Paleomagnetic study of 1765 Ma dyke swarm from the Singhbhum Craton: Implications to the paleogeography of India

Abstract

We report the first key paleopole as a result of paleomagnetic study on a precisely dated 1765.3±1.0Ma WNW-ESE trending dyke swarm from Singhbhum Craton. This pole has been used in this study to propose the paleogeographic reconstruction of India with Baltica Craton and North China Craton. Incremental alternating field (AF) and thermal demagnetization, isolated high coercivity components with north to north-westerly declination and shallow negative inclination from 9 sampling sites which are representing different individual dykes. The primary origin of the ChRM is supported by the positive baked contact test. The WNW-ESE trending dykes yield a mean paleomagnetic direction with a declination=329.2° and an inclination=−22.8° (k=31.6; α95=9.3°). The positive bake contact test proves the primary nature of remanence. The pole position of Singhbhum Craton at 1765Ma is 45°N, 311°E (dp=5.2 and dm=9.9). Paleogeographic reconstruction at ca. 1770Ma, supported by geological, tectonic and metallogenic evidences indicate that the Baltica Craton and India linkage can be stable for at least ∼370Ma (∼1770–1400Ma). There is also reasonable evidence in support of India-North China Craton spatial proximity at ∼1770Ma.