Quaternary geology investigations in the Coal River map sheet (NTS 95D) during the 2009 field season focused on characterizing surficial materials and their distributions, with attention to the eastern half of the map sheet which has not been previously mapped. Moraine deposits are relatively thin in valley bottoms (<2 m) and become thinner and more intensely colluviated on upland surfaces. Streamlined glacial landforms and till plains are pronounced in the southern half of the map sheet. Surficial deposits are limited in many east-trending meltwater canyons, and in the northeastern corner of the map sheet.
The map area was glaciated most recently by the Cordilleran Ice Sheet, which advanced from the south and west. Meltwater from montane glaciers and the Laurentide Ice Sheet in adjacent map sheets likely contributed to extensive glaciolacustrine, glaciofluvial and glaciodeltaic deposits in north-trending valleys that were dammed by the Cordilleran Ice Sheet.
