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 | Year: 2015
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.
Zhang K.,Chinese Academy of Geological Sciences |
Zhang K.,CAS Institute of Geology and Geophysics |
Wei W.,Beijing University of Technology |
Lu Q.,Chinese Academy of Geological Sciences |
And 2 more authors.
Exploration Geophysics | Year: 2016
To solve the problem of correction of magnetotelluric (MT) static shift, we quantise factors that influence geological environments and observation conditions and study MT static shift according to 3D MT numerical forward modelling and field tests with real data collection. We find that static shift distortions affect both the apparent resistivity and the impedance phase. The distortion results are also related to the frequency. On the basis of synthetic and real data analysis, we propose the concept of generalised static shift resistivity (GSSR) and a new method for correcting MT static shift. The approach is verified by studying 2D inversion models using synthetic and real data. © 2016 ASEG.
Yang L.-Z.,Shandong Institute of Geological Survey |
Qu W.-L.,Qingdao Geo engineering Exploration Institute |
Zhang Y.,Shandong Institute of Geophysical and Geochemical Exploration |
Liu C.-H.,Shandong Institute of Geological Survey
Acta Geoscientica Sinica | Year: 2013
Aimed at solving the geo-environmental problems such as land subsidence resulting from continuous falling of water table due to over-exploitation, the authors selected the area of deep groundwater in Dezhou City as the key study area and took water chemical composition and environmental isotopic information as the study targets to discuss origin and refreshing capacity of deep groundwater. The results show that deep groundwater in Dezhou was mainly derived from precipitation in the last glacial period characterized by cold climate. During its formation, it had the characteristics of leaching and was affected by evaporation and cation exchange action. Later, it was interfered by many times of seawater invasion. It was dominated by HCO3-Na type water characterized by high fluorine, high sodium, low calcium and alkalescence, together with low concentrations of hydrogen and oxygen isotopes and low tritium content. The deep groundwater in Dezhou is recycled slowly and its refreshing capability is weak.
Yang L.,Shandong University of Science and Technology |
You C.-A.,Shandong University of Science and Technology |
Zhao Y.-H.,Shandong Institute of Geophysical and Geochemical Exploration |
Gou W.-L.,Shandong University of Science and Technology |
Liu Q.-N.,Shandong University of Science and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2015
The U-steel yieldable support is used in the coal roadway, which is difficult to be supported, due to its characteristics of high retaining ability, contractible capacity and convenient application. However, its own limitations of high cost, poor stability and harsh compressive conditions are difficult to be overcome, which results in its limited application. In order to solve these problems, a grille-yieldable support is proposed, and its internal force characteristic and the mechanical response caused by the yielding under the load are investigated through mechanical calculation, experimental research and numerical simulation analysis in this paper. The results show that this grille-yieldable support has a reasonable structure and a satisfactory performance on bending resistance and torsion resistance. Besides, its stability and bearing capacity are improved to a large extent. During the yielding of the support, the internal force tends to be uniform while the yielding resistance is gradually added. Due to the simplex yielding condition, it is ease to guarantee the support yielding steadily so as to avoid a sudden failure caused by buckling instability. The grille-yieldable support has many advantages such as light weight, low cost, abundant material source and easy manufacturing. In addition, it is convenient to operate with the bolt-shotcrete support, therefore, the grille-yieldable support is a practical roadway supporting form which has a great application prospect. © 2015, China Coal Society. All right reserved.
