Data

Ar/Ar data are for 12 samples that record the eruption age of tephra. The geochronology provides time constraints for the ages of tephra and interbedded sediments and fossils from Kenya and Ethiopia. Samples were collected by Erin Dimaggio (Pennsylvania State University), who brought them to the USGS Denver Argon Geochronology Laboratory for Ar/Ar analysis. Samples were analyzed in...

Gravity data were collected from 2022 through 2024 to provide more detailed data for geophysical profile modeling of the Midcontinent Rift System and associated structures. This data release provides the complete Bouguer anomaly gravity data for 256 new gravity stations to supplement existing data and replace erroneous existing data.

This dataset includes rock magnetic susceptibility and gamma ray spectrometer measurements from 243 outcrops in southwest Montana during 2023-2024. The measurements were collected to understand the causative sources of airborne magnetic and radiometric survey anomalies in the Idaho-Montana porphyry belt. Sixteen magnetic susceptibility measurements were collected at each analyzed site...

Porphyry copper deposits are the world's primary source of copper and can also host a variety of secondary commodities identified as critical by the U.S. Geological Survey (U.S. Geological Survey, 2022). These deposits occur primarily along convergent plate margins, and their metal association and geochemical characteristics are reflective of whether the deposit formed in continental...

Major, minor, and trace element data, as well as backscattered electron images, were collected for clinopyroxene crystals in alkaline silicate rocks (phonolite, tephriphonolite, latite, phonotephrite, and pyroxenite) of the Bear Lodge and Mineral Hill alkaline complexes, Wyoming. Samples of alkaline rocks thought to represent early and later stages of magmatism, based on observed...

This publication provides digital flight line data for a high-resolution magnetic and radiometric survey over part of central Arkansas and southern Missouri. The airborne geophysical survey was funded by the Earth Mapping Resources Initiative and was designed to meet the complimentary needs related to geologic mapping and mineral resource research. The survey covers an irregularly shaped...

There is a growing demand for commodities (elements, compounds, minerals) used in today's advanced technologies. Critical minerals are usually found in ore deposits that are deemed vital to economic and national security. National Geochemical Database on Ore Deposits: New data featuring fusion digestion (NGDOD) analytical methods contains chemistry and geologic information for 16,579 ore...

This data release provides digital flight-line and gridded data for a high-resolution airborne magnetic and radiometric survey over the central portion of the Colorado Mineral Belt, central Colorado. The Colorado Mineral Belt is a broad, northeast-southwest trending alignment of historic mining districts that have produced multiple types of commodities, including critical minerals that...

Geochemical, petrophysical, and depth to the Paleozoic-Precambrian basement interface from drill hole data for Mesoproterozoic igneous rocks and iron ore deposits of the St. Francois Mountains, southeast Missouri (MMDB) are provided in this data release. The samples were collected as part of various agency programs and projects from 1967 through 2019. Most samples were collected by...

Stable isotope analyses are reported (the ratios deuterium/hydrogen, carbon-13/carbon-12, oxygen-18/oxygen-16, and sulfur-34/sulfur-32) for ores and related rocks from the Pea Ridge, Lower Pilot Knob, Bourbon, Iron Mountain, and Kratz Spring iron oxide-apatite deposits in southeast Missouri; the Boss iron oxide-copper-gold deposit in southeast Missouri; the Gagaryah stratiform barite...

Surface electrical resistivity tomography (ERT) data were collected in September of 2018 near Ollalie North springs in the upper McKenzie River watershed of west-central Oregon. ERT data were acquired along a single transect on the north bank of Ollalie Creek using a combination of inverse Schlumberger, dipole-dipole, and Wenner arrays. These data were collected to contribute high...

Airborne electromagnetic (AEM) and magnetic survey data were collected during January and February 2023 over a distance of 3,799.3 line kilometers covering the Illinois River Basin and surrounding regions in Illinois and Indiana. Data were collected as part of the USGS Illinois River Basin Next Generation Water Observing Systems (NGWOS) project to improve understanding of depth to...