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Peng N.,Chinese Academy of Geological Sciences | Liu Y.-Q.,Chinese Academy of Geological Sciences | Kuang H.-W.,Chinese Academy of Geological Sciences | Xu H.,Chinese Academy of Geological Sciences | And 4 more authors.
Geology in China

Using the paleocurrents, gravels composition and detrital zircons age spectrum, the authors analyzed the provenance of Early Cretaceous Laiyang Group in Jiaolai basin and its geological significance. The paleocurrents show a stable northward direction in Wulian-Zhucheng, but gradually change from E-SE at the early stage to W-NW at the late stage in Laiyang-Rushan. Gravels in Wulian- Zhucheng- Jiaozhou comprise mainly granite gneiss, granite, marble and quartzite; in Laiyang- Rushan, however, granites are dominant at the early stage and multiple gravels are present at the late stage. Detrital zircons ages are primarily distributed in the ranges of 110-145 Ma, 150-180 Ma, 200-250 Ma, 600-950 Ma and 1700-2600 Ma, whereas Paleozoic zircons are rarely seen. All these features indicate that there existed three main sources for Early Cretaceous Jiaolai Basin: HP-UHP metamorphic rocks and shallow metamorphic complex of Sulu orogen, Yanshanian granites (J2-3-K1), and Metamorphic rocks from the Jiaobei uplift. Additionally, the regional difference of provenance is apparent, which suggests the southern part and the northern part of Sulu orogenic belt experienced different orogenic processes. The southern Sulu orogenic belt experienced large-scale uplift and was stable, whereas the northern Sulu orogenic belt was subjected to small-scale uplift and collapsed at the late stage. It is also concluded from the provenance that the ancient landform of Jiaolai basin in the southwest was higher than in the east during the sedimentation of Early Cretaceous Laiyang Group until the late stage of the sedimentation when the east part of the basin was uplifted. Source

Zhang G.,Shandong University | Pan Z.,Shandong Institute of Geological science | Wang X.,Shandong Environmental Protection Research Institute | Mo X.,Shandong Environmental Protection Research Institute | Li X.,Shandong University
Environmental Monitoring and Assessment

The concentrations of polycyclic aromatic hydrocarbons (PAHs) were analyzed in water, sediment, and biota (aquatic plant, shrimp, and fish) of Nansi Lake by gas chromatography–mass spectrometry (GC–MS). The concentrations of total PAHs were 27.54–55.04 ng L–1 in water, 80.31–639.23 ng g−1 dry weight (dw) in sediments, 20.92–192.78 ng g−1 dw in aquatic plants, and 67.3–533.9 ng g–1 dw in fish and shrimp muscles. The ratios of phenanthrene to anthracene (Ph/An), fluoranthene to pyrene (Flu/Pyr), and low molecular weight to high molecular weight (LMW/HMW) in sediment indicated that the sources of the PAHs were a mixture of pyrolytic and petrogenic contamination at most sampling sites in Nansi Lake. The composition profile of PAHs in plants was similar to that in water and animals with 2–3 ring PAHs being dominant. The 4–6 ring PAHs were the dominant PAH compounds in sediment. There is a positive correlation between sediment and aquatic plants, but their PAH composition profiles were different, implying that aquatic plant absorption of PAHs from sediment is selective and the accumulation of PAHs in aquatic plants is different. The concentration of PAHs in fish showed a positive correlation with plants, reflecting that the PAHs in fish are mainly absorbed from aquatic plants rather than directly from the water. Bioaccumulation of LMW PAHs in aquatic biota was higher than HMW PAHs. The biota-sediment accumulation factor (BSAF) values of total PAHs in the plants Potamogeton lucens Linn and Ceratophyllum demersum Linn were higher than that in most animals. The BSAF values of total PAHs in animals were in the following order: Cyprinus carpio > Macrobrachium nipponense > Carassius auratus > Channa argus. There was no significant relationship between PAH bioaccumulation and trophic levels in Nansi Lake. Risk assessment of PAHs in water, sediment, and animals indicated that the water environment of Nansi Lake is safe at present. It is worthwhile to note that benzo [a] anthracene (BaA), benzo [a] pyrene (BaP), indeno [1,2,3-cd] pyrene (InP), dibenz [a, h] anthracene (DBA), and benzo [ghi] perylene (BghiP) were detected in sediment, plants, and animals at all sampling sites, and they have potential carcinogenicity to the organisms of Nansi Lake. © 2015, Springer International Publishing Switzerland. Source

Song M.,Shandong Provincial Engineering Research Center for Geological Prospecting | Song Y.,REPUBLIC RESOURCES | Song Y.,Shandong Institute of Geological science | Li J.,Shijiazhuang University of Economics | Li S.,Shandong Institute of Geophysical and Geochemical Exploration
Geotectonica et Metallogenia

