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Palaeo‐Mesoarchean Banded Iron formations (BIFs) of central Bundelkhand greenstone belts occur from Babina (in the west) to Mahoba (in the east) via Mauranipur along with the E–W trending of the Bundelkhand Tectonic Zone (BTZ). In the present study, we report petrological, geochemical, and mineralogical data of BIFs from the Babina, Mauranipur, and Mahoba greenstone belts of central Bundelkhand Greenstone Complex to address their source characteristics and deposition environment. The lithological association of BIFs in the Babina and Mauranipur greenstone belts consists of pillowed basic–ultrabasic volcanics and metasediments, whereas in the Mahoba greenstone belt, BIFs and quartzite occur within basic volcanics. These lithological associations collectively suggest that the entire succession was deposited in a marine environment. Based on geological setting, they are classified as Algoma‐type. The main mineral assemblages of the Babina and Mauranipur BIFs are composed of magnetite, quartz, ±garnet, hornblende, chlorite, and apatite, whereas the Mahoba BIFs along with magnetite and quartz, poised of two distinct mineral assemblages; the first one is Opx–Cpx–Grt and the other one is Grt–Hbl. The preliminary P–T study of these BIFs implies that they had gone through amphibolite‐ to granulite‐facies metamorphism. The geochemical characteristics show that BIFs from the Babina and Mauranipur greenstone belts are dominated by higher quartz and magnetite (total content = 90.63–99.95 wt.%), whereas the Mahoba greenstone belt is characterized by lesser quartz and magnetite components (total content = 86.68–94.58 wt.%). The PAAS (Post Archean Average of Australian Sediments)‐normalized REE patterns display significant positive Eu anomaly (Eu/Eu* up to 2.50) with well‐represented negative Ce anomalies (Ce/Ce* = 0.27–1.20). The REE and trace element ratios of BIFs from the Babina and Mauranipur greenstone belts suggest that they were formed by high‐T hydrothermal fluid activity without or very less continental input. Moreover, the Mahoba greenstone belt BIFs are formed by low‐T hydrothermal fluid activity with substantial continental input. Their chemical variation suggests the shallowing of the proto‐basin from the Babina in the west to Mahoba in the east. Tectonic discrimination plots imply the BIFs of the Babina, Mauranipur, and Mahoba greenstone belts of the central Bundelkhand Greenstone Complex are formed in a back‐arc tectonic setting. [ABSTRACT FROM AUTHOR]

The central Bundelkhand greenstone complex in Bundelkhand craton, northern India is one of the well exposed Archaean supracrustal amphibolite, banded iron formation (BIF) and felsic volcanic rocks (FV) and associated with grey and pink porphyritic granite, tonalite–trondhjemite–granodiorite (TTG). Here we present high precision zircon U–Pb geochronological data for the pinkish porphyritic granites and TTG. The zircons from the grey-pinkish porphyritic granite show three different concordia ages of 2531 ± 21 Ma, 2516 ± 38 Ma, and 2514 ± 13 Ma, which are interpreted as the best estimate of the magmatic crystallization age for the studied granites. We also report the concordia age of 2669 ± 7.4 Ma for a trondhjemite gneiss sample, which is so far the youngest U–Pb geochronological data for a TTG rock suite in the Bundelkhand craton. This TTG formation at 2669 Ma is also more similar to Precambrian basement TTG gneisses of the Aravalli Craton of north western India and suggests that crust formation in the Bundelkhand Craton occurred in a similar time-frame to that recorded from the Aravalli craton of the North-western India. [ABSTRACT FROM AUTHOR]

• First report of two discrete episodes of Neoarchean TTG magmatism in the BC. • 3.34 Ga TTG pluton in the eastern part of the BC. • Six major periods of felsic magmatism during 3.55–2.50 Ga. • Sanukitoid and anatectic granite show peak continental growth during ~2.58–2.50 Ga. • Geochemistry, Hf and Nd isotopes suggest Eoarchean to Neoarchean crustal reworking. In this contribution we present field relations, U-Pb zircon geochronology, in-situ Lu-Hf isotopes, bulk-rock Sm-Nd isotopes and geochemistry of the tonalite-trondhjemite-granodiorite (TTG) gneiss, sanukitoid and anatectic granites from the Central Bundelkhand granite-greenstone terrane (CBGGT). The present study provides a comprehensive insight into the crust-mantle evolution, reworking, and cratonization of the Bundelkhand Craton (BC) during the Archean Eon. We report two discrete episodes of Neoarchean TTG magmatism at ~ 2.71 and ~ 2.68 Ga from the BC for the first time. Additionally, we identify a TTG gneiss that is significantly older (~3.34 Ga) than thus far assumed in the eastern part of the area. Furthermore, zircon U-Pb ages of the sanukitoids and the anatectic granites suggest synchronous emplacement at 2.58–2.50 Ga. Zircon of Paleoarchean TTG, Neoarchean TTG, sanukitoid, and anatectic granites show εHf (t) values in the following ranges: +1.7 to −0.9, +4.1 to −10.7, −3.6 to −6.2, and −5.9 to −7.8, respectively, which are indicative of significant crustal reworking. Neoarchean TTG gneiss shows εNd (t) and εHf (t) value of + 4.5 and + 10.0 to −6.8, respectively, indicating a juvenile crustal source and probably formed by the partial melting of deep-seated mafic crust in the garnet stability field. Neoarchean TTGs formed in arc creation/collision to the Paleoarchean nucleus of the BC. The amalgamation of diverse micro-blocks occurred by the arc-continent collision and probable breakoff of the descending slab between crustal blocks of the BC during Neoarchean. This event generated anatectic granites by intense partial melting of the existing crust, which resulted as closing of subduction and marked as final stabilization and cratonization of the BC. This event also shows evidence that the BC did not amalgamate until ~2.50 Ga. [ABSTRACT FROM AUTHOR]