Abstract:Okinawa Trough is tectonically a back-arc basin of a trercharc-basic. sys- tem. The unceasing extension of the basin has caused intensive and repeated vol- caztic activities in the bottom of the trough. During the volcanic activi+ies of the latest stage large amounts of intermediate or acid pumice were formed., which constitute the main submarine rocks emerged from the bottom of the 1rough. The pumice in Okinawa Trough is distrzbuted in a NE-SW direction and in an intermittent linear way, which is closely related with the submarine mountains, The pumice encountered on the bottom of the through represents the cognate and isogenetic volcanic eruptive material, i. e.，the liparite-pumice that is intermediate and acid yet meta-acid in acidity and belongs under the calc-alkaline series,The submarine eruption is of effusivetype. The pumice is with typical pumrceous structure and porphyritic texture, The pher,ocryst is usually high,-temperature andesine or hypersthene and occasionally quartz. It is character istic of the phenocryst containing relatively more vitric as well as monocyclic and binary enclosures of vitric and gas, The ground mass is acid volcanic glass (N=1.496-1.500).There is a lot of CO2 in the bubbles, The temperature for crystallization of the phenocryst of high-tempera+ure andesire is 1050-1100℃. The pumice contains fine debris enclosures of basalt and andesite, ia:dicating it represents the eruptive material following basal1 and andesite, Judged from the rocks,the pumice falls in the followitug rock assemblages tholeiite, andesite-, liparite-andesite-pumice and liparihe-pumice. The age of the pumice determined by the method of thermoluminescence is 35400-37100yers, which shows the pumice was formed in the late pleistocene. The pu-mice is arc-volcanic rock.

Abstract:The studied domain is located to the north of the North China and the Tarimalxa metamorphic domains, including most part of the Mongolia. As a Palaeozoic inter eontinental geosyncline, it is situated between the Siberia and the Tarim-Sinokorean massifs. The domain was subjected to the Arch.can and the Early Proterozoic regional dynamic heat flow metamorphism and Late Proterozoic regional low-temperature dynamic metamorphism successively during the P resirian period. It became a stable massif and probably combined with the south and the north massifs in the Late Proterozoic (about 800Ma). The dismembering and riftting of tire domain began in the Sinian period so pares of the domain was transformed from a stable massif into a moble geosyncline. From Sinian. to Cambrian, most part of the domain might be the stable upwarded district, only in tire north and the south, margins of the domain the Caledonia geosynclines was formed, then the domain began to converted into a mobile sea trench in a large area during the Ordovieian. It was subjected to regional low-temperature dynamic metamorphism or regional dynamic heat flow metamorphism during the period from Cambrian to the end of the Silurian period. The metamorphic types appear in greater differences in different places, including regional dynamic heat flow, regional low-temperature dynamic or buried metamorphism. The domain was transformed finally into stable massif and combined with the south and north massifs again due to the Variscan metamorphism during the Devonian-Late Permian.

Abstract:The Proterozoic Haizhou group can be divided into low Proterozoic Jinping and middle-upper Proterozoic Yuntai subgroups, The Jinping subgroup belongs to the metamorphic apatitolite-schist formation and the non-metamorphic apa- tite-bearing dolomitic carbonate-argillo-arenaceous sedimentary and the Yuntai subgroup-metamorphic leptynite formation and nonmetamorphic interme- diate acidic volcanic-elastic formation, The metamorphic formations can be divided into high greenschist facies consiting of albite-amphibole zone and low gzeenschist facies including the albite-actinolite zone, Having study of the metamorphic minerals and their deformations the authors suggest that the Haizhou group be- longs to the high-pressure metamorphic series of regional dynamometamorphism.

Abstract:In the Northeastern Jiargxi whexe ophiolite develops occur high temperature metamorphic rocks including various hornstones, diopsidite and melilite marble and high pressure metamorphic rocks, such as aragonite-jideite bIueschist, lowsonite schistose marble and piemontite-chloritoid schist, Both kinds of these metamorphic rocks are emerged only within the Proterozoic formation and associated in space with the ophiolite. There are indicatiors that a magmatism-thermometamorphic mechanism is occured during the developmen+. of the continent margin ophiolite. From mention above and the fact that the high pressure metamorphism is supe- rimposed on the high temperature metamorphic rocks, the authors suggest that the high temperature metamorphism is related with the madrnatism in the early stage of extension of the ocean basin where the ophiolite development, and the high pressure metamorphism is occured in the tectonism in the late stage compre- ssion of the ocean basin. This mechanism is called by us as"superimposition mOrphlSm"which is differenr: from the paired metamorphism.

Abstract:The Zhongtiaoshan area is one of the famous concentration areas of copper deposits in China. A large quantity of tourmaline has been found in the hydro- thermal-sedi-lnelrtary formation which hosts Hu-Bi type stratabound copper de- posits, the calcalkaline subvolcanic-volcanic sedimentary rocks which host the To- ngkuangyu type copper deposits, and other geological environments of this area. The content of tourmaline can be more than 50% in tourmalinite, but varies in the range of 5-40% in other rocks. Due to the difference of formfug conditions and manners in different geological envirollments, tourmalines show obviously different optical properties and typomorphic characteristics. All tourmalines are dravite-schorl series and contain virtually no lithium.They were formed as a result of hydrothermal deposition in submarine basin, through volcan ic hydrothermal exhalation and hydrothermal metasomatism which, however, were all related to magmatic activities in the Zhongtiaoshan area in 2100 Ma age or so,

