Figure 4: Digital elevation model of the Idaho Falls area showing eolian and other landforms: 1) basalt flow with age of ~557 ka covered with >20 m of loess ranging from at least 75 ka to 16 ka (Fig. 3); the edifices to west are shield volcanoes; 2) late Pleistocene lava flow covered with 4 m of loess of entirely Pinedale age (~25-16 ka); 3) young lava flow (6 ka) with almost no loess cover; 4) fill-cut terraces along the Snake River with <0.5 m of loess; the terraces were incised into Pinedale-age outwash deposits between 14.4-12.6 ka; 5) hairpin sand dunes sourced from 17.4 ka Bonneville Flood deposits near American Falls; inset shows enlargement; dunes at northern end are <1 ka and overlie loess-covered outwash deposits 6) Pleistocene Menan Buttes tuff cones elongated parallel to dominant modern wind direction; 7) braid-plain fan of Pinedale-age outwash deposits; these deposits are covered with <1.3 m of loess.
Image 17224 is a 1275 by 1694 pixel WebP
Uploaded:
Oct30 09
