terrane is essential for assessing the extent and distribution of that mineralization and for understanding the geologic factors controlling deposit formation. This project brings together scientists from both sides of the Alaska-Canada border to develop a coherent model for the geologic evolution of the Yukon-Tanana block and provide a much-needed context for more focused studies and mineral exploration within the terrane.
This project builds on the work of a previous investigation, Alaska/Yukon Geophysical/Geological Reconciliation of the Pericratonic Yukon-Tanana Terrane, which focused on reconciling the various interpretations in mapping of geologic and geophysical trends across the Alaska-Yukon border. Geophysical features maps were developed to allow for the delineation of subsurface features, structures, and domains across the Alaska/Yukon border. These maps then served as a platform for a cross-border regional synthesis which integrated geologic mapping, geophysical data, structural analyses, geochemistry, and age-dating analyses.
Helicopter landing to pick up field personnel after a day of geologic mapping and sampling in the Fortymile region north of Tok, Alaska. Photo by J. Jones III, USGS.
Geologic framework studies will focus on the characterization of rocks exposed in the Tanacross quadrangle of eastern Alaska and in surrounding regions. Research will include igneous, metamorphic, structural, and thermochronologic studies. In addition to new field mapping and sampling, selected legacy samples in the USGS rock archive will be re-analyzed. These investigations will allow the researcher to highlight the geology and structures favorable for permissive metallic-mineral-resource discovery.
Geophysical framework studies will combine existing regional data with new airborne geophysical data that spans the international border. Preliminary results will be refined and tested with new geologic mapping and observation. Geophysical interpretations will be compared to known mineral occurrences and will aid in understanding the controls and loci of metallogenetic events and their association with metamorphic and magmatic events.
Metallogenic framework studies will focus on mineral occurrences and deposits in the study area and how they compare to deposits in districts both east (Klondike-White Gold, Yukon) and west (Fairbanks, Alaska). Gold resource tracts in east-central Alaska will be delineated, and gold deposit types will be defined. Detailed studies of known lodes on both sides of the Alaska-Yukon border will be combined with placer fingerprint studies in an attempt to relate placer accumulations to specific lodes based on the physical and chemical features of the gold in both occurrences.
Publish reports that will contribute to clarifying the regional geologic framework of east-central Alaska by summarizing previous research on the Mesozoic and Cenozoic geologic history of the region.
Previous activities in the area focused on geophysical mapping, geophysical and geological integration, and integrated interpretation by using new geophysical maps to facilitate cross-border geologic mapping, key units, assemblages, and structures that are present on both sides of the Alaska-Yukon border. USGS scientists worked together with the Alaska Division of Geological and Geophysical Surveys, the Yukon Geological Survey, and the Geological Survey of Canada to reconcile their differing perspectives on the geologic and geophysical data into a coherent model for the geologic evolution of the Yukon-Tanana block.
USGS scientist examining outcrops of strongly deformed and metamorphosed rock along Divide Mountain in the Yukon-Tanana upland of eastern Alaska. Photo by J. Jones III, Alaska.
USGS scientist digging through tundra in hopes of finding bedrock to sample for geochemistry and geochronology, Yukon-Tanana upland, eastern Alaska. Photo by J. Jones III, USGS.
Cynthia Dusel-Bacon, C.R. Bacon, P.B. O'Sullivan, and W.C. Day, 2016, Canadian Journal of Earth Sciences, 53(3), p. 260-280, doi:10.1139/cjes-2015-0138.
W. Miles, R.W. Saltus, N. Hayward, and D. Oneschuk, 2015, Geological Survey of Canada Open-File 7862, scale 1:1,120,000, 1 sheet, doi:10.4095/296589.
C. Dusel-Bacon, J.N. Aleinikoff, W.C. Day, and J.K. Mortensen, 2015, Geosphere, 11(3), p. 786-822, doi:10.1130/GES01092.1.
C.R. Bacon, C. Dusel-Bacon, J.N. Aleinikoff, and J.F. Slack, 2014, Geosphere, v. 10, p. 1432-1455, doi:10.1130/GES01037.1.
