Jornal de Geologia e Geofísica
Acesso livre

Abstrato

Geology and Structural Evolution of Neoproterozoic Rocks of Guliso Area, Wollega Western Ethiopia

Dereje Kenea

The research was conducted in the Guliso area, to study the petrography, metamorphism, structures and to construct a detailed geologic map of the area. The focused area was manifesting the sequences of eastern high-grade gneisses, central metamafic-ultramafic, and western low-grade metavolcanic-sedimentary rocks. The systematic field works and petrographic studies were used to detail identifications of the lithology and mineral assemblages that constitute the rocks of the area. Guliso area is characterized by high-grade gneiss, serpentinite-dunite, talc-chlorite schist, and granitic and gabbroic intrusions. Petrographic properties of the metasedimentary, metavolcanic, metaultramafic, gneiss, and migmatite gneiss rocks of the Guliso area suggested that these rocks have undergone low-grade to highgrade metamorphism up to greenschist facies. Whereas the abundance of mineral assemblages such as hornblende, amphibole, and biotite in gneiss and migmatite gneiss indicate that the rocks of the area also underwent highgrade metamorphism of amphibolite facies. The findings were also proposed three phases of deformations which is correlated with the previous classification, and all geological resources related to the geology of the area were indicated the good potential of metallic, industrial minerals, and construction materials.