Produção Nacional
Revisado por pares
Gravity interpretation and possible regional significance of the Niquelândia layered basic-ultrabasic complex, Goiás, Brazil
1991; Elsevier BV; Volume: 4; Issue: 4 Linguagem: Inglês
10.1016/0895-9811(91)90006-7
ISSN1873-0647
AutoresTomás Feininger, J.J. Dantas, Vicente Antônio Vitório Girardi,
Tópico(s)Geological formations and processes
ResumoAbstract The Niquelândia layered basic-ultrabasic complex is one of several similar Precambrian massifs that constitute a discontinuous, north-trending chain 300 km long through the central Brazilian Shield in the State of Goias. Modeling of the positive gravity anomaly associated with the complex indicates that the complex constitutes a westward-dipping slab that extends no deeper than 6 km. This model is similar to that obtained for the Barro Alto complex, the next massif to the south. The Niquelândia and Barro Alto complexes occur on a hinge line or gradient in the regional gravity field marked by paired Bouguer anomalies: residual highs to the west, lows to the east. The massifs may indicate a suture in the central Brazilian Shield marked by vast layered intrusions emplaced in continental rocks at the onset of an episode of rifting. Subsequent compression thrust remnants of the intrusions eastward, an event that may have accompanied the closing of an ancient ocean.
Referência(s)