bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluid Inclusion Studies and Geochemistry of Rare Earth Elements of Hydrothermal Fluorites from Pöhrenk, Kirşehir, Central Turkey
Authors: KOÇ Şükrü , REÇBER Ali 
Published: September 2010

AbstractFluorite mineralization occurs along fractures and cracks of Middle Eocene and Pliocene limestones and marls in the north and northeast of the Pöhrenk region (Çiçekdagi, Kirsehir). Tb/Ca – Tb/La and Y/Ho ratios were obtained from REE contents of fluorites which have revealed that mineralization is of hydrothermal type. Negative Ce anomalies and positive Eu anomalies reflect that hydrothermal solutions once had high oxygen fugacity. Fluid inclusion studies indicate that homogenization temperatures of mineralization varied between 90°C and 200°C, and hydrothermal solutions are composed of NaCl + KCl + MgCl2 + H2O. In addition, salinity measurements show that hydrothermal solutions were mixed with meteoric or rock formation water. Geologic setting, REE geochemistry and fluid inclusion studies suggest that mineralization was deposited from a solution generated by mixing of magmatic and meteoric water under epithermal conditions.
Analysis of Ore‐controlling Structure in the Qifengcha‐Detiangou Gold Deposit, Huairou County, Beijing
Authors: Bailin CHEN , Zhongjian LI , Faxian DONG 
Published: September 2010

AbstractThe Qifengcha‐Detiangou gold deposit is a medium‐sized deposit recently found in Huairou County, Beijing. It belongs to the altered mylonite type with superimposed quartz vein type and is related to the early Yanshanian magmatic activity. Characterized by multiperiodic activity, the NE‐trending Qifengcha fault is a regional ore‐controlling structure in the area, and gold mineralization develops only in its southeastern part. Meanwhile, gold mineralization is controlled by the Yunmengshan metamorphic core complex. The nearly N‐S‐ and E‐W‐trending low‐angle detachment faults, reformed by the Qifengcha fault in the northwestern part of the core complex, are the main ore‐bearing faults. All discovered gold deposits are located within an area 1.5–4.0 km away from the boundary of the upwelling centre. The N‐S‐ (NNE‐) and E‐W‐trending ore‐bearing faults are ductile‐brittle structural zones developing in shallow positions and subjected mainly to compressive deformation. The structural ore‐controlling effects are as follows. (1) The attitude, shape, and distribution of gold orebodies are controlled by faults. (2) There is a negative correlation between the gold abundance and the magnetic anisotropy (P) of the altered mylonite samples from the deposit, which shows that the gold mineralization is later than the structural deformation. (3) Quartz vein type mineralization is superimposed on altered mylonite type mineralization. (4) In mineralized mylonite, the stronger the ductile shear deformation, the easier the late‐stage gold mineralization to occur and the higher the gold abundance. The richest gold mineralization occurs only around the centre of the fault subjected to the strongest deformation.
Fluid‐melt Inclusions in Fluorite of the Huanggangliang Skarn Iron‐Tin Deposit and Their Significance to Mineralization
Authors: Lijuan WANG , Jingbin WANG , Yuwang WANG , Qian MAO 
Published: September 2010

AbstractFor the first time, fluid‐melt inclusions are found in fluorite of the Huanggangliang skarn iron‐tin deposit (HSID). The fluorite was formed in the main stage of mineralization, named the hydro‐skarnization stage. The inclusions contain various components such as Fe, Mg and Cr from deep sources. The melts of primary inclusions are mainly Ca‐ and F‐rich and those of secondary inclusions tend to become Si‐rich. During this evolution process, the melts and iron daughter minerals decreased and even vanished. These facts reveal that the evolution of the primary mineralizing fluids and the differentiation of the fluids and melts are the main factors leading to the deposition of Fe, Sn and other elements. This discovery confirms the magmatic genesis of the HSID and has filled in the gaps in the research of magmatogenic skarn deposits and furnished new methods for such research. Furthermore, it has enlarged the scope of the research on fluid inclusions.
Rational Exploitation of Resources and Prevention of Geohazards in Karst Regions
Authors: Yaoru LU , Xiling Edited By Zhu 
Published: September 2010

