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[Display omitted] • Juvenile crust in Singhbhum Craton formed at ∼3.51, ∼3.45, 3.38–3.25, 3.15–3.05 and ∼2.80–2.75 Ga. • Reworking of older crust in the craton occurred at ∼3.46, ∼3.3, ∼3.1 and ∼2.8 Ga. • Maximum crustal thickness was attained at ∼3.3 Ga followed by a possible reduction over ∼3.1–2.8 Ga. • Paleo-Meso–Archean continental growth occurred through episodic intraplate juvenile magmatism and resultant crustal reworking. The composition of continental crust and its temporal variation, the mechanism of crust-mantle interaction, and the degree of mantle depletion during the early Archean have been widely debated. To address these issues related to the Singhbhum Craton, we present whole-rock sediment geochemistry, detrital zircon U-Pb date, trace element and Hf isotope data from four Archean clastic sedimentary successions. The rocks have high whole-rock K 2 O/Na 2 O, relatively high La and Th compared to Ni and Sc, distinct negative Eu anomaly and flat HREE patterns, and high detrital zircon U/Yb ratios. These features suggest attainment of early crustal stability with the sediments derived from a strongly weathered basement dominated by granitoids formed through shallow intracrustal melting. Detrital zircon U-Pb and Hf isotope data indicate episodic crust formation at ∼3.51, ∼3.46, 3.38–3.25, 3.15–3.05 and ∼2.80–2.75 Ga. Each major crust formation event is marked by addition of depleted mantle-derived juvenile crust and its quick reworking. Besides, episodic tapping of older crust, as indicated by a wide range (both positive and negative) of zircon εHf t values, are evident at ∼ 3.46, ∼3.3, ∼3.1 and ∼2.8 Ga. Pressure-sensitive zircon trace element ratios suggest that the crust attained the maximum thickness at ∼3.3 Ga followed by a possible reduction in thickness over ∼3.1–2.8 Ga. In the absence of strong evidence of subduction, the rock association and their temporal distribution (coeval granitoid and mafic-ultramafic magmatism) suggest that the Paleoarchean-Mesoarchean crustal growth in the Singhbhum Craton was a result of episodic, depleted mantle-derived, intraplate magmatic injection and attendant crustal reworking. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sources of Cenozoic sediments in the Kuqa Depression were changed for four times. • The South Tianshan Range experienced the Cenozoic intra-continental uplift initiated at 50–46 Ma. • The entire Tianshan Range was rapidly uplifted during the Middle Miocene (13–10 Ma). • The Kuqa fold-thrust belts were mainly formed in the Early Pliocene (∼6.5 Ma). Influenced by the far-field effect of the India–Eurasia collision during the Cenozoic, both the Tianshan Range and Kuqa Depression underwent multi-phases of intracontinental tectonic activation. The extremely thick Cenozoic sediments in the Kuqa Depression recorded the basin-mountain coupling process of the South Tianshan and Kuqa Depression. In this study, detailed structural investigations, stratigraphic analysis, and detrital zircon U–Pb dating of the Cenozoic sediments were conducted in the Kuqa Depression to reconstruct the Cenozoic uplift history of the South Tianshan Range. U–Pb ages of detrital zircon from sandstones show four age peaks that correspond to four significant provenance changes in the Kuqa Depression. These four periods of changes occurred at the Cretaceous–Early Cenozoic, Late Eocene–Oligocene, Early Miocene–Middle Miocene, and Early Pliocene–Early Pleistocene. These changes in provenance reflect variations in tectonic activation and paleogeographic settings in the Kuqa Depression–Tianshan Range. Combined with the syn -tectonic growth strata and previously published magnetostratigraphy and low-temperature thermochronology data, we therefore argue that significant Cenozoic deformation and uplift of the Tianshan Range was initiated at the Early Eocene (50–46 Ma), strengthening in the Late Eocene(∼36 Ma), becoming more evident and extending to the entire Tianshan and Basin–Range boundary during the Middle Miocene (13–10 Ma), and culminating and extending to the southern Kuqa Depression since the Early Pliocene (∼6.5 Ma), thus suggesting the continuous convergence of the on-going India–Eurasia collision in the Cenozoic. [ABSTRACT FROM AUTHOR]

Abstract: Mesozoic post-collisional andesites occur in the Gerze area within the Qiangtang Terrane of northern Tibet, China. Geochronological, geochemical, and whole-rock Sr–Nd isotopic analyses were performed on this suite of volcanic rocks to characterize their petrogenesis. Laser ablation-inductively coupled plasma-mass spectrometry U–Pb zircon analyses yielded consistent ages ranging from 122.4±0.4Ma to 124.4±0.4Ma for two andesite samples (JC01 and GZ01). The andesites belong to the alkaline and sub-alkaline magma series in terms of K2O+Na2O contents (4.7–10wt.%), and belong to the high-K calc-alkaline and calc-alkaline series on the basis of their high K2O contents (1.0–3.3 wt.%). The volcanic rocks are further characterized by the enrichment of light rare earth elements [(La/Yb)N =7.4–11.5] and large-ion lithophile elements (e.g., Rb), slightly negative Eu anomalies (Eu/Eu* =0.79–0.94), and negative anomalies in high field strength elements (e.g., Nb, Ta, and Ti) relative to primitive mantle. The samples show slightly elevated (87Sr/86Sr)i values that range from 0.7049 to 0.7057, and low ε Nd(t) values of −3.4 to 0.7. These results suggest that the rocks were derived from a compositionally heterogeneous mantle source and that their parent magmas are basalt magma. The parent mafic magmas may have undergone fractional crystallization of olivine, pyroxene, hornblende, and to a lesser extent, plagioclase during ascent through the thickened crustal pile, with minor or no crustal contamination, before the finally erupting as andesites. [Copyright &y& Elsevier]