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(a) Geological map of the Liaodong area (modified from Wu et al., 2005). GDL-Gudaoling monzogranite; YMWS-Yinmawanshan granodiorite; XMS-Xiemashan granite; FHS-Fenghuangshan granite; SDG-Shuangdinggou monzogranite; DQS-Dingqishan syenogranite; WLB-Wulongbei granite. (b) Geological map of the Jiaodong area (modified from Fan et al., 2003). ZY-LZ MB-Zhaoyuan-Laizhou metallogenic belt; PL-QX MB-Penglai-Qixia metallogenic belt; MP-RS MB-Muping-Rushan metallogenic belt; LL-Linglong monzogranite; GJL-Guojialing granodiorite; LJH-Luanjiahe granite; AS-Aishan granite; KYS-Kunyushan granite; SFS-Sanfoshan granite; WDS-Weideshan granite.
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Post-mineralization thermal evolution is an indispensable part for geology of ore deposits. However, as two important gold mineralization regions in eastern China, the thermal histories after ore formation of the Jiaodong area is debated while that of the Liaodong area is scarce. Given that the two areas are not only in similar tectonic settings bu...
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... which is located to the west of the Yalujiang fault (Fig. 1b) has undergone frequent magmatic activity since the Mesozoic and contains abundant mineral resources. Sedimentary strata in the Liaodong area are dominated by the Liaohe Group, which is a set of extremely thick clastic and carbonate rocks that formed during Paleoproterozoic rifting (Fig. 2a). Late regional thermodynamic metamorphism and deformation at ca. 1.85-1.9 Ga affected this rock series ( Sun et al., 1993;Chen et al., 2005;Wan et al., 2006;Luo et al., 2004Luo et al., , 2008. The Liaohe Group strata comprise the Langzishan, Lieryu, Gaojiayu, Dashiqiao, and Gaixian formations, in ascending stratigraphic order (Chen, ...
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... deposits in the Liaodong area are distributed in the Liaodong rift and include the Baiyun, Maoling, Wulong, Sidaogou, Xiaotongjiabaozi, Taoyuan, Yangshu, and Linjia gold deposits (Fig. 2a). The controls on the occurrence of gold deposits in the Liaodong area include the following: (1) Stratigraphy. Gold ores occur mainly in the upper part of the third member of the Dashiqiao Formation and the lower clastic rock unit of the Gaixian Formation ( Liu et al., 2013). (2) Lithology. Gold ores occur most commonly in dolomite ...
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... Jiaodong area is located on the eastern margin of the North China Craton and is bordered by the Tanlu fault zone to the west. The area consists of three structural units: the Jiaobei anticline, the Jiaolai basin, and the Sulu orogenic belt (Fig. ...
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... rocks in Jiaodong are extensively developed in the north and northeast of the area. These rocks can be divided into three periods of formation, namely, Late Triassic, Late Jurassic, and Early Cretaceous (Fig. 2b). Upper Jurassic rocks (U-Pb age of 160-149 Ma; Yang et al., 2012a,b) are the most widely exposed rocks in the Jiaodong area and include the Linglong, Luanjiahe, Kunyushan, Wendeng, Duogushan, and Queshan rock masses. The main lithologies are monzodiorite, granodiorite, and quartz diorite. The Lower Cretaceous granites can be further ...
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... 200 gold deposits have been discovered in the Jiaodong area, the largest gold producing province in China (Au reserves of > 3000 tons), and can be divided into three metallogenic belts from west to east (i.e., the Zhaoyuan-Laizhou, Penglai-Qixia, and Muping-Rushan metallogenic belts; Fig. 2b), of which the Zhaoyuan-Laizhou metallogenic belt contains the large-superlarge gold deposits of the area, including the Sanshandao, Jiaojia, and Xincheng gold mines ( Zhou et al., 2002;Fan et al., 2003;Goldfarb and Santosh, 2014). The main types of gold deposit in Jiaodong are altered-rock types controlled by major faults and ...
