Planation surface in humid subtropical morphoclimatic zone in the Basaltic Plateau of Parana Basin (SW Parana and NW Santa Catarina): First Approach

Abstract

This article presents planation surfaces identified in humid subtropical morphoclimatic zones, in the Basaltic Plateau of Parana Basin – SW of Parana and NW of Santa Catarina. It has proceeded: a) descriptions of superficial formations in the field, checking its autochthonous or allochthonous genesis; b) spatial distribution of surfaces in hypsometric classes with equidistance of about 100 m, from a mosaic generated with the orbital sensor Shuttle Radar Topography Mission data. It has been identified eight of reminiscences planation surfaces organized in layers from the west to east, with even three levels inlaid, among the hypsometric classes of 1.400 to 600 m and surfaces in formation in quotes > 600 m, in the form of shoulder pad in the button of the valleys. It is thought that the surfaces were formed simultaneously and tectonics factors have been very important in the formation of landforms in layers. It is proposed the hypothetic evolutive model for the planation surfaces of the area. It has been observed that: a) the planation surfaces have developed by etch processes; b) the kind of the lava flow has little influence on the development of planation surfaces; and c) the kind of subtropical climate had a very important role on the planation morphology of the surfaces in the area of study, even against the climate changes registered in the Cenozoic era.