Lower Paleozoic and Proterozoic rocks of Southern Brooks Range, Alaska
Conference
·
· Am. Assoc. Pet. Geol., Bull.; (United States)
OSTI ID:6461606
Lower Paleozoic or Proterozoic basement rocks occur in windows and thrust plates in several areas of the Brooks Range. Uranium-lead radiometric analyses of highly metamorphosed rocks from the Baird Mountains and Ernie Lake area have yielded Proterozoic ages. Structural, stratigraphic, petrologic, and isotopic evidence exists for Proterozoic(.) rocks in the schist belt; around the Chandalar, Arrigetch,and Igikpak plutons; and in the Cosmos Hills window. Fossiliferous, Lower Paleozoic, low-grade metasedimentary rocks occur in the Romanzof Mountains, Doonerak window, and Baird Mountains, and may also surround the Chandalar plutons. Locally, the Lower Paleozoic rocks are unconformably overlain by Devonian to Mississippian metasediments and may stratigraphically overlie older, higher grade metamorphic rocks. Similarities in the stratigraphic settings and lithologies and in fossil ages and affinities allow correlation of the Lower Paleozoic rocks in the southern Brooks Range. Correlation of Lower Paleozoic rocks exposed beneath the Endicott allochthon at the Doonerak fenster with coeval rocks in an overlying thrust plate to the south at Snowsden Mountain is especially significant. A west-trending thrust fault, which is rooted in Lower Paleozoic basement, along the north side of Snowsden Mountain is postulated to account for these relationships. Apparently, the Endicott allochthon roots beneath the Snowsden Mountain thrust fault. Evidence form conodont samples currently being studied by A. Harris may bear on the extent of the Lower Paleozoic rocks in the upper plate of the Snowsden Mountain thrust and in the Chandalar area.
- Research Organization:
- Alaska Div. Geological and Geographical Surveys, Fairbanks
- OSTI ID:
- 6461606
- Report Number(s):
- CONF-8505215-
- Conference Information:
- Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Journal Volume: 69:4
- Country of Publication:
- United States
- Language:
- English
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·
OSTI ID:5014504
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·
Sun Mar 31 23:00:00 EST 1985
· Am. Assoc. Pet. Geol., Bull.; (United States)
·
OSTI ID:5961740
Facies comparison of autochthonous and allochthonous Permian and Triassic units, north-central Brooks Range, Alaska
Conference
·
Sun Mar 31 23:00:00 EST 1985
· Am. Assoc. Pet. Geol., Bull.; (United States)
·
OSTI ID:6319203