Filters: Tags: Volcanic Arc (X) > partyWithName: Benowitz, J.A. (X)

Filters Date Range Past year (0) Past month (0) Past week (0) Past day (0) Custom range... To   Search Contacts Alaska Division of Geological & Geophysical Surveys Layer, P.W. Wypych, Alicja Freeman, L.K. Twelker, Evan Tag Types Theme (2) Place (2) Tag Schemes Alaska Division of Geological & Geophysical Surveys (2) ISO 19115 Topic Category (2) View Results as: JSON ATOM CSV

40Ar/39Ar data from the Talkeetna Mountains C-4 Quadrangle and adjoining areas, central Alaska This report presents 40Ar/39Ar step-heating geochronology results for igneous and metamorphic rocks from the Alaska Division of Geological & Geophysical Surveys' (DGGS) Talkeetna Mountains C-4 Quadrangle and Adjoining Areas geologic mapping project. Hornblende-bearing gabbro returned a Late Triassic crystallization age consistent with regional results for Nikolai Greenstone-related magmatism. We determined Early Jurassic metamorphic ages for hornblende and sericite from two samples of upper greenschist to amphibolite grade metavolcanic rocks. Our results indicate that a granodiorite pluton intruding Wrangellia in the study area has a Middle Jurassic age consistent with the Talkeetna Arc, indicating that the Wrangellia... Tags: 40Ar/39Ar, Age Dates, Analyses, Analyses and Sampling, Analytical Lab Results, All tags... Analytical Results, Ar-Ar, Bedrock, Bedrock Geology, Geochronology, Geology, Lab Methods, Plutonic Rocks, Plutons, STATEMAP Project, Sample Location, Strategic and Critical Minerals Assessment Project, Talkeetna Mountains Quadrangle, Volcanic, Volcanic Arc, Volcanic Rocks, geoscientificInformation, Fewer tags 40Ar/39Ar ages of rocks collected from the Passage Canal area, Seward D-7 Quadrangle, Alaska This report presents 40Ar/39Ar step-heating geochronology results from a single outcrop of a mineralized near-trench intrusion exposed in a road cut near Whittier, Alaska. The outcrop is the best road-accessible occurrence of a Tertiary near-trench pluton in the region and is commonly visited by field trips, yet no prior geochronological data from this outcrop have been published. Two chronologically distinct intrusive bodies, the Paleogene Sanak-Baranof belt and the Eshamy-suite, are documented in the upper Cook Inlet area. Geochronological analysis of the two samples described in this report confirms that the Whittier road-cut intrusion and veins are coeval (53.0 +/- 0.3 Ma and 50.9 +/- 0.2 Ma, respectively) with... Tags: 40Ar/39Ar, Age Dates, Analyses, Analyses and Sampling, Analytical Lab Results, All tags... Analytical Results, Ar-Ar, Bedrock, Bedrock Geology, Geochronology, Geologic, Geology, Igneous, Igneous Rocks, Isotopes, Lab Methods, Methods, Mineralogy, Rocks, Sample Location, Seward Quadrangle, Volcanic Arc, Volcanic Rocks, Whittier, geoscientificInformation, Fewer tags