Yu Z.H.,Ocean University of China |
Gao Y.H.,Shandong Institute of Geophysical and Geochemical Exploration |
Zhai S.K.,Ocean University of China |
Liu F.,Ocean University of China
Science China Earth Sciences | Year: 2012
A sediment core H9 collected from the middle of the Okinawa Trough was studied by sequential leaching to indentify the hydrothermal component from the various other components such as detrital, biogenic, and so on. The elements were partitioned into five fractions: exchangeable, bound to carbonates, bound to iron and manganese oxides, bound to organic matter, and residual. The contents of elements Al, Ti, K, Fe, Mn, Pb, Co, Cu, Ni, and V in each fraction were determined and their percentages were calculated. Residual fraction is a dominant speciation for most studied elements except for Mn and Pb in the core sediments. For the elements Al, Ti, and K, residual fraction accounts for more than 95% of the total metal concentration. The concentrations of all studied elements in the exchangeable fraction, carbonate fraction, and organic fraction are relatively low. The metal levels in the iron and manganese oxide fraction are relatively high and this fraction represents another prevalent speciation. Also in this fraction, the metal concentrations and percentages are higher in the core section above 80 cm than those below 80 cm. Especially for Mn and Pb, the fractions bound to iron and manganese oxides account for more than 50% of the total metal concentration for the upper 80 cm section. Hydrothermal components mainly occur in this fraction. And the downcore variations of metal contents and percentages reflect the variations of hydrothermal inputs to the sediments. The high metal levels in the upper core indicate the enhancing influence of hydrothermal activities around on the core H9 during its late stage of sedimentation. The accumulation rates of hydrothermally derived Fe, Mn, Pb, Co, Cu, Ni, and V were evaluated based on their concentrations in the iron and manganese oxide fractions in this study. The results show that the accumulation rate of hydrothermally derived Mn is similar to those obtained from the Mid-ocean Ridges and Lau Basin. However, hydrothermally derived Fe and Cu present a relatively lower level. © 2011 Science China Press and Springer-Verlag Berlin Heidelberg.
Zhang K.,Chinese Academy of Geological Sciences |
Yan J.Y.,Chinese Academy of Geological Sciences |
Lu Q.T.,Chinese Academy of Geological Sciences |
Wei W.B.,Beijing University of Technology |
And 3 more authors.
Acta Petrologica Sinica | Year: 2014
In order to understand the deep structure of lithosphere more comprehensively and objectively in Nanjing (Ning)-Wuhu (Wu) and explore lithospheric thermal structure and crust, mantle status and other important scientific issues, and provide the basis for ore district mineralization and metallogenic regularity, we finish 6 MT profiles and discuss the "apparent three-dimensional" conductivity structure of crust-upper mantle through imaging studies. Find that a big low-resistivity layer exists in crust-upper mantle, and the layer is substantially continuous, but disconnects in Chaohu fold belt region. Combined with regional heat flow results, we believe that the lower crust-upper mantle is conductive, and "melt" or "aqueous shear fracture" may be existed, and the state of matter is likely to be hot and weak. In addition, we infer the location of upper mantle uplift and distribution range of the Yangtze River deep fault through the material and electrical properties, and we consider that the Yangtze River fault is not only exist, but also composes by a number of faults, and the faults is more complex and deep in the north.
Song M.,Bureau of Mineral Resources |
Wan G.,Shandong Institute of Geophysical and Geochemical Exploration |
Cao C.,Shandong Institute of Geophysical and Geochemical Exploration |
He C.,Shandong Institute of Geophysical and Geochemical Exploration
Acta Geologica Sinica | Year: 2012
Integrated gravitational, electrical-magnetic surveys and data processing carried out in the Sanshandao-Jiaojia area, Eastern Shandong Province, northeast China, aim to illuminate the geological characteristics of this shallow-covered area and delineate deep-seated gold prospecting targets. In this region, altogether 12 faults exert critical control on distribution of three types of Early Precambrian metamorphic rock series, i.e. those in the metamorphic rock area, in the granitic rock area underlying the metamorphic rock, and in the remnant metamorphic rock area in granites, respectively. Additionally, the faults have major effects on distribution of four Mesozoic Linglong rock bodies of granite, i.e. the Cangshang, Liangguo, Zhuqiao-Miaojia and Jincheng granites. The Sanshandao and Jiaojia Faults are two well-known regional ore-controlling faults; they have opposite dip direction, and intersect at a depth of 4500 m. Fracture alteration zones have striking geophysical differences relative to the surrounding county rocks. The two faults extend down along dip direction in a gentle wave form, and appear at some steps with different dips. These steps comprise favorable gold prospecting areas, consistent with a step metallogenic model. Six deep-seated gold-prospecting targets are delineated, i.e. Jincheng-Qianchenjia, Xiaoxizhuang-Zhaoxian, Xiyou-Wujiazhuangzi, Xiangyangling-Xinlicun, Panjiawuzi and Miaojia-Pinglidian.
