Filters: Tags: zircon (X)18 results (132ms)
This map layer includes refractory, abrasive, and other industrial minerals operations in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the U.S. Geological Survey, and the operations are those considered active in 2003 and surveyed by the MIT. This is a revised version of the June 2004 map layer.
Apatite and zircon U/Pb and fission track geochronologic and thermochronologic data along the Fall Line of the southeastern United States
This data release contains apatite and zircon U/Pb and fission track data for six samples collected along the Fall Line of the southeastern United States, from Virginia to the Georgia-South Carolina border. The data resolve phases of rapid exhumational cooling in the Permo-Triassic, additional cooling in the Jurassic-Early Cretaceous and slower cooling since the middle of the Cretaceous. The data are also compatible with an episode of burial/magmatic heating in the Triassic-Jurassic. Overall, these data may explain the lack of preserved Upper Jurassic-earliest Cretaceous strata beneath onshore areas of the southeastern United States.
Tabular geochronologic and geochemical data from metasedimentary and associated rocks in the Lane Mountain area, San Bernardino County, California
This dataset provides geochronologic and geochemical data for selected metasedimentary and associated rock samples collected in the Lane Mountain area about 20 kilometers northeast of Barstow, California. Geochronologic data were obtained for 24 samples, and geochemical data were obtained for 5 of these. The dataset consists of four tables in csv (comma separated values) format: (1) sample localities and lithology; (2) LA-SF-ICPMS (Laser Ablation Sector Field Inductively Coupled Plasma Mass Spectrometry) U-Pb (uranium-lead) zircon geochronologic data; (3) SHRIMP-RG (Sensitive High-Resolution Ion Microprobe-Reverse Geometry) U-Pb zircon geochronologic data; and (4) whole-rock geochemical data determined by ICP-AES-MS...
U-Pb zircon age data from meta-igneous rocks in the Clearwater Mountains, Mount Hayes A-6 Quadrangle, Alaska
We report U-Pb zircon geochronology results for one metavolcanic and one metaplutonic rock sample from the Mount Hayes A-6 Quadrangle of central Alaska. These samples are representative of rock units assigned to the Clearwater terrane of Jones and others (1987), a sequence of greenschist-grade metavolcanic and metasedimentary rocks of poorly constrained age and tectonic origin. Our results indicate a crystallization age of 277.33 +/- 11.84 Ma for a felsic metavolcanic rock, and a 268.05 +/- 11.64 Ma crystallization age for a granitic metaplutonic unit intruding the former.
Zircon U-Pb and 40Ar/39Ar results from dikes collected within the Bruin Bay fault zone, lower Cook Inlet
This data release presents zircon U-Pb LA-ICP-MS geochronology from igneous rocks exposed in a coastal exposure at Ursus Head, Iliamna C-2 Quadrangle. Sills and dikes exposed in a coastal exposure at Ursus Head are deformed within the Bruin Bay fault zone. Common dikes intruding late Triassic Kamishak Formation strata composing the hanging-wall of the Bruin Bay fault are cut by numerous small-scale, low-angle, bedding-parallel, and high angle contractional faults. Sample 09MAW006A collected from one of many dikes deformed in the fault zone produced a uni-modal distribution of zircon ages of with a weighted mean of 206.92 +/-0.96 (2 sigma, n=47) and an MSWD of 1.1. Sample 09BG020C collected from a sill of more mafic...
The Geochronology Repository is an active collection of radiometric ages generated by the Montana Bureau of Mines and Geology (MBMG). The geochronology data are organized in a public facing database with attributes describing field location, geologic context, geochronology method, and laboratory of analysis. Hand samples, thin sections, heavy mineral separates, and grain mounts of processed samples are stored in the MBMG Geologic Materials Repository. The collection is available to the public.
This data release contains the U.S. salient statistics and world production data extracted from the ZIRCONIUM AND HAFNIUM data sheet of the USGS Mineral Commodity Summaries 2023.
U-Pb analyses were performed on igneous rocks from the Ray Mountains area of west-central Alaska. These new age analyses will allow us to better evaluate the geochronology of the granitic rocks that are the apparent source of the alluvial REE and tin resources. The plutonic samples have ages ranging from 98.0 +/- 0.9 Ma to 111.6 +/- 1.0 Ma. The sample location coordinates and analytical data tables associated with this report are available in digital format as comma-separated value (CSV) files.
This data set includes mineral and metal operations in the United States. The data represent commodities monitored by the National Minerals Information Center of the USGS, and the operations included are those considered active in 2003 and surveyed by the MIT. Additional mineral and metal operations information can be obtained from the U.S. Geological Survey National Minerals Information Center web page at: <http://minerals.usgs.gov/minerals/>
Zircon U-Pb data for ash-fall tuffs and sandstones of the Cenozoic Amargosa Valley and Bat Mountain Formations exposed on Bat Mountain, southern Funeral Mountains, California, USA
This document includes two suites of zircon U-Pb data that establish a detailed chronostratigraphy for Cenozoic strata exposed on Bat Mountain of the southern Funeral Mountains, California, USA. The first suite of data includes detrital zircon U-Pb age distributions that characterize the maximum depositional age and provenance of five sandstone samples from the Oligocene-Miocene Amargosa Valley Formation (N=4) and the Miocene Bat Mountain Formation (N=1). The second suite of data includes zircon U-Pb data for five ash-fall tuffs that are interbedded with strata of the Amargosa Valley and Bat Mountain Formations. Together, interpreted eruption ages of tuffs and maximum depositional ages of sandstones constrain deposition...
