Distribution, facies, ages, and proposed tectonic associations of regionally metamorphosed rocks in Southwestern Alaska and the Alaska Peninsula
The oldest dated metamorphic sequence in Alaska, the fault-bounded Kilbuck Terrane, consists of continental rocks that were metamorphosed under amphibolite-facies conditions during early Proterozoic (1.77 Ga) time. Proterozoic or early Paleozoic metamorphic ages are also possible for greenschist- and amphibolite-facies continental rocks in interior Alaska (Ruby and Nixon Fork terranes). Medium-grade metamorphism on the Alaska Peninsula accompanied intrusion of a Jurassic arc. North of Bristol Bay, low-grade, locally high-pressure Mesozoic metamorphism is attributed to the progressive underthrusting of a subduction complex beneath an oceanic arc followed by underthrusting of the Kilbuck Terrane beneath the subduction complex.
Citation Information
Publication Year | 1996 |
---|---|
Title | Distribution, facies, ages, and proposed tectonic associations of regionally metamorphosed rocks in Southwestern Alaska and the Alaska Peninsula |
DOI | 10.3133/pp1497B |
Authors | Cynthia Dusel-Bacon, Elizabeth O. Doyle, Stephen E. Box |
Publication Type | Report |
Publication Subtype | USGS Numbered Series |
Series Title | Professional Paper |
Series Number | 1497 |
Index ID | pp1497B |
Record Source | USGS Publications Warehouse |
Related Content
Upper Midwest Water Science Center - Madison, WI, Office
1 Gifford Pinchot Drive
Madison, WI 53726
United States
Cynthia Dusel-Bacon
Scientist Emeritus
Stephen Box
Scientist Emeritus
Related Content
Upper Midwest Water Science Center - Madison, WI, Office
1 Gifford Pinchot Drive
Madison, WI 53726
United States