Herein, new zircon U-Pb ages, whole-rock major and trace element geochemistry, and Hf isotopes are presented for four Mesozoic granitic rock samples within the Qingchengzi district, eastern China. These data provide precise age and petrogenesis information with respect to the Mesozoic intrusions in the Qingchengzi district, which further constrain the initial decratonization process of the eastern North China Craton (NCC). The zircon U-Pb data reveal that these granitoids are emplaced in the following two stages: Triassic (243-220 Ma) and Middle Jurassic (∼164 Ma). These Mesozoic rocks (lithology: syenogranite, monzogranite, and biotite granite) contain high concentrations of silica (68.94-77.07 wt.%) and total alkali (7.35-9.71 wt.%) together with low concentrations of MgO (0.07-0.98 wt.%), total Fe 2 O 3 (0.81-2.92 wt.%), and CaO (0.17-1.80 wt.%), and they are characterized by an enrichment of large-ion lithophile elements (LILEs; e.g., Rb, Cs, and K) and light rare earth elements (LREEs)in addition to depletion of high-field-strength elements (HFSEs; e.g., Nb, Ta, and Ti) and heavy rare earth elements (HREEs), indicating that these Mesozoic rocks are similar to I-type granitoids. The ε Hf (t) values of the magmatic zircons in these granitoids range from −18.7 to −11.4. Such geochemical characteristics indicate that these granitoid formations were generated by the partial melting of the ancient lower crustal material. However, the occurrence of mafic microgranular enclaves in the Shuangdinggou monzogranite implies the mixing of the mantle-derived magmas.Combined with the results of the previous research, these new data indicate that initial decratonization of the eastern NCC occurred during the Triassic period in response to the collision and amalgamation of the Yangtze Craton and NCC. During the Jurassic, the dynamic mechanism of lithospheric thinning was overprinted owing to the subduction of the Paleo-Pacific Plate. Furthermore, cratonic destruction reached its peak during the Early Cretaceous, which could be related to the asthenospheric upwelling induced by the rollback of the subducting oceanic slab.[Correction added on 21 October 2019, after first online publication: Funding information has been added.]

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Mineralogical characteristics of coastal sediments and their spectral characteristics related to moisture content were analysed for South Korea in this study, and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) shortwave infrared (SWIR) remote sensing approaches for moisture content mapping based on conventional SAM module were proposed in this study. The mineral composition included the major minerals of quartz, alkali feldspar, plagioclase and calcite and the accessary minerals of mica and clay. The absorption features of coastal sediments studied occurred at wavelengths of 1.900 μm for clay minerals and water, 2.200 μm for clay minerals and 2.350 μm for micas and calcite. The spectral signature changed with increased moisture content as the absorption feature at 2.200 μm and 2.350 μm faded out. The fading absorption features shifted the resampled laboratory spectra in a spectral vector space and enabled the use of a SAM module for the ASTER SWIR data. The SAM method effectively distinguished not only the absolute moisture content distribution using the reference spectra but also the relative moisture content distribution without the actual reference spectra for coastal sediments. Given that mineral composition and absorption feature behaviours with regard to the moisture content of soil samples are similar to coastal sediments, this method may be applicable for soil moisture mapping.

The Shinyemi and Gagok deposits, located in the Taebaeksan Basin, South Korea, display Zn–Pb mineralization along a contact between Cretaceous granitoids and Cambrian–Ordovician carbonates of the Joseon Supergroup. The Shinyemi mine is one of the largest polymetallic skarn‐type magnetite deposits in South Korea and comprises Fe and Fe–Mo–Zn skarns, and Zn–Cu–Pb replacement deposits. Both deposits yield similar Cretaceous mineralization ages, and granitoids associated with the two deposits displaying similar mineral textures and compositions, are highly evolved, and were emplaced at a shallow depth. They are classified as calc‐alkaline, I‐type granites (magnetite series) and were formed in a volcanic arc. Compositional variation is less in the Shinyemi granites and aplites (e.g., SiO2 = 74.4–76.6 wt% and 74.4–75.1 wt%, respectively) than in the Gagok granites and aplites (e.g., SiO2 = 65.6–68.0 wt% and 74.9–76.5 wt%, respectively). Furthermore, SiO2 vs K/Rb and SiO2 vs Rb/Sr diagrams indicate that the Shinyemi granitoids are more evolved than the Gagok granitoids. Shinyemi granitoids had been already differentiated highly in deep depth and then intruded into shallow depth, so both granite and aplite show the highly evolved similar chemical compositions. Whereas, less differentiated Gagok granitoids were separated into two phases in the last stage at shallow depth, so granite and aplite show different compositions. The amounts of granites and aplite are similar in the Shinyemi deposit, whereas the aplite appears in an amount less than the granite in the Gagok deposit. For this reason, the Shinyemi granitoids caused not only Fe enrichment during formation of the dolomite‐hosted magnesian skarn but also was associated with Mo mineralization in the Shinyemi deposit. Zn mineralization of the Gagok deposit was mainly caused by granite rather than aplite. Our data suggest that the variation in mineralization displayed by the two deposits resulted from differences in the compositions of their associated igneous intrusions.