Abstract:Nearly all geothermometer are thermometer of magmatic or metamorphic processes. Rhombic section. angle thermometer can determine the temperature of deformation, so it can be served as a deformation thermometer. Pericline twinning, whose composition plane is rhombic section，is formed mainly ,by mechanical deformation. The position of rhombic section varies with both chemical composition and structural state of plagioclase, which itself is a function of temperature. Consequently the position of rhombic section is depe- ndent on the temperature of deformation, during which Pericline twinning Was formed. In Ekou granite body of Wutaishan area 49 angles of rhombic section and corresponding compositions of plagioclase have been determined and 49 tempe- rature values have been yielded. On histogram (Fig. 4) there are two tempera- tune peaks 520℃ and 480℃, which are similar to 494-508℃ inferxed from garnet-biotite pair of country rocks. It means that temperature of deformation is in agreement with temperature of greenschist metamorphism. In Wutaishan area durimg greenschist grade metamorphism two epizodes of deformation have been olisaived, which -coincides with the two temperature peaks: Therefore rho- mbic. erection angle thermometer provides , a means for study the relation, petyy- een deforrciation and metamorphism.

Abstract:Four. chondrites fell in the Ningqiang county,Shanxi province (i. e.Long- titude 105º54 E, Latitude 32º55´N) at 7:00 P.M.of 25 June 1983. About 46068 specimens have been collected. The exterior ofchondrite is a layer of fusion crust, approxrmazery 0.7-1 mm thick. In the interior of chondrite, white gray chondrules and aggregate irregularly disperse through the black matrix, and light yellow troilite and silver gray Awaruite and iron-nickel liamalite are observed. The morphologies of chondrite are circular, elliptic and irregular. According to the crystalline degree, they are glassy, cryptocrystalline, microcrystalline and various porphyritic, grained chondiite texture. The forms of aggregate are more complex. But, they are largely elliptical, irregular and myrmekitic texture. There are more than 30 types in Mineral . compositions.. Transparent miner- als have been found as follows: eorsterite, chrysolite, enstatite, augite, gehlenite, akermanite,spinel, apatite,monetite, .calcite, dolomite, quartz, bytownite and albite. Opaque minerals have been found as follows: troilite, iron-nickel kamalite, pentlandite, magnetite, awaruite, chromite, and uncrystallized carbon. Chemical composition(%): SiO2 33.95 Al2O3 2.74 TiO2 0.134 CaO 2.25 MgO 24.5 NaO 0.55 MnO 0.20 P2O5 0.25 Cr2O3 0.53 Ni 0.95 Co 0.070 Cu 0.032 Zn 0.010 C 0.401 NiS 0.94 (total 99.718) Main chemical parameters; Fe/SiO2 0.72 SiO2/MgO 1.39 The above characteristics show that these chondrites should belong to C3 typc.

Abstract:Granite-greenstone terrain in the Dongwufenzi area had undergone threedifferent types of metamorphism. The ductile shear zones not only controlledthe distribution of different metamorphic rock associations, but also resulted inreversed series of regional metamorphic grades. According to the contents ofporphyroclast in rock, the ductile shear metamorphic rocks can be divided intothree groups: mylonitization rock, mylonite and mylonite schist. All of the three group rocks have mylonite texture and deformationtextures can be divided into single mineral type and associated type. A ductileshear metamorphic rock consists of minerals being inuni Variant equilibrium.According to the rock association, characteristic of mylonite texture and recry-stallization in rocks, two different ductile shear metamorphic zones have beenrecognized: Ductile-Brittle type and Brittle-Ductile type, They formed at the different depth of the earth crust and conditions of temperature and pressuredetermined by calculations of coexisting mineral pairs. The results obtainedshow that the gold mineralization, transportion and deposition are related tothe ductile shear metamorphic zones closely.

Abstract:In the Xianghualing district, Hunan, along the contact zone of the Yensh- anian ,granite and dolomite occurs a set of metasomatic complexes which belong to the rnagnesioslcarn (orrlation and constitute the Sn, W, Be, Pb and Zn ore-bearing rocks. The granite contains 568 pprn of ΣREE and has the Lower LREE/HREE (l .23) and δEu(0.47).The chondrite-normalized REE pattern of the granite reflects the feature of tlne Sn-and W-bearing granite. The REE patterns of the metasornatic cofnplexes are similar to that of the granite and are different from that of the dolomite, indicating that the metasoaiatic fluid is mainly derived from the granite nuagma. During the greisenization of granite, a large amount of REE was leached and entered the fluids. When these fluids entered the country rocks and they interacted to form Ca-Mg-metasomatites, REE precipitated. As a result, REE of ore-bearing metasomatic complexes in the outer contact zone decreased rapidly (REE=3-7 ppm)，reflecting that the wsvter/rock value increased and meteoric .water was added into the ore-forming fluid. This result also suggests that the migration capacity of REE is limited in the hot fluid, i. e. REE considerably precipitated near the contact zone, the precipitation of HREE orly occurred far from .the contact zone and the mig- ration capacity of HREE was stronger than that of LREE. The L1iEE/IIREE and δEu of each metasomatic zone rocks change regu- larly, which indicates that the constituent concentrations, temperatures, press- uses, acidites and oxydation-reduction potentials of floe fluid phase change systimatically.

