Abstract:The Pangxidong-Jinshan silver_gold metallogenic belt,located in the border area between Guangdong and Guangxi,include a series of deposits distributed along the Pangxidong-Jinshan fault, The Late Yanshanisn granites in the belt are of Type I. The silver-gold deposits and the granites are closely related to each other, and characterized by very similar trace elements, REE and Pb isotopes and fluid composition. The Late Yanshanian magmatism may have provided part of hydrothermal solution and metallogenic materials for mineralization.

Abstract:In this paper,the authors has studied the geology, petrology, mineral chemistry, geochemistry,petrogenesis,tectonic environment of Middle Proterozoic and Mesozoic volcanic rocks from Beijing area, discussed the spatial and temporal distribution and compositional variation of volcanic rocks, analysed the acidity frequency and magma series, estimated the tectonic settings and pull-apart distance,and evaluated sources and evolutional mechanism of magma.

Abstract:The eclogites in northern Jiangsu have at least three types:high pressure crustal type (H-type), ultrahigh pressure crustal type (U-type)and mantle type (M-type).The eclogites of H_type were mainly formed in the lower crust through the low-temperature and high-pressure metamorphism of Jinning orogeny. The eclogites of U-type contain micrograined diamond, coesite and pseudocoesite and exhibit tension crack texture and normal or inverse zoning structure. The garnets consist mainly of grossular and the clinopyroxenes comprise chiefly omphacite of high jadeite, formed in the upper mantle under megatemperature and ultrahigh pressure of Indosinian orogeny. The garnets of M-type belong to pyrope mainly formed near the boundary between lithosphere and aesthenosphere under the megatemperature and ultrahigh pressure of Jinning or earlier orogeny.

Abstract:Kuluketage area is located in the northeastern margin of the Tarim basin. There are a lot of plagioclase amphibolites in the form of lens in the TTG series, with their long_axis consistent with the strike of gneissic schistosity. On the basis of detailed researches on petrology, geochemistry of REE and trace elements and Sm, Nd isotopic compositions, two types of plagioclase amphibolites have been recognized in Kuluketage area. The protolith of the plagioclase amphibolites in Tuogelakebulake area in the northern part of Kuluketage region was basalt which might have been formed in the mid-ocean ridges. The amphibolites have the flat REE pattern similar to that of MORB with (La/Yb)Nbeing 0.66—4.23 andδEu 0.82—1.15. The samples in Kuokesu area located in the southern part of Kuluketage region are characterized by the light REE-enriched pattern with (La/Yb)Nbeing 2.71—10.84 andδEu 0.81—1.07. This may indicate that plagioclase amphibolites are similar to island arc basalt. The magma of all the plagioclase amphibolites was derived from the mantle, with no crustal contamination in the process of uplifting.

Abstract:Formed by passive emplacent of crust-mantle mixed type of magma and controlled by nearly NS-trending Baodu-Boluo arcuate fault zone, theHimalayan porphyry belt in Ninglang area tends generally to plunge northward. Porphyry rocks in this belt are intermediate-acid rocks of calc-alkaline series. An integrated analysis of geological and petrochemical characteristics of varus porphyry bodies(groups) in this porphyry belt show that porphyry bodies in this belt are cupreous or copper (molybdenum) ones which have good metallogenic prospects.

Abstract:The Chinese and English names, chemical formulae and other dtat of forty two new minerals wich were approved by IMA CNMMN from January 1993 to Decembr 1993 and published by mineralogical journals of various countries are listed in this paper. These data of new minerals include their crystallographic systems, space groups, unit cell parameters, main powder diffraction dtat (I,hkl), physical properites (crystal form, color, streak, luster, cleavage, luminescence, hardness, density etc.), optical properites (uniaxial or bioxial crystal, positive or negative character, refractive index, reflectance, bireflectance, 2V, dispersion, absorbability,polychroism etc.), modes of occurrence, paragenetic minerals and references.

Abstract:The heat produced by U and Th is the main energy that leads to the evolution of the planets. At the same time, the radioactivity of U and Th also has an important effect on living beings. So it is necessary to probe the geochemical behavior of U and Th to understand the evolution history of the planets , the origin and evolution of the Earth' s crust and the evolution of living beings. In this paper, the authors have reached the following conclusions: 1. According to the physical and chemical properties of U and Th, it is considered that there are two different ways in their migration. (1) In the rocks containing volatiles with oxidation ability, such as H2O, O2, N2, F2, Cl2or their ions, the U and Th will combine with them chemically to become high valence compounds and complexes, which have an intense tendency of migrating from high to low temperature facies by magmatism and metamorphism. Because there are a lot of volatile with oxidation ability in the Earth, such as H2O, O2, N2, F2,Cl2or their ions,most of the U and Th migrat directly or indirectly to the zone of enrichment (ZE) under the lithosphere first, and then to the crust. (2) In the rocks without volatiles or with volatiles having no oxidation ability, the U and Th will exist in metal or low valence compounds with high melting point and high density. In that case, the U and Th are stable and reluctant to migrat. So in the planets without volatiles in the interior near the Earth's core, the U and Th will sink down to their center. 2. The unique evolution history of the Earth is closely connected with the properties of U and Th mentioned above and its volatiles. Because of the participation of the volatiles in the migration of U and Th ,most of the U and Th in the interior of the Earth migrat to the ZE first,then they heat the rocks to melting . So the rocks in the ZE are plastic, which causes the mantle convection and the drift of continents. It is the U and Th enriched in the ZE that drive the global crust movements, especially the plate movements. Without volatiles with oxidation ability , there would be no ZE in the planet. Without the ZE, there would be no the plate tectonics in the Earth. In the Earth's core, these U and Th also can be driven to the ZE by the upward plumes when they are changed into high valence compounds and complexes in the core_mantle boundary by combining with H2O, O2, N2, F2, Cl2or their ions that come from the mantle,subduction plate and down plumes. In the other planets, because of the lack of volatiles with oxidation ability, there are no ZE like that in the Earth, and there are no the plate tectonics in their crusts either. Also because of the participation of the volatiles in the migration of U and Th in the early stage of the Earth, the contents of U and Th in the ZE reach their highest values, then decrease with time. Correspondingly the intensity of global crust movements decreases with time, which is advantageous to the evolution of living beings. But in the planets like the Mercury and Mars which have no volatiles or like the Venus which have only little volatiles with oxidation ability, most of U and Th will sink into their cores first, then they heat their cores to melting facies and the melting facies enlarge with time. At last, they may reach the position like the ZE in the Earth and then lead to the mantle convection and drive the global movements. So their evolution are slowed down because of the lack of volatiles. Or the heat in their center is sent to their surface only through intense volcanic activities as what occurs in the Mars. The intensity of the global geological activities in these planets increases with time, which is contrary to things in the Earth. 3.The migration of U and Th from the ZE to the Earth's surface varies with time. In the early stage, the increase of U and Th in the Earth's crust is very quick due to the intense volcanic activities, large dose X-ray from the U and Th can destroy the DNA of living beings and is dangerous to them and restrain the development and evolution of living beings. After the Phanerozoic eon, this kind of increase of U and Th is slowed by changing the migration way from intense volcanic activities to plate movements, the small dose X-ray can not destroy the DNA of the living beings, and is not harmful to life but may cause a small change in the gene structure of living beings and become a resource to lead to the diversity of living beings and the biological evolution.