U-Pb and Lu-Hf isotope, age, and trace-element data from zircons at four sites in the western Alaska Range and Talkeetna Mountains, Alaska
This Division of Geological & Geophysical Surveys (DGGS) Raw Data File presents U-Pb geochronology and Lu-Hf isotopic compositions, age-dating results, and additional trace-elemental composition of zircons from four granitoids sampled during investigations by DGGS geologists in the western Alaska Range and the Talkeetna Mountains. The purpose of the Lu-Hf and U-Pb isotopic study was to better understand the Jurassic through early Tertiary magmatic and tectonic evolution of the Alaska Range and the significance of that magmatism for the formation of metallic mineral deposits. The U-Pb isotopic data also serve to further refine the crystallization age of plutons, which were previously ambiguous in 40Ar/39Ar geochronology...
U-Pb data for inherited cassiterite in "Tin Granites", an example from the Yazov Granite, Eastern Siberia
Zircon (ZrSiO4) and cassiterite (SnO2) samples were collected by the U.S. Geological Survey (USGS) from the Yazov Granite, Transbaikalia region, Eastern Siberia, Russia. Samples (in the form of mounted loose grains) were prepared and analyzed for direct age dating on a laser ablation inductively coupled plasma mass spectrometer (LA–ICPMS) system at the USGS in Denver, Colorado from February 2017 to June 2019. The data indicate that high tin concentrations in the Yazov Granite are caused by inheritance of older cassiterite crystals and may imply that these granites cannot be genetically related to primary tin ore deposits of the region. These results have broad implications in understanding how critical elements,...
Zircon U-Pb and 40Ar/39Ar results from dikes collected within the Bruin Bay fault zone, lower Cook Inlet
This data release presents 40Ar/39Ar step-heating geochronology results from rocks collected roughly 7 km southwest of Contact Point, Iliamna B-3 Quadrangle. Samples obtained from a felsic dike intruding the principal Bruin Bay fault plane near Contact Point produced biotite and plagioclase 40Ar/39Ar ages of 36.5 +/- 0.8 Ma and 31.5+/-0.7 Ma, respectively. The age dates inform stratigraphic, structural, and geochronologic studies along the western margin of lower Cook Inlet basin. The accompanying report also presents zircon U-Pb LA-ICP-MS geochronology results for dikes near Ursus Head.
This data release contains the U.S. salient statistics and world production data extracted from the ZIRCONIUM AND HAFNIUM data sheet of the USGS Mineral Commodity Summaries 2022.
The Geologic Materials Repository is an active collection of research specimens gathered by the Montana Bureau of Mines and Geology (MBMG). Curated specimens include hand samples, thin sections, powder residues, or heavy mineral separates. The geologic materials are organized in containers and stored on shelves in a designated building located on the Montana Technological University campus. MBMG maintains a public facing database of the collection?s inventory that includes attributes describing the field location, geologic context, materials curated, storage information, and record of analytical work. The collection is available to the public.
Crustal evolution of southern Laurentia during the Paleoproterozoic: Insights from zircon Hf isotopic studies of ca. 1.75 Ga rocks in central Colorado
Lu-Hf depleted mantle model (TDM) ages, obtained by analysis of zircons previously dated by U-Pb methods, demonstrate that ca. 1.75 Ga bimodal Paleoproterozoic rocks in the Gunnison-Salida region of central Colorado, and by extension in much of the southwestern U.S., were formed by partial melting of preexisting crustal rocks, the ages of which mostly ages greater than 2.0 Ga indicate that range from 1.83 to 1.87 Ga. Some calculated Lu-Hf TDM even older crust was probably involved, consistent with the limited presence of ca. 2.5 Ga xenocrystic zircons in some rocks. These results suggest that rocks related to the Trans-Hudson and Penokean orogens are cryptically present much farther to the south than previously...
Tabular geochronologic, geochemical, and isotopic data from igneous rocks in the Lane Mountain area, San Bernardino County, California
This dataset provides geochronologic, geochemical, and isotopic data for selected igneous rock samples collected in the Lane Mountain area about 20 kilometers northeast of Barstow, California. Uranium-lead (U-Pb) zircon geochronologic and whole-rock geochemical data were obtained for 62 samples of which 28 are from Permian to Triassic plutonic rocks and dikes, 24 are from Late Jurassic plutonic rocks, 6 are from Late Cretaceous plutonic rocks and dikes, and 4 are from Miocene volcanic rocks, Rubidium-strontium (Rb-Sr) isotopic data were obtained for 8 of the Permian to Triassic samples, 9 of the Late Jurassic samples, and 4 of the Late Cretaceous samples. Oxygen isotope data were obtained for 2 Permian to Triassic...