This dissertation, developed within the context of the PRONEX Project of the Environmental Geotechnical Center of PUC-Rio and through a FURNAS-PUC-Rio Convenium, presents a contribution towards the identification and comprehension of mechanisms involved in erosion processes, considering its geological and geotechnical aspects as well as preventive repairing measures in the case of a specific gully formation. The evolution of the studied erosive process has its origin in the mechanical removal of some five meters of a clayey soil layer from a borrow area exploited at the time of the construction of an homogeneous embankment dam belonging to the Itumbiara Hydroelectric Complex. The main aspects of the studied area, such as its location, climatic conditions and soil and vegetation types were considered in the development of the work, besides regional geological aspects and geological-geotechnical features of the area affected by the erosion processes. Taking as a basis the unsaturated weathering profile identified by inspection of the walls of the gully formation, as well as of samples from SPT (standard penetration test) boreholes, four types of soil layers were taken as representative of site conditions. Aiming the identification, classification and definition of the erodibility potential of such materials, specimens from undisturbed block samples (as well as remolded ones) were submitted to laboratory investigations comprising: conventional soil characterization tests; MCT characterization test (mini-MCV); crumb test; desegregation test; pinhole test; Inderbitzen test, permeability tests (also performed in the field); chemical analysis (both soil and voids -water); mineralogical analysis (Xrays diffraction); tensile strength test (under different saturation conditions) and filter paper test (for definition of soil-moisture characteristic curves). Based on the results of the laboratory tests, field observations and data from pore-pressure monitoring (through piezometers installed in the site), erosion mechanisms that may prevail in the area were defined as micro-rills, rill, gully and others. Also, at the end of the work, are presented suggestions for remediation of the site, considering corrective measures used within the context of conventional geotechnical practice, and a methodology to be followed in further investigations related to the characterization of the site and development of erosion processes.