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The Tak Batholith is located in the western part of Thailand’s eastern granitoid belt. To better understand the geochemical characteristics of granitoid and identify their occurrence, rock samples collected from the eastern part of the Tak Batholith were used for petrographical, mineralogical, and geochemical analyses. According to field investigation and lithology, petrography classifies these granitic rocks as medium-grained granodiorite and granodioritic dike. The granodiorites are composed chiefly of plagioclase, orthoclase, quartz, hornblende, and biotite, with tiny amounts of zircon, apatite, and opaque minerals. Meanwhile, the granitic dike shows a highly porphyritic texture, presenting mostly plagioclase phenocrysts, with a small amount of orthoclase and unidentified mafic phenocrysts sitting in a fine-grained groundmass comprising K-feldspar and quartz with a small amount of plagioclase and present granophyric intergrowth. Geochemical data of the amphiboles classified them as Ferro-edenite symbolizing the I-type granite. Whole-rock geochemistry indicates that these rock suites are I-type metaluminous granodiorite, and diorite fractionated from the high K calc-alkaline magma melted from the mafic crust of arc magmatism agreeable with the enrichment of large ion lithophile elements and depletion of highfield-strength elements, and rare earth element patterns.

Early Cretaceous granitic rocks are widely distributed in the Great Xing’an Range, northeast China. However, their precise age and tectonic evolution remain controversial. This study presents new zircon U–Pb, Lu–Hf, and whole-rock geochemical data for the granitic plutons in the Yili area, Xing’an Massif, northern Great Xing’an Range. The aim of this study was to decipher the tectono-thermal history and obtain further understanding of the geodynamic setting of the large-scale Late Mesozoic magmatism in the Great Xing’an Range. Zircon U–Pb age dating indicated that the plutons were emplaced during the Early Cretaceous, with ages of 132.2–130.1 Ma. The plutons showed similar geochemical features, characterized by high concentrations of SiO2 and Na2O + K2O and low concentrations of P2O5, CaO, MgO, and TFe2O3. The plutons were enriched in light rare earth elements and large ion lithophile elements and depleted in heavy earth elements and high-field-strength elements. Such features indicate that the plutons are highly fractionated with I-type granite affinity. These findings, combined with pluton ε Hf(t) values of + 5.25 to + 8.28 and two-stage model ages (t DM2) of 661–855 Ma, indicate that the primary magmas originated from partial melting of juvenile basaltic crustal material accreted during the Neoproterozoic. These results combined with regional geological evolution indicated that the generation of Early Cretaceous plutons in the northern Great Xing’an Range might be closely related to the post-collisional gravitational collapse and subsequent extension resulting from the closure of the Mongolia-Okhotsk Ocean. Their generation also superimposed the back-arc extension resulting from retraction of the Paleo-Pacific subduction plate.

The evolution process of the North China Craton has been discussed by many scholars; however, the frame for the timing of the Trans-North China Block has not been fully agreed upon. Related research has mostly focused on the northern and southern sections of the Trans-North China Block, and in-depth studies on intrusive rocks in the central region are lacking. In this study, we conduct a systematic study of the petrography, the whole-rock geochemistry, and the zircon U–Pb dating for the beschtauite intrusion, located in the Mengjiaping area of the Southern Taihang Mountains. Our results demonstrate that the dyke intrusion is mainly composed of beschtauite. Laser ablation inductively coupled plasma mass spectrometry zircon U–Pb dating shows that the beschtauite intrusion occurred at ∼1,880 ± 69 Ma. The beschtauite belongs to I-type granite, Arc tholeiite series, and Cale-alkaline series, with low total alkali, low potassium, and high aluminum. They are also enriched in large-ion lithophile elements, relatively depleted in high-field strength elements, and low total rare-earth elements. Based on the abovementioned data, it is suggested that the magmas for the beschtauite intrusion were metasomatized by oceanic slab subduction in the Late Paleoproterozoic. The formation time of the North China Craton basement should be set to after 1,880 Ma.