Abstract:The surface characteristics of mineral fine powders will affect the reinforcement effect of mineral filler upon silicone rubber matrix, and the interfacial interaction between mineral filler and silicone rubber matrix will be the mechanical properties of silicone rubber filled with mineral fine powder. Using double liquid method the authors measured the equilibrium contact angles of the surface modified and surface_unmodified mineral fine powders of talc, quartz, granular wollastonite, fibrous wollastonite, kaolinite and ground CaCO3. According to Fowkes ' and Young's theory, the surface energy of the above mineral fine powders were calculated. The results show that surface energies, dispersion components and polar components are different for different mineral fine powders caused by differentce in composition, structure and surface group for different mineral powders. After surface modification of mineral powders, their surface energy will decrease, and the extent of decrease of surface energy will be affected by kinds and concentrations of coupling agents. Based on the surface energy, the interfacial tension (γSL) and the adhesive work (Wa) between mineral fillers and silicone rubber were calculated. Analyzing and comparing Wa,γSLand tension strength (σB) of mineral powder silicone rubber composite materials reveal that there exists positive correlation between (Wa/γSL) and (σB). In other words, the larger (Wa/γSL) the composite materials, the stronger the interfacial interaction between mineral fillers and silicone rubber matrix, the better the mechanical properties of composite materials. It is belived that the rule is suitable not only to unmodified and modified mineral powders in silicone rubber matrix but also to other rubber matrix. The paper has also made a deepgoing theoretical and experimantal analysis of this rule.

Abstract:The Honghuagou ore district and the Lianhuashan ore district in theHonghuagou gold orefield of Chifeng area, Inner Mongolia, have the same lead isotopic composition. The Mesozoic-Cenozoic magmatic and volcanic rocks exhibit very similar lead isotopic composition. The lead isotopic composition of Archaean gneiss and Proterozoic migmatitic granite is also close to that of the above rocks.206Pb/204Pb,207Pb/204Pb and208Pb/204Pb ratios of these rocks are 17.3— 18.1, 15.4—15.7 and 37.2—38.2 respectively; ore lead varies in a wide range, with 206Pb/204Pb,207Pb/204Pband208Pb/204Pbbeing15.37—16.49,14.66—15.89and 35.92—38.48, respectively. The isotopic composition of rock lead is obviously different from that of ore lead, and the arrangement trend of ore lead has nothing to do with the distribution of rock lead, suggesting that the material source of ore lead is not connected with these rocks.This is quite different from character of other gold deposits in the same ore zone. The lead isotopic composition of diopside_bearing plagioclase amphibolite is consistent with or close to that of ore lead, implying the probable existence of genetic connection between them. In the lead isotope evolutionary diagram, ore lead assumes linear arrengement, suggesting that it might be a mixture of two end members, i.e., a mixture of old basement rock lead and old multi-stage evolutionary lead. The end member of the low radiogenic lead reflects the contribution of the Archean basement rocks which are older than rocks of this area to ore_forming materials,whereas the end member of high radiogenic lead represents old multi-stage evolutionary lead,which is the evolutionary product in a highμand high W environment. The source rock of ore lead and gold might be mainly diopside-bearing plagioclase amphibolite within greenstone formation of Archaean besement. Being obviously different from lots of ore deposits in the same ore belt, the Honghuagou gold orefirld has its unique genetic character.

Abstract:Realgar is an important auriferous mineral in the Manaoke large_size ultrafine disseminated gold deposit. In this paper, the authors have studied mineralogy of realgar from the deposit,including its mode of occurrence, physical properties, chemical composition, X-ray diffraction features, cell parameters etc. The results show that the realgar is a low-temperature As-deficient variant (β-AsS) containing Sb, Fe, Hg, Au and Ag. Its unit cell parametersa09.357 (3),b013.581(4),c06.613(3)A;,β106°34′(2) and V0805.51(37)A3; are somewhat bigger than those of normal" realgar (β-AsS) from other areas. On such a basis, the modes of occurrence of Au and Sb in realgar crystals in relation to gold prospecting are tentatively discussed.