Abstract

The Japi Complex, in the eastern gneiss-migmatite domain of the Serido Belt (NE Brazil), is a composite, en comae-shaped intrusive body, comprising an older syntectonic alkalic granite and late, syn- to late-tectonic basic-to-intermediate shoshonitic plutons and granitoids of monzonitic and calc-alkalic affinities. A persistent control on the emplacement of the various suites by a nearby oblique, strike-slip + extensional is suggested by several features. Among them are: shapes of individual intrusions and their location in transtensional sites; metricto decimetric-thick sheets emplaced along shear bands, fold axial surfaces and semi-brittle to brittle pull-apart and transtensional jogs and transitions between viscous- to solid-state fabrics in the plutons, bearing the same orientation and kinematics as in their country rocks. This structure, the so-called Japi shear zone, is correlated to the main, high-temperature stage of the Brasiliano orogeny in this region.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call