 Activity picked up during the Quaternary period in Washington, as andesitic stratovolcanoes and small, olivine basalt cinder cones and shield volcanoes erupted.Before the Pleistocene, uplift and erosion was widespread, which was followed by eruptions from the northeastern part of the Wind River area during the early Pleistocene.Rocks in the Wind River area have not been altered significantly by orogenic movement (large structural deformation of the Earth's crust and uppermost mantle due to the interaction between plate tectonics).