U-Pb Isotopic Data and Ages of Zircon and Titanite from Rocks from the Western Alaska Range, Northern Aleutian Range, Taylor Mountains, and Tikchik Mountains Regions, Alaska

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: Jones III, J.V. (ORCID: 0000-0002-6602-5935)
Originator: Box, S.E. (ORCID: 0000-0002-5268-8375)
Originator: Todd, E. (ORCID: 0000-0002-4871-9730)
Originator: Bradley, D.C. (ORCID: 0000-0001-9116-5289)
Originator: Karl, S. (ORCID: 0000-0003-1559-7826)
Originator: Miller, M.L. (ORCID: 0000-0003-0285-4942)
Originator: O'Sullivan, P. (ORCID: 0000-0002-7247-5107)
Originator: Friedman, R.
Publication_Date: 20200721
Title:
U-Pb Isotopic Data and Ages of Zircon and Titanite from Rocks from the Western Alaska Range, Northern Aleutian Range, Taylor Mountains, and Tikchik Mountains Regions, Alaska
Geospatial_Data_Presentation_Form: tabular digital data
Publication_Information:
Publication_Place: Anchorage, Alaska
Publisher: U.S. Geological Survey, Alaska Science Center
Other_Citation_Details:
Suggested citation: Jones III, J.V., Box, S.E., Todd, E., Bradley, D.C., Karl, S., Miller, M.L., O'Sullivan, P., and Friedman, R., 2020, U-Pb isotopic data and ages of zircon, titanite, and detrital zircon from selected rocks from the western Alaska Range, northern Aleutian Range, Taylor Mountains, and Tikchik Mountains regions, Alaska: U.S. Geological Survey data release, https://doi.org/10.5066/P9K5NFKN.
Online_Linkage: https://doi.org/10.5066/P9K5NFKN
Description:
Abstract:
This data set contains U-Pb isotopic data and ages of zircon and titanite from igneous and metamorphic rocks collected from the western Alaska and northern Aleutian Range of south-central Alaska. The data sets also contain U-Pb isotopic data and ages of detrital zircon from sedimentary and metasedimentary rocks collected in the same region but also from the Taylor and Wood River Mountains of southwestern Alaska. The entire sample suite was collected as part of geological mapping and supporting geochemical and geochronological analysis conducted from 2004 to 2019 and funded by the Mineral Resources Program of the U.S. Geological Survey (USGS). Zircon and (or) titanite were obtained from igneous and metamorphic rocks to determine the crystallization age and (or) age of metamorphism for the bedrock samples. Bulk rock samples were processed into concentrated mineral separates in USGS laboratories in Denver, Colorado, or by Apatite to Zircon, Inc. (A2Z) and analyzed by USGS research scientists at the Stanford-USGS Sensitive High Resolution Ion Microprobe with Reverse-Geometry (SHRIMP-RG) at Stanford University. Detrital zircon grains were obtained from samples of sedimentary and metasedimentary rocks to determine depositional age and sediment sources. Detrital zircon grains were separated from bulk bedrock samples and analyzed at one of three different laboratories [University of British Columbia (UBC, 2004 to 2006), at A2Z (2006 to 2009), and GeoSep Services (GSS, 2015 to 2019)] using laser-ablation-inductively-coupled-plasma-mass spectrometry (LA-ICP-MS) techniques. The data tables accompanying this data release report the isotopic composition of uranium (U) and thorium (Th) measured in each grain, ratios of two isotopes of lead (207Pb and 206Pb) and two isotopes of uranium (235U and 238U), and the age of each grain. The SHRIMP-RG data table also reports concentrations of selected trace elements measured in each grain.
Purpose:
U-Pb zircon and titanite dates from igneous and metamorphic rocks aid in the interpretation of the age of original formation (e.g. crystallization age) and/or the timing of metamorphism of rocks with variety of compositions. U-Pb ages of detrital zircon grains aid in the interpretation of where the zircons in the rocks may have originated. The youngest detrital zircon date from any single sample also provides information about the maximum possible depositional age of the host sediment and, therefore, the geologic unit that contains it. Comparison of detrital zircon age populations from different samples test local to regional correlations of geologic units and aids in the reconstruction of geologic histories of large regions. In this study, detrital zircon U-Pb dates were used to understand the geologic history of large regions of southcentral and southwestern Alaska. These data will be used in support of multiple geological maps, reports, and papers that describe the geological framework and mineral resource potential of the region.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2020
Currentness_Reference: publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -159.2
East_Bounding_Coordinate: -150.7
North_Bounding_Coordinate: 62.6
South_Bounding_Coordinate: 59.6
Keywords:
Theme:
Theme_Keyword_Thesaurus: USGS Metadata Identifier
Theme_Keyword: USGS:ASC282
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: geoscientificInformation
Theme:
Theme_Keyword_Thesaurus: USGS Thesaurus
Theme_Keyword: geology
Theme_Keyword: geochronology
Theme_Keyword: uranium-lead analysis
Theme_Keyword: igneous rocks
Theme_Keyword: sedimentary rocks
Theme:
Theme_Keyword_Thesaurus: NASA GCMD Earth Science Keywords Thesaurus
Theme_Keyword: earth science
Theme:
Theme_Keyword_Thesaurus: GeoRef Thesaurus
Theme_Keyword: U/Pb
Theme_Keyword: SHRIMP data
Theme_Keyword: trace elements
Place:
Place_Keyword_Thesaurus: USGS Geographic Names Information System (GNIS)
Place_Keyword: Alaska
Place_Keyword: Alaska Range
Place_Keyword: Taylor Mountains
Place_Keyword: Wood River Mountains
Place_Keyword: Lake Clark National Preserve
Place_Keyword: Lake Clark National Park
Place_Keyword: Wood-Tikchik State Park
Place_Keyword: Nushagak Hills
Place_Keyword: Bonanza Hills
Place_Keyword: Chigmit Mountains
Place_Keyword: Jack Rabbit Hills
Access_Constraints: None
Use_Constraints:
None. Users are advised to read the metadata thoroughly to understand appropriate use and data limitations.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Alaska Science Center
Contact_Person: James V. Jones
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 4210 University Drive
City: Anchorage
State_or_Province: Alaska
Postal_Code: 99508-4626
Country: U.S.A.
