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Comparison of Conventional K–Ar and 40Ar/39Ar Dating of Young Mafic Volcanic Rocks

Published online by Cambridge University Press:  20 January 2017

Marvin A. Lanphere
Marvin A. Lanphere*
Affiliation:
U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025
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Abstract

K–Ar and 40Ar/39Ar ages have been measured on nine mafic volcanic rocks younger than 1 myr from the Snake River Plain (Idaho), Mount Adams (Washington), and Crater Lake (Oregon). The K–Ar ages were calculated from Ar measurements made by isotope dilution and K2O measurements by flame photometry. The 40Ar/39Ar ages are incremental-heating experiments using a low-blank resistance-heated furnace. The results indicate that high-quality ages can be measured on young, mafic volcanic rocks using either the K–Ar or the 40Ar/39Ar technique. The precision of an 40Ar/39Ar plateau age generally is better than the precision of a K–Ar age because the plateau age is calculated by pooling the ages of several gas increments. The precision of a plateau age generally is better than the precision of an isotope correlation (isochron) age for the same sample. For one sample the intercept of the isochron yielded an 40Ar/36Ar value significantly different from the atmospheric value of 295.5. Recalculation of increment ages using the isochron intercept for the composition of nonradiogenic Ar in the sample resulted in much better agreement of ages for this sample. The results of this study also indicate that, given suitable material and modern equipment, precise K–Ar and 40Ar/39Ar ages can be measured on volcanic rocks as young as the latest Pleistocene, and perhaps even the Holocene.

Keywords

volcanic rocksgeochronologyK–Ar datingAr/Ar datingwestern United States
Type
Research Article
Information
Quaternary Research , Volume 53 , Issue 3 , May 2000 , pp. 294 - 301
Copyright
University of Washington

