Mapeamento geológico de uma área localizada a oeste do arco magmático de Santa Quitéria no município de Ipaporanga-Ce para fins prospectivos de minério de Fe

Abstract

The geological mapping carried out in an area west of Magmatic Arc of Santa Quitéria, in the Ipaporanga city, scale 1:25.000, allowed to characterize an extrernely important metallogenic environment, propitious to generating hydrothermal iron deposits, in particular the type IOCG (Iron Oxide-Copper-Gold). The lithostratigraphic point of view it was identified also a new Precambrian Unit, the Estreito Metavokanic Unit, recognizing, from bottom to top, the following units: Ceará Complex — Canindé Unit, Estreito Metavolcanic Unit, Tamboril-Santa Quitéria Complex, Serra Grande Group, Basic Dikes and Cenozoic Deposits. The iron ore occurrences are basically developed at the contact between metarhyolite and andesitics meta-basaltic as well as meta-diorite albitized, embedded in pelitic gneisses with garnet and cale-silicate rocks, cut by biotite gravite, gabbro and diorite porphyritic. The assembly is partially covered by Paleozoic sedimentary rocks of the Parnaíba Basin, which may have preserved partly the mineralization. The different occurrences of ore minerais are classified into four distinct typological associations: ore Fe- P stratabound, disseminated Fe, iode Fe and massive magnetite ore skarn type. Such associations lead us to think of a training mechanism, or a complex story of mineralization and metasomatic changes.