Contact_Voice_Telephone: 907-786-7000
Contact_Electronic_Mail_Address: ascweb@usgs.gov
Cross_Reference:
Citation_Information:
Originator: Jones III, J.V. (ORCID: 0000-0002-6602-5935)
Publication_Date: 2009
Title: Western Alaska Range Metallogeny and Tectonics
Publication_Information:
Publication_Place: Anchorage, Alaska
Publisher: U.S. Geological Survey, Alaska Science Center
Online_Linkage: https://alaska.usgs.gov/portal/project.php?project_id=302
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Zircon crystals were run with zircon reference materials (R33, Temora2, MADDER), and the titanite samples were run with titanite reference materials (BLR1, MMS). The reference materials were analyzed until isotopic fractionation was stable and the variance in the measured 206Pb/238U and 207Pb/206Pb ratios was at or near 1 percent. Reference materials were subsequently analyzed together with unknowns at a regular interval to monitor fractionation throughout the analytical session. All measured isotopic ratios are reported with associated analytical uncertainty.
Logical_Consistency_Report:
No unexpected values are found in these data. Blank cells in the data tables indicate values were either not provided, not measured, or not calculated.
Completeness_Report: This data set is complete; no data were omitted.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Horizontal position was measured using hand-held GPS units with positional accuracy of 3 meters or less.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: Apatite to Zircon, Inc.
Publication_Date: 2018
Title: Detrital Zircon Analytical Methods
Publication_Information:
Publication_Place: Moscow, Idaho
Publisher: Apatite to Zircon, Inc. GeoSep Services
Other_Citation_Details:
This is a supplemental PDF document included in this data release. The file name is Supplemental_Info_Analytical_Methods_A2Z_GSS.pdf.
Type_of_Source_Media: pdf file
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2018
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: Supplemental Info Analytical Methods A2Z GSS
Source_Contribution:
Provides detailed description of laboratory methods and data modeling for U-Pb geochronology.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Stanford-USGS SHRIMP-RG Laboratory
Publication_Date: 2019
Title:
Titanite U-Pb geochronology and trace element analytical methods using Stanford-USGS SHRIMP-RG
Publication_Information:
Publication_Place: Palo Alto, California
Publisher: Stanford-USGS SHRIMP-RG laboratory
Other_Citation_Details:
This is a supplemental document included in this data release. The file name is Supplemental_Info_Analytical_Methods_StanfordUSGSSHRIMPRG.pdf.
Type_of_Source_Media: pdf file
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2019
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: SHRIMP-RG Methods
Source_Contribution:
Provides detailed descriptions of laboratory methods and data modeling for titanite U-Pb geochronology.
Process_Step:
Process_Description:
Detrital zircons were separated from bulk sample using lithium polytungstate and a centrifuge. Zircon grains were mounted in epoxy wafers and then ground down to expose the grain interior, and then polished. Isotopic analyses were performed with either a new Wave UP-213 or New Wave YAG 213 laser ablation system in line with Finnigan Element2 magnetic sector, inductively coupled plasma, mass spectrometer (ICP-MS) at Washington State University Geoanalytical Laboratory in Pullman, Washington. Detailed analytical procedures are described in the accompanying document, Supplemental_Info_Analytical_Methods_A2Z.pdf.
Process_Date: 2019
Process_Step:
Process_Description:
Titanite and zircon grains were separated from crushed and ground samples using standard magnetic and heavy liquid techniques, hand-picked under binocular microscope, and mounted in epoxy discs. The mounts were ground to expose the grain interior, further polished, and imaged using back-scattered electron (BSE) imaging on a JEOL 5600 SEM to identify internal grain zonation patterns and to identify any inclusions or other features such as cracks to be avoided during analysis. Titanite U-Pb ages were obtained with the Stanford-U.S. Geological (USGS) Sensitive High Resolution Ion Microprobe with Reverse-Geometry (SHRIMP-RG) at Stanford University. Detailed analytical procedures are described in the accompanying document, Supplemental_Info_Analytical_Methods_StanfordUSGSSHRIMPRG.pdf.