Abstract:The alkali-feldspar phenocrysts in the two contrast Mesozoic granitic rock series, binary mica-adamellite---granite series(S-type)and diorite---porphyritic granodiorite---porphyritic granite series (I-type), of the area are very similar in many aspects. The phenocrysts are of large size, euhedral shape, and carlsbad twin. The plagioclase and biotite inclusions in phenocrysts aligne paralleled with growth face of phenocrysts. Generally, the cores of phenocrysts are rich in plagi- oclase inclusions, but .the quartz inclusions only occurred in tlae rim.The Ab, An, Ba contents in phenocrysts are higher than in groudmass alkalifeldspars. The forming temperature of the phenocrysts calculated from two一feldspar geothermo- meter of Whithey and Stormer (1977) are round 7000C; the X-rays reflections show that most phenocrysts are intermediate orthoclase, the other a few are orthoclase and microcline. All the features above convince that the phenocrysts are crystalized from magma.. Based on experimental data, the work also discu- ssed the crystalizinU processes of the phenocrysts and it is considered that cry- stalized alkali-feldspar phenocrysts represent high vyater content of granitic magma.

Abstract:The Lingshan granite body is a composite intrusive body (Fig. 1) consis- ting of coarse porphyritic hornblende=biotite granite (γ2-2(a)5)，medium-coarse grained biotite granite(γ2-2(b)5)，medium-grained albitized protolithionite grani- te (γA1) and albitized zinnwaldite granite (γAII) formed from early to late in the sequence of γ2-2(a)5→γ2-2(b)5→γA1→γAII The petrochemical compositions, ratios of characteristic elements and ages of these granites suggest that there exists a relationship between these granites. Data of optical properties, chemical compositions (Table 1 and 3) and X- ray diffraction (Table 2) of the feldspars have been presented respectively in the papery forms and structures of the feldspars have also been studied with the aid of microscope (Photos 1-6).The results indicate that there does exist a relationship of differentiation evolution between these granites. The feldspars from the γA1 and γAIIa show many clear metasomatic alteration features; the- refore, the authors genetically consider the albitized protolithionite granite and the albitized zinnwaldite granite to be metasomatic altered granites. It may also be suggested that a rare element-bearing granite was formed as a result of magmatic differentiation and postma}matic metasomatism.

Abstract:Zircons from Mesozoic granites of this area are rich in ΣREE, Mo,‘ poor in Zr/Hf, and deficient in Zr. With the evolution of magma and the develop- ment of the rock body from early intrusive stage to late stage, the zircons show obvious regularity of gradual increase in Hf, ΣREE, U and decrease in Zr/Hf. Zircons of different generations have remarkably different contents of trace elements, with those of late generations being richer in metallogenic ele- ment (Mo)，rare earth elements and radioactive elements. The study of trace elements in zircons may provide information for ore potentiality of. intrusive bodies. The relative increase in Hf, ΣREE, Th, U might be regarded as an important indicator for potential Mo mineralization of the rock}body. Such mineralogical-geochemical information as Zr/Hf=24.1 and Th/U=5.2 for zircons from Mesozoic granites lays the foundation for the gene- tic classification of granites in the area and the determination of genetic ty- pes for syntectic granites.

Abstract:The Arskartor beryl deposit is made up of fine albitized muscovite granite (γ(1-1)5，γ(1-2)5)，pegmatite and beryl ore zone. The muscovite granite is a cupola. dipping outward. The pegmatite is of the simple type which can be divided from outer part to inner into pegnlatitic altered granite, altered pegmatite and quartz core. The beryl ore zone, characterized by comb, brecciated and banded structures as well as pegmatitic thetexture, lies in a periclinal structure on the northeast of the cupola, and is controlled by a tension-torsion fault. Following are some mineralogical characteristics of the beryls and the aquamarines; Chemical analyses indicate that the colour and the relatively good trans- parency of the azure and dark blue beryls are related to the fairly low con- tent of alkali metals in the Be clusters, and that the azure beryl is high in Cr, Sr, Pb and Zn, while the darlc blue beryl has high V and somewhat higher Cr and Rb. Temperature measurements of inclusions , in beryls suggest that the deposit belongs to pegmatitic-pneumatolytic-hypothermal-mesothermal type (the aquamarines formed at high-medium temperatures)，with the formation pressure being 650士50 atm. The aquamarines contain water molecules in their textural pores, and have hardness of 7.7, refraction indexes Nc=1.57A3, No= 1.5788 and specific gravity 2.73.