AbstractThis paper discusses the rational exploitation of main resources and prevention of geohazards in karst regions. There exist relationship chains between natural disasters in the earth, which include the chain between geological hazards and climatic hazards, the chain between geological hazards and biogenic hazards as well as the one between geological hazards. Irrational exploitation of all resources will inevitably cause hazards. Therefore it is very important to discuss the problem related to prevention of geohazards by rational exploitation of resources.
Evaluation of Karst Hazards for Civil and Industrial Buildings
Authors: TOLMACHEV V.V. , NESHCHETKIN O.B. 
Published: September 2010

AbstractThe European part of Russia exhibits highly developed sulphate and carbonate karst. It mostly occurs within river valleys with relatively thin covering deposits. These conditions may induce karst collapses, which appear to be the main danger for civil and industrial buildings. Evolution of karst rocks includes several epochs of karst development, which causes complicated distribution of karst caves in karst rocks and, as the result, irregular distribution of karst caves on the surface. Karst hazards prediction is mostly reliable within the geotechnical system “Karst‐Construction”, using probability methods. This approach allows creating 3 types of antikarst protection (alternative design of construction arrangement on a plan, structural protection of a construction and plugging of karst caves beneath construction foundation) and selecting the optimum or the most effective version or their rational combination.
Engineering‐Geological Problems in the Moravian Karst, Czech Republic
Authors: ŜAMALIKOVA Milena 
Published: September 2010

AbstractThe Moravian karst belongs to one of the famous karst regions in Central Europe. It is situated in Moravia in the eastern part of the Czech Republic. According to the geology it is of Devonian age and the main rocks are of different types of limestones. The process of karstification is still active. They are many caves with rich stalagmites and stalactites and the Macocha abyss, the depth of which is 138.5 m. The underground Punkva River flows through the main part of the karst, forming beautiful underground lakes. Typical karst phenomena, such as sinkholes and deep canyons, may be observed on the surface of the terrain. Because of the karstification, water erosion and frost weathering, many steep unstable slopes and walls originated. To solve the stability from a geotechnical point of view is not easy. This requests a special engineering‐geological knowledge and experience.
Palaeoseismic Events in Karst Terrains along the Northern Bulgarian Black Sea Coast
Authors: ANGELOVA Dora 
Published: September 2010

AbstractThe study of the palaoseismic events in the karst terrains of the Bulgarian Black Sea coast is a very important up‐to‐date problem. The investigated region is one of the highest‐energy regions in Bulgaria with established and recorded catastrophic historic and contemporary earthquakes. The terrain is subjected to the influence not only of its own earthquake foci but also of those in Romania and Russia. The palaeoearthquakes that caused considerable disturbances in the karst terrains along the Northern Bulgarian Black Sea coast have left significant traces. They caused disturbances in the environment and the relief (rearrangement of the surface and ground water karst basins, partially or entirely collapsed caves, deformed caves, oil, gas and salt intrusions and gravitationally formed caves). The ecological consequences in historic and contemporary aspects were catastrophic. The palaeoseismic dislocations were formed as a result of global, regional and local geodynamic events related with the destruction of the Moezian platform and the regional extension of the Black Sea basin. The time of their display and their spatial interrelations were established as a result of complex investigations accompanied by original documents.
Study of Sediments in the Yutian‐Hotan Oasis, South Xinjiang, China
Authors: Baosheng LI , ZHANG David Dian , Xingjia ZHOU , Feng ZHU , Baoyin YUAN , Guijin MU , Sen LI , Mancun YAN , Heling JIN , Quanzhou GAO , Wu SUN 
Published: September 2010

Abstract  Based on investigation of sediments in the Yutian‐Hotan Oasis at the southern margin of the Tarim basin, 14C ages and grain‐size and chemical element analyses, the following views are put forward in this paper.

Sediments in the Yutian‐Hotan Oasis are composed chiefly of “oasis soil”, similar to the recent oasis soil, i.e. brown desert soil, which was formed due to pedogenesis after aeolian sand (sandy loam) and dust (loess) of 3.32–6.64ϕwere deposited.
The ancient Yutian‐Hotan Oasis represented by oasis soil was formed at 13000 a B.P. During the cold period of the past 13000 years, this region is characterized mainly by accumulation of sand and dust storms, and sandy oasis soil was developed in this region due to pedogenesis in an oasis environment; during the warm period, dust falls predominated along with certain current concomitants (lacustrine facies), and silty oasis soil was formed by pedogenesis. Owing to fluctuations of cold and warm climates since 13000 a B.P., sandy oasis soil was deposited alternately with silty oasis soil and lacustrine soils. Nevertheless, the Yutian‐Hotan Oasis has been preserved and developing continuously towards the contemporary time.
At the latest, the oasis became an important site of human inhabitancy at 10000 a B.P., and since then it has been an important base for the propagation and activity of local people in the Tarim Basin.
Fractal Principle of Mineral Deposit Size Forecasting and Its Implication for Gold Resource Potential Evaluation in China
Authors: Changjiang LI , Tuhua MA , Xingsheng ZHU , Guowu WANG 
Published: September 2010

