Skip to main content
U.S. flag

An official website of the United States government


Data intro.

Photoluminescence Imaging of Whole Zircon Grains on a Petrographic Microscope - An Underused Aide for Geochronologic Studies

The refractory nature of zircon to temperature and pressure allows even a single zircon grain to preserve a rich history of magmatic, metamorphic, and hydrothermal processes. Isotopic dating of micro-domains exposed in cross-sections of zircon grains allows us to interrogate this history. Unfortunately, our ability to select the zircon grains in a heavy mineral concentrate that records the most ge

Electron microprobe analyses of feldspars and petrographic, geochemical, and geochronologic data from the Hawkeye Granite Gneiss and Lyon Mountain Granite Gneiss in the Adirondacks of New York (ver. 2.0, May 2023)

Iron oxide-apatite (IOA) deposits of the Adirondack Mountains of New York locally contain elevated rare earth element (REE) concentrations (e.g. Taylor and others, 2019). Critical to evaluating resource potential is understanding the genesis of the IOA deposits that host the REE-rich minerals. As part of this effort, the U.S. Geological Survey (USGS) is conducting bedrock geologic mapping, geoch

U-Pb SHRIMP and 40Ar/39Ar geochronologic data and backscatter electron (BSE) and panchromatic cathodoluminescent (CL) imagery of sample materials for study of dikes, country rock, and alteration systems, Butte, U.S.A.

These data are for a multidisciplinary study of dikes, country rock, and alteration systems, Butte, U.S.A. Results of the study are described and interpreted in Lund and others (2018). Data included are U-Pb SHRIMP geochronology for quartz porphyry dikes, 40Ar/39Ar thermochronologic data for biotite, hornblende, and K-feldspar from Butte granite country rock, and 40Ar/39Ar thermochronologic data f