The drainage basin analysis is important in any hydrological investigation such as study of hydrologic processes, management of wetlands, flood, erosion and landslides susceptibility studies, assessment of groundwater potential and groundwater management. Also, existing theories and models such as the laws of drainage composition can be verified. In the light of the foregoing, the present paper describes the drainage characteristics of the lower Enyong Creek, which is underlain by varying geologic formations. viz; Asu River Formations e.g the Abakiliki Anticlinorium to the recent alluvium in the south It involved detailed map-based quantitative analyses of two 4th order sub-catchments in the study area. The drainage pattern is mainly dendritic type. It is observed that the drainage density value is low which indicates the basin is highly permeable subsoil and thick vegetative cover. The elongation ratio value reveals that the basin is strongly elongated and stream abstraction process constrained by heterogeneous geologic materials. This study would help the local people to utilize the resources for sustainable development of the basin area.

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Landslides are ubiquitous geomorphic features in the loose/weakly cemented soils formed from the coastal plains sands in different parts of southeastern Nigeria due to widespread gully erosion resulting from infrequent occurrence of high intensity and prolonged rainstorms during the peak of wet season (June-September). In this area, landslides occur mostly as earth movement, mud flow, and debris flows on slopes previously weakened by flood water. GIS (Geographic Information System) was employed as a system with advanced geo-modeling capabilities combined with field observation which were used in this study to map potential areas of landslides in Uyo town, Akwa Ibom State in southeastern Nigeria. The study generated a landslide zonation map highlighting areas of different degrees of susceptibility elevation in meters. Slope surface in degrees was also generated and reclassified into three slope classes (uniform, gentle and steep) using the same reclassification algorithm. The result indicates that 89,583 m 2 representing 10.59% of the total catchment of 845,918 m 2 is highly susceptible to landslides.

In south-eastern Nigeria, gully erosion has assumed an alarming proportion and this prompted the use of geospatial information technology to map a gully erosion site in Oron, Akwa Ibom State for effective remediation and control.,. Ground controls were provided in the vicinity of the gully head through the use of dual frequency Leica GPS 1200. The obtained data were downloaded and processed using Leica Geo Office 8.3 and the processed data exported to Arc GIS 10.1 and Auto CAD Civil 3D 2013 for terrain analysis-DEM , Also, the Leica Total Station TS 06 was employed to carry out topographic mapping. The delineated runoff contributing area aided in the computation of maximum discharge (using the Rational method). The computed runoff of 33.919m 3 /s accounts for the rapid rate gully headscarp retreat at the rate of 1.2m/day during the month of July, prior to intervention by the state government. The results obtained were employed in designing gully control structures.