Abstract:The Hongshiquan uranium deposit is a new type uranium deposit recently discovered in China, The host rock-pegmatitic alaskite intruded into metamorphic rocks of the Lower proterozoic Longshoushan Group.The deposit is a polygenetic one formed as a result of composite metallization of magmatic pneu-mato- hydrothermal solution and late ore-bearing hydrothermal solution with the former playing the leading role. From the relationship between the activity of biotite in the magma and the crystallization temperature (T),i.e., Lna it is considered that the phenomehon that the biotite along the margin of pegamatitic alaskite crystallized obviously later than such rock-forming minerals as feldspar and quaT-tz is attributed to the comparatively small activity of biotite in the alaskitic magma which resulted in the decrease in its crystalliz}taon tempe- ra1ure until its crvstalliza1ion in the maamatic nneumatolvto-hvdrothermal stage. The synchronous ernichment of biotite and uraninit is a geological activity with crystallization differentiation of magma,element geochemistry and thermodynamic effects being dominant.According to thermodynamic principles and statistics, the authors consider the reasons for the intimate relationship between hiotite and uranirite to be as follows;(1)their close crystallization time,(2) the existence of certain genetic relationship and(3 ) the apparent affinity of hiotite and urauirite in composition, The syxtchronous enrichment of binti1e and uraxeinite depended on composition and physical-chemical conditions of the magma. It is therefore concluded that the biotite concentration zones aloaig the margin of the pegmatitic alaskike are favorable oro-prospecting places.

Abstract:A trioctahedral chlorite/saponite ( 1:1) regularly interstratified clay mineral (C/Sap) is found in Lichuan area, Ensbi county, Hubei province. Occurring in calcic-sandy clay rocks and sandy petite of Triassic Badong Group, it has irregutar scaled, shape, with G=2.75, H=1-2, and n=1.558-1.572.Detailed chemical analysis, X-ray diffraction, infrared absorption, thermal analysis and electron microscopy all indicate that this mineral is made up of altexinate trioctahedral chlorite and trioctahedral saponite layers, haviltg d 060=1.531A，b0=9.19A，and cosinβ=29.05A.A good integral sequence of 001 diffraction obtained for the air dry sample suggests a regular intetstratification, with δ=0.1007,υc== 0.347。 The chemical structural formula is(Mgo.26Cao.18 K0.09 Na0.03 H0.10)0.66(Mg6.32Al1.56Fe3+0.48Fe2+0.15)8.51(Si6.47Al1.56)8O20(OH)10nH2O. C/Sap of Lichuan resemble correrisite in IR spectra, Its wave numbers of abs- onion are 3670, 3556, 3415, 1630, 1080, 1002, 953, 898, 665, 650, 520, 460 and 445 cm-1.On DTA curve there are four endothermic effects(118℃，235℃,600℃,820℃) and one exothermic effects (852℃) The total weight loss of C/Sap is 15.9%,of which dehydroxylation weinht loss is 8.37%.

Abstract:Chromian goldmarite is discovered in marble along exocontact zone of the Tongshan copper-molybdenum deposit, Jurorg county, Jiangsu province, It is of isometric system, with space group Oh(10)-Ia3d, unit cell parameters ao=11.9470A Z=8; is chemical composition is Si02=34.99%，A1203=7.61%，Ca0=32.95%， V205=13.41%，Cr2Og=10.13%，giving a chemical composition of(Ca2.938Na0.003)2.941 (Cr0.666V0.737Fe0.006Al0.591)2.00(Si2.938A10.156)3.094O12 Refractive index n=1.799 (士0.0015).Calculated specific gravity3.75, VHN100=1168.7kg/mm2, Moss hard- ness 7.1.It is a mineral formed as a result of syngenetic deposition and intrusive contact metamorphism and contining vanadium, chromium and aluminium. The discovery of this mineral has added a new member to the garnet group and also provided new data of occurrence for chromian-varadic minerals In addition, it is of great sigrificance to the study of chromium-vanadium geochemistry.

Abstract:The crystal structure of anorthoclase was determined by the single-crystal method quite a few years ago. In this paper, the intensities of reflection were collected with X-ray powder diffractometer, and 474 independent diffractidn data were involved in the calculation, with the final discrepancy factor R=0.114.The ideal formula for the anorthoclase is (Na, K)A1Si308. It is of triclinic system, with the lattice parameters being a=8.267士0.0025A，b=12.954士0.0017A， c= 7.149土0.001A，a=92º12.2'士1.8',β=116º020.4'士1.2', γ = 90º12.1'士1', V=685.4A3， Z=4. A comparison between the result obtained by powder method and that by single-crystel method shows that they are in good agreement with each other and that the band distance and bond angles are on the whole reasonable. Nevertheless, the accuracy of determination requires further improvement.

Abstract:With the aid of automatic direct method and Fourier synthesis, the author has determined the crystal structure of gorgeyite from Triassic evaporates in Sichuan. province. The structure parameter corrected by least squares method is R=0.084. structural analysis shows that gorgeyite is of monoclinic system, with space group C2/c,a=17.462(8)A,b=6.828(2)A,c=18.219(9)A，β=113.45(4)º,V=1992(1)A3. Z=4,，Dm=2.91 and Dx=2.90(3).The mean. lengths of S-O bonds of three sulfate tetrahedra are respectively 1.467, 1.464 and 1.478A.There exist three sets of calcium atoms, which have six-fold coordination with the mean. lengths of Ca-O boxids being respectively 2.516, 2.515 and 2.459A.Amdng these atoms, Ca1 lies alonrg the diced axis. The potassium atom has eight-fold coordination. The hydro- gen atom in the mineral has been located for the first time, and it is proved that the mineral contains one molecule of crystalline water rather than 1.5 molecules. Its crystal chemical formula should therefore be K2Ca5(SO4)6H2O.