Geosciences and Geophysics

Biography

Biography: Vinod K. Singh

Abstract

The mafic-ultramafic, banded iron formation, felsic volcanics, and granites have recognized as Archaean formation in the Bundelkhand craton. Two generations of felsic volcanics are found in Mauranipur and one in Babina greenstone belt, the central part of craton. The zircons separated from Mesoarchaean felsic volcanics from Mauranipur belt have ages 3242±65 Ma and 2813±20 Ma. The oldest zircon grains are interpreted as xenocrystics captured from pre-existing rocks whereas the second zircon group reflects the magmatism for continental crustal growth in Mauranipur belt. The second generation of felsic volcanics occurs in Babina belt during the Neoarchaean (2542±17 Ma). This volcanics correspond in composition to calc-alkaline dacites and rhyolites, indicating a subduction-related origin at an active continental margin. The Sm-Nd model ages (3.14 Ga) from volcanics of Babina belt indicate contamination of ancient crustal material. The young ages of 2531±21 Ma, 2516±38 Ma, and 2514±13 Ma magmatic crystallization age for pink granite in Babina area, suggest last stage of comprehensive reworking of continental crust of the craton during accretion -collisional events. The potassium-rich granites classified as mostly calc-alkaline in nature and having high silica 71.84 to 74.86 wt. %. In the Harkar diagram granites show the positive correlation of K₂O versus SiO₂ suggests that K-feldspar fractionation an important differentiation process during the late stages of crystallization for the granite. On the discrimination diagrams, the granites plot in the field of syn-collision to post-orogenic and A-type characteristics also indicates that it formed during syn-to post tectonic setting. 

The works began under DST-ILTP (INT/ILTP/B-2.72) and continue for MOU between Bundelkhand University, Jhansi, India and Institute of Geology, Karelian Research Centre, Petrozavodsk, RAS, Russia.