AbstractMineralization distributions are very heterogeneous in nature. As large or superlarge mineral deposits are quite rare whether in time or in space, it is difficult to detect all the largest mineral deposits in a region in a limited period of time owing to the restriction of technology and exploration degrees—this is called “not all discovered”. However, all discovered large, especially superlarge, mineral deposits generally have a complete census in the geological literatures. On the other hand, not all discovered small mineral deposits are recorded in the geological literatures because for economic reasons people have not much interest in them—this is called “not all recorded”. This practice often results in the observation truncations, that is, the data points near the two ends in an observable population, which is obtained by fitting a power law size‐frequency distribution to discovered mineral deposits in a given region, show concave‐down departure from the correlation line fitted. The authors suggest that the size and number of undiscovered deposits may be forecast by fitting a fractal size distribution to discovered mineral deposit sizes between the upper and lower truncation observations and then extrapolating the scale‐independent area to deposit sizes larger than the upper truncation limit. Based on the statistical results obtained by the fractal size‐frequency distributions of 394 discovered gold deposits with sizes greater than 2 t Au in China and 83 known gold deposits with sizes over 0.3 t Au in the Jiaodong area of China, the authors forecast according to the present commercial standards for gold ores that the total resources of undiscovered gold deposits ranging in tonnage from 50 to 2000 t Au are more than 4500 t in China, and that in the Jiaodong area of China the total resources of potential gold deposits with sizes in the range of 30 to 650 t Au are about 700 t.
Genetic Mechanism of Mineral Inclusions in Zircons from the Khondalite Series, Southeastern Inner Mongolia
Authors: Fulai LIU , Qihan SHEN 
Published: September 2010

Abstract  The early Precambrian khondalite series is widely distributed in the Jining‐Zhuozi‐Fengzhen‐Liangcheng area, southeastern Inner Mongolia. The khondalite series mainly consists of sillimanite garnet potash feldspar (or two‐feldspar) gneiss and garnet biotite plagioclase gneiss. These gneissic rocks have commonly experienced granulite‐facies metamorphism. In zircons separated from sillimanite garnet potash feldspar gneisses, many mineral inclusions, including Sil, Grt, Ky, Kfs, Qtz and Ap, have been identified by the Laser Raman spectroscopy. Generally, prograde metamorphic mineral inclusion assemblages such as Ky + Kfs + Qtz + Ap and Ky + Grt + Kfs + Qtz are preserved in the core of zircon, while peak granulite‐facies metamorphic minerals including Sil + Grt + Kfs + Qtz and Sil + Grt + Kfs + Qtz + Ap are identified in the mantle and rim of the same zircon. However, in some zircons are only preserved the peak metamorphic minerals such as Sil + Grt + Kfs + Qtz and Sil + Grt + Kfs + Qtz + Ap from core to rim, and in others are inherited the primary cores with minor mineral inclusions of Kfs + Qtz, with peak metamorphic mineral inclusions around the inherited cores. These data indicate that the mineral assemblage evolution of sillimanite garnet potash feldspar gneisses in the study are did experience a polymorphic transformation of kyanite to sillimanite. In garnet biotite plagioclase gneisses, secondary electron microscopic images reveal that most zircons display distinct zoning textures, which comprise cores and rims, each with distinctive inclusion assemblages. The inherited mineral inclusions, mainly consisting of Kfs + Pl + Qtz, Kfs + Qtz and Kfs + Qtz + Ap, are preserved in the primary cores, while peak granulite‐facies mineral asemblages, including Grt + Bt + Pl + Qtz + Ap, Grt + Bt + Pl + Qtz and Grt + Bt + Pl + Qtz + Rt, are identified on the rims. The occurrence of peak metamorphic mineral inclusions in zircons indicates that these gneissic rocks, including sillimanite garnet potash feldspar gneiss and garnet biotite plagioclase gneiss, have experienced granulite‐facies metamorphism.Secondary electron microscopic images of zircons from the khondalite series display distinct zoning from core to rim, and are genetically related to the primary, prograde, and peak metamorphic mineral inclusion assemblages respectively. These images reveal irregular zoning patterns and varying thickness of cores and rims. The abundance of inclusions complicates the conventional U‐Pb age dating. Therefore, the SHRIMP micro‐spot U‐Pb method is essential for the protolith and metamorphic age dating of the khondalite series, southeastern Inner Mongolia.
Models of Spatial Structures of Regional Multi‐element Geochemical Anomalies over Copper‐Polymetallic Orefields
Authors: Changyi SHI , Jinhua ZHANG 
Published: September 2010

