summary-data-locations: Identification numbers, coordinates, sample descriptions, and summary ages of each sample step-heating-data: Power output levels and resultant measurements from each sample run
Naibert, T.J., Benowitz, J.A., Wypych, Alicja, Sicard, K.R., and Twelker, Evan, 2018, 40Ar/39Ar data from the Tanacross D-1 and D-2, Big Delta B-4 and B-5, and Mount Hayes A-6 quadrangles, Alaska: Raw Data File RDF 2018-3, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
This is a point data set.
Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in decimal degrees.
The horizontal datum used is World Geodetic System of 1984.
The ellipsoid used is WGS 84.
The semi-major axis of the ellipsoid used is 6378137.
The flattening of the ellipsoid used is 1/298.257223563000025.
Generic example of a sample identifier: YYAAA9999X: YY=last two digits of the year the sample was collected, AAA=geologist's initials (one to three characters), 9999=unique station number, X= optional alpha character which indicates that multiple samples were collected at a given location or that multiple observations were recorded in the project database.
The lab sample number is typically identical to the field sample number. However, in some cases, the sample number provided by the lab does differ from the number assigned in the field. We provide both numbers to document instances in which the sample numbers in the lab files differ from the field sample number.
The samples presented in this report were collected by the authors or other DGGS staff.
The samples presented in this report were collected by the authors or other DGGS staff.
Range of values | |
---|---|
Minimum: | -146.927846 |
Maximum: | -141.279938 |
Units: | decimal degrees |
Range of values | |
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Minimum: | 63.196506 |
Maximum: | 64.465954 |
Units: | decimal degrees |
The type of material that was selected for dating varied according to mineral composition and grainsize of the submitted rock sample. This field specifies whether the age was derived from a mineral separate (generally 1 to 10 individual crystals dated together as a single run), a single crystal, or the whole rock.
The minerals selected for dating would typically be grains of biotite, hornblende, or muscovite.
A brief sample or station description.
The values are a concatenation of the integrated age determination and the calculated error associated with the integrated age determination
Value | Definition |
---|---|
NULL | A NULL or blank values indicates that the PLATEAU_AGE_MA value was not calculated by the lab |
The values are a concatenation of the plateau age determination and the calculated error associated with the plateau age determination
Range of values | |
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Minimum: | 38.4 |
Maximum: | 97.8 |
Units: | percent |
Value | Definition |
---|---|
NULL | A NULL or blank values indicates that the PLATEAU_AGE_MA value was not calculated by the lab |
Range of values | |
---|---|
Minimum: | 0.33 |
Maximum: | 2.39 |
Value | Definition |
---|---|
NULL | A NULL or blank values indicates that the PLATEAU_AGE_MA value was not calculated by the lab |
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Value | Definition |
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NULL | A NULL or blank values indicates that the W_M_AGE_MA value was not calculated by the lab |
The values are a concatenation of the weighted average age determination and the calculated error associated with the weighted mean average age determination
Value | Definition |
---|---|
NULL | A NULL or blank values indicates that the ISOCHRON_AGE value was not provided by the lab |
The values are a concatenation of the isochron age determination and the calculated error associated with the isochron age determination
Value | Definition |
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NULL | A NULL or blank values indicates that the value was not calculated by the lab |
Value | Definition |
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NULL | A NULL or blank values indicates that the value was not calculated by the lab |
Free text
A discussion of the preferred age for each analysis is provided in the accompanying lab report. The possible values are: plateau, isochron, weighted average, or integrated.
The preferred age for each analysis is discussed in detail in the accompanying lab report.
Generic example of a sample identifier: YYAAA9999X: YY=last two digits of year, AAA=geologist's initials (one to three characters), 9999=unique station number, X= optional alpha character which indicates that multiple samples were collected at a given location or that multiple observations were recorded in the project database.
The lab sample number is typically identical to the field sample number. However, in some cases, the sample number provided by the lab does differ from the number assigned in the field. We provide both numbers to document instances in which the sample numbers in the lab files differ from the field sample number.
