Abstract:The Gongdanshan block in Yishui County, Shandong Province, is a gneiss-granite dome. In the center of the dome, charnockites and supercrustal rock sequences (restites) of granulite facies are exposed widely; outwards to the northern, eastern and southern margins of the dome, there occur gneisses, amphibolite and granitoids in which leucocratic felsic veins and pegmatites are common. The granulite facies supercrustal rocks contain very few or almost no fluid inclusions; in contrast, the anatectic veins contain abundant CO2-rich fluid inclusions, a small number of H2O and CO2-H2O inclusions and occassionally saline aqueous inclusions with solid(s). Microthermometry and laser Raman microprobe analyses have shown that the CO2-rich inclusions contain 70～85 mol.% CO2 with minor H2S, SO2, CH4 and H2O. The early CO2-rich inclusions have higher densities while the CO2-rich inclusions distributed along the transgranular fractures have lower densities. H2O (aqueous) inclusions belong to the products of late retrograde metamorphism after peak metamorphism. The vapor-rich inclusions of low-density are probably related to leakage or partial decrepitation of CO2 (±H2O) inclusions. The role of fluid during anatexis is tentatively discussed. It is suggested that under the pressure of the middle crust the infiltration of a CO2-H2O fluid along foliations of fissures of rocks would cause partial melting that led to the formation of garnet or orthopyroxene, with H2O entering the melt preferentially and CO2 entering the coexisting vapor garnet and/or pyroxene porphyroblasts and in quartz within felsic veins crystallized subsequently from the silication melt. The P-T conditions the rocks experienced after peak metamorphism are deduced from the mineral equilibria and the microthermometry of the fluid nclusions

Abstract:This paper has established six ground_space correlation models based on a study of ground spectrum property of kimberlites in Mengyin area. The TM correlation analysis of ground spectra of kimberlites led to the transformation of the TM image for the middle part of Yishu Fault zone into a ground space correlation image related to the ground spectrum property of kimberlites in Mengyin area. The application effects of the ground-space correlation image for the prognosis of diamond deposits in the middle part of Yishu Fault zome are also discussed in this paper. Through the analysis of the ground-space correlation image, the authors recognized six image anomalies related to the kimberlites. During the field inspection of the anomalies, some carbonate veins were discovered within A-1 and A-2 anomalies. Heavy mineral, isotope and REE studies suggest that this sort of carbonate veins might be a kimberlite which experienced late carbonate alteration.

Abstract:The metamorphic unit Xiaoqingshan Formation in Xiaoqingshan Cu(Au) deposit, Huili County, mainly consists of garnet-sericite phyllite, sericite-quartz phyllite, sericite-quartz phyllite, sericite phyllite, carbonaceous slate and a small amount of albite-actinolite schist. The chloritoid phyllite was considered to be the main component of the formation. Nevertheles, the authors consider that this kind of rock belongs to retrograde garnet-sericite phyllite. The metamorphism of the formation can be divided into three stages: M1, M2 and M3, in terms of the evolution of the texture of the rocks and the relatiohships between the minerals of the rocks.There exists compositional distinction between the core and the rim of the garnets from the garnet_sericite phyllites. Spessartine and almandine make up 29.22%～33.55% and 43.28%～48.86% respectively in the core and 8.65%～17.08% and 60．55%～70．66％ respectively in the rim. Muscovites of two genetic stages, Mus1 and Mus2, have been distinguished. There are three genetic kinds of chlorite in the rocks, formed at three stages respectively.The T and Pconditions of the three metamorphic stages were calculated by means of geothermometers and geobarometers, being 500～550℃, 0.6～0.75 GPa for M1, 400～430℃, 0.3～0.5 GPa for M2, and 280℃， 0.3 GPa for M3. The authors have established the P-T-D path about the metamorphism and deformation of Xiaoqingshan Formation. It seems to be a clockwise one.Based on the T and P conditions of the formation in the area, it is considered that the copper and gold deposit hosted in the formation was replaced by deep-seated Na-, Cu- Au- bearing fluids. It occurred much later than instead of during the metamorphism.