Citations
... Previous thermochronological studies also revealed Early Cretaceous rapid cooling and exhumation related to metamorphic core complex evolution (e.g., Liang et al., 2022;Lin et al., 2013b;Yang et al., 2007;Zhu et al., 2015) and gold mineralization in the Shandong Peninsula (e.g., Yang et al., 2016;Zhang et al., 2019Zhang et al., , 2020b and Yanshan fold belt (Fu et al., 2020). However, numerous studies in the Shandong and Liaodong Peninsulas and Bohai Bay Basin of the eastern North China craton have placed greater emphasis on the pulsed Late Cretaceous to Paleogene exhumation processes (e.g., Cheng et al., 2015;Jia et al., 2021b;Wang et al., 2022b;Wu et al., 2016Wu et al., , 2018Yang et al., 2020). Both carbonate clumped-isotope paleothermometry from the easternmost Yanshan fold belt and paleoelevation reconstructions based on whole-rock trace element analyses (Zou et al., 2021) suggest paleoelevations of >3 km during the late Early Cretaceous. ...
... The younger, middle Cretaceous event that is constrained by very low lag-time values in sample Y12 (Fig. 10B) is also documented in nearby regions. Rapid cooling and exhumation are also revealed by other thermochronological data from the Liaodong Peninsula (Figs. 11J and 11K;Wang et al., 2022b), the Jiaodong Peninsula (Figs. 11M, 11P, and 11Q;Sun et al., 2022a), the Sui-Jia region ( Fig. 11O; Li, 2019), the Taihangshan ( Fig. 11N; Wu et al., 2020), and the Yanshan fold belt ( Fig. 11L; Chen, 2019), and the evidence is consistent with: (1) a major provenance change documented in the Songliao Basin , (2) the initiation of thermal subsidence and depocenter migration toward the northwest (Zhang et al., 2017), and (3) the occurrence of high-elevation coastal mountains along the eastern Asian margin . A similar tectonic exhumation and topographic change event happened in a compressional setting as documented by short-lived middle-Cretaceous shortening deformation in the Jiaolai Basin (Zhang et al., 2020a) and Erlian Basin (Guo et al., 2018) in the northern North China craton, probably arising from the collision between the Okhotomorsk block and eastern Asia continent at about middle Cretaceous time (Yang, 2013). ...
The late Mesozoic tectonic evolution of the eastern North China craton was intimately related with the subduction of the paleo-Pacific plate. This study sheds light on Late Jurassic−Early Cretaceous basin-mountain coupling during paleo-Pacific subduction based on low-temperature thermochronology and geochemical analyses from the easternmost Yanshan fold belt, located at the northern edge of the craton. We performed apatite U-Pb and fission-track double dating and trace element analyses of basement and sedimentary rock samples, integrated with zircon and apatite (U-Th)/He analyses on bedrock samples. Our results revealed that the easternmost Yanshan fold belt experienced two stages of rapid cooling and exhumation in the Middle Jurassic−earliest Cretaceous (ca. 170−140 Ma) and in the Early Cretaceous (ca. 140−90 Ma). The Middle Jurassic−earliest Cretaceous exhumation (ca. 170−140 Ma) is mainly recorded by bedrock along the margins of intermontane basins of the eastern Yanshan fold belt. This exhumation event is consistent with compressional Yanshan movement during the Middle Jurassic−earliest Cretaceous coeval with paleo-Pacific flat-slab subduction. Subsequent Early Cretaceous rapid cooling is ascribed to the progressive evolution of the metamorphic core complexes and associated tectonic exhumation of major plutons of northeastern Asia, which were likely controlled by rollback of the paleo-Pacific slab. A middle Cretaceous (ca. 110−90 Ma) tectonic exhumation event is revealed by very low lag-time values in middle Cretaceous strata. Our findings illustrate the potential of a thermochronology approach that combines single-grain double dating and trace element analyses in synmagmatic orogenic systems, which may find application to other orogenic settings worldwide.
... This is in accordance with the MCC cooling processes in the North American Cordillera and the Mediterranean Aegean/Anatolia region [71]. Correspondingly, a rapid uplift occurred in the LP since 110 Ma [72]. This may have resulted from a rapid decrease in temperature caused by the exposure of the middle and lower crusts to the shallow surface and heat transfer to the surrounding rock. ...
Metamorphic core complexes are developed in crustal activity belts at the continental margins or within continents, and their main tectonic feature is that the ductile middle crust is exhumed at the surface. The deformation properties are closely related to the geodynamic process affecting the continental crust. However, the evolution of the metamorphic core complexes after their formation is still unclear. The Cretaceous Liaonan metamorphic core complex developed in the eastern North China craton provides an ideal environment to study its evolution. In this study, we estimate the paleo-temperature and paleo-stress at the time of formation of the metamorphic core complex dynamical recrystallization of quartz and calculate the thermo-rheological structure of the present Liaonan metamorphic core complex by one-dimensional steady-state heat conduction equation and power-creep law. The results show that compared with the Cretaceous period, the geothermal heat flow value of the present Liaonan metamorphic core complex decreases from 70–80 mW/m2 to 49.4 mW/m2, the thermal lithosphere thickness increases from 59–75 km to 173 km, and the brittle transition depth increases from 10–13 km to about 70 km, showing coupling of the crust–mantle rheological structure. We speculate that the evolution of the thermo-rheological structure of the Liaonan metamorphic core complex is possibly caused by rapid heat loss or lithospheric mantle flow in the Bohai Bay Basin.
