Engineering-Geologic Map of the Eagle A-2 Quadrangle, Fortymile mining district, Alaska
Dates
Publication Date
2001-05
Start Date
1999
End Date
2001
File Modification Date
2014-05-22 11:36:00
Citation
Pinney, D.S., 200105, Engineering-Geologic Map of the Eagle A-2 Quadrangle, Fortymile mining district, Alaska: State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (DGGS), http://dx.doi.org/10.14509/2672.
Summary
The Alaska Division of Geological & Geophysical Surveys (DGGS) has conducted 1:63,360-scale geologic mapping of the Eagle A-2 Quadrangle (270 square miles; equivalent to four 7.5-minute quadrangles). The area is part of the 100-year old Fortymile mining district and is located in eastern Alaska near the Alaska-Yukon border. This map illustrates potential near-surface sources of various geologic materials that may be useful for construction. Field observations indicate that each geologic unit (for example, stream alluvium) has a definite composition or range of composition. Therefore, the probable presence of materials is interpreted from the distribution of geologic units on the geologic map of this quadrangle. This map is generalized [...]
Summary
The Alaska Division of Geological & Geophysical Surveys (DGGS) has conducted 1:63,360-scale geologic mapping of the Eagle A-2 Quadrangle (270 square miles; equivalent to four 7.5-minute quadrangles). The area is part of the 100-year old Fortymile mining district and is located in eastern Alaska near the Alaska-Yukon border. This map illustrates potential near-surface sources of various geologic materials that may be useful for construction. Field observations indicate that each geologic unit (for example, stream alluvium) has a definite composition or range of composition. Therefore, the probable presence of materials is interpreted from the distribution of geologic units on the geologic map of this quadrangle. This map is generalized and is not intended to show exact locations of specific materials. Local variations are common, especially near unit boundaries. The map was derived electronically from the geologic map of the area using Geographic Information System (GIS) software. It is locally verified by ground observations during field visits. The results should be considered reconnaissance in nature.
This project, resulting map, geospatial data are intended to provide a geologic map and a geologic interpretation of the Fortymile mining district at 1:63,360 scale. Previous published 1:63,360 scale geologic maps of this area have been reconnaissance-level maps or only covered portions of the quadrangle. Mapping at 1:63,360 scale (or more detailed) is needed to identify critical geologic features that may relate to more regional structures or geologic units. These detailed observations are also critical to test or use in tectonic models. This map also provides a geologic base in which to interpret geochemical results from the concurrent DGGS rock sampling program.