A glacial basin was found in the Sousas area, Campinas County, surrounded by pre-Cambrian rocks and not connected with the Paraná sedimentary basin which possesses a similar formation. Geological studies were carried out consisting of petrographie identifications, structural sketch of the basin, delimitation of its occurrence, and mapping of its geological limits. The field delimitation was done by means of aerial photographs (average scale 1:14, 000) and topographic maps (scale 1:5, 000). The pedological studies that were performed consisted in taking soil profiles for morphological and genetic characterization of the great soil groups and collection of samples for textural analysis.