Abstract:The whole rock and mineral Rb-Sr isotopic dating suggests that the Xinhuatun pluton located in Zhangguangcailing of Northeast China was emplaced in Middle Jurassic with isotopic ages of 160～165Ma, rather than belonging to Indosinian. Geochemical studies indicate that this pluton is of fractionated felsic I-type and experienced slight contamination by crustal material during its emplacement and crystallization. However, the major factor responsible for chemical variation seems to have been mineral fractionation. The young Nd model ages suggest a significant crustal growth in the period of Neoproterozoic-Phanerozoic.

Abstract:Manzhouli area is an important metallogenic province of Yanshanian porphyry-subvolcanic vein-epothermal mineralization series. The granites of the earlier stage serve as the main country rocks for ore depostis. It has always been questioned whether Indo_sinian granite exists or not in this area. In the adjacent area within Mongolia and Russia and in the Da Hinggan Mountains to its east there are Indo-sinian granites, but in Manzhouli-Xiqi area, Triassic synthem has not beens eparated out, and no definite age evidence has been sugggested.Some systematic petrological-mineralogical and Rb-Sr isotopic geochronological studies were carried out on the early stage granites from four major ore districts,which were previously considered to be late Hercynian or early Yanshanian. Two Rb-Sr isochron ages (225±7.9 Ma and 211±21Ma)obtained in this study show fine linear correlation,suggesting the existence of Indosinian granites. A considerable portion of originally-defined late Hercynian and early Yanshanian granites should be reassigned to Indosinian

Abstract:Compact and hard authigenic calcite was discovered in the surface sediments at the water depth of 530 m on the eastern slope of the Okinawa Trough. It has brown color and biological shapes, and occurs as infilling materials in microbiological crusts, most of which were formed in foraminifera and gastropoda, and a few of which were formed in lamellibranch. Less calcite occurs as fecal pellet. Analyses of mineral and chemical composition as well as carbon and oxygen isotopes were carried out with X-ray diffractometer, electron microprobe, neutron activation and mass spectrograpgh respectively. The analytical results indicate that the iron content of calcite ranges from 0.19%～13.43%(mostly over 9%), with an average of 7.18%, much higher than the content of magnesium, suggesting ferrocalcite calcite; magnesium content is from 3.36% to 5.56%, averagely 4.9%. The calcite contains relatively high Si, Al, K, Na and Sr (1800 μg/g). Ferrocalcite coexists with magnesian calcite as solid solution. There are obvious correlations between most elements. It is worth mentioning that Fe is correlated not only with Si, but also with Si, Al, K and Na. The facts that the Al/Si ratio of ferrocalcite is similar to that of clay minerals and that no clay peaks have been found on the X-ray spectral lines indicate that Al, Si, K and Na in the calcite exist in the form of amorphous clay, which plays a role of filter in the enrichment of iron. δ13C(2.3‰) and δ18O(1.4‰) of the calcite fall between shallow water calcite and deep sea calcite, whereas δ13C(1.5‰)and δ18O(0.3‰) of the shells fall within the range of shallow water mollusk and foraminfera. Crystal and chemical characteristics offerrocalcite, suchas hexagonal system, relatively high content of Sr and isotopic composition of carbon and oxygen, show that the biochemical process play an important role in the formation of ferrocalcite. In addition to physical and chemical conditions in the sedimentary environment, the formation of ferrocalcite presumably has close relation to shells in which beneficial microenvironment has been formed. 

Abstract:Systematic hydrogen and oxygen isotope studies of large-size and middle-size gold deposits in Jiaodong area show that primary mineralizing fluids were mainly made up of magmatic water. In the forming course of remelting granite, some metamorphic water was inherited. At the high temperature stage, mineralizing fluid was mainly magmatic water, which then tended to evolve into meteoric water. Only a few mineral deposits are of meteoric water origin. Application conditions of H. P. Taylor's equation on isotope exchange are discussed in this paper. It is pointed out that the equation fails to give a definite answer when the water/rock ratio is small. Rb-Sr isochron curve dating of fluid inclusions indicates that gold matallization occurred in Yanshanian stage, and that the ISr of mineralizing fluids in not different from that of Guojiadian and Guojialing granite.

Abstract:Recent progress in the study of selenium minerals has been briefly summed up in this paper with a lost of selenium minerals formally approved by IMA CNMMN. The elemental composition and modes of occurrence of selenium minerals and the achievements acquired in selenium mineralogy of China have also been described. Finally the problems concerning the further studies of selenium mineralogy and geochemistry are discussed.

