Zircon U-Pb age data, Alaska Highway Corridor, Tanacross and Nabesna quadrangles, Alaska
Dates
Publication Date
2014
Start Date
2009
End Date
2014
File Modification Date
2014-07-21 12:16:00
Citation
Solie, D.N., O'Sullivan, P.B., Werdon, M.B., Freeman, L.K., Newberry, R.J., Szumigala, D.J., and Hubbard, T.D., 2014, Zircon U-Pb age data, Alaska Highway Corridor, Tanacross and Nabesna quadrangles, Alaska: Alaska Division of Geological & Geophysical Surveys, http://dx.doi.org/10.14509/27322.
Summary
Twenty-two igneous and metamorphic rock samples were collected in a 20-km-long swath centered on the Alaska Highway between Tetlin Junction, Alaska, and the Canada border. Igneous and metamorphic rock samples were submitted to the Apatite to Zircon, Inc. laboratory (A2Z), where zircon U-Pb age analysis, using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), was performed by Paul O'Sullivan. The 15 felsic plutonic rock samples and one gabbro sample yield Cretaceous zircon U-Pb weighted-mean ages ranging from 95.7 Ma to 106.2 Ma. Zircons from a metadiorite yield a Triassic weighted-mean age of about 241.9 Ma. Metamorphic zircons from two samples with felsic igneous protoliths yield Mississippian weighted-mean [...]
Summary
Twenty-two igneous and metamorphic rock samples were collected in a 20-km-long swath centered on the Alaska Highway between Tetlin Junction, Alaska, and the Canada border. Igneous and metamorphic rock samples were submitted to the Apatite to Zircon, Inc. laboratory (A2Z), where zircon U-Pb age analysis, using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), was performed by Paul O'Sullivan. The 15 felsic plutonic rock samples and one gabbro sample yield Cretaceous zircon U-Pb weighted-mean ages ranging from 95.7 Ma to 106.2 Ma. Zircons from a metadiorite yield a Triassic weighted-mean age of about 241.9 Ma. Metamorphic zircons from two samples with felsic igneous protoliths yield Mississippian weighted-mean ages of 351.7 Ma and 354.6 Ma. Detrital zircons from two metaconglomerates yield individual grain ages from 100 Ma to 1,811 Ma, but are predominantly between 300 Ma and 345 Ma. Detrital zircons from a quartzite yield peaks at about 2,648 Ma, 1,946 Ma, and 1,807 Ma. Samples were analyzed for a variety of suites of major and trace elements depending on the sample type. The analytical data tables associated with this report are being released in digital format.
The Alaska Division of Geological & Geophysical Surveys (DGGS) conducted a multi-year project (from 2006 through 2010) studying the geology and geologic hazards along the Alaska Highway corridor. As part of the bedrock geologic mapping, samples were collected for geochronologic analyses using 40Ar/39Ar, fission-track, and U-Pb dating techniques. Summaries of analytical results appear on bedrock-geologic maps that are being published in three segments. This report supplies the supporting data for the zircon U-Pb age results from the easternmost segment of the project, in the Tanacross and Nabesna quadrangles.
