Abstract:In the territories of Jiangxi, Fujian and Zhejiang provinces there have widely developed a kind of particular medium-acidic ignsous rocks of mesozoic and caenozoic, with the features possessing in lava,volcanic arenite and subvolcamc rock. The main rocks from Xiangshan volcanic basin in Jiangxi are the most representative of the areas mentioned above. However, in regard to the problems of their nomenclature and genesis there is still existence of greater controversy. Owing to that these rocks are genetically related to the uranium deposits, they have received considerable attention from geologists in a long period of time. The results in studing inclusions of the main rocks from soven volcanic basins show that the glass inclusions are well developer in these rocks which display aneru- uotive feature.The temperatures for formation of the rocks are as high as 1200℃. According to the features of inclusions, the main rocks can be divided into Xiangshan type and Gaojia type. The study on inclusions also shows that the combination of high-saline fluid inclusions, the inclusions containing CO2 and boiling fluid inclusions may be served as an important information indicating the environment favorable for min}ralization of urapiupn deposits.
Abstract:Since last two decades, Geologists of each country have devoted much attention to and studied retrograde metamorphism all over the world, pub- lisped many articles continuously, and made a considerable headway. In the United States of America, for example, the retrogression of philadelphia area, pennsylvania has early been discussed; afterwards retrograde metamorphism for Broken Hill district, Australia; Saleix area (French pyrenees);Almklo- vdalen, and western coast, Norway; western Veporides in the Soviet Union; Hida area, central Japan and soforth have also been studied, publisb.ing con- tinuously works. Especially, retrograde metamorphism of Lewisian Complex, NW Scotland was investigated thoroughly. At present, retrograde study make progress in the following several aspects; (1) tectonization, rock deformation&retrograde metamorphism, (2) Causing retrograde metamorphism, following decreasing temperature, (3) retro- gressive geochemistry study, (4) retrograde metamorphism and minerogenesis, (5) Regional metamorphic thermal metamorphism. The prograde metamorphic study should not be overemphasized at the expense of the retrograde metamorphic. For highly raising the retrograde metamorphism level of our country in end of the century, I make some sug- gestions; 1 .Pay great attention to tectonization, and tectonic framework in the field, and try to fine which tectonization is related to the retrogression more seriously. Deformation domain is more usually a place retrogressive. Both sides of plate collision indicate a gradually retrogressive belt in an extensive region. These aspects at home have not yet been noticed. 2. The retrogressive reaction study must be strengthened, although started. When we make an experiment in the progressive reaction, retrogressive reac- tion test must be added to some extent. 3. Studies of the retrogressive geochemistry and fluids controlling retro- gressive activity law, following height of level in isotope assay and microarea measurement, should achieve good results. 4. Attach importance to ore deposit related to the retrograde metamor- phism, pay attention to the retrogressive shear zones controlling ore-bearing property and information of ore shoot near the ore body. 5. We not only study retrograde metamorphism of early precambrian but also look fixedly at that of proterozoic, Palaeozoic and mesozoic. We expect that in the year 2000, using new determinative techniques, deformational ret- rogression, retrogressive reaction, retrogressive geochemistry, retrogression & ore deposit, retrogressive thermodynamics, ect, should be modernized to create a branch of the metamorphic petrology-retrograde metamorphism.
Abstract:The infrared spectra of 27 biotite samples, collected from various granitic bodies of southeastern China including Nanling and middle and lower Yangtse Valley, were obtained on four different types of infrared spectrometers. The res- ults are well correlated. According to Fosters classification all the samples can be divided info two sexier-Mg-biotite and Fe2+ -biotite. The MFA values (Mg/ Mg+Fe23 +Fe3+ +Mn+ivAl) of the Mg-biotite range from 0.01 to 0.20, while those of the Fe2+ -biotite from 0.4 to 1.40. The shift of some characteristic ab- sorption bands in consequence of their chemical compositions is determined and discussed. The substitution of the major cations for each other is also discussed and referd to their crystal structure. The investigation shows that it is possible to indicate and estimate the ca- tion contents in the octahedral sites and the ratio of Al/ Si in the tetrahedral sites of biotite by means of the infrared spectrometry.
Abstract:Lueneburgite (Mg-P borate) was discovered in 1968 by the author, in spite of its rarity as from a mirabilite deposit in Shansi, China. Different methods of identifications have been performed on the mineral for its mineralogical aspects with such as microscopic and SEM determinations, and spectral, microscopic laser spectral, chemical, differential thermal and infrared spectral analyses. It is demonstrated that the Mg-P borate, formula Mg3B2O (OH)4 (PO4)2. 6H20, occurs as spherical aggregate and exhibits a diversity in morphology, with cell parameters a=9，710A，b= 7, 553A and c=9,922A，and β=97°06'. The strongest lines in the powder diffraction pattern are 5, 00 (10)，2,97(10)，4，87 (9)，2,83(9)，3,25(8)， 3,03(8) and1,943(7)，and the main infrared absorption bands, 3399，3232,1663， 1122, 1074 and 1019 cm-1.