Ni Z.,Institute of Geological Survey |
Li X.,Institute of Geological Survey |
Wen G.,Shandong Sixth Exploration Institute of Geology and Mineral Resources |
Ma Z.,Shandong Institute of Geophysical and Geochemical Exploration |
Wang Q.,Institute of Geological Survey
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2013
Based on 'metallogenetic series of mineral deposits' proposed by Chen Yuchuan, authors pick up five key prediction factors and establish regional predicting models combined with metallogenetic characteristics from typical deposits. By the methodology of deposit modeling and integrated geological information, four essential gold ore-forming factors are concluded, which are Mesozoic Linglong admellite and Guojialing granodiorite, ore-controlling and ore-forming factors caused by extensional tectonic environment under intensive subduction settings, Jiaodong intrusive rock within Jiaodong tectonic magma belt under magma arc tectonic background in continental margin, as well as NNE and NE ductile and brittle fault belt. The important ore-controlling factors of gold deposits are presented as follows, Jiaodong superficial rock system and Early-Paleozoic subducted additional complex, late-Yanshanian mineralization, natural gold and pyrite assemblage, and wall-rock alteration of potassium and beresitization. Besides, there are four clues indicating gold deposit, including regional gravity-magnetic anomalies, aeromagnetic anomalies, stream sediment anomalies and natural placer mineral anomalies. Authors used predicting models to plot prediction zone relying on integrated predicting factors. The boundaries of prediction zone are defined by ore-bearing texture, gold geochemical exploration, placer mineral abnormal features, gravity anomaly gradient belt, favorable magnetic field, etc. Moreover, the deep boundaries are further confirmed by the accurate scope of controlling-ore texture, controlling depth of proved ore bodies and possible extensional features of deep ore bodies. Total 63 predicting potential regions are proposed, including 17 A-grade ones, 11 B-grade ones and 35 C-grade ones. In addition, gold potential resources of total prediction zones are estimated quantitatively, which are 3 250 tons in less than 2 km depth according to different area, segment, depth and grade respectively.
Song M.-C.,Bureau of Mineral Resources |
Song M.-C.,Shandong Engineering Research Center for Geological Exploration |
Jiao X.-M.,Bureau of Mineral Resources |
Jiao X.-M.,Shandong Engineering Research Center for Geological Exploration |
And 5 more authors.
Geology in China | Year: 2016
The Jining Group is concealed low-grade metamorphosed strata in western Shandong Province. Based on isotopie ages and micropaleoplants analysis, combined with regional stratigraphie correlation and iron formations correlation, this paper discusses formation age of Jining Group. Results of isotopie age determination show that the genesis of zircon grains in dacite is complex, the upper intercept age of 7 points from 16 zircon analyzed points is 2522±7 Ma and the youngest age is 2487±7 Ma. In 30 pieces of rock samples, 11 samples were found to contain the microplants, which are mainly lower diversity simple spherical acritarchs, such as Leiosphaeridia, Trachysphaeridium and Stictosphaeridium. After comparison, it is considered that stratigraphie characteristics and metamorphic grade of Jining Group are similar to features of Proterozoic and Mesoproterozoic strata in North China, and are different from things of Neoarchean strata. Characteristics of seam of iron ore in Jining Group are unlike Neoarchean BIF in western Shandong Province and North China Craton; nevertheless, they are very similar to features of Yuanjiacun BIF in Shanxi Province. Synthetic analysis shows that Jining Group was formed in the transitional period from Archaean to Proterozoic. The thorough study is helpful to understanding the evolution of the regional geological environment in Archaean-Proterozoic period.