Value | Definition |
---|---|
NULL | A NULL or blank values indicates that the values in the row were calculated by weighting the individual heating steps by the fraction of 39Ar released. |
Range of values | |
---|---|
Minimum: | 500 |
Maximum: | 9000 |
Units: | megawatts |
Value | Definition |
---|---|
NULL | The values in the row were derived from a heating step |
Integrated | the values in this row were calculated by weighting the individual heating steps by the fraction of 39Ar released |
Value | Definition |
---|---|
NULL | A NULL or blank values indicates that the value was not applicable or not calculated by the lab |
Range of values | |
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Minimum: | 0.0017 |
Maximum: | 1 |
Range of values | |
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Minimum: | 0.2319 |
Maximum: | 41.46334 |
Range of values | |
---|---|
Minimum: | 0.01037 |
Maximum: | 9.54597 |
Range of values | |
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Minimum: | -0.08208 |
Maximum: | 1.16705 |
Range of values | |
---|---|
Minimum: | 0.00038 |
Maximum: | 0.73712 |
Range of values | |
---|---|
Minimum: | -0.05612 |
Maximum: | 0.13677 |
Range of values | |
---|---|
Minimum: | 0.00007 |
Maximum: | 0.03167 |
Range of values | |
---|---|
Minimum: | -8205.58955 |
Maximum: | 97.42027 |
Range of values | |
---|---|
Minimum: | 0.25173 |
Maximum: | 387396.3875 |
Range of values | |
---|---|
Minimum: | -0.15059 |
Maximum: | 2.14315 |
Range of values | |
---|---|
Minimum: | 0.0007 |
Maximum: | 1.35268 |
Range of values | |
---|---|
Minimum: | -0.02209 |
Maximum: | 0.12175 |
Range of values | |
---|---|
Minimum: | 0.00004 |
Maximum: | 0.01331 |
Range of values | |
---|---|
Minimum: | 1.06933 |
Maximum: | 24.71558 |
Range of values | |
---|---|
Minimum: | 0.02407 |
Maximum: | 13.21114 |
Range of values | |
---|---|
Minimum: | 9.75 |
Maximum: | 212.88 |
Units: | MA |
Range of values | |
---|---|
Minimum: | 0.34 |
Maximum: | 111.3 |
Units: | MA |
WeightedAverageOfJFromStandards value and error
The DGGS 2017 Northeastern Tanacross and Richardson projects were funded through State of Alaska general funds. The Wrangellia project was funded by Capital Improvement Project funds through the State's Strategic and Critical Minerals Assessment project. The authors acknowledge the contributions of the 2017 Richardson and Northeastern Tanacross project field crew: Melanie B. Werdon, Jen E. Athey, Amanda L. Willingham, Alec C. Lockett, and the 2013 Wrangellia field crew: Larry K. Freeman, Rainer J. Newberry, Erik N. Bachmann, David A. Reioux, Amy L. Tuzzolino, and T. Colby Wright.
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The Northeastern Tanacross map area lies within the Yukon-Tanana terrane on the boundary between the Fortymile and Lake George Assemblages. The map area encompasses documented porphyry Cu-Mo-Au deposits including Taurus, Fishhook (also known as SW Pika), and Pika Canyon, and is adjacent to the Fortymile Mining District. Previously published geologic mapping includes a reconnaissance 1:250,000-scale map and a slightly modified map published by the USGS. New DGGS mapping will provide detailed geologic context for the known porphyry systems in the map area and links to mineral occurrences elsewhere in the region, including across the border in Yukon, Canada. The Richardson project area in Interior Alaska is approximately 30-50 miles west of the active Pogo gold mine and includes several active intrusion-related gold exploration properties, including Naosi, Uncle Sam, and Democrat Lode. Recent DGGS geologic mapping will improve the understanding of the area's geology and controls on gold mineralization to facilitate industry exploration targeting. The Wrangellia project area lies along the Denali Highway in the eastern Wrangellia Terrane, which includes magmatic sulfide nickel-copper-cobalt and platinum-group element mineralization hosted in mafic-ultramafic rocks in a structurally complex geologic setting. The sample presented in this report comes from the Clearwater Terrane, an isolated region of metamorphic rock with Permian protoliths caught up in the regional Talkeetna Shear Zone.
Benowitz, J.A., Layer, P.W., and Twelker, Evan, 2014, 40Ar/39Ar data from rocks collected in 2013 in the Wrangellia mineral assessment area, Gulkana, Healy, Mount Hayes, and Talkeetna Mountains quadrangles, Alaska: Raw Data File RDF 2014-18, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, Newberry, R.J., Freeman, L.K., Sicard, K.R., Reioux, D.A., and Bachmann, E.N., 2013, DGGS geologic and mineral-resource assessment of the western Wrangellia terrane, central Alaska: Initial progress report (presentation): Alaska Miners Association Annual Convention, Anchorage, Alaska, November 4-10, 2013: Poster and Presentation Twelker, Evan and others, 2013, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, Wypych, Alicja, and Newberry, R.J., 2014, New data and insight on the Late Triassic Wrangellia magmatic Ni-Cu-Co-PGE system in the Talkeetna Mountains, central Alaska (poster): Society of Economic Geologists 2014 Conference, September 27-30, 2014: Poster and Presentation Twelker, Evan and others, 2014, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Wypych, Alicja, Twelker, Evan, Freeman, L.K., Lande, Lauren, Newberry, R.J., Reioux, D.A., and Sicard, K.R., 2015, Major-oxide and trace-element geochemical data from rocks collected in 2015 in the Wrangellia mineral assessment area, Alaska: Raw Data File RDF 2015-16, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, and Burns, L.E., 2014, New geochemical and geophysical data from the western Wrangellia minerals