Sedimentary and volcaniclastic rocks (ORTus;0)

Lapilli tuff, mudflow deposits (lahars), flow breccia, and volcanic conglomerate, mostly of basaltic to dacitic composition; rare iron-stained palagonitic tuff and breccia of basaltic and andesitic composition; and ash-flow, air-fall, and water-laid tuff of dacitic to rhyolitic composition. The palagonite tuff and breccia grade laterally into peperite and into lava flows of basalt and basaltic andesite

State	Oregon
Name	Sedimentary and volcaniclastic rocks
Geologic age	Tertiary
Original map label	Tus
Comments	assorted rocks
Primary rock type	sedimentary rock
Secondary rock type	pyroclastic
Other rock types	tuff
Lithologic constituents	Major Sedimentary > Clastic (Bed) Minor Igneous > Volcanic > Mafic-volcanic (Pyroclastic, tuff) Incidental Igneous > Volcanic > Felsic-volcanic (Volcaniclastic) Igneous > Volcanic > Felsic-volcanic (Pyroclastic, tuff) Igneous > Volcanic > Mafic-volcanic (Volcaniclastic, lahar)
Map references	Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000.
Unit references	Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000.
Geographic coverage	Clackamas - Douglas - Jackson - Lane - Linn