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As an ordinary alteration mineral in the process of fluid–rock interaction, chlorite (most especially its chemical composition) has the potential to become an effective tool to reveal the physicochemical conditions during alteration and help exploration. However, its elemental characteristics during the chloritization process are yet to be clearly understood. The Dehua‐Youxi‐Yongtai (DYY) ore district in south‐east China is one of the potential areas of gold and polymetallic deposits. Lying in the north‐west section of the DYY ore district, the Donghua area is notable for its remarkable metallogenic potential, and porphyry‐epithermal systems might have developed in the area. This study focuses on the elemental characteristics of chlorite in the Donghua area as footprints of the alteration process and mineralization vectoring. According to the geological features and occurrences, the chlorite from Donghua can be divided into two generations: (a) Chlorite I is closely related to chloritization developed in intrusive and volcanic rocks (Permian quartz monzobiorite and Jurassic volcanic rocks of Changlin Formation), and (b) chlorite II is accompanied by superimposed hydrothermal overprinting. The alteration process suggested by overprinting chlorite II can be regarded as almost coeval with the ca. 154–153 Ma magmatic event, and chlorite II is later than chlorite I generation. According to the geothermometry of the chlorite in Donghua, chlorite I might have crystallized on the temperature of 180–240°C with a peak of ~200°C, and the overprinting chlorite II might have experienced two episodes of hydrothermal/epithermal fluid pulsing. The mineral geochemistry of the trace elements in the two generations of the chlorite in Donghua shows different characteristics. The replacement of Mg2+ by Fe2+ plays an important role for ionic substitution in the octahedral position, especially for chlorite II. The other occasion might be Mg and Fe jointly entering the octahedral position as well as Mg‐ and Fe‐AlVI substitution mechanisms. The enrichment of Mg especially in chlorite II suggests low‐grade oxidation and acid conditions, which might be beneficial for the transportation of metallogenic substances. The obvious differences of Co and Ni are remarkable aspects of the trace elements of chlorite in Donghua, resulted by the ion substitution and function of different octahedral site preference energy. The mineral chemistry of chlorite II from Donghua can be helpful for targeting and exploration vectoring in the DYY ore district. [ABSTRACT FROM AUTHOR]

• The ca. 154 ~ 154 Ma magmatic/hydrothermal episode is recognized. • The granitoids in Donghua exhibit characteristics of both A-type and I-type. • Favorable environment for mineralization in Donghua is distinguished. Located in the southern section of the Wuyi Mountain metallogenic belt, the Dehua-Youxi-Yongtai (DYY) ore district is one of the potential areas of gold deposits in the Fujian province, Southeast China. Gold mineralization is widely distributed in this district, including Qiucun, Shuangqishan, Ancun, and Dongyang gold deposits. However, the DYY ore district is still at a low degree of exploration and research. This paper focuses on the Donghua area in the northwest of the DYY ore district as its typical and integrated volcano-magma mechanism revealed in this study. Combined approaches including zircon SHRIMP U-Pb geochronology, Rb-Sr isochron dating and mineral chemistry of pyrite, and hyperspectral remote sensing are employed, aiming to identify the magmatism, alteration, geological setting, and metallogenic potential of the Donghua area. The zircon SHRIMP U-Pb ages of the granite porphyritic dykes in Donghua are 154.6 ± 1.1 Ma and 153.2 ± 1.2 Ma, respectively, indicating that the dykes were formed in the late Jurassic. The Rb-Sr geochronological age of hydrothermal/epithermal pyrite in Donghua is 153.7 ± 2.4 Ma, which is almost coeval with that of the granite porphyritic dykes within error, and consistent with the regional volcanic-magmatic activity and the metallogenic age of the regional metallogenic event. The granitic dykes in Donghua exhibit the characteristics of both A-type and I-type granitoids, thus indicating the presence of transitional geochemical characteristics. As a result of the subduction of the Pacific Plate towards the Eurasia, the ca. 154–153 Ma magmatic event in the Donghua area occurred at the beginning of large-scale delamination of the continental crust. The zoning distribution of the mineral alteration of chlorite, dickite, kaolinite, and gypsum, the interpretation of volcanic activity from the annular structure of hyperspectral remote sensing, and the inferred deep-seated intrusion emplacing from northwest to southeast are in agreement, thus displaying the volcano-magma-alteration mechanism developed in the Donghua area. The magmatism, dykes, faults, and Neoproterozoic metamorphic rock provide favorable advantages for the mineralization in Donghua, suggesting metallogenic potential. [ABSTRACT FROM AUTHOR]

The population history of Southeast (SE) China remains poorly understood due to the sparse sampling of present‐day populations and limited modeling with ancient genomic data. We report genome‐wide genotyping data from 207 present‐day Han Chinese and Hmong‐Mien (HM)‐speaking She people from Fujian and Taiwan Island, SE China. We coanalyzed 66 Early Neolithic to Iron Age ancient Fujian and Taiwan Island individuals obtained from previously published works to explore the genetic continuity and admixture based on patterns of genetic variations of the high‐resolution time transect. We found the genetic differentiation between northern and southern East Asians was defined by a north–south East Asian genetic cline and our studied southern East Asians were clustered in the southern end of this cline. The southeastern coastal modern East Asians are genetically similar to other southern indigenous groups as well as geographically close to Neolithic‐to‐Iron Age populations, but they also shared excess alleles with post‐Neolithic Yellow River ancients, which suggested a southward gene flow on the modern southern coastal gene pool. In addition, we identified one new HM genetic cline in East Asia with the coastal Fujian HM‐speaking She localizing at the intersection between HM and Han clines. She people show stronger genetic affinity with southern East Asian indigenous populations, with the main ancestry deriving from groups related to southeastern ancient indigenous rice farmers. The southeastern Han Chinese could be modeled with the primary ancestry deriving from the group related to the Yellow River Basin millet farmers and the remaining from groups related to rice farmers, which was consistent with the northern China origin of modern southeastern Han Chinese and in line with the historically and archaeologically attested southward migrations of Han people and their ancestors. Our estimated north–south admixture time ranges based on the decay of the linkage disequilibrium spanned from the Bronze Age to historic periods, suggesting the recent large‐scale population migrations and subsequent admixture participated in the formation of modern Han in SE Asia. [ABSTRACT FROM AUTHOR]

The genus Dyneogamasus is transferred to the subfamily Pergamasinae, and the generic diagnosis is revised. A new mite species, Dyneogamasus serratus Yao & Jin sp. nov., is described and illustrated based on females from Fujian province, China. A key to the known species of the genus is given. [ABSTRACT FROM AUTHOR]