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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Lyon Mountain Gneiss
  • Modifications:
    • Geochronologic dating
  • AAPG geologic province:
    • Adirondack uplift
Publication:

Rankin, D.W. (editor), Chiarenzelli, J.R., Drake, A.A., Jr., Goldsmith, Richard, Hall, L.M., Hinze, W.J., Isachsen, Y.W., Lidiak, E.G., McLelland, James, Mosher, Sharon, Ratcliffe, N.M., Secor, D.T., Jr., and Whitney, P.R., 1993, Proterozoic rocks east and southeast of the Grenville Front, IN Reed, J.C., Jr., and others, eds., Precambrian; conterminous U.S.: Geological Society of America, The Geology of North America, The Decade of North American Geology (DNAG), v. C-2, p. 335-461.


Summary:

U-Pb zircon ages for Hyde School Gneiss indicate that it crystallized around 1285 to 1230 Ma. U-Pb zircon ages for lithologically similar Lyon Mountain Gneiss indicate crystallization around 1080 to 1050 Ma. Despite similar appearances, the two gneisses are of a different origin. [Information is from section by J. McLelland and others, within chapter 5.]

Source: GNU records (USGS DDS-6; Reston GNULEX).


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

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