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摘要:Xiangshan caldera is located in the northwest of South China, Caledonian folded belt, which is elliptical and occurs on the basement of Sinian meta- morphic rocks. Because the violent volcanic activities in the Late Jurassic, especially the huge volume extrusion at higher speed in the late stage, the collapse arose when the transitional magma chamber was emptied. Subvolcanic coatis intruded along the collapsed ring faults. The volcanic complex is mainly composed of fragmentizing phenocrystic rhyolites. The volcanic activities began with the acid, with the highest in acidity in the middle-late stage and terminated with the marked decrease in acidity and alkalinity. The volcanic complex is principally composed of the acid vol- caaic and subvolcanic rocks. The potassium content is poor in them. The vol- panic complex belongs to calc-alkali, high-alumina, basalt series. The homogenization temperatures of glass inclusions in the phenocrysts of the volcanic rocks are equal to or above 1200℃.1t indicates that the magma was formed at higher temperature and at greater depth. The initial Sre87/Sr86 ratio of the volcanic complex is 0.7117士0.0009，reflecting the magma was the products that remelted in 'the middle and lower part of the sial and more mantle materials were mixed into the magma. Host rocks of uranium mineralization are rhyolite-dacite, fragmentizing phenocrystic rhyolite and subgranitic porphyry. The uranium abundances of various rocks in the volcanic complex are markedly less than that of granitic bodies in Southeastern China. 90 per cent of the uranium contains in the matrix according to the studies of uranium distribution. The uraninite is not preseat in the volcanic and subvolcanic rocks. The Sre87/Sr86 ratio of apatites associated with uranium minerals is very approximate to the initial Sre87/Sr86 ratio of the volcanic complex. It indicates that the source of uranium is derived from the depth.

摘要:There are two main types of skarn in the Makeng and Yangshan skarn iron ore deposits, 1 .Calcic-skarn of early stage. It consists manly of granets (grossularite-andradite series)，pyroxenes (diopside-salite-hedenbergite series)， vesuvianites, epidotes-clinozoisites, plagioclases and orthoclases, in the exoskarn it is usually accompanied by magnetitization, while in the endoskarn, molybde- nitization, 2. Manganese calcic-skarn of later stage. It is composed chiefly of Mn-hedenbergites, bustamites, pyroxmangites, Mn-ilvaites, Mn-wollastonites, which are associated with mineralizations of sphalerites, galenas and pyrites. These two types of skarn are closely related to each other but show dist- inct zoning either in small metasomatic column or in the whole deposit. They are both the products of the metasomatic action of a unified process of the skarn mineralization and may make up a new minerogenetic series of skarn mineral deposits. In this paper eight examples of various kinds of skarn metasomatic columns with corresponding mineralization zoning are given in detail. The data of belance compute of petrological chemical analysis of skarn zones for the main metasomatic columns suggests the migration law of major chemical ele- ments in the skarn metasomatic process, the skarn components like alumium, silicon and calcium as well as part of iron and magnesium are mainly. from the primary country rocks. But the most part of iron and manganese are car- tied up by hydrothermal solutions. The infiltration metasomatism of the che- mical components between aluminosilicats (diabasic diorites, granites and other elastic rocks) and carbonate rocks play the major role in the formation of the skarns, while the diffusion metasomatism also makes important contribution. Detailed investigation of the paragensis of the skarn minerals, especially that of the couples of pyroxene-garnet minerals indicates that calcic skarn and its associated magnetitizations are formed in the condition of lower acidity of the solution with higher oxygen fugacity. Along with the evolution of the sk- arns，the acidity of solution increaces and the manganese skarn, which is acco- mpaied by polymetallic sulfide mineralizations, gradually takes the place of the calcic skara.

摘要:Mossbauer spectrum of natural bafertisite from Jiangsu, China, has been obtained for the first time. The valence states, site populations, coordinations, isomorphous substitution and chemical bond of the iron in the mineral have been studied. The data were fitted successfully with a Least-square fitting com- puter program. The MlSssbauer spectrum consists of two non-symmetrical doublets. Their Mossbauer parameters are the following (at 298 K), for the outer doublet, I. S.=1。12mm/s, Q. S.=2.34mm/s, for the inner doublet, I. S.=1.13mm/s, Q. S.=1.89mm/s. I. S. is relative to a-Fe. Some informations about bafertisite have been obtained with the aid of MBssbauer spectroscopy, (1) No Fe3+ component spectrum was separated. The iron ions in the mineral are basically divalent, and it is consistent with the results of the chemical analysis.(2)Comparing the I. S. values of the mineral and other relative minerals, we obtained that Fe2+ of the mineral is in high spin state, its coordination number is six, and the chemical bond between iron and oxygen is basically ionic bond.(3)The two structure sites(M, andM2) of Fe2+ in bafertisite were justified. It is consistent with the crystal structure which was determined by peng Zhizong et al. The principal factor which in- fluences the Q. S. values is the arrangement of the coordination anions. For M1 site, there are two OH- (or F-)which occupy the opposite positions of the coordination octahedron. However, for M2 site, there is only one OH' (orF-) at the apexes of the octahedron, and its distribution is not symmetrical. The Q. S. value for M2 should be larger than that for M1. So the outer doublet was assigned to the Fe2+ in M2 site, and the inner doublet to the Fe2+ in M1 site.(4)The site populations of Fe2+ in M, and M2 were given by combined chemical analysis and Mossbauer spectroscopy. The results indicate that the distribution of Fee' in bafertisite is ordered, Fe2+ occupies mainly M1 site, and Mn2+ is preferable to occupy M2 site than Fe2+·There is isomorphous substitution between Mn2+ and Fe2+ at Mz site.