Process_Date: 2019
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Point
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution: 0.0001
Longitude_Resolution: 0.0001
Geographic_Coordinate_Units: Decimal degrees
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: GRS 1980
Semi-major_Axis: 6378137
Denominator_of_Flattening_Ratio: 298.257222101
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: geology_detritalZircon_westernAKRange_Jones.csv
Entity_Type_Definition:
Table of U-Pb detrital zircon laser-ablation-inductively-coupled-plasma-mass-spectrometry (LA-ICP-MS) data, reporting concentration and isotopic composition of uranium (U) and thorium (Th) measured in each grain, isotopic ratios of lead (Pb) and uranium (U), and the age of each grain calculated from isotope ratios. The table is presented in comma separated value (CSV) format and holds 8930 records.
Entity_Type_Definition_Source: Author defined
Attribute:
Attribute_Label: Sample
Attribute_Definition: Sample identifier as collected in the field.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Unique sample identifier; most labels consisting of the last two digits of the year collected, an abbreviation identifying the collector, and a number and possible suffix.
Attribute:
Attribute_Label: Analysis_Lab
Attribute_Definition:
Identifies the lab where analysis was done. Analyses were performed at University of British Columbia from 2004 to 2006, at Apatite to Zircon, Inc. from 2006 to 2009, and at GSS from 2015 to 2019.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: A2Z
Enumerated_Domain_Value_Definition: Apatite to Zircon, Inc., Moscow, Idaho
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: GSS
Enumerated_Domain_Value_Definition: GeoSep Services, Moscow, Idaho
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: UBC
Enumerated_Domain_Value_Definition: University of British Columbia, Vancouver, B.C. Canada
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Lab_Sample
Attribute_Definition:
Laboratory sample identifier assigned by A2Z or GSS. There is a one to one correspondence to the field sample identifier, Sample. Blanks cells indicate that the laboratory did not assign a different sample identifier.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Hyphenated numeric code assigned by the A2Z or GSS laboratory.
Attribute:
Attribute_Label: Mineral
Attribute_Definition: Material analyzed.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: DZ
Enumerated_Domain_Value_Definition: detrital zircon
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Analysis_Name
Attribute_Definition:
A unique identification assigned by the laboratory for an individual analysis.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
For samples run at UBC, the Analysis_Name is a numeric or alpha-numeric code, and often the concatenation of field Sample with a numeric suffix. For samples run at A2Z, the name is an alpha-numeric code including a variation of the Lab_Sample.
Attribute:
Attribute_Label: U_conc_ppm
Attribute_Definition:
Concentration of uranium (U) in parts per million (ppm). Value -9999 denotes value not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 4.0
Range_Domain_Maximum: 7930.9
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Th_conc_ppm
Attribute_Definition:
Concentration of thorium (Th) in parts per million (ppm). Value -9999 denotes value not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.1
Range_Domain_Maximum: 9620.8
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: U_Th_Ratio
Attribute_Definition:
The ratio of the concentration of uranium (U) to the concentration of thorium (Th). Value -9999 denotes ratio not calculated due to absence of reported U_conc_ppm and Th_conc_ppm.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.2
Range_Domain_Maximum: 488
Attribute_Units_of_Measure: unit-less value
Attribute:
Attribute_Label: 207Pb_235U_Ratio
Attribute_Definition: Total ratio of 207Pb to 235U.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.009
Range_Domain_Maximum: 120.333
Attribute_Units_of_Measure: unit-less value
Attribute:
Attribute_Label: 207Pb_235U_Ratio_Unc_1sig_abs
Attribute_Definition: Uncertainty (1-sigma) for the ratio of 207Pb to 235U.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00059
Range_Domain_Maximum: 28.52288
Attribute_Units_of_Measure: unit-less value
Attribute:
Attribute_Label: 206Pb_238U_Ratio
Attribute_Definition: Total ratio of 206Pb to 238U.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0007
Range_Domain_Maximum: 1.4709
Attribute_Units_of_Measure: unit-less value
Attribute:
Attribute_Label: 206Pb_238U_Ratio_Unc_1sig_abs
Attribute_Definition:
Uncertainty (1-sigma) for the ratio of 206Pb to 238U. Value -9999 denotes value not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00005
Range_Domain_Maximum: 0.27402
Attribute_Units_of_Measure: unit-less value
Attribute:
Attribute_Label: Error_Correlation
Attribute_Definition: Error correlation of the 207Pb/235U and 206Pb/238U ratios.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.01
Range_Domain_Maximum: 1.00
Attribute_Units_of_Measure: unit-less value
