Skip to main content

Person

Michael A Cosca

Research Geologist
Email: mcosca@usgs.gov
Office Phone: 303-236-4974
ORCID: 0000-0002-0600-7663

Location
P.O. Box 25585
Denver Federal Center
Lakewood , CO 80225-0585
US
thumbnail
Ar/Ar data are reported from minerals and rocks that were collected as part of a mineral resource investigation of the Tonopah, Divide, and Goldfield districts in Nevada. Data are reported from 92 samples and associated standards from eight separate neutron irradiations in the Denver USGS TRIGA reactor, including separated mineral grains and whole rocks. Data were collected by infrared laser heating of irradiated samples, either incremental heating or fusion, and analysis by multi-collector mass spectrometry. The reported data have been corrected for blanks, radioactive decay, and interfering nucleogenic reactions associated with sample irradiation.
thumbnail
These data are U-Pb sensitive high-resolution ion microprobe (SHRIMP) geochronology data from quartz porphyry dikes for the study of the Butte mining district, U.S.A. Results of the study are described and interpreted in Lund and others (2018).
thumbnail
This dataset accompanies the planned publication “Mantle Melting in Regions of Thick Continental Lithosphere-Examples from Late Cretaceous and Younger Volcanic Rocks, Southern Rocky Mountains, Colorado” in the journal Geosphere. The dataset includes 40Ar/39Ar data for 19 samples from the Rabbit Ears volcanic field and from the Elkhead Mountains in northcentral Colorado, USA. Samples were collected from this area by James Mize (University of Colorado, Boulder), Lang Farmer (University of Colorado, Boulder), and Michael Cosca (USGS) with helpful input about sampling locations by Kenzie Turner (USGS). The samples were analyzed in the Denver Argon Geochronology Laboratory at the USGS from September, 2013 to July, 2017.
thumbnail
Ar/Ar data are reported from eight samples of white mica separated from rock samples collected along the Austroalpine-Pennine boundary in the Central Alps of Switzerland. These samples were collected as part of a Caltech PhD study to examine the tectonic history of this boundary and these argon geochronology data represent one small part of the study. Data are reported from these eight samples together with standards that were irradiated together in the Denver USGS TRIGA reactor. Data from the samples were collected by incremental infrared laser heating of individual grains and analysis by multi-collector mass spectrometry. The reported data have been corrected for blanks, radioactive decay, and interfering nucleogenic...
thumbnail
Backscatter electron (BSE) and panchromatic cathodoluminescent (CL) imagery of minerals from samples dated by 40Ar/39Ar are for the study of the Butte mining district, U.S.A. Results of the study are described and interpreted in Lund and others (2018).These data are shared to meet open data requirements.
View more...
ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact sciencebase@usgs.gov.