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. . . SOILS REPORT A~ID MAP OF PROPOSED MARBLE SKI AREA 7-7-71 At the request of the Regional Forester, a reconnaissance made on the proposed ~larble Ski Area. Because of snow on lack of time, only the lower ski lift line was examined. map was made by some field sampling, photo interpretation ical Survey Map. soil survey was the ground and the The general soils and a 1960 Geolog- ! t ; I I , I I I i I This soils report, map and interpretation table should be used only for evaluating the soils in broad planning. They can be useful, however, in 'pointing out certain areas that may have severe limitations because of certain soil ,properties. The soil map and interpretive rating will provide data that can be used, for example, in planning fertile areas for reseeding highl~ erosive soils and landslide areas. Onsite investigations must be made where detailed information is needed on such jobs as roads, building sites, lift towers, etc. Mount Daly is composed of mostly granodiorite with some scattered remnants of sedimentary rocks. The upper study area is rugged and the highest point reaches.an elevat,ion of more than 12,600 feet. The gorges that are on both sides of the ski area are the result of severe glaciation and are as imposing as the peaks and serrated ridges. The deep gorges usually head in cirques with'large accumulations of talus from the oversteepened cliffs. I ~-; ,The main study area lies in a high basin-like area at elevations ranging from 8,800 to 10,400 feet. Soils in this moderately steep rolling terrain are a mixture of outwash, glacial and colluvial material that caps Mancos shale. Both Carbonate Creek and North'Fork have cut deep canyons exposing the gray Mancos shale along the mountainsides. The vegetation at the base of the ski lift and the main ski slope is mostly tall aspen and grass. Soils under this heavy vegetative cover are deep, dark, fertile and very productive. Subsurface water that is moving between the glacial material and shale can make this area susceptible to landslides. There are signs of small old soil slumps near springs and wet areas. It is important to avoid steep cuts, impounding of water or adding excess water to these soils. Slump areas should be thoroughly checked before any large structures are constructed. There are three major soil types that occur' on the ski slopes of Mount Daly. Although other soil types and phases are mapped, the three most sig- nificant are the glacial covered uplands; shallow residual shale soils and stony inactive soil-mantled talus. Soil Unit / 314 I Soils in this unit are found at higher elevations and are charac- terized by shallow soils and steep slopes. These soils are gen- erally stony, shallow to bedrock and include some exposed bedrock, talus, slope wash and soil-mantl~d talus.