Attribute:
Attribute_Label: 207Pb_206Pb_Ratio
Attribute_Definition:
Total ratio of 207Pb to 206Pb. Value -9999 denotes value not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0059
Range_Domain_Maximum: 0.783
Attribute_Units_of_Measure: unit-less value
Attribute:
Attribute_Label: 207Pb_206Pb_Ratio_Unc_1sig_abs
Attribute_Definition:
Uncertainty (1-sigma) of the ratio of 207Pb to 206Pb. Value -9999 denotes value not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00030
Range_Domain_Maximum: 0.14192
Attribute_Units_of_Measure: unit-less value
Attribute:
Attribute_Label: 207Pb_235U_Age
Attribute_Definition:
Age in millions of years (Ma) calculated from the 207Pb/235U ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 9.1
Range_Domain_Maximum: 4872.3
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: 207Pb_235U_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years (Ma) for the age calculated from the 207Pb/235U ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.6
Range_Domain_Maximum: 1154.9
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: 206Pb_238U_Age
Attribute_Definition:
Age in millions of years (Ma) calculated from the 206Pb/238U ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 4.7
Range_Domain_Maximum: 5831.3
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: 206Pb_238U_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years (Ma) for the age calculated from the 206Pb/238U ratio.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.3
Range_Domain_Maximum: 1429.7
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: 207Pb_206Pb_Age
Attribute_Definition:
Age in millions of years (Ma) calculated from the 207Pb/206Pb ratio. Value -9999 denotes value not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.1
Range_Domain_Maximum: 4560
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: 207Pb_206Pb_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years (Ma) for the age calculated from the 207Pb/206Pb ratio. Value -9999 denotes value not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 1.1
Range_Domain_Maximum: 2298.9
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: Preferred_Age
Attribute_Definition:
Preferred age in millions of years (Ma) selected from one of the three following fields containing calculated ages for each grain: 207Pb_235U_Age or 206Pb_238U_Age or 207Pb_206Pb_Age. Zero values indicate an analysis that failed to yield an age. This may occur when the concentration of uranium (U) in a zircon or detrital zircon is zero parts per million (ppm). In such cases, U is not available to decay to lead (Pb).
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 4.7
Range_Domain_Maximum: 4558.0
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: Preferred_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years (Ma) for the preferred age. Zero values indicate an analysis that failed to yield an age.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.3
Range_Domain_Maximum: 1379.1
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: Preferred_Age_Type
Attribute_Definition:
Method used to calculate the value in Preferred_Age field for each individual analysis that yielded a valid result. Refer to the description of analytical methods, file Supplemental_Info_Analytical_Methods_A2Z.pdf, for more details.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The following values are used: 206Pb_238U_Age and 207Pb_206Pb_Age
Attribute:
Attribute_Label: Percent_Discordant
Attribute_Definition:
Discordance of 206Pb/238U age versus 207Pb/206Pb age, in percent. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -98.1
Range_Domain_Maximum: 99.7
Attribute_Units_of_Measure: percent
Detailed_Description:
Entity_Type:
Entity_Type_Label: geology_SHRIMPRGData_westernAKRange_Jones.csv
Entity_Type_Definition:
Table of U-Pb titanite and zircon SHRIMP-RG data, reporting the isotopic concentration of uranium (U) and thorium (Th) measured in individual grains, isotopic ratios of lead and uranium, and the age of each grain calculated from the isotope ratios. The table also reports concentrations of selected trace elements measured in the same grains. The table contains 1344 records and is presented in comma separated value (CSV) format.
Entity_Type_Definition_Source: Author defined
Attribute:
Attribute_Label: Sample
Attribute_Definition:
Sample number attributed when collected in the field. The value is unique for each sample but is repeated many times in this table because many individual grains from a single sample are analyzed. Descriptive and locational information about the sample is in table geology_sampleSummary_westernAKRange_Jones.csv, and may be linked through attribute Sample.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Unique sample identifier; most labels consisting of the last two digits of the year collected, an abbreviation identifying the collector, and a number and possible suffix.
Attribute:
Attribute_Label: Mineral
Attribute_Definition: Mineral analyzed
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The following values are used in this data set: titanite and zircon.