Besides the famous and extensive gold mineralization, molybdenum, tungsten, copper, lead and zinc ore mineralization are also commonly found in the eastern Shandong Peninsula. In order to delineate the metallogeny of the ore deposits, characteristics of the typical deposits, temporal and spatial relationship of the ore deposits and the plutons, sources of ore-forming material, and ore-forming conditions are studied in this paper. The results show that the age of magmatism and ore-formation is mainly concentrated in the interval of 127.6-105 Ma, and the ore-forming material was originated from crustal and mantle sources. The density and size of the gold deposits decreased eastward in the eastern Shandong Peninsula, while those of the nonferrous metal deposits increase. The dominant ore metals change from molybdenum and wolfram-copper, lead, zinc, silver, polymetallic to gold from the interior of the Weideshan-type granite to exterior. The gold deposits are commonly occurred in various wall rocks intruded by the Weideshan granite. And the gold deposits include two major types. One is the Jiaojia-type that occurs in the altered rocks commonly related to fracture zones of large and gently-dipping faults. The other is the Linglong-type which occurs as quartz veins in steeply-dipping secondary fractures. The characteristics of the nonferrous metal deposits may conclude as "the same source of metallogenic material, two kinds of surrounding rocks, three types of ore-forming structural zones, and four alteration styles". Gold and nonferrous metal deposits are closely related genetically in the eastern Shandong Peninsula. The variety of the mineralization is due to different physiochemical condition of ore-formation and location of ore occurrence. These deposits are all the products of the Yanshanian magmatism. Their isotopic ages are very similar and consistent with the age of the Weideshan-type granite. These deposits form a metallogenic series of hydrothermal deposit which is related to the Weideshan-type granite. Based on the analysis above, we conclude that magmatism, fluid activity and extensional structures are key factors for ore-formation. During the lithospheric thinning in the Cretaceous at the Eastern China, the "thermal upwelling-extensional structures" caused by the large-scale magmatism in the eastern Shandong Peninsula provided favorable spaces for mineralization. The course of ore-forming can be summarized as follows: The metallic elements extracted by the magmatic fluids related to the Weideshan-type granite and the mantle-derived fluids, formed the molybdenum, molybdenum-wolfram and lead-zinc deposits of porphyry-skarn type. Whereas the metallic elements extracted by the compound fluids, which are composed of the magmatic fluids, the activated fluids of surrounding rocks and the mantle-derived fluids, formed the altered rocks type and the quartz vein type gold deposits and the vein-type polymetallic deposits. © 2015, Science Press. All right reserved. Source

Han Z.,Shandong University of Science and Technology | Zhang X.,Shandong University of Science and Technology | Chi N.,Shandong Institute of Geological science | Han M.,Shandong University of Science and Technology | And 3 more authors.
Carbonates and Evaporites

This study illustrates features of the Cambrian oncoids and provides a comparison with other microbial-related carbonate grains found in the Cambrian succession of the North China epeiric platform. Based on cortex structures, four types of oncoids were distinguished: thin-cortex (superficial) oncoids, laminated-cortex oncoids, clotted-cortex oncoids, and full-cortex (without nucleus) oncoids. Thin- and clotted-cortex oncoids are often associated with oolites, laminated-cortex oncoids are present within oolitic-bioclastic grainstones, and full-cortex oncoids occur in bioturbated wackestones. The oncoids with nucleus–cortex structures are easily distinguished from other carbonate grains due to the lack of nucleus–cortex structures, and from microbial-related ooids which have more circular shape and more continuous cortex than oncoids. Oncoids without nucleus and with only crudely laminated cortex (i.e., full-cortex oncoids) can be differentiated from microbialite intraclasts and microbial lumps by the following evidences: (1) microbialite intraclasts, either rounded or angular, are characterized by margins that sharply truncate the included calcified microbes or carbonate grains and, in addition, intraclast-bearing conglomerates commonly show clear sedimentary structures such as cross-stratification and normal grading; (2) microbial aggregates have irregular but smooth margins, and rather chaotic inner structures. © 2014, Springer-Verlag Berlin Heidelberg. Source

Wang K.,China University of Mining and Technology | Wang K.,Shandong Institute of Geological science | Li N.,Shandong University | Yu X.,Shandong Institute of Geological science | And 2 more authors.
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae

In consideration of the eco-environmental status and the societal and economical characteristics of Shandong Peninsula, the ecological carrying capacity (ECC) evaluation index system based on 25 indexes was set up by using the pressure-state-response (P-S-R) concept model. The index weight was firstly defined according the analytic hierarchy process (AHP), and ECC of 6 cities in Shandong peninsula in 2009 and 2012 was then estimated by fuzzy comprehensive evaluation method. The result indicates that: (1) The ECC of Weihai was excellent (Grade I) and kept improving year by year; (2) The ECC of Qingdao, Yantai, and Rizhao were good (Grade II). ECC valuation of Qingdao and Yantai rose steadily from 2009 to 2012, but Rizhao dropped slightly; (3) The ECC of Weifang was medium (Grade III) and the ECC valuation dropped slightly year by year; (4) The ECC of Dongying rosesteadily (from Grade IV to III) from 2009 to 2012. By analyzing the ECC of each city, this study provides a scientific basis for ecological development. Source

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