Mesozoic-Tertiary volcanic rocks, undivided

Altered basalt, pillow lavas, and flow breccia of inner volcanic belt of Olympic Peninsula; includes minor interbedded red limy argillite and associated manganese ore.
State Washington
Name Mesozoic-Tertiary volcanic rocks, undivided
Geologic age Oligocene to Eocene
Lithologic constituents
Major
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow, Volcaniclastic-volcanic breccia, Pyroclastic-tuff)
Minor
Metamorphic > Metaigneous > Greenstone (Zeolitic (prehnite-pumpellyite))
Sedimentary > Clastic > Sandstone (Bed)
Incidental
Igneous > Plutonic > Gabbroic > Gabbro (Dike or sill)
Metamorphic > Metasedimentary > Metaclastic > Argillite (Zeolitic (prehnite-pumpellyite))Protolith possibly limestone listed by Dragovich and others, 2002.
Igneous > Plutonic > Dioritic > Diorite (Dike or sill)
References

Huntting, M.T., Bennett, W.A.G., Livingston, V.E.Jr., and Moen, W.S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000.

Tabor, R.W., Yeats, R.S., Sorensen, M.L., 1972, Geologic Map of the Mount Angeles Quadrangle, Clallum and Jefferson Counties, Washington: U. S. Geological Survey Geologic Quadrangle Map GQ-958, scale 1:62,500.

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.

Tabor, R.W. and Cady, W.M., 1978, Geologic Map of the Olympic Peninsula, Washington: U. S. Geological Survey Miscellaneous Investigations Series Map I-994, scale 1:125,000.

NGMDB product
Counties Clallam - Grays Harbor - Jefferson - Mason