The entire surface of the eastern plains is composed of alluvial sediments of Andean origin (Goosen 1964, Brunnsch-Weiler 1972), within the plains you can distinguish wide geological regions: to the north and west of the river Meta, there is marine deposit resent of age pleistocenica, and to the south and east lies the altillanura, expansive sediments of superior tertiary and lower quaternary origin (Ingeominas 1976.
The distribution of the soils is presented in accordance with the subdivision by large landscapes. The most important for their extension are Paleudutls - Paleustults, Haplorthox, Dystropept and Quatzipsamment, in well drained areas, and Plintaquept, Tropaquepts, Tropaquents and Umbraquox in areas with poor drainage. 
Four soil degradation processes have been described in the area, namely: surface compaction by trampling cattle, laminar erosion, in well-drained soils; reticular erosion, in the poorly drained soils of the basins in the alluvial overflow plain and solifluxion phenomena in areas covered by loess mantles (Botero 2003). 