Attribute:
Attribute_Label: Mount
Attribute_Definition: Internal laboratory ID number for sample mount
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Alphanumeric code assigned by the laboratory
Attribute:
Attribute_Label: Standard
Attribute_Definition: Age reference material used on mount
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: BLR1
Enumerated_Domain_Value_Definition: Bear Lake diggings titanite standard
Enumerated_Domain_Value_Definition_Source:
Aleinikoff, J.A., Wintsch, R.P., Tollo, R.P., Unruh, D.M., Fanning, C.M., and Schmitz, M.D., 2007, Ages and origins of rocks of the Killingworth Dome, south-central Connecticut: Implications for the tectonic evolution of southern New England: American Journal of Science, v. 307, p. 63-118, https://doi.org/10.2475/01.2007.04. Mazdab, F.K., 2009, Characterization of flux-grown trace-element-doped titanite using the high-mass-resolution ion microprobe (SHRIMP-RG): The Canadian Mineralogist, v. 47, p. 813-831, https://doi.org/10.3749/canmin.47.4.813.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: MMS
Enumerated_Domain_Value_Definition: McClure Mountain syenite titanite standard
Enumerated_Domain_Value_Definition_Source:
Schoene, B., and Bowring, S.A., 2006, U-Pb systematics of the McClure Mountain syenite: thermochronological constraints on the age of the 40Ar/39Ar standard MMhb: Contributions to Mineralogy and Petrology, v. 151, p. 615-630, https://doi.org/10.1007/s00410-006-0077-4.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: R33
Enumerated_Domain_Value_Definition: Braintree Complex monzodiorite zircon standard
Enumerated_Domain_Value_Definition_Source:
Black, L.P., Kamo, S.L., Allen, C.M., Davis, D.W., Aleinikoff, J.N., Valley, J.W., Mundil, R., Campbell, I.H., Korsch, R.J., Williams, I.S., and Foudoulis, C. 2004, Improved 206Pb/238U microprobe geochronology by the monitoring of trace-element-related matrix effect; SHRIMP, ID-TIMS, ELA-ICP-MS and oxygen isotope documentation for a series of zircon standards. Chemical Geology, 205, p.115-140, https://doi.org/10.1016/j.chemgeo.2004.01.003.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: TEM2
Enumerated_Domain_Value_Definition: Middledale gabbroic diorite zircon standard
Enumerated_Domain_Value_Definition_Source:
Black, L.P., Kamo, S.L., Allen, C.M., Davis, D.W., Aleinikoff, J.N., Valley, J.W., Mundil, R., Campbell, I.H., Korsch, R.J., Williams, I.S., and Foudoulis, C. 2004, Improved 206Pb/238U microprobe geochronology by the monitoring of trace-element-related matrix effect; SHRIMP, ID-TIMS, ELA-ICP-MS and oxygen isotope documentation for a series of zircon standards: Chemical Geology, 205, p.115-140, https://doi.org/10.1016/j.chemgeo.2004.01.003.
Attribute:
Attribute_Label: Standard_Age
Attribute_Definition:
Assumed age of age reference material for data reduction, in millions of years before present (Ma, mega-annum).
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The assumed ages for the standards are: BLR1 (1047 Ma), MMS (524 Ma), R33 (419 Ma), and TEM2 (416.8 Ma).
Attribute:
Attribute_Label: Conc_Std
Attribute_Definition:
Concentration standard used to calibrate trace element concentrations in unknowns.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: BLR1
Enumerated_Domain_Value_Definition: Bear Lake diggings titanite standard
Enumerated_Domain_Value_Definition_Source:
Aleinikoff, J.A., Wintsch, R.P., Tollo, R.P., Unruh, D.M., Fanning, C.M., and Schmitz, M.D., 2007, Ages and origins of rocks of the Killingworth Dome, south-central Connecticut: Implications for the tectonic evolution of southern New England: American Journal of Science, v. 307, p. 63-118, https://doi.org/10.2475/01.2007.04. Mazdab, F.K., 2009, Characterization of flux-grown trace-element-doped titanite using the high-mass-resolution ion microprobe (SHRIMP-RG): The Canadian Mineralogist, v. 47, p. 813-831, https://doi.org/10.3749/canmin.47.4.813.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: MAD
Enumerated_Domain_Value_Definition: zircon reference material
Enumerated_Domain_Value_Definition_Source:
Barth, A.P., and Wooden, J.L., 2010, Coupled elemental and isotopic analyses of polygenetic zircons from granitic rocks by ion microprobe, with implications for melt evolution and the sources of granitic magmas: Chemical Geology, v. 277, p. 149-159, https://doi.org/10.1016/j.chemgeo.2010.07.017.
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: MAD559
Enumerated_Domain_Value_Definition: zircon reference material
Enumerated_Domain_Value_Definition_Source:
Coble, M.A., Vazquez, J.A., Barth, A.P., Wooden, J., Burns, D., Kylander-Clark, A., Jackson, S., and Vennari, C.E., 2018, Trace element characterization of MAD-559 zircon reference material of ion microprobe analysis: Geostandards and Geoanalytical Research, v. 42, p. 481-497, https://doi.org/10.1111/ggr.12238.
Attribute:
Attribute_Label: Analysis_Spot
Attribute_Definition: Internal ID number of individual analysis spot on this Mount.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Alphanumeric code assigned by the analyst. In general, the first number after the sample name indicates the unique grain from an individual sample. The second number indicates the unique spot for each individual grain.
Attribute:
Attribute_Label: AnalysisSpot_Mount
Attribute_Definition:
Concatenation of Analysis_Spot and Mount attributes. This is a unique identifier in this table.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Concatenation of Analysis_Spot and Mount attributes separated by and underscore (_).
