O desgaste da pintura rupestre e dos abrigos sob rocha na reserva particular do patrimônio natural (RPPN) Pousada das Araras em Serranópolis-Goiás: condicionantes naturais.

Abstract

Present study analyzes Natural Conditionants responsible to decay rock paintings in caverns. Two archaeological sites named GO-JA-03 and GO-JA-04 were selected. Chosen areas are situated on a Particular Reserve of Natural Patrimony (RPPN), Inn of Araras (Macaw Inn) on Serranópolis, a city located 450 Km distant from Goiânia, at Southwest of Goiás, Brazil. Both archaeological sites are ancient rock paints representations of Botucatu Rock Formation. First site is a cave with 80 meters length to 64 meters height and 6 to 14 deep known as Grotto of Araras. Second site is a small cave with 10 meters length to 8 meters height named Grotto of Paredão (Great Wall Cave). Serranópolis City area roused researchers and archaeology students due to rock paintings and figures that covers sandstones caves and present ancient human occupation, dated from 11 thousand years B.P. to XX century. These sites are one of the most important and riches from Brazil to study human arrival and hunters populations from Holocene period. These areas are 500 to 900 meters height from sea level and have rock shelters localized in Botucatu Sandstone that represents thick archaeological layers and walls decorated with paintings and figures (SCHMITZ et al, 2004). It analyzes it of the processes of intemperism in the shelters of the Inn of Araras evidences that the physical, chemical factors and biological they must be seen in set, a time that has association of these factors, being able to be treated as factors of intemperismo. The existing forms of physical imtemperism are relief of pressure, crystallization and thermal expansion. The disintegration of the rock is a factor of extreme relevance as for ruspestres paintings, a time that is represented in a film of the easily erodivel rock. The breakings originated for the temperature variation, easily identified in the area of the Inn of Araras, are one of the main factors of comprometimento of rupestres paintings and the stability of the shewlters. This breakings make possible occurrence of movements for gravity, of falls of block (blocks that if they unfasten of the bulk in free fall), falling of blocks (it is characterized for the rotation of the block in fall) and desplacamento (characterize for the unfastening of chips or plates of rocks). The characteristic rections of the chemical intemperism as hidratação, dissolution, hydrolysis, oxidation and acidólise are not treated separately, but yes in set. The pluvial waters, in the context of the shelters can destroy paintings or to mask the original pigmentação from the leaching processes that promote the formation of spots or horozontes with the colors esmaecidas and claras. The biological factors they are enclosed those related the vegetation, such as seaweed, liquens, mosees, bacteria, raízes and plants and also those related the action of animals (insects, bats, birds and rodents). The microbianos processes can provoke the degradation of the rocks, modifying amongst other factors, the solidity and the permeability of the rock. The identified factors of the intemperism in grottos are boarded in biological, chemical and physical as the intensity of occurrence. In function of the tourist potencial of the region, wll have to be developedactions come back toward the protection grottos and rupestrian painting,associating them it the structural conditioning of the area, demanding a boarding to muitidiscipline and specific financial tesources toward the preservating of grottos. The measures of protection to be acquired for the preservation of grottos must be developed by a team to muiltidiscipline, counting on the support of the public power and still of the private sector.