Caracterização preliminar do subsolo da área urbana de Boa Vista-RR, a partir de sondagens de simples reconhecimento

Abstract

The State of Roraima one bes situated in the extreme north of Brazil. It has as capital the cityof Boa Vista and makes limits to the north with cities of Amajarí and Pacaraima; to the south with the cities of Mucajaí and Alto Alegre; to the east with the cities of Bonfim and Cantá. Considering all the urban construction of Boa Vista, the following variables had been studied: altitude, water level and limit of probing, objectify the preliminary characterization of the subsoil of Boa Vista through probing of simple recognition. Had been used 75 point whose 47 were from the data base of the company A.P Engineering and RC engineering in the year of 1994 to the 2007 and more 28 data raise during the research. Was accomplished the analysis of multivary for the knowledge of standard not supervised according to the technique of Analysis of Hierarchic Component confirm by the Analysis of the Major result. With this 3 Zones for the City of Boa Vista had been identified: Less Vulnerable; Zone 1 - only englobando the Cidade Satelite districts and Zone 3 - the Aquilino da Mota Duarte districts, Centro districts and its transecto until the Caçari districts, Caçari districts and Paraviana districts; More vulnerable: Zone 2 - all the districts located after the limit of BR 174, felt east, with exception of the Aquiline districts of the Mota Duarte and the districts between BR 174, Center, Caçari and Paraviana. The average of the water Level (In) of the city was of 6,3m, the districts with bigger curve of level if they had fit in the districts of little vulnerability; in the points Cecília Brasil, Cel Mota, Ig Mirandinha, Av Gen Sampaio they had registered In the one in the surface; the ground most resistant was the point Center SEFAZ, in the Center districts with limit of sounding of 1,1m, the ground with lesser resistance was located point BR 174 in area of after closed the bridge of the Cauamé. After the determination of the zones and less vulnerable was carried through a granulometria analysis to represent each zone, that classified the material of the point more vulnerable as frank sand and frank arenaceous and for the representative point of the zone less vulnerable it presented the classification of the material as frank argilo arenaceous and frank arenaceous. Therefore, has the necessity of if evaluating the potentially polluting activities of underground waters as localization of cemeteries, in the septic construction of sewerage system and the monitoring of fuel ranks. Thus, the results of this work will serve as plus ambient indicatives for a taking of decisions of public politics, considering the economic, social and ambient factors.