Abstract  Regional stream sediment surveys at a 1:200,000 scale reveal positive and negative regional multi‐element geochemical anomalies over medium to large copper‐polymetallic orefields of different genetic types in China. Regional geochemical anomalies of orefield refer to those geochemical anomalies that are related to metallogenesis of an orefield in a certain area. The anomaly area is typically 10 to 100 km2. The regional multi‐element anomalies related to mineralization can be divided into three groups, that is, the ore‐element anomaly association, indicator element anomaly association, and metallogenic environmental element anomaly association. Their common spatial distributions over ore deposits or orefields possess unique structures.The model of spatial structure of regional multi‐element geochemical anomalies (RAGSS) of an orefield delineates structural feature possessed by orderly spatial distributions of different groups of multi‐element anomaly associations related to orefield metallogenesis. It is used to outline the common metallogenetic anomaly visage that is composed of the orderly spatial distribution of different groups of multi‐element anomaly associations. The orderly spatial distribution of multi‐element anomalies over an orefield reflects element distributions as they are changed from a dispersed “out‐of‐order” state into a concentrated “orderly” state during the mineralization of an orefield.Three different patterns of the spatial anomaly structure related to mineralization in an orefield can be concluded: (1) nested pattern; (2) eccentric pattern and; (3) peripheral pattern. There are marked differences between multi‐element anomaly patterns related and not related to mineralization. RAGSS models of orefields can be used to better understand and evaluate regional multi‐element anomalies and identify ore types.
Uranium Potential and Regional Metallogeny in China
Authors: Jindai ZHANG , Ziying LI 
Published: September 2010

AbstractThis paper is briefly involved in distributions of China's uranium metallogenic types, provinces, regions and belts. Eight target regions have been pointed out to be worthy of prospecting for uranium resources. The regional uranium metallogeny is discussed and great uranium potential pointed out from many aspects. Generally speaking, there are favorable conditions for uranium mineralization and good perspective to explore for uranium resources.
Geology and Genesis of the Superlarge Jinchang Gold Deposit, NE China
Authors: Guozhi JIA , Jinrong CHEN , Zhaoguang YANG , Hongye BIAN , Yangzhong WANG , Haijun LIANG , Tonghe JIN , Zhenhui LI 
Published: September 2010

AbstractThe superlarge Jinchang gold deposit is located in the joint area between the Taipingling uplift and the Laoheishan depression of the Xingkai Block in both eastern Jilin and eastern Heilongjiang Province. Wall rocks of the gold deposits are the Neoproterozoic Huangsong Group of metamorphic rocks. Yanshanian magmatism in this region can be divided into 5 phases, the diorite, the graphic granite, the granite, the granite porphyry and the diorite porphyrite, which resulted in the magmatic domes and cryptoexplosive breecia chimney followed by large‐scale hydrothermal alteration. Gold mineralization is closely related to the fourth and fifth phase of magmatism. According to the occurrences, gold ores can be subdivided into auriferous pyritized quartz vein, auriferous quartz‐pyrite vein, auriferous polymetallic sulfide quartz vein and auriferous pyritized calcite vein. The ages of the gold deposit are ranging from 122.53 to 119.40 Ma. The ore bodies were controlled by a uniform tectono‐magmatic hydrothermal alteration system that the ore‐forming materials were deep derived from and the ore‐forming fluids were dominated by magmatic waters with addition of some atmospheric water in the later phase of mineralization. Gold mineralization took place in an environment of medium to high temperatures and medium pressures. Ore‐forming fluids were the K+‐Na+‐Ca2+‐Cl−‐SO42‐ type and characterized by medium salinity or a slightly higher, weak alkaline and weak reductive. Au in the ore‐forming fluids was transported as complexes of [Au (HS)2]−, [AuCl2]−, [Au(CO2)]− and [Au(HCO3)2]−. Along with the decline of temperatures and pressures, the ore‐forming fluids varied from acidic to weak acidic and then to weak alkaline, which resulted in the dissociation of the complex and finally the precipitation of the gold.
The Structure of Ore‐controlling Strain and Stress Fields in the Shangzhuang Gold Deposit in Shandong Province, China
Authors: Jun DENG , Qingfei WANG , Liqiang YANG , Lei ZHOU , Qingjie GONG , Wanming YUAN , Hao XU , Chunying GUO , Xiangwei LIU , Xiling Edited By Zhu 
Published: September 2010