Molybdenum (Mo) is an important globally strategic metal and mostly occurs as molybdenite (MoS2) in diverse Mo deposits. The Yuku ore field includes multiple porphyry-skarn Mo deposits and forms an significant world-class Mo cluster in the Qinling molybdenum belt, central China. Previous studies on the ore field were largely related to its genesis, and did not highlight the post-mineralization modifications that are important to formulate prospecting strategies. The exhumation and preservation processes of the ore field through multiple tectonic events also remain poorly understood. Here, we conducted multi-method apatite U-Pb, fission-track and (U-Th)/He and zircon (U-Th)/He medium- to low-temperature thermochronology and associated thermal history modelling on granitoids from the ore-hosting Shibaogou and Yuku plutons in the Yuku ore field, and integrated published studies to unravel the post-mineralization exhumation and preservation of Mo deposits. The newly determined apatite U-Pb (158.3–104.9 Ma), zircon (U-Th)/He (158.2–121.2 Ma), apatite fission-track (90.8–63.1 Ma), and apatite (U-Th)/He (67.8–35.3 Ma) ages in this study document multiple cooling pulses during post-magma emplacement. The low-temperature thermochronological ages of 158.2–35.3 Ma also recorded the post-mineralization cooling and exhumation history. The thermal history modelling indicates an Early Cretaceous (132–125 Ma) rapid cooling pulse, two enhanced (or accelerated) cooling pulses at ca. 125–59 Ma and post-10 Ma, together with a slow cooling or reheating pulse at ca. 59–10 Ma in the Yuku ore field. The Early Cretaceous rapid cooling is related to the coeval collisional tectonics of the East Qinling Orogen. The enhanced cooling at ca. 125–59 Ma is triggered by the post-collisional assembly of the North China and Yangtze Blocks, the subduction of Paleo-Pacific Plate, and the sinistral strike-slip motion of the nearby Tan-Lu Fault Zone. The slow cooling during ca. 59–10 Ma and the post-10 Ma enhanced cooling are correlated with the extensional tectonics derived by the subduction of Pacific Plate and the far-field effects from India-Eurasia collision. In the Yuku ore field, the Yuku area underwent lower exhumation in comparison to the nearby Shibaoguo and Huangbeiling areas, which thus is helpful to the preservation of Mo deposits. The un-exhumated areas within 1.0 km at the inner and outer contact zones between the Yuku pluton and its wall rocks are postulated to be favorable sites for Mo prospecting. In addition, the un-exhumated areas surrounding other Late Mesozoic plutons in the Luanchuan region are also suggested to have high potential for Mo exploration.
Plain Language Summary
Thermochronological data sets enable orogen‐scale investigations into the spatio‐temporal patterns of exhumation on continental margins, and provide additional constraints on how the tectonic evolution of the crust is controlled by subduction. We employ geochronology (zircon U‐Pb), low‐temperature thermochronology (zircon, apatite (U‐Th)/He) and medium‐high temperature thermochronology (titanite, apatite U‐Pb) data to model the thermal evolution histories of the southernmost segment of the GXR in NE China. The inverse modeling results show rapid cooling and exhumation from ca. 155–110 Ma. This coincides with the initiation of slab roll‐back of the Paleo‐Pacific Ocean in NE Asia, which was responsible for cooling and exhumation in an extensional regime. In addition, we compile the available low‐temperature thermochronology data (zircon, apatite fission track and (U‐Th)/He) from the NE Asian continental margin from Late Cretaceous (ca. 110 Ma) to constrain regional exhumation events. These data show three main exhumation phases from the Late Cretaceous onwards. Combined with the data on the regional evolution of magmatism, sedimentary basins and deformation, the three exhumation phases can be linked to changes in the geometry of the Paleo‐Pacific ocean and Pacific ocean plates in NE Asia, thus showing coupling between continental exhumation and subduction.
