The Paraná Magmatic Province: State-of-the-Art in the Geophysical and Geochemical Investigations

Abstract

This paper presents an overview of the present knowledge on the Paraná magmatism and the lithospheric structure under the Paraná Basin. The genesis and diversity of the flood basalt types are linked to the structure and tectonic processes that have affected the crust and upper mantle since the Western Gondwana amalgamation until subsequent rupture. It focuses mainly on the work developed at the Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de São Paulo (USP), during five decades, starting from the first detailed paleomagnetic data acquisition along vertical profiles and then associated with the chemical data, a pioneering initiative in the world. Chemical and isotope data were then acquired substantially, allowing advanced knowledge of the sources and genesis of the different magma types. The geophysical studies, including gravity, seismology and electromagnetic induction methods, allowed the recognition of crustal and lithospheric structures and rheology below the sedimentary basin, giving evidence for the magma generation models. Although the aspects addressed here do not run out the subject, it summarizes essential aspects of the present knowledge of the Paraná Magmatic Province.