Strain transfer at continental scale from a transcurrent shear zone to a transpressional fold belt: The Patos-Seridó system, northeastern Brazil

An Update on "Paraíba" Tourmaline from Brazil

“…ago (van Schmus et al, 1995;Beurlen et al, 2000;Araújo et al, 2001). The pegmatites are confined mostly to the Seridó fold belt (Ebert, 1970;Corsini et al, 1991; again, see figure 2); more than 200 are known within an area measuring approximately 75 × 50 km that stretches southward from the town of Currais Novos . The majority of the mineralized pegmatites occur within the Seridó and Equador formations, which form much of the 30-km-long Serra das Queimadas range (Silva, 1993).…”

“…This continental-scale tectonic system extended into westerncentral Africa (around Nigeria), as these geologic events occurred prior to the separation of South America from Africa (see Trompette, 1994). Within the Borborema Province, rocks of the Seridó Group were folded into a series of northeast-trending anticlines and synclines that comprise the Seridó fold belt (Ebert, 1970;Corsini et al, 1991;Vauchez et al, 1995). Numerous granitic bodies and associated pegmatites formed during the latter stages of this orogeny, between about 510 and 480 m.y.…”

Microestruturas e tramas de eixo C de quartzo em milonitos do Sistema de Cisalhamento Campina Grande (PB), Província Borborema

“…No Seridó, por outro lado, a compressão dominante foi aproximadamente E-W atribuída ao movimento para leste do Patos (Corsini et al 1991) Este estudo é focado no conjunto de falhas transcorrentes situados entre o lineamento Patos e a zona de cisalhamento de São José dos Cordeiros, denominado "Sistema de Cisalhamento Campina Grande" (Fig. 2).…”

“…1). Nestes lineamentos são comuns milonitos de alta temperatura frequentemente associados a fusão parcial das rochas encaixantes (Vauchez & Egydio-Silva 1992, Corsini et al 1991. Milonitos de média e baixa temperatura e ultramilonitos são encontrados notadamente no Lineamento LestePernambuco (Davison & MacCarthy 1995, Neves et al 1996 e na borda sul do Lineamento Patos (Corsini et al 1991;Vauchez et al 1995).…”

Geocronologia de eventos magmáticos e mineralizações associadas no Precambriano da Faixa Seridó, Província Borborema

“…Details for analyt¡cal procedures and measurements are also given in Table 2. lnitial Nd isotopic compositions for all samples were calculated to their respective U-Pb ages (see Table 1 Some studies cons¡der that the migmatization is a Paleoproterozoic high-grade metamorphism (see Souza et al, 2008, and references therein), but there are growing evidences in NE Brazil and in Africa that at least part of the basement complex melted or reached the granulite facies 25 only in the Brasiliano-Pan African orogen (Pin and Poidevin, 1987;Corsini et al, 1991). (Fetter et al, 2000) suggesting that the whole domain to the north of the Patos shear zone would constitute a single crustal block.…”