Geological and Geotechnical Assessment of Selected Gully Sites in Wuro Bayare Area NE Nigeria

An assessment of the geological and geotechnical parameters as causative agents in the formation of gullies in Wuro Bayare area of northeastern Nigeria is presented. Field geological study of the study area revealed that the area is underlain by basement rocks. The soils in the area are product of in-situ weathering of the underlying basement rocks. The results of sieve analysis shows that the soils at the gully sites have sorting values ranging between 0.42 and 2.3, coefficient of uniformity values ranging between 0.02 and 200, coefficient of curvature values ranging between 0.0125 and 0.23 and also the constanthydraulic values (Kvalues) is use to know the bottom erosion ranges. These indicate that the soils are poorly to well-sorted in places. The plasticity indices values ranges between 9.9 and 5.5 with a mean value of about 20 indicates soils of moderate to highly plasticity, slight dry strength and easily friable. Values of Maximum Dry Density (MDD) ranging between 2.15 and1.83 g/cm3 at Optimum Moisture Contents (OMC) of between 12.4 and 6.4% reveals that the soils were generally lose. From the geotechnical analysis results, commendations for erosions control such as; construction of drainages, grouting concrete rip-raps and afforestation were suggested.