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Late Mesozoic granites are present throughout the Jiaodong Peninsula in eastern China, but the petrogenesis of these granites, the magma sources, and the geodynamic setting of the magmatism remain unclear. This paper presents new zircon U–Pb geochronological and Lu–Hf isotopic and whole‐rock geochemical data for the Late Jurassic Queshan pluton in the Shandong Peninsula, an area that represents the boundary between the Jiaobei and Sulu ultrahigh‐pressure (UHP) terranes. Laser ablation–inductively coupled plasma–mass spectrometry zircon U–Pb dating yields Late Jurassic ages from 158 ± 1 to 153 ± 1 Ma for the pluton in addition to a small number of inherited zircons that yield ages that cluster at 2410, 1831–1776, 750, and 209–202 Ma. Zircons from different samples have similar 176Hf/177Hf values (0.281926–0.282255) and variably negative εHf (t) values that range from −26.5 to −15.1 (weighted mean of −22.9 ± 0.9). The corresponding two‐stage Hf model ages range from 2,869 to 2,154 Ma, with a weighted mean value of 2,645 ± 54 Ma. These data indicate that the magmas that formed the Queshan pluton were derived from multiple sources, including the lower crust of the North China (NCC) and Yangtze (YC) cratons, as well as collision‐related alkaline rocks. The whole‐rock geochemical compositions of the samples indicate that the granites are weakly peraluminous, are high‐K and calc‐alkaline with I‐type affinities, and have high contents of Sr, low contents of Y and Yb, high (La/Yb)N and Sr/Y values, and positive Eu anomalies (δEu = 1.20–1.65), indicating an adakitic affinity. This indicates that the Queshan granites formed from magmas generated by partial melting of a thickened region of the crust (>50 km) associated with eclogite, garnet amphibolite, or amphibolite residual material. The genesis of the Late Jurassic granites are also likely to have been influenced by the collisional orogeny between the NCC and YC and continued subduction of the Izanagi Plate. Thickening of the lower crust associated with this continental collisional event occurred before the magmatism, with further compression and thickening of the lower crust caused by the low‐angle subduction of the Izanagi Plate beneath northeastern China being the main geodynamic driver of the formation of the granites in this region. [ABSTRACT FROM AUTHOR]

The Liaoshang gold deposit in the Jiaodong area of the Shandong Province is best known for its super‐large size. Situated on the north‐eastern margin of the Jiaolai Basin, it forms a part of the Jiaobei terrane of the North China Block. Approximately 20 ore bodies within the Liaoshang gold deposit have been explored; of these, four are structurally controlled gold‐bearing pyrite–dolomite vein‐type deposits. These ore bodies lie in an NE‐trending altered fracture zone and are characterized by their thickness and high‐grade ores. The wall rocks of the ore bodies consist of Paleoproterozoic Jingshan Group metamorphic rocks and Mesozoic granites. Gold is hosted mainly in pyrite and dolomite. The ore is divided into two subtypes—the dominant pyrite–dolomite vein subtype and the subordinate altered rock subtype which contains pyrite and dolomite. Fluid inclusions within dolomite indicate that the main metallogenic period was dominated by a CO2–NaCl–H2O fluid system that had low‐moderate salinity, low density, high abundance of CO2, and a small amount of N2. The ore formed at 81‐ to 94‐MPa pressure and between 2.97‐ and 3.24‐km depth. Research on the S, Pb, C, O, and He–Ar isotopes in the gold‐bearing minerals suggests that the ore‐forming material was mainly crustal in origin, with some degree of crust–mantle mixing. The application of Rb–Sr isotope analysis to gold‐bearing pyrite yields a metallogenic age of 105.5 ± 9 Ma. The Sm–Nd isotope analysis of dolomite yields an age of 104.8 ± 5.1 Ma. We propose that gold mineralization in the Jiaodong area occurred in two phases: the early Early Cretaceous for gold deposits in the north‐west and the late Early Cretaceous for gold deposits in the east. [ABSTRACT FROM AUTHOR]

Eastern Shandong is one of the most economically important regions for ore‐producing sedimentary‐metamorphic graphite deposits in China. The Liugezhuang and Daliangzikou graphite deposits in the Pingdu–Laixi Graphite Belt are typical examples. The ores in the Liugezhuang deposit and Daliangzikou deposit are typically gneiss/granulite type and biotite granulite type, respectively. Graphite occurs as stratabound layers of slender flakes associated with biotite, clinopyroxene, and plagioclase and as slender flakes and disseminated grains associated with biotite and filling tiny fractures in mineral grains. The mineral associations indicate that the ore rocks can be classified into four metamorphic facies: (a) amphibolite granulite facies, Cpx (Hy) + Opx (Di) + Pl ± Hbl ± Qz; (b) amphibolite facies, Hbl + Pl + Cpx (Opm) + Ep + Bt + Ms + Qz ± Chl ± Mic; (c) high‐grade greenshist facies, Hbl + Pl + Ep + Bt + Chl + Qz ± Cpx; and (d) low‐grade greenshist facies, Ep + Chl + Pl + Bt + Ms + Chl + Qz + Rt. Study of the variation in graphite crystals and fixed carbon with increasing metamorphic grade suggests that more than one metamorphism process (graphitization) occurred during ore formation. Geochemical analysis indicates that the primary condition under which the Liugezhuang and Daliangzikou graphite deposits formed was a marine facies sedimentary environment of which the material source was terrestrial weathering detritus and compounds and also a participation of terrestrial material in the graphite deposits. Trace element data suggest that the sedimentary condition was from a reducing condition in the Liugezhuang graphite deposit to a weaker reducing condition in the Daliangzikou graphite deposit, whereas samples from a Jingshan Group stratum show multiple oxidation–reduction conditions but dominantly oxidation. Carbon isotope analysis indicates that the carbon source of the Liugezhuang graphite deposit was organic, whereas that of the Daliangzikou graphite deposit was mainly organic carbon but with some inorganic participation. [ABSTRACT FROM AUTHOR]