ANOMALIES IN PATTERNS OF NETWORK DRAINAGE HOW FACTOR FOR VERIFICATION OF NEOTECTONIC – A CASE STUDY IN THE SUB-BASINS OF MAMUABA RIVER – PB

Abstract

This work presumes to argue about the importance of anomaly analysis of patterns drainage networks in neotectonic studies. To check such anomalies were used how primary instruments the indexes SL (Relationship Slope-Length) and VF (Reasion Valley Floor/Valley Height), these indexes will be used for the geologic-geomorphologic analysis of sub-basins and for detection of neotectonics evidences associated the anomalies found in the current patterns drainage. For this analysis were selected the Jangada, Mundo Novo e Grilo sub-basins, they are seated on same litology – the Formação Barreiras - layer of poorly consolidated sedimentary rocks of Miocene age, which settle more or less horizontally. Cuz these sub-basins present their atypical drainage patterns to your geology, such as straight  rivers and asymmetrical shapes, appear the need of checking the geomorphological processes that conditioned the evolution this watershed. The application of morphometric indices RDE and RFAV resulted in values that indicate that the area over which the sub-basins are located, probably suffered recent tectonic activity.