Reconnaissance map showing relative amounts of soil and bedrock in the mountainous part of the Pinewood Lake-Carter Lake Reservoir quadrangles, Boulder and Larimer counties, Colorado

This map shows the relative amounts of soil and hard bedrock within the upper 6 feet (1.8 m) of the land surface.  (See schematic section.)  It provides information useful for broad-scale land-use decisions.  The map is based on reconnaissance field studies and aerial-photograph interpretation.  The depth of soil and weathered rock was measured directly in roadcuts and other excavations and was estimated from seismic profiles in areas of few or no excavations or outcrops.  Secondary characteristics of map units, such as percentage of outcrop in a given area, steepness of slope, type and amount of vegetation cover, and general appearance of the landscape, were used in drawing the boundaries between map units.  Localities were assigned to the different map units by field inspection; lines separating the different map units were then drawn by aerial-photograph interpretation and were transferred photogrammetrically to the base map.