盘山花岗岩裂隙水元素成因

作者通过对比各种成因裂隙水性质，判断表生条件下水岩地球化学作用方向，分析影响裂隙水中可溶组份含量变化的各种因素，分析裂隙水中可溶组份之间相关关系，旨在探讨盘山花岗岩裂隙水中主要元素的成因问题。

Platinum-group Elements Geochemistry of the Yangliuping Magmatic Ni-Cu-PGE Sulfide Deposit:Implications of Its Genetic Link with the Extrusive Basalts

Primitive mantle normalized Platinum group elements (PGE) concentration patterns for the Zhengziyanwo intrusion and Dashibao Formation basalts are of positive slope, similar to most of the world class magmatic Ni Cu PGE sulfide deposits. Characters of this intrusion and its related ores and Dashibao Formation basalts are their negative Pt anomaly and high concentration of Rh relative to Pt and Pd, facts being interpreted to be the results of crystallization and fractionation of Pt alloys and spinel phase free crystallization history for the magma, respectively. PGE parameters of the Dashibao Formation basalts are consistent with the general trend of those found for the Zhengziyanwo intrusion, and this might infer a genetic link between them.

Geochemical characteristics and petrogenesis of volcanic rocks from Baiyingaolao Formation in northeastern Hailar Basin

The volcanic rocks from Baiyingaolao Formation in the northeastern Hailar Basin are mainly composed of rhyolite and trachydacite. U-Pb dating of zircon shows these volcanic rocks formed in Early Cretaceous( 128--124 Ma). Geochemical data indicate that they are sub-alkaline series in composition and rich in alkali and potassium. All samples have similar rare earth element patterns characterized by high total rare earth elements contents( ∑REE = 113. 96 × 10- 6-204. 33 × 10- 6),significant fractionation of heavy and light rare earth elements( ∑LREE / ∑HREE = 3. 10-4. 52) with middle negative Eu anomalies( δEu = 0. 46-0. 76).The trace elements are characterized by enrichment in large-ion lithophile elements such as K,Rb,LREE and depletion in high field strength elements e. g. Nb,Ta,HREE,P and Ti,while enriched in Th and U. Rhyolite and trachydacite contain low initial87 Sr /86 Sr ratios( 0. 704 9--0. 7 053) and positive εNd( t) values( ca. 4.15). These data suggest that the magma of rhyolite and trachydacite were derived from mafic lower crust newly accreted from mantle,with the evolutional trend of comagmatic fractional crystallization.

Characteristics of the genetic mineralogy of pyrite and its significance for prospecting in the Denggezhuang gold deposit,Jiaodong Peninsula,China

This paper reports the variation rules for the typomorphic parameters of the pyrite and the gold enrichment rules of the Denggezhuang quartz vein gold deposit at a large-depth scale, providing the mineral signs for deep prospecting prediction through detailed study of the characteristics of crystal＇ habits, chemical composition, the thermoelectricity of pyrites, and min- eralogical mapping. This paper primarily discusses the correlation between the mineralization intensity and the space-time evolution of the mineralogical parameters, clarifies the physicochemical conditions during gold mineralization, and provides information useful for deep mineralization prediction. We demonstrate that the crystal habits of the pyrites are very complex, primarily occurring as （ 100）, （210）, and their combinate form. （210） and （ 100）＋（210） have positive correlations with gold mineralization, and （ 100）＋（210） therefore can be useful for locating rich ore segments. The composition of pyrites is charac- teristically poor in S and rich in As. Their typical trace elements are composed of Mo, As, Pb, Cu, Bi, Zn, Au, Co, Se, Sb, Ag, Ni, Cr, and Te. The average contents of trace elements in pyrites from various stages show that the crystallizing temperature gradually decreased from an early stage to the metallogenic episodes. The precipitation and accumulation of Au and Ag occur primarily in the quartz-pyrite stage （III） and the polymetal minerals stage （IV）. The occurrence rate of P-type pyrites （P（%）） is 83.52%. There is a larger dispersion of the thermoelectrical coefficient of pyrite （a） in the Denggezhuang gold deposit than in other deposits in the Jiaodong Peninsula. The electrical conductivity assemblage of pyrites from I to V is characterized by P〉N〉P〉N〉P〉〉N〉P〉〉N〉P〉N, which is usually considered beneficial for mineralization. The relative contents of As＋Sb＋Se＋Te and Co＋Ni are closely correlated to P-type and N-type average values and their occurrence rates. According to the crystallizing temperature of pyrite, the mineralization intensity, and the denudation degree, the mineralization temperature of the Denggezhuang gold deposit is in the range of 150-322~C and is of a medium-low temperature. The orebody has already become denuded to the top-middle of the orebody, and the size of the orebody is larger than 900 m. Based on the vertical zon- ing of the thermoelectrical coefficients of pyrites and P-type pyrite mapping, it is suggested that the segment between -425 and -800 m may have exploration potential to the northeast of line 94 of the No. I2.2 orebody.

Description of Soil Evolution in Southern Mashhad City Using Jenny＇s and Johnson and Watson-Stegner＇s Conceptual Models

Conceptual models are suitable for describing internal relationships of complex systems, including soil. We used conceptual models, the Jenny＇s and Johnson and Watson-Stegner＇s models to understand the formation and evolution of soil. We studied 20 pedons in granitic hilly lands, loessial piedmont, and piedmont plain in southern Mashhad, northeast Iran. These soils were characterized by high levels of gypsum, especially in the granitic saprolites, which suggested the importance of the wind in shaping the soil structure. Jenny＇s model is a developmental and equilibrium model, which only describes the state of the soil formation factors and considers that each bioclimatie zone has a specific climax soil. It focuses on the genesis of the surface soil and is not suitable for buried soils and paleosols. Johnson and Watson-Stegner＇s model describes soil as a product of progressive and regressive processes due to horizonation or haploidization. Progressive processes during the last interglacial cycle created a well-developed paleosol with an argillic horizon in all landforms, except the piedmont plain. Developmental soil up-building by aeolian addition led to gypsum enrichment of the granitic saprolite. Erosion decreased soil thickness and exposed the argillic horizon. The Last Glacial Maximum led to greater deposition of loess, covering the paleosol. Humidity was higher during the early Holocene than today, leading to the development of a Bk horizon. This horizon was preserved in the stable surfaces of granitic hilly land and in the loessial piedmont, but buried on the piedmont plain via the deposition of alluvial sediments. Jenny＇s model could be used for current soil formation factors, whereas Johnson and Watson-Stegner＇s model required morphological characteristics of pedons for interpretation.