assessment area (presentation): Alaska Miners Association 24th Biennial Mining Conference, Fairbanks, Alaska April 7-13, 2014: Poster and Presentation Twelker, Evan and Burns, L.E., 2014, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Wypych, Alicja, Twelker, Evan, Lande, L.L., and Newberry, R.J., 2015, Along-strike geochemical variations in the Late Triassic Nikolai magmatic system, Wrangellia, central Alaska (poster number V31D-3059): American Geophysical Union 2015 Fall Meeting, December 14-18, 2015: Poster and Presentation Wypych, Alicja and others, 2015, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Benowitz, J.A., Layer, P.W., Wypych, Alicja, and Twelker, Evan, 2017, 40Ar/39Ar data from rocks collected in the 2015 Wrangellia mineral assessment project area, Mount Hayes A-5, Mount Hayes B-6, and Talkeetna Mountains D-2 quadrangles, Alaska: Raw Data File RDF 2017-1, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, and Lande, Lauren, 2015, DGGS geological investigations in western Wrangellia (presentation): Alaska Miners Association Annual Convention, Anchorage, Alaska, November 1-5, 2015: Poster and Presentation Twelker, Evan and Lande, Lauren, 2015, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Benowitz, J.A., Layer, P.W., Wypych, Alicja, and Twelker, Evan, 2015, 40Ar/39Ar data from the Talkeetna Mountains C-4 Quadrangle and adjoining areas, central Alaska: Raw Data File RDF 2015-10, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, Hubbard, T.D., Wypych, Alicja, Sicard, K.R., Newberry, R.J., Reioux, D.A., Freeman, L.K., and Lande, L.L., 2015, Geologic map of the Talkeetna Mountains C-4 Quadrangle and adjoining areas, central Alaska: Preliminary Interpretive Report PIR 2015-6, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Wypych, Alicja, Twelker, Evan, Freeman, L.K., Lande, Lauren, Newberry, R.J., Reioux, D.A., and Sicard, K.R., 2014, Major-oxide and trace-element geochemical data from rocks collected in 2014 in the Wrangellia mineral assessment area, Talkeetna Mountains C-4, C-3, and B-4 quadrangles, Alaska: Raw Data File RDF 2014-22, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Lande, Lauren, Newberry, R.J., and Twelker, Evan, 2015, A petrological model for emplacement of the ultramafic Ni-Cu-PGE Alpha complex, eastern interior Alaska (poster): Geological Society of America Cordilleran Section - 111th Annual Meeting, Anchorage, Alaska, May 11-13, 2015: Poster and Presentation Lande, Lauren and others, 2015, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, Wypych, Alicja, Sicard, K.R., Newberry, R.J., Freeman, L.K., Reioux, D.A., and Lande, Lauren, 2014, Preliminary results from 2014 geologic mapping in the Talkeetna Mountains, Alaska (presentation): Alaska Miners Association Annual Convention, Anchorage, Alaska, November 3-9, 2014: Poster and Presentation Twelker, Evan and others, 2014, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, Bachmann, E.N., Freeman, L.K., Newberry, R.J., Reioux, D.A., Sicard, K.R., Tuzzolino, A.L., Wright, T.C., and Wypych, Alicja, 2014, Major-oxide, minor-oxide, and trace-element geochemical data from rocks and stream sediments in the Wrangellia mineral assessment area, Gulkana, Healy, Mount Hayes, and Talkeetna Mountains quadrangles, Alaska: Raw Data File RDF 2014-3, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, and O'Sullivan, P.B., 2016, U-Pb zircon age data from meta-igneous rocks in the Clearwater Mountains, Mount Hayes A-6 Quadrangle, Alaska: Raw Data File RDF 2016-8, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Todd, Erin, Kylander-Clark, Andrew, Wypych, Alicja, Twelker, Evan, and Sicard, K.R., 2017, 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: Raw Data File RDF 2017-2, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Wypych, Alicja, Twelker, Evan, Athey, J.E., Lockett, A.C., Naibert, T.J., Sicard, K.R., Werdon, M.B., and Willingham, A.L., 2017, Major-oxide and trace-element geochemical data from rocks collected in the Tanacross C-1, D-1, and D-2 quadrangles, Alaska in 2017: Raw Data File RDF 2017-10, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
Twelker, Evan, Wypych, Alicja, Sicard, K.R., Naibert, T.J., Werdon, M.B., Athey, J.E., Willingham, A.L., and Lockett, A.C., 2017, Major-oxide and trace-element geochemical data from rocks collected in the Richardson mining district, Big Delta Quadrangle, Alaska: Raw Data File RDF 2017-11, Alaska Division of Geological & Geophysical Surveys, Fairbanks, Alaska, United States.Online Links:
This data set is being released into the DGGS Raw Data File series. The information has been examined by several geologists familiar with the study area, but the data and accompanying report have not been formally reviewed for technical content or for conformity to the editorial standards of DGGS. Questions regarding the accuracy of the analytical values can be best answered by the originating lab.
Sample location coordinates (in WGS84 datum) were obtained using GPS-enabled field tablets, with a typical reported accuracy of about 10 meters.
This data release is complete.
not applicable
Are there legal restrictions on access or use of the data?
- Access_Constraints:
- This report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below).
- Use_Constraints:
- Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product.
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RDF 2018-3
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Data format: | ASCII tabular files |
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Network links: |
<http://doi.org/10.14509/30112> |
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