Abstract:The photomultiplier-cell photomicrometer is an essential instrument in app- raising and analyzing mineral (especially for metal mineral). Up to the present, the best way to quantitate accurately various optical quality (including reflectivity, transmissivity, reflective transmission and apparent angle of rotation of heterogeneous substance, etc,)is the method of plzotomultiplier-cell. In 1978, adopted transistor circuit, the authors had assembled a complete mo- del of instrument connected with Orthaolux- Pol BIk microscope to constitute the photomultiplier-cell photomicsometer, which was made use of an illuminant vol- tage-stabilizer, direct current high-voltage stabilizex and photomultiplier-cell direct current operational amplifier. In 1981，a new design was found application. Inte;rated circuit and digital display had been put to use in the reformed instrument. So it is featured with less in measure limit (the inferior limit is 5 micron)，high precision (relative errox is measpre is below 2%)，little volum and easy to handle.
Abstract:Bentonite quality depends largely on its content of montmorillonite. Method of methylene blue adsoxption has been used usually to estimate the approximate montmorillonite content. But the peavey liquid separation method is considered to be the most precision process to separate the montmorillonite from other minerals. The specific gravity of alcoholic bromoform mixture, the speed and types of centrifugal equipment and other technical parameiers were studied in detail. An optimum testing procedure is described in this paper. More than 1O Chinese bentonites have been separated, and the contents of montmorillonite have been determined. A new coefficient of methylene blue adsorption for bentonite is found by comparing them with those of the methylene blue adsorption. It is considered in this paper, that this new method is important for examing the qualify of bentonite. Tlse above method is technically practical not only for fon- dry industry but also for geologic examination.
Abstract:This study deals with the use of plasma direct reader for simultaneous mul- tielement analysis of pyrite minerals. 100mg of sample was dissolved in nitric acid and filtered. 11 trace elements iron (mostly are volatile) in the filtrate, which were suffered from iron interference were determined after passing thro- ugh cation exchange column. Filtered residue was attacked by either method depending on demands. (1) HN03+HCl ( 3+1) was used for pure pyrite and (2) alkali fusion was used when total contents of aluminum, titanium and tin were required. The resulting solution was combined with the eluted solution of some other 17 elements retained on the column and then analyzed in a separate pro- cedure.
Abstract:Beryllium forms a red violet 1:1 complex with khimduchlo rophosphonazo-I rapidly in the presence of hexamethylene-tetramine buffer (pH 5)，which exhi- bits maximum absorbance at 590 nm (molar absorptivity=9.44× 103 L.mol-1· cm-1).Beer's law is obeyed for solution containing 0-25 µg of beryllium in 25m1 of solution. Interfering ions can be masked by the addition of small amounts of EDTA.
Abstract:A method for determining major and trace elements (Na, Mg, Al, Si, P, K, Ca, Fe, Ti, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Mo, Sn, Ba, La, Y, W, Pb, As, Th, U) was decribed. Pellets are prepared by pressing the sample powder and matrix effects are corrected by experiencecoefficient method. The accuracy and precision of results were satisfactory. The method has been applied to the ana- lysis of different kinds of samples.
Abstract:A new extraction chromatographic technique for rapid separation of Ga in rocks using dimethylheptyl methylphosphonate (P350) as stationary phase and polydivinylbenzene (x-5) resin as supporter has been studied. The sample solution in 2.0 N HCL-3.4 N NaCl medium was introduced on the chromatographic column,Ga can be eluted quantitatively by water.The percentage recovery of Ga was 99.5-100.1%·This method is applicable to determination of O.OOOOx-0.Ox0o gallium in rocks.
Abstract:Optimum conditions for the determination of Ge by graphite furnace AAS were studied. The effects of some metal salts on the determination of Ge were tested, the bulk of sulphate ions derived from the sample was eliminated by means of barium chloride. GeCl4, was extracted with benzene and back extracted with water. Sensitivity for Ge was increased by about 100 times using Ni-(NH4)2 -C2O4-NH40H as mixed matrix modifier. The absolute sensitivity of Ge was 8.8 x 10-12g. The RSD for sample conta- ining 0.94ppm of Ge was 3.9%(n=11).
Abstract:The behaviour of 8 noble metals (Au,Ag，Pt, Pd, Rh, Ir, Os, Ru) on graphite furnace HGA-500 was studied. The advantages of both ommon raphite tube (GT) and charring graphite tube (PGT) were compared. Optimium onditions were established for the determination of 8 noble metals and their snsitivities listed.
Abstract:A differential puts ancxlic stripping peak of indium appeared at -0.52v (Vs Ag/AgCl) in a solution of 1.65N KBr -0. 05N HCL -0.02% NH2OH . HCL. Under this condition, In can be determination within the range 0.0004一O.O2µgml-1. The detection limit was 0.04 ppb. The presence of 30-fold excess of Cd and 100 -fold excess of Pd only causes negligible interference. The interference caused by other ions is prevented by the preliminary chromatographic separation.
Abstract:The 7502 ICP Direct Reader was recently manufactured by Beijing Second Optic Instruments ractory. A trial of this instrument was made in the analysis of geological samples, 24 major, minor and trace elements were determined simul- taneously. Both linear and nonlinear interference corrections could be made by maans of a computer to correct the interelement line and background interfere- nces. The performances of this sophisticated instrument appeared to be good and both detection limits and precisions are close to or occasionally better than si- milar foreign instruments.