AbstractThe Shangzhuang altered‐rock type gold ore deposit is located in the middle segment of and controlled by the Wang'ershan fault zone in the northwestern part of the Jiaodong gold province, China. The deformation evolution, the structure of strain and stress fields and its ore‐controlling effect in the Shangzhuang deposit are discussed in this paper. It is revealed that the deformation evolution has mainly undergone four phases: the early ductile deformation, the second NE‐striking horizontal simple shear, the third NE‐striking compression‐shear and the final NW‐striking compression. The mineralization happened during the third stage in which the maximum principal stress gradually transited from NE to NW. The 3‐D numerical simulations of the stress field show that, on the condition that the maximum principal stress is NE‐striking, the fracture development in the fault zone is favored, while when the maximum principal stress is NW‐striking, the fault zone is relatively extensional and it is suitable for the influx and emplacement of ore‐forming fluids. The compression‐shear strain field during the mineralization is characterized by the Λ‐type structure, the positive flower structure, etc. Orebodies are mostly equidistantly located in the dilatational spaces, which are distributed in the integral compressional circumstances. And the dilatational spaces are developed where the fault attitude changes or shear joint systems develop. In the overall compression‐shear stress field, the strain field bears self‐similarity at multiple scales, including the orebody, ore deposit and orefield. The self‐similarity of the structure comprises the subequidistant distribution of fractures at the same scale and the similar shape of the fractures at various scales. Yet, due to the special geological structure, the orebodies are mostly located in the hanging wall in the Shangzhuang deposit, which is different from most deposits in the Jiaodong gold province. Analyses of the ore‐controlling stress and strain fields in the deposit provide an important basis for deposit seeking.
Isotopes and Geochronology of the Meixian‐type Pb‐Zn‐(Ag) Deposits, Central Fujian Rift, South China: Implications for Geological Events
Authors: Chengyou FENG , Dequan ZHANG , Daxin LI , Hongquan SHE , Yingjun DONG 
Published: September 2010

AbstractCentral Fujian Rift is another new and important volcanogenic massive sulfide Pb‐Zn polymetallic metallogenetic belt. In order to find out the material genesis and mineralization period of Meixian‐type Pb‐Zn‐Ag deposits, S and Pb isotope analysis and isotope geochronology of ores and wall rocks for five major deposits are discussed. It is concluded that the composition of sulfur isotope from sulfide ore vary slightly in different deposits and the mean value is close to zero with the δ34S ranging from −3.5%‰ to +5.6%‰ averaging at +2.0‰, which indicates that the sulfur might originate from magma or possibly erupted directly from volcano or was leached from ore‐hosted volcanic rock. The lead from ores in most deposits displays radioactive genesis character (206Pb/204Pb>18.140, 207Pb/204Pb>15.584, 208Pb/204Pb>38.569) and lead isotope values of ores are higher than those of wall rocks, which indicates that the lead was likely leached from the ore‐hosted volcanic rocks. Based on isotope data, two significant Pb‐Zn metallogenesis are delineated, which are Mid‐ and Late‐Proterozoic sedimentary exhalative metallogenesis (The single zircon U‐Pb, Sm‐Nd isochronal and Ar‐Ar dating ages of ore‐hosted wall rocks are calculated to be among 933–1788 Ma.) and Yanshanian magmatic hydrothermal superimposed and alternated metallogenesis (intrusive SHRIMP zircon U‐Pb and Rb‐Sr isochronal ages between 127–154 Ma).