Attribute:
Attribute_Label: Analysis_Date_Time
Attribute_Definition: The calendar date and time of the analysis.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Data formatted yyyy-mm-dd, hh:mm
Attribute:
Attribute_Label: U_conc_ppm
Attribute_Definition: Uranium concentration, in parts per million (ppm)
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.3
Range_Domain_Maximum: 18232.7
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Th_conc_ppm
Attribute_Definition: Thorium concentration, in parts per million (ppm)
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 8390.5
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: comm_206Pb
Attribute_Definition: 207Pb corrected common 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 475.78
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 238U_206Pb_Ratio
Attribute_Definition: Total ratio of 238U to 206Pb
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 2.2
Range_Domain_Maximum: 11225.4
Attribute:
Attribute_Label: 238U_206Pb_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on total ratio of 238U to 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.5
Range_Domain_Maximum: 73.6
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 207Pb_206Pb_Ratio
Attribute_Definition: Total ratio of 207Pb to 206Pb
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.025
Range_Domain_Maximum: 3.574
Attribute:
Attribute_Label: 207Pb_206Pb_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on total ratio of 207Pb to 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.1
Range_Domain_Maximum: 71.2
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 204Pbcorr_238U_206Pb_Ratio
Attribute_Definition: 204Pb-corrected ratio of 238U to 206Pb
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -157.8
Range_Domain_Maximum: 4638.8
Attribute:
Attribute_Label: 204Pbcorr_238U_206Pb_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected ratio of 238U to 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.6
Range_Domain_Maximum: 270.3
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 204Pbcorr_207Pb_206Pb_Ratio
Attribute_Definition: 204Pb-corrected ratio of 207Pb to 206Pb
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.000
Range_Domain_Maximum: 4.012
Attribute:
Attribute_Label: 204Pbcorr_207Pb_206Pb_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected ratio of 207Pb to 206Pb, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0
Range_Domain_Maximum: 18230.8
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 204Pbcorr_207Pb_235U_Ratio
Attribute_Definition: 204Pb-corrected ratio of 207Pb to 235U
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -4.884
Range_Domain_Maximum: 133.595
Attribute:
Attribute_Label: 204Pbcorr_207Pb_235U_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected ratio of 207Pb to 235U, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0
Range_Domain_Maximum: 18230.8
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: 204Pbcorr_206Pb_238U_Ratio
Attribute_Definition: 204Pb-corrected ratio of 206Pb to 238U
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -0.048
Range_Domain_Maximum: 133.655
Attribute:
Attribute_Label: 204Pbcorr_206Pb_238U_Ratio_Unc_1sig_perc
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected ratio of 206Pb/238U, in percent
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0
Range_Domain_Maximum: 270.3
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: Error_Correlation
Attribute_Definition: Error correlation of 207Pb/235U and 206Pb/238U ratios
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 4.01
Attribute:
Attribute_Label: 207Pbcorr_206Pb_238U_Age
Attribute_Definition:
207Pb-corrected 206Pb/238U age, in millions of years before present (mega-annum)
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -42.4
Range_Domain_Maximum: 2230.1
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: 207Pbcorr_206Pb_238U_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) on 207Pb-corrected 206Pb/238U age, in millions of years before present (mega-annum)
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0
Range_Domain_Maximum: 113.1
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: 204Pbcorr_207Pb_206Pb_Age
Attribute_Definition:
204Pb-corrected 207Pb/206Pb age, in millions of years before present (mega-annum). Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 12.9
Range_Domain_Maximum: 5977.3
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: 204Pbcorr_207Pb_206Pb_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) on 204Pb-corrected 207Pb/206Pb age, in millions of years before present (mega-annum). Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 11.0
Range_Domain_Maximum: 12605.3
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: Preferred_SHRIMP_Age
Attribute_Definition:
Preferred grain age for calculation of sample age (in millions of years, Ma) selected from one of the two following fields containing calculated ages: 207Pbcorr_206Pb_238U_Age or 204Pbcorr_207Pb_206Pb_Age.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -42.4
Range_Domain_Maximum: 2679.9
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: Preferred_SHRIMP_Age_Unc_1sig
Attribute_Definition:
Uncertainty (1-sigma) in millions of years (Ma) on preferred grain age
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0
Range_Domain_Maximum: 113.1
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: Preferred_SHRIMP_Age_Type
Attribute_Definition:
Method used to calculate the values in Preferred_SHRIMP_Age field for each individual analysis that yielded a valid result.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The only attributes in this data set are 204Pbcorr_207Pb_206Pb_Age and 207Pbcorr_206Pb_238U_Age.
