Isotopic Sm-Nd signatures of Precambrian Banded Iron Formation from the Fennoscandian shield, East-European Platform, and Bundelkhand craton, India

Abstract

In this communication, we report geochemical and Sm-Nd isotope data of Banded Iron Formation (BIF) from Kola-Karelia (Fennoscandian shield), East-European Platform and Bundelkhand craton, N-E India. The BIFs from Kola-Karelia (Algoma type), and Bundelkhand Craton (Algoma type), north-central India, and East-European Platform (Superior type) characterized by alternate domains of quartz-rich and iron-rich layers. Except for magnetite and hematite, orthopyroxene, amphibole, and garnet are the other dominant minerals present the BIF’s. The shale-normalized REE spectra of iron-rich layers of Bundelkhand, Kola-Karelia and East European BIFs are similar. The εNd[t] for silica-rich layers is higher compared to the iron-rich layers for all studied samples. The higher εNd[t] values (around +5.0) for silica-rich layers from Kola-Karelia, Bundelkhand BIF and East European Platform suggest a juvenile source for silica. The lower εNd[t] values (−5 to +2) for iron-rich layers from the same samples implies continental source for the iron. The present study suggests that the sedimentation mechanisms of silica and iron for Algoma as well as Superior types BIFs are similar despite spatial diversity.