An introduction and GIS-based relief compartment mapping of fluvio-karst
landscape in central Brazilian highlands
Abstract
The present work is part of a greater research project aiming at
creating knowledge-base for the future managerial plans dedicated to the
protection of caves heritage in the Correntes Basin (3904 km 2) located
in the central Brazil. Here, a GIS-based relief compartment mapping of
the area is done using satellite images, geological map and cave
location map as input data layers. As a result four geomorphological
domains were identified as i) lowlands (282 km 2) with a base-level in
silicates and carbonates, ii) the karst terrains (994 km 2) which were
developed in carbonates trapped by siltstone lenses iii) the talus (1483
km 2) having colluvial and alluvial units deposited by the Urucuia
escarpment retreat and iv) the highlands (1143.7 km 2) developed over
the sandstone of the Urucuia Group. The intersection of landforms and
geological maps resulted in two abrupt contacts, the first between
lowland and karst terrains, and second between the talus and highlands
which formed canyon and escarpment, respectively. Two types of the cave
systems are proposed in the region as superior/vadose that collect
floods from hillslopes and deep epigene fluvio-karst.