Attribute:
Attribute_Label: Interpreted_Age_Included
Attribute_Definition:
Indication of whether or not analysis was used in the calculation of field UPb_Age_Ma in table geology_sampleSummary_westernAKRange_Jones.csv
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Y
Enumerated_Domain_Value_Definition: yes
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: N
Enumerated_Domain_Value_Definition: no
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Percent_Discordant
Attribute_Definition:
Discordance of 206Pb/238U age versus 207Pb/206Pb age, in percent. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -742.0
Range_Domain_Maximum: 104.0
Attribute_Units_of_Measure: percent
Attribute:
Attribute_Label: Y_ppm
Attribute_Definition:
Yttrium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 10419
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Nb_ppm
Attribute_Definition:
Niobium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 19.8
Range_Domain_Maximum: 2251.3
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: La_ppm
Attribute_Definition:
Lanthanum concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 3536.233
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Ce_ppm
Attribute_Definition:
Cerium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 11648.6
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Pr_ppm
Attribute_Definition:
Praseodymium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 1.09
Range_Domain_Maximum: 1458.71
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Nd_ppm
Attribute_Definition:
Neodymium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 7344.48
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Sm_ppm
Attribute_Definition:
Samarium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 2769.00
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Eu_ppm
Attribute_Definition:
Europium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.00
Range_Domain_Maximum: 2853.75
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Gd_ppm
Attribute_Definition:
Gadolinium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 20176.22
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Dy_ppm
Attribute_Definition: Dysprosium concentration in parts per million
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.09
Range_Domain_Maximum: 2386.69
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Er_ppm
Attribute_Definition:
Erbium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 1903.57
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Yb_ppm
Attribute_Definition:
Ytterbium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 3929.21
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Hf_ppm
Attribute_Definition:
Hafnium concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.09
Range_Domain_Maximum: 23601.22
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: 48Ti_ppm
Attribute_Definition:
Titanium (from mass 48) concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.03
Range_Domain_Maximum: 5300.15
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: 49Ti_ppm
Attribute_Definition:
Titanium (from mass 49) concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 18439.16
Attribute_Units_of_Measure: parts per million (ppm)
Attribute:
Attribute_Label: Fe_ppm
Attribute_Definition:
Iron concentration in parts per million. Value -9999 indicates not reported.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 10468.39
Attribute_Units_of_Measure: parts per million (ppm)
Detailed_Description:
Entity_Type:
Entity_Type_Label: geology_sampleSummary_westernAKRange_Jones.csv
Entity_Type_Definition:
Table with sample information, including location, rock description, and summary of geochronology analyses. This table contains 190 entries.
Entity_Type_Definition_Source: Author defined
Attribute:
Attribute_Label: Sample
Attribute_Definition:
Sample number assigned when sample was collected in the field. This attribute links to field Sample in tables geology_detritalZircon_westernAKRange_Jones.csv and geology_SHRIMPRGData_westernAKRange_Jones.csv.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Unique sample identifier; most labels consisting of the last two digits of the year collected, an abbreviation identifying the collector, and a number and possible suffix.
Attribute:
Attribute_Label: Lab_Sample
Attribute_Definition:
Laboratory sample identifier assigned by A2Z or GSS. Same as field Lab_Sample in table geology_detritalZircon_westernAKRange_Jones.csv.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Hyphenated numeric code assigned by the A2Z or GSS laboratory.
Attribute:
Attribute_Label: Latitude
Attribute_Definition: Latitude given in decimal degrees; datum NAD83
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 59.6773
Range_Domain_Maximum: 62.5143
Attribute_Units_of_Measure: decimal degree
Attribute:
Attribute_Label: Longitude
Attribute_Definition: Longitude given in decimal degrees; datum NAD83.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -159.1764
Range_Domain_Maximum: -150.7431
Attribute_Units_of_Measure: decimal degree
Attribute:
Attribute_Label: Rock_Class
Attribute_Definition: Basic rock classification of the sample
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Attributes in this dataset are igneous, metamorphic, and sedimentary.
Attribute:
Attribute_Label: Rock_Type
Attribute_Definition: Sample rock type
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: General rock description.
Attribute:
Attribute_Label: Rock_Comment
Attribute_Definition:
Additional sample description which may include more detailed rock description, location, geologic map unit. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Additional sample description which may include more detailed rock description, location, geologic map unit.