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References

Baksi, A.K., Hsu, V., McWilliams, M.O., Farrar, E., (1992). 40Ar/39Ar dating of the Brunhes–Matuyama geomagnetic field reversal. Science 256, 356–357.CrossRefGoogle Scholar
Bacon, C.R., Lanphere, M.A., (1990). The geologic setting of Crater Lake, Oregon. Drake, E.T., Larson, G.L., Dymond, J., Collier, R., Crater Lake an Ecosystem Study Pacific Division/American Association for the Advancement of Science, San Francisco.19–27.Google Scholar
Champion, D.E., Lanphere, M.A., Kuntz, M.A., (1988). Evidence for a new geomagnetic reversal from lava flows in Idaho. Journal of Geophysical Research 93, .Google Scholar
Champion, D.E., Lanphere, M.A., Anderson, S.R., (1996). Further verification and 40Ar/39Ar dating of the Big Lost Reversed Polarity Subchron from drill core subsurface samples of the Idaho National Engineering Laboratory, Idaho. EOS 77, F165.Google Scholar
Dalrymple, G.B., (1989). The GLM continuous laser system for 40Ar/39Ar dating: Description and performance characteristics. U.S. Geological Survey Bulletin 1890, 89–96.Google Scholar
Dalrymple, G.B., Lanphere, M.A., (1969). Potassium–Argon Dating. Freeman, San Francisco.Google Scholar
Dalrymple, G.B., Lanphere, M.A., (1971). 40Ar/39Ar technique of K–Ar dating: A comparison with the conventional technique. Geochimica et Cosmochimica Acta 12, 300–308.Google Scholar
Dalrymple, G. B, Alexander, E. C. Jr, Lanphere, M. A., Kraker, G. P., (1981). Irradiation of Samples for 40Ar/39Ar Dating Using the Geological Survey TRIGA Reactor. U.S. Geological Survey Professional Paper 1176.Google Scholar
Dalrymple, G.B., Lanphere, M.A., Pringle, M.S., (1988). Correlation diagrams in 40Ar/39Ar dating: Is there a correct choice?. Geophysical Research Letters 15, 589–591.Google Scholar
Duffield, W.A., Dalrymple, G.B., (1990). The Taylor Creek Rhyolite of New Mexico: A rapidly emplaced field of lava domes and flows. Bulletin of Volcanology 52, 475–487.Google Scholar
Fleck, R.J., Turrin, B.D., Sawyer, D.A., Warren, R.G., Champion, D.E., Hudson, M.R., Minor, S.A., (1996). Age and character of basaltic rocks of the Yucca Mountain region, southern Nevada. Journal of Geophysical Research 101, 8205–8227.Google Scholar
Gillespie, A.R., Huneke, J.C., Wasserburg, G.J., (1983). Eruption Age of a Pleistocene Basalt From 40Ar–39Ar Analysis of Partially Degassed Xenoliths. Journal of Geophysical Research 88, 4997–5008.Google Scholar
Gillespie, A.R., Huneke, J.C., Wasserburg, G.J., (1984). Eruption age of a ∼100,000-year-old basalt from 40Ar–39Ar analysis of partially degassed xenoliths. Journal of Geophysical Research 89, 1033–1048.CrossRefGoogle Scholar
Heizler, M.T., Perry, F.V., Crowe, B.M., Peters, L., Appelt, R., (1999). The age of Lathrop Wells volcanic center: An 40Ar/39Ar dating investigation. Journal of Geophysical Research 104, 767–804.Google Scholar
Hildreth, Wes, Fierstein, Judy, (1995). Geologic Map of the Mount Adams Volcanic Field, Cascade Range of Southern Washington. U.S. Geological Survey Map I-2460, scale 1:50,000.Google Scholar
Hildreth, Wes, Lanphere, M.A., (1994). Potassium–argon geochronology of a basalt–andesite–dacite arc system: The Mount Adams volcanic field, Cascade Range of southern Washington. Geological Society of America Bulletin 106, 1413–1429.Google Scholar
Ingamells, C.O., (1970). Lithium metaborate flux in silicate analysis. Analytica Chimica Acta 52, 323–334.Google Scholar
Lanphere, M.A., Dalrymple, G.B., (1976). Identification of excess 40Ar by the 40Ar/39Ar age spectrum technique. Earth and Planetary Science Letters 32, 141–148.Google Scholar
Lanphere, M. A., Dalrymple, G. B., (1978). The Use of 40Ar/39Ar Data in Evaluation of Disturbed K–Ar Systems. pp. 241–243. U.S. Geological Survey Open-File Report 78-701.Google Scholar
Lanphere, M. A, Dalrymple, G. B., (2000). First-Principles Calibration of 38Ar Tracers: Implications for the Ages of 40Ar/39Ar Fluence Monitors. U.S. Geological Survey Professional Paper 1621.Google Scholar
Lanphere, M. A, Champion, D. E, Kuntz, M. A., (1993). Petrography, Age, and Paleomagnetism of Basalt Lava Flows in Coreholes Well 80, NRF 89-04, NRF 89-05, and ICPP 123, Idaho National Engineering Laboratory. U.S. Geological Survey Open-File Report 93-327.Google Scholar
Mankinen, E.A., Dalrymple, G.B., (1972). Electron microprobe evaluation of terrestrial basalts for whole-rock K–Ar dating. Earth and Planetary Science Letters 17, 89–94.CrossRefGoogle Scholar
Merrihue, C., Turner, G., (1966). Potassium–argon dating by activation with fast neutrons. Journal of Geophysical Research 71, 2852–2857.Google Scholar
Sharp, W.D., Turrin, B.D., Renne, P.R., Lanphere, M.A., (1996). The 40Ar/39Ar and K–Ar dating of lavas from the Hilo 1-km core hole, Hawaii Scientific Drilling Project. Journal of Geophysical Research 101, 11,607–11,616.Google Scholar
Singer, B.S., Pringle, M.S., (1996). Age and duration of the Matuyama–Brunhes geomagnetic polarity reversal from 40Ar/39Ar incremental heating analyses of lavas. Earth and Planetary Science Letters 139, 47–61.CrossRefGoogle Scholar
Singer, B.S., Thompson, R.A., Dungan, M.A., Feely, T.C., Nelson, S.T., Pickens, J.C., Brown, L.L., Wulff, A.W., Davidson, J.P., Metzger, J., (1997). Volcanism and erosion during the past 930 k.y. at the Tatara-San Pedro complex, Chilean Andes. Geological Society of America Bulletin 109, 127–142.Google Scholar
Stacey, J.S., Sherrill, N.D., Dalrymple, G.B., Lanphere, M.A., Carpenter, N.V., (1981). A five-collector system for the simultaneous measurement of argon isotope ratios in a static mass spectrometer. International Journal of Mass Spectrometry & Ion Physics 39, 167–180.Google Scholar
Staudacher, Th., Jessberger, E.K., Dörflinger, D., Kiko, J., (1978). A refined ultrahigh-vacuum furnace for rare gas analysis. Journal of Physics E: Scientific Instruments 11, 781–784.Google Scholar
Taylor, J.R., (1982). An Introduction to Error Analysis. University Science Books, Mill Valley.Google Scholar
Turner, G., Cadogan, P.H., (1974). Possible effects of 39Ar recoil in 40Ar–39Ar dating. Proceedings, 5th Lunar Science Conference, Geochimica et Cosmochimica Acta Supplement 2, p. 1601–1615.Google Scholar