Magnetic fabrics and rock magnetism of Proterozoic dike swarm from the southern São Francisco Craton, Minas Gerais State, Brazil

Magmatism, rifting and sedimentation related to Late Paleoproterozoic mantle plume events of Central and Southeastern Brazil

“…70% of the K max inclination values oscillate between 0 and 25 • for normal and intermediate AMS fabrics (Raposo et al, 2004). Dyke/wall rock contact features presented in Fig.…”

Radiometric ages, aeromagnetic expression, and general geology of mafic dykes from southeastern Brazil and implications for African–South American correlations

“…The AMS data (Raposo et al, 2004) and probable dykewall rock contact features (Chaves, 2001) gathered for this swarm seem to reveal subhorizontal magma flow from NW to SE, which suggests a magma source (mantle plume?) located northwest of the study area.…”

“…The anisotropy of magnetic susceptibility (AMS) data, obtained by Raposo et al (2004) for the Pará de Minas dykes, reveal subhorizontal magma flow; approximately 70% of the K max inclination is between 0 and 258 for normal and intermediate AMS fabrics. Dyke-wall rock contact features, such as centimetric magma branches with horn shapes and similar trends in the wall rock, point to magma flow from NW to SE and seem to confirm the subhorizontal flow (Chaves, 2001).…”

Separation of paramagnetic and ferrimagnetic anisotropies: A review

“…The remanence of the IRM is measured and then removed by AF demagnetization on a peak field higher than the DC field, which ensures a perfect cleaning of the artificial magnetization. The applied DC field is usually in the range of 10–60 mT [ Stephenson et al , 1986; Cagnoli and Tarling , 1997; Robion et al , 1999; Raposo and Egydio‐Silva , 2001; Hrouda , 2002; Raposo et al , 2004]. The DC field can also be applied in opposite directions successively.…”