Attribute:
Attribute_Label: Analysis_Type
Attribute_Definition: Type of geochronologic analysis
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: U-Pb detrital zircon
Enumerated_Domain_Value_Definition: Uranium-lead analysis on detrital zircon
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: U-Pb titanite
Enumerated_Domain_Value_Definition: Uranium-lead analysis on titanite
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: U-Pb zircon
Enumerated_Domain_Value_Definition: Uranium-lead analysis on zircon
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Analysis_Lab
Attribute_Definition: Laboratory or contractor responsible for the analysis
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: A2Z
Enumerated_Domain_Value_Definition: Apatite to Zircon, Inc., Moscow, Idaho
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: GSS
Enumerated_Domain_Value_Definition: GeoSep Services, Moscow, Idaho
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Stanford-USGS SHRIMP-RG
Enumerated_Domain_Value_Definition:
Stanford-USGS Sensitive High Resolution Ion Microprobe with Reverse Geometry
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: UBC
Enumerated_Domain_Value_Definition: University of British Columbia, Vancouver, B.C., Canada
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: Analysis_Method
Attribute_Definition: Laboratory equipment and methodology used to collect data.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: LA-ICP-MS U-Pb
Enumerated_Domain_Value_Definition:
Laser ablation inductively coupled plasma mass spectrometry techniques for U-Pb
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: SHRIMP U-Pb
Enumerated_Domain_Value_Definition:
Sensitive high resolution ion microprobe with reverse geometry for U-Pb
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute:
Attribute_Label: UPb_Age_N_Grains_Total
Attribute_Definition: Total number of grains analyzed. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 3
Range_Domain_Maximum: 34
Attribute:
Attribute_Label: UPb_Age_Ma
Attribute_Definition:
Weighted average age calculated for sample in millions of years (Ma). Blanks cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 28.5
Range_Domain_Maximum: 585.9
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: UPb_Age_Unc_Ma
Attribute_Definition:
Uncertainty (2-sigma) of weighted average age calculated for sample, in millions of years (Ma). Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.3
Range_Domain_Maximum: 6.9
Attribute_Units_of_Measure: millions of years (Ma)
Attribute:
Attribute_Label: UPb_Age_Method
Attribute_Definition:
Method used to calculate the value in UPb_Age_Ma. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The only attribute in this data set is 'weighted average 206Pb/238U age'
Attribute:
Attribute_Label: UPb_Age_N_Grains
Attribute_Definition:
Number of analyses used to calculate the value in UPb_Age_Ma. Blanks cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 2
Range_Domain_Maximum: 32
Attribute:
Attribute_Label: UPb_Age_MSWD
Attribute_Definition:
Mean square of weighted deviates for calculated value in UPb_Age_Ma. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.22
Range_Domain_Maximum: 2.58
Attribute:
Attribute_Label: UPb_Age_Comment
Attribute_Definition:
Comments on the sample age or analytical observations. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Comments on the sample age or analytical observations.
Attribute:
Attribute_Label: UPb_Age_Interpretation
Attribute_Definition:
Geological significance of the interpreted age. Blank cells are present.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
Includes interpretations such as, cooling, crystallization, metamorphism, and detrital.
Detailed_Description:
Entity_Type:
Entity_Type_Label: geology_dataDictionary_westernAKRange_Jones.csv
Entity_Type_Definition:
Table listing the name of all fields in each table, with a brief description of the field and the data units, if applicable.
Entity_Type_Definition_Source: Author defined
Attribute:
Attribute_Label: Table
Attribute_Definition: Name of the data table the field is found in.
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The data tables in this data set include geology_detritalZircon_westernAKRange_Jones.csv, geology_SHRIMPData_westernAKRange_Jones.csv, and geology_sampleSummary_westernAKRange_Jones.csv.
Attribute:
Attribute_Label: Field
Attribute_Definition: Field name found in data table listed in field Table
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain:
The field names are single words or concatenated abbreviations that describe the contents of the field.
Attribute:
Attribute_Label: Description
Attribute_Definition: Brief description of the contents of the field
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Unrepresentable_Domain: Brief description of the contents of the field
Attribute:
Attribute_Label: Units
Attribute_Definition: The unit of measurement for applicable data fields
Attribute_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: %
Enumerated_Domain_Value_Definition: percent
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: degrees
Enumerated_Domain_Value_Definition: unit of angle measurement
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Ma
Enumerated_Domain_Value_Definition: mega-annum or million years
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: n/a
Enumerated_Domain_Value_Definition: not applicable
Enumerated_Domain_Value_Definition_Source: Author defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: ppm
Enumerated_Domain_Value_Definition: parts per million
Enumerated_Domain_Value_Definition_Source: Author defined
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Alaska Science Center
Contact_Address:
Address_Type: mailing and physical
Address: 4210 University Drive
City: Anchorage
State_or_Province: Alaska
Postal_Code: 99508-4626
Country: U.S.A.
Contact_Voice_Telephone: 907-786-7000
Contact_Electronic_Mail_Address: ascweb@usgs.gov
Resource_Description: Authoritative source for the data.
Distribution_Liability:
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: CSV
Format_Information_Content:
Data are distributed in a Zip package containing data in CSV format and FGDC metadata in XML and HTML formats. Supplementary information about laboratory methods are provided in PDF format.
File_Decompression_Technique:
Compression applied by the 7-Zip utility using default compression (5). The file can be decompressed and unpacked by open source or commercially available unzip tools.
Transfer_Size: 2.20
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: https://doi.org/10.5066/P9K5NFKN
Fees: None
Metadata_Reference_Information:
Metadata_Date: 20201125
Metadata_Review_Date: 20200707
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey, Alaska Science Center
Contact_Address:
Address_Type: mailing and physical address
Address: 4210 University Drive
City: Anchorage
State_or_Province: Alaska
Postal_Code: 99508-4626
Country: U.S.A.
Contact_Voice_Telephone: 907-786-7000
Contact_Electronic_Mail_Address: ascweb@usgs.gov
Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Generated by mp version 2.9.50 on Mon Jul 20 16:38:13 2020