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Abstract Five successive deformation phases have been identified from structural analysis of granitoid and gneissic rocks of the study area. The magnetic foliation data of the studied granitoids show two distinct NW and NE trending sets. The NW trending magnetic foliation is found to be essentially parallel to the mesoscale planar structures of regional D1-D2 deformations and is thus correlated with the D1-D2 phases. On the contrary, the NE trending magnetic foliation appears to be kinematically compatible with the NW-SE compression direction deciphered from conjugate ductile shear zone patterns of the D3 event. Combining AMS, field and microstructural data, the granitoid outcrop have been separated into older D1-D2 and younger D3 domains. The published geochronological data from the area when compared with the established D1-D2 and D3 domains, shows a good correlation pointing tentatively the timing of the D1-D2 deformation phase to be ∼2550 Ma while the D3 phase to be ∼2524 Ma. Hence the study highlights the importance of combining AMS data with field and microstructural studies to constraint the timing of regional successive deformation imprints. It also helps to identify the chronologically separated emplacement phases of the granitoid massif in question, which would not have been possible otherwise. Highlights • The deformed Neoarchaean granitoids of the study area in the EDC, south India show evidences of five successive deformation imprints (D1-D5). • The D1-D3 phases represent early ductile episodes which are well documented from the EDC. • The hitherto undetected D4-D5 phases represent essentially brittle shallow crustal events of which the overlying Mesoproterozoic Srisailam Formation manifests the D5 phase only. • The observed magnetic fabrics from granitoids depict NW-SE and NE-SW trends which are correlated with D1-D2 and D3 deformation phases respectively. • AMS data along with field, microstructural and published geochronological data help to constraint the chronology of successive deformation imprints and identify the separate emplacement phases in the granitoid massif. [ABSTRACT FROM AUTHOR]

Geochemical and zircon U–Pb age data on granites of the Chitrial area, situated at the NE part of the Eastern Dharwar Craton, are presented to elucidate their petrogenesis, time(s) of emplacement, and role in crust formation. Based on field and geochemical characters, these granites are classified as alkali feldspar/monzo‐granite. Whole‐rock data of selected samples show evolved calc‐alkaline and peraluminous characters with high SiO2, K2O, large‐ion lithophile element, and light rare earth elements (LREE), depleted heavy rare earth elements (HREE) and strongly negative Eu anomaly. One sample shows slightly different character with low SiO2, enriched light rare earth elements, and depleted heavy rare earth elements without Eu anomaly. Geochemical analyses suggest that the rocks are S‐type granite with syn‐collisional and volcanic arc signatures. These granites define a coherent trend favouring low pressure crystallization of the magma. U–Pb zircon data show that the crystallization ages of the granites vary within 2514 ± 10 to 2525 ± 24 Ma. The geodynamic evolution of the Eastern Dharwar Craton is discussed wherein subduction and deep burial of sediment is envisaged to cause partial melting and granite genesis in the craton. [ABSTRACT FROM AUTHOR]

[Display omitted] • Duration of sedimentation in the Srisailam sub-basin was > 1840 Ma ≤ 1770 Ma. • The Srisailam Formation formed in a passive margin setting. • The dominant source area for the Srisailam Formation was the Dharwar Craton. • The Srisailam Formation contains Palaeo-Mesoarchaean and traces of Haedean zircons. • The Srisailam Formation is correlated with the Pulivendla Formation, Chitravati Group. The Mesoproterozoic Cuddapah Basin consists of four unconformity-bound sequences, i.e., Papaghni Group, Chitravati Group, Srisailam Formation and Kurnool Group. A fair amount of geochronological and geochemical data is available from the basal Papaghni Group and Chitravati Group as well as the overthrusted Nallamalai Group. Due to limited geochronological and geochemical constraints, the Srisailam Formation, however, remains a subject of speculation regarding the time of sediment deposition, sediment source locations, and tectonic setting. In this work, we present new geochronological and geochemical data (zircon U-Pb) from samples of the Srisailam Formation. The new data suggest that the Srisailam Formation correlates temporally with the basal Chitravati Group and is largely disparate from the allochthonous Nallamalai Group. The sediments of the Srisailam Formation contain a minor yet significant number of Palaeo-Mesoarchaean detrital zircon with traces of Haedean zircon. Based on our detrital zircon data, we argue that the sedimentation in the Srisailam sub-basin initiated after ca. 1840 Ma and continued till ≤ ca. 1770 Ma and the sediments were mainly sourced from Neoarchaean to Paleoproterozoic terrains including the Dharwar Craton, and sedimentation was initiated in a rift basin that subsequently evolved to a passive margin setting. [ABSTRACT FROM AUTHOR]