摘要:In this paper the occurrence and some characteristics of 6H-nigerite dis- covered for the first time in south China is reported, which was found in dolo- mitic marble in contact with Mesozoic granite, Associated minerals are, nanlin- Bite, taaffeite, chrysoberyl, phlogopite, nocerite, nobergite, spinet group etc.， This mineral occurs as a short hexgonal prismatic crystals, Which is different from that of 3H polytype. The cell parameters were determined by using X-ray single crystal method as a=5.71A，c=27.72A.There is an obvious difference between that 6H and 3H on X-ray powder diffraction pattern. Microprobe analyses of the 6H nigerite were calculated by a general formula, R2+(2-2x)R8+(4)O4, Where R2+=Zn, Fe, Mg and Mn, R3+=Al, he, x≌0.5.Thus, the cryst alochemical formula was written as R2+(6)Sn3R8+(24)O48. The genesis of this mineral was discussed.

摘要:A late hydrothermal lens have been found by the authors in the serpenti- mite at Guanyuan-Bao arer, Asbestos County Sichuan Province. In the lens two types of regulaly interstratified septechlorite-swelling chlorite (Se-Cg) and chlorite-antigorite (C-An) have been identified. Both the Se-Cg and the C-An have a evident sharp reflection at about 32A in the X-ray diffraction patterns. Behaviours and position of the d(001), d(002) reflection of both the regularly interstratifies minerals at 300 ℃，400℃，540℃，600℃ and 700℃ were analyzed and discussed in this paper. Properties of associated minerals; leuchtanbergite and septechlorite were reported in this paper, too.

摘要:This article deals with the occurrence, mineral assemblages, physical and chemical properties of magnetite in eastern Guangdong. The study shows that different occurrences and assemblages of magnetite correspond to different geneses. Mineralogical evidences suggest that the physical properties of magne- tite are related with the FeO, MgO, Mn0 contents, i. e.，along with the in- crease of the contents of these constituents there are decreases of gravity (5 .17 →4.79)，indentation hardness (725→551Kg/mm2) and increase in unit cell cons- tants(8.392→8.477A)of the magnetites. The variations of those properties of magnetite are closely connected with their geneses. In paragenesis of minor elements of magnetite, there are high percentages of Ti, Cr, Ni, Co and V, Ti: V=10:1, Co:Ni=1:1 in magnetite from post}magmatic differentiation iron depositsf high percentages of Mn, Mg, Zn and Sn, Ti: V=50:1, Co:Ni=2:1-3:1 in magnetite from contact-metasomatic iron deposits; high in Ge content, Ti:V =20:1,Co:Ni=3:1 in magnetite of volcano-sedimentary iron deposits; and great amount of Mn, Mg, Sn and Ge, Ti:V=26:1，Co:Ni=1:6 in magnetite from metamorphic iron deposits. Typochemical characteristic. of magnetite of diffe- rent geneses are quite clear.

摘要:Thorium-bearing pitchblende (U4+(0.68)U6+(0.27)Th4+(0.05)O2.27. is a variety of pitchblende discovered in China, and it is an important primary economic uranium mineral. The main difference between thorium-bearing pitchblende and pitchblende is the high ThOz content (1.79-10.03%)and high Th : U ratio ( 0.02-0.14 ). and it is similar to pitc}ablende in other chemical and physical properties. At medium-low temperatures, when ore solution has soufficient F-1 concent- ration which forms fluoride and complex compound with uranium and thorium, uranium and thorium can migrate together in the same solution. In the process of ore formation, uranium and thorium can not separate completely but preci- pitate together, because ore solution is rapitedly cooled. The discovery of tho- rium-bearing pitchblende indicates that the isomorphism replacement of uran- ium arid thorium not only takes place at high temperatures but also does under the conditions of medium-low temperatures.

摘要:The mentioned calciometasomatical production formed from magnesioskarns consists of harkerite, monticellite, salite-augite, grossular, gehlenite, vesuvianite and so on. It was sediment at favourable section of the various rocks of the magnesioskarns by the certain law. Formation of these mineral derived from series of mutual reaction between the skarns minerals and the components of thermal solution, and it was at the expense of special paragenesis of original minerals. The six minerals are associated each other by certain paragenesis, and its interrelation may be expressing by the triangular chemography in the ternary system Al2O,-SiO2-CaO. They make up a multisystem of six phases in the ternary system and have singular determinated topological type. The me- ntioned mineral assemblages are relate to geochemical behaviour of the iron and magnesium in the thermal solution. The chemical potential of the two components is determinate regularity of replacement of the mineral assembia- ges.

摘要:The pancreatic calculus fragments are usually composed of granules cemen- ted by the light yellow yellowish brown cementing material. There are many cavities, having different snaps, among the granules. The pancreatic calculus consists of the following two kinds of materials; (1)Calcium carbonate, occurring as crystalline calcite, of which the most granules and their cementing material of the pancreatic calculus are made. Accoramg to optical mennncation,X-diffraction, mirarea spectyoscopy and differential thermal analysis, physical and optical parameters of the pancreatic calculus approximate fo Those of natural calcite.(2)Phosphate, Occurs as crystalline substance, being microgranular or fibrous, It is usually distributed around the carbonate aggregates on the cavity walls and insert occasionally among the carbonate crystals as stringer veins. This phosphate resembles a synthetic compound, iron phosphate (FePO4)，in chemical composition, and X- ray diffraction characters. In view of the compositions and the texture of the pancreatic calculus in this pancreatolithiasis case the denatured and necrotic parts of the pancreatic entity are first precipited with calcium carbonate and later a little phosphate. These are the remaining traces of the pancreatic necrosis which is the result of chronic pancreatitis.