Evaluation of Pedological Variables as Subsidy for Interpretation of Geomorphological Surfaces’ Time in Marine Depositional Systems of Damp Tropical Climate

Abstract

This research aimed to evaluate the efficiency of the pedological method (applied in fluvial systems) by Perez Filho et al. (1980), in marine depositional systems. Therefore, it aimed to verify if the values of the variables obtained (CEC, BS%, silt/clay and fine sand/coarse sand relation) are matching with the degree of weathering of the surface materials and probable time of the geomorphological surfaces, from correlations based on the altimetric position of the forms elaborated in coastal systems. It was verified that the methodology adopted by Perez Filho et al. (1980) on fluvial terraces proved to be coherent, however, it became inefficient for the analysis of elaborated geomorphological levels in marine systems. It was observed that the only level that presented pedogenetic processes of pedological maturity and advanced chemical weathering of primary minerals corresponds to the geomorphological surface I. At levels II and III it was not verified the performance of the soil formation factors, recent sedimentary deposition was observed, constantly reworked by erosive / depositional coastal dynamics, fact that made it impossible to development of a pedogenetic profile according to the soil concept used by the pedological literature. Differently from the method applied by Perez Filho et al. (1980), in surfaces elaborated in fluvial systems, where the only variable that did not correlate with the time of the geomorphological surfaces and degree of weathering of the materials referred to the relation of fine sand /coarse sand, the application in marine depositional environments evidenced inverse situation.