Abstract:The surface modification of minerals has been studied by infrared spectrum (IR)before. It is usually suggested that surface modification is completed if the organic group absorption, such as -CH2 or -CH3, appears in the IR spectrum of modified samples. Nevertheless, this method only tells us that the coupling agent exist in the samples, but fails to tell us whether the coupling agent molecules are really linked to the ions on the surface of the minerals or not. This paper tries to study the surface modification of fired kaolin by using MAS NMR on the basis of the following consideration: if the ions on the surface of minerals are linked with the coupling agent molecules, it can result in the change of such chemical environments around the ions as charge density, which can be detected by MAS NMR technique. The sample from the tonsteins in the coal-bearing strata where the kaolinite content is up to 90% is ground to 1250 mesh and fired in an oven at 950℃ for 12 hours. The fired kaolin is modified by silane coupling agent under a certain program.The comparative study on the 29Si and 27Al MAS NMR of modified and unmodified fired kaolin shows that the chemical shift of -106×10-6of 29Si is unchanged between modified and unmodified samples, but 27Al changes obviously. The chemical shift of 5.44×10-6 and 65.69×10-6 of 27Al in unmodified samples are separately shifted to 3.8×10-6 ～ 4.4×10-6 and54.6×10 -6 ～59.9×10-6 after modification. This result shows that the modification is completed by linking Al on the surface of fired kaolin with the silane coupling agent molecules.

Abstract:Based on homogenization temperature and duration of homogenization process obtained from Johannes (DH=r2/4t) and Eyring equations (DN=KB·T /η·λ), the authors calculated the viscosity of a melt inclusion at homogenization. The water content of the inclusion melt was estimated from the experimental diagram LnDH-1/T for granitic melt with different water contents. The study on mineral inclusions from Luanjiahe granite in Jiaodong gold zone indicates that the melt inclusion has a homogenization temperature of 970℃, viscosity of 3.8×106 Pa·s and water content of 2.5%, whereas the fluid_melt inclusion has a homogenization temperature of 855℃, viscosity of 617.7 Pa·s and water content of 5.8%, suggesting that during the crystallization of granitic magma water content increased while viscosity decreased continuously, and at the late stage of crystallization the fluid was close to the saturation state.

Abstract:Studies of kaolins from Shange with EPR technique indicate that the iron in kaolins exists in two forms: structural Fe3+ ion, which is isomorphously substituted for Al3+ion in the octahedral sheet in kaolinite and free Fe3+ ion, which exists in hematite, limonite and geothite. Structural iron which exists in the octahedral sheet occupies two distinct substitutional sites (I and E). The I iron is due to Fe3+ion at a site having orthorhombic symmetry, and the E iron is due to Fe3+ion at a site of higher symmetry. The structural iron content is 0.081%～0.122% Fe2O3 (I iron 0.031%～0.055%, E iron 0.050%～0.067%). The free iron content is 0.467%～0.648% Fe2O3. It is concluded that the content of I iron and that of E iron are both correlated inversely with the X-ray crystallinity of kaolinite, whereas the ratio of E iron content to I iron content is correlated directly with the degree of order of kaolinite. Chemical bleaching fails to affect structural iron, but can remove most of free iron from kaolin.

Abstract:This paper presents a new viewpoint that the differential diffusion velocities control crystal forms in accordance with the different influences of crystallized ions in the course of mineral crystallization, and that the generation of differential diffusion velocities is attributed to the reason that the concerted effects of external factors (consistency, temperature, pressure, pH, viscosity etc.) cause the differences in diffusion velocities of different ions and that the differential diffusion velocities of different ions lead to produce occupancy selection and dominant net in the course of mineral crystallization. The crystal form results from concerted effects of all external factors and the result, in turn, can reflect physical_chemical conditions for mineral crystallization. It is the differential diffusion velocity of each ion that controls occupancy selection and leads to form dominant net and then form crystal shape that can reflect the differential diffusion velocity of each ion. If we probe into morphological typomorphic characteristics of crystals and study physical_chamical conditions of mineral crystallization by ascertaining dominant net and analysing external factors that affect diffusion velocity, we can comprehensively consider all influences of external factors and avoid partiality enumerated in this paper. Furthermore, morphological typomorphic characteristics of such minerals as pyrite and fluorite are surveyed on the basis of differential diffusion velocity. In addition, the manner of growth of crystal and relationship between relative intensity of powder diffraction and dominant net are discussed in this paper.