Abstract:Stanniferous native copper was discovered in 1983 in some oxidized ores ofthe Maotang gold field in Xichuan, Henan Province. It occurs in brecciated gold.-bearing granite porphyry as fine-grained aggregates 0.06--0. 15mm in size withkaolinite, limonite and native chromium as associated minerals and feldspar,quartz, pyrite and native gold as accompanying minerals. It is bronze in colorand metallic in Iustre. It has microhardness of 184--189kg/mm_2 and specificgravity 9.04 (calc.). Under reflected light, it assumes reddish yellow colour,reflectance values being 33.43 (470nm), 46.78 (546nm), 58.77 (589nm) and 65.21(650nm). T The stronger lines in X-ray diffraction are 2.1608 (10), 1.8235 (7), 1.2932(5) and 1.1022 (5), showing this mineral to be isometric with space group O-h5-Fm3m and unit cell a0=3.655 A and Z=4. The chemical composition as determined by electron microprobe analysis is 93.38% Cu and 9.38% Sn, giving a chemical formula of Cu18Sn. Stanniferous native copper, equal to a-phase of Cu-Sn alloy, is discoveredfor the first time in nature.

Abstract:Emplaced in gneiss of Taishan Group, the Zaozhuang subalkalic complexhas an isotopic age of 101--133Ma. The present paper deals Inainly with the relationship between typomorphiccharacteristics of apatite and its origin, makes an examination on such experi-mental data of. apatite as REE distribution, X-ray diffraction, crystal unitparameters and infrared spectra, and conducts a tentative investigation into theformation temperature of apatite, the concentration of P2O5, the physical-che-mical condition for ore formation and the genetic type of apatite deposit.

Abstract:NordenskiSldine, a rare nesoborate mineral, was found in a fluorite deposit in Wuxian county, Jiangsu province in 1983. Its optical and physical properties are as follows: uniaxial negative with No=1.774(±0.0015) and Ne=1.661(±0.0015);gravity 4.09; distinct(0001) cleavage; colour milky white but greyish white in the thin section. Its composition is determined as SnO2 51.26%，Ca0 20.48%，B2O5 25.0%， Fe0 0.4%，MgO 0.14%，SiO2 0.39% and TiO2 0.14%，giving a chemical formula of (Ca1.02Mg0.011El0.017Ba0.002)1.050Sn0.96(BO3)2. Being a skarn minexal, it occurs at the contact zone between the granite intrusive body and the marble. The discovery of such a rare mineral not only r eveals new occurrence of this mineral, but also casts some new light on the geochemistry of Sn and B.

Abstract:The ore deposit is a hypothermal-mesothermal cassiterite sulphide one.It has been revealed through the author's investigation that with the decreasein ore-forming temperature the mineralization stages varied from cassiterite-quartz through cassiterite-sulphides to cassiterite-calcite, and cassiterite sho-wed tendency of growth both in lengths of unit cell axes, especially axis C,and in unit cell dimensions. There exist such admixture elements as Fe in cassiterite which can subs-titute isomorphously for tin. As ionic radii of these elements are usually small,the isomorphism might cause unit cell to shrink. At high temperature, isomor-phous substitution of elements takes Place rather readily, and this probablyaccounts for small unit cell of cassiterite at high temperature and larger oneat low temperature.

Abstract:After first' report of rli.s^oveiin} pseudomorphous oetahedra of serpentine in 1981 pseudomor-phous octahedra of chrom-barring chlorite also has been diseovered in chromite of the same ultra-mafic rocks.Chlorite is the substitution product of serpentine.Basad on reseaeh rosults we can make following conautionse 1. the piim}ry mineral of oetahedral pseudomorphous chlorite must be γ-olivine. The pressure of formation of γ-olivine was about 140kb, corresponds to 500km in depth;2. Al, Cr of pseudomorphous ocLrherlra must come from chiomite} 3. Chromite including pseudomo-rphous octahedra of serpentine and chlorite, may be a type of directly coming from lower part. of mantle; 4. North Tibet ultramafic rock belt would be formed deeper than that in South Tibet belt, because pseudomoiphous octahedra are found only in North Tibet ultramafic rock belt.