Montesano Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Cenozoic
 ...Neogene
 ....Miocene
 .....upper Miocene
 ......Montesano Formation
RTWashington
SNLargely massive coarse-grained light-brown sandstones, with many intercalated lenses of conglomerate and grit; shales subordinate in lower part but common in upper part. SW and NW Washington.