Pre-Tertiary dunite intrusive rocks (WApTd;0)

State	Washington
Name	Pre-Tertiary dunite intrusive rocks
Geologic age	Middle Jurassic
Original map label	pTd
Comments	Huntting and others, 1961, does not map any WApTd unit on Mount Chopaka (there is WApTb, however, which contains peridotite).
Primary rock type	dunite
Secondary rock type
Other rock types
Lithologic constituents	Major Igneous > Plutonic > Ultramafic > Peridotite > Dunite
Map references	Huntting, M. T., Bennett, W. A. G., Livingston, V. E. Jr., Moen, W. S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000.
Unit references	Huntting, M. T., Bennett, W. A. G., Livingston, V. E. Jr., Moen, W. S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000. Dragovich, J. D., Logan, R. L., Schasse, H. W., Walsh, T. J., Lingley, W. S., Jr., Norman, D. K., Gerstel, W. J., Lapen, T. J., Schuster, J. E., Meyers, K. D., 2002, Geologic Map of Washington-Northwest Quadrant: Washington Division of Geology and Earth Resources Geologic Map GM-50, scale 1:250,000.
Geographic coverage	Skagit