Precambrian crustal evolution in Northern Indian Block: Evidence from detrital zircon U-Pb ages and Hf-isotopes

Abstract

Integrated detrital zircon U–Pb and Lu–Hf isotope analyses were conducted on three siliciclastic sedimentary rock samples from the Vindhyan Supergroup in the Son Valley section of central India. These display two prominent 2.7–2.4 Ga and 1.9–1.5 Ga age groupings along with minor Paleoarchean-Mesoarchean (3.5–2.9 Ga) and late Mesoproterozoic (1.3–1.0 Ga) zircons. These 3.5–1.5 Ga detrital zircons match well with the exposed magmatic and metamorphic rock components within the Bundelkhand and Aravalli cratons of the Northern India Block. Zircon grains of >2.0 Ga mainly produce negative εHf(t) values suggestive of episodic recycling and reworking of old crust components in Northern India Block, whereas zircon grains in the age range of 2.0–1.4 Ga commonly produce positive εHf(t) values, indicating dominant juvenile crust growth in response to assembly and breakup of Columbia supercontinent. Contemporaneous mafic dykes (2.15–2.0 Ga and ca. 1.98 Ga) intruded into the Bundelkhand Igneous Complex present direct lithological evidence for juvenile crustal growth. Similar basement rock compositions and detrital zircon age distributions provide robust evidence that the Bundelkhand craton has possibly been combined with the Aravalli-Banded Gneiss Complex (ABGC) since Paleoproterozoic. 1.3–1.0 Ga old detrital zircons could have sourced from South China or the Central Indian Tectonic Zone or the Eastern Ghats or a pre-existing hidden terrane in India; their dominant negative εHf(t) values suggest reworking of old crustal components in Northern India Block in response to the assembly of Rodinia supercontinent.