W.C. Day, J.M. O’Neill, C. Dusel-Bacon, J.N. Aleinikoff, and C.R. Siron, C.R., 2014, U.S. Geological Survey Scientific Investigations Map 3291, scale 1:63,360, https://doi.org/10.3133/sim3291.
R.W. Saltus, 2013, Earth Magazine, 58(10), p. 8–9, https://www.earthmagazine.org/article/tackling-boundary-faults-across-alaska-yukon-border-report-field.
C. Dusel-Bacon, W.C. Day, and J.N. Aleinikoff, 2013, Canadian Journal of Earth Sciences, 50(8), p. 826-846, doi:10.1139/cjes-2013-0004.
High terraces along the Fortymile River: Transient bedrock incision from river capture?
A.B. Bender and R.O. Lease, 2016, Alaska Miners Association 2016 Annual Meeting, November 6-10, 2016, Anchorage, AK.
J.S. Caine, 2016, Geological Society of America Abstracts with Programs, Vol. 48, No. 7, doi:10.1130/abs/2016AM-284462.
W.R. Weisberg, E.E. Marsh, H.A. Lowers, and D.T. Adams, 2016, Geological Society of America Abstracts with Programs, Vol. 48, No. 7, doi:10.1130/abs/2016AM-286190.
R.D. Taylor, H.A. Lowers, R.J. Goldfarb, and E.E. Marsh, 2016, 35th International Geological Congress, 27 August - 4 September, 2016, Cape Town, South Africa. View Taylor IGC abstract.
J.V. Jones III, C.S. Holm-Denoma, and P.B. O'Sullivan, 2015, Geological Society of America Abstracts with Programs, v. 47, no. 7, p. 860. View Jones 2015 GSA abstract 1.
J.V. Jones III, Dawson Rocks Conference, August 2015, Dawson City, YT, Canada.
J.S. Caine, S.A. Israel, D.C. Murphy, and J. Benowitz, 2015, Geological Society of America Abstracts with Programs, v. 47, no. 4, p. 51. View Caine 2015 GSA abstract.
J.V. Jones III, J.S. Caine, C.S. Holm-Denoma, R.O. Lease, R.W. Saltus, and E. Todd, 2015, Geological Society of America Abstracts with Programs, v. 47, no. 4, p. 18. View Jones 2015 GSA abstract 2.
R.W. Saltus, D.C. Murphy, N. Hayward, J.V. Jones III, J.S. Caine, and M. Colpron, 2015, Geological Society of America Abstracts with Programs, v. 47, no. 4, p. 17. View Saltus 2015 GSA abstract.
J.V. Jones III, J.S. Caine, C.S. Holm-Denoma, R.O. Lease, and E. Todd, 2014, Alaska Miners Association 2014 Annual Meeting, November 3-9, 2014, Anchorage, AK.
J.S. Caine, D.C. Murphy, and S.A. Israel, 2013, Geological Society of America Abstracts with Programs, Vol. 46, No. 6, p. 28. View Caine 2014 GSA abstract.
C. Dusel-Bacon, P.B. O'Sullivan, W.C. day, and C.R. Bacon, 2013, Geological Society of America Abstracts with Programs, Vol. 46, No. 6, p. 794. View Dusel-Bacon 2014 GSA abstract.
J.K. Mortensen and C. Dusel-Bacon, 2014, Geological Society of America Abstracts with Programs. Vol. 46, No. 6, p. 794. View Mortensen 2014 GSA abstract.
J.S. Caine, S.A. Israel, K.R. Sicard, and C.P. Hults, 2013, Geological Society of America Abstracts with Programs, v. 45, no. 7, p. 78. View Caine 2013 GSA abstract.
C. Dusel-Bacon, J.N. Aleinikoff, W.C. Day, and J.K. Mortensen, 2013, Geological Society of America Abstracts with Programs, v. 45, no. 7, p. 78. View Dusel-Bacon 2013 GSA abstract.
R.W. Saltus, N. Hayward, J.V. Jones III, and D.C. Murphy, 2013, Geological Society of America Abstracts with Programs, v. 45, no. 7, p. 78. View Saltus 2013 GSA abstract.
You are not running scripts - tabs may not collapse in mobile view.

References: v. 
 v. 
 v. 
 v. 
 v. 
 v. 
 v. 
 v.