Portal de Periódicos da CAPES

Estudo das feições estruturais e tectônicas do nordeste do estado de São Paulo e sudoeste do estado de Minas Gerais através da gravimetria

2003; Linguagem: Inglês

2639-6459

Maximilian Fries,

Geophysics and Gravity Measurements

A geophysical survey have been carried out at northeast of Sao Paulo State and Southwest of Minas Gerais State (an area 80 km wide and 97,5 long) in Brazil. The Bouguer anomaly map, geological and structural data allowed to identify three different gravity domains related to the structural features (crustal blocks limited by major discontinuities) in the area. These discontinuities interpreted as geosuture zones lying under the Parana Basin sediments have its extend in the Pre-Cambrian Basement. The crustal discontinuities named Alterosa and Ribeirao Preto. Pre-existing datas were previously taken before the new datas were colected. Gravity data indicate a gravimetric high (less negatives Bouguer values) in the southwestern sector of the Bouguer anomaly map.Two linear proeminent positive anomalies are recognized in the Bouguer anomaly map.The limit between the Brasilia and Sao Paulo crustal blocks or paleoplates, the Alterosa suture zone is in a NW-SE trend. Perpendicular in a NE-SW trend is the Ribeirao Preto suture. The distribution and the shape of the two crustal blocks suggests a low-angle overthrusting of the Sao Paulo block on the Brasilia block. The produced Bouguer anomaly map provides information and understanding of the concepts and theories for future tectonic models and geologic evolution in the area.