Advanced Materials Research Vols. 524-527

Abstract: The paper studies on the geochemical characteristics of major element, trace element and REE of granite, marble and skarn in Xinshan Area in Kafang. The studies have shown that the granite in Xinshan Area is high-potassium calc-alkalic granite. The distribution plots of REE in different lithological rocks have obvious differences, but all three different lithological rocks have the characteristic of LREE enrichment. The ratio of LREE to HREE of Marble and skarn is larger, while that ratio of granite is smaller. The variation of LREE and HREE of Skarn is large, indicating that REE occurs significantly different in the migration process and the extent of wall rock material exchange.

Abstract: Total energy, maximum peak amplitude and RMS amplitude are sensitive to sand body, and they are non-linear relations with sand thickness. In this study, a three-layer BP neural network is employed to build the prediction model. Nine samples were analyzed by three-layer BP network. The relationships were produced by BP network between sand thickness and the three seismic attributes. The precise prediction results indicate that the three-layer BP network based modeling is a practically very useful tool in prediction sand thickness. The BP model provided better accuracy in prediction than other methods.

Abstract: Langdu is one of the highest grade, skarn copper deposits in Zhongdian area, Yunnan province. The chondrite-normalized REE patterns for syn-sulfide calcite from Langdu deposit are unique, being HREE-enriched, LREE-depleted and have significant positive Eu anomalies. REEs could derive from magmatic fluid exsolved from near melt. This distribution behavior is predominately constricted by REE patterns of hydrothermal fluid and the stability of complex in solutions than crystallographic factors. The D_REE are increase with the decrease of ion radius. The optimum ion radius of substitutional site for REEs in the hydrothermal calcites is 0.1032nm. Eu occurs as Eu ²⁺ and complex species can explain the positive Eu anomalies

Abstract: Rift basin is an important petroleum basin type, in which about one third of oil and gas was discovered. To research on the main controlled elements of oil and gas accumulation, five typical rift basins in Europe are focused on the geological condition such as source rock, reservoir, seal, petroleum system, and accumulation with logging, hole, measured and analytical methods, and so on. The results showed the main regional seal controlled the petroleum distribution in the rift basin. Seals are defined by main regional seal, minor regional seas and local region according to thickness, distribution, lithostratigraphy. Viking Graben of North Sea has main regional seal about 3000m thick during late Jurassic and Cretaceous, about 81 percent of petroleum is in the Jurassic reservoir; Anglo-Dutch basin has main region thick seal during Triassic through Jurassic, and Permian reservoir accounted for 73 percent of basin reserves; Voring Basin has the main regional seal during Cretaceous through early Tertiary, the Jurassic reservoir has 85 percent of whole basin reserves; Northeast and Northwest Germany Basins have the evaporites as main regional seals during late Permian, and Permian reservoir accounted for more than 80 percent of basin reservoir, respectively. Rift Basin can develop reservoir like turbidite, source rock, seal in the basin dynamic opinion. Some main regional seals may develop overpressre because of quick subside and hydrocarbon generation at some conditions, it can strengthen seal capability. Oil and gas can migration to the main regional seal by normal faults caused by rifting, which can stop further migration so that they were accumulated under the main regional seal.

Abstract: This paper takes X block as the target area, on the basis of logging data, the core information, dynamic production information, with high-resolution sequence stratigraphy demonstrating two-separability of PI3₃ systematically from the angle of sedimentology, namely, this layer is a sedimentary complex of the two river stage. We have analyzed the characteristics of remaining oil in the compound sandbody. Each channel sandbody has its own respective characteristics in the vertical water flood. As a whole at the bottom, the extent of water flood is high, and it weakens gradually until non-flooded with the level raising. It provided the basis for the study of the single sandbody architecture and the advance of the recovery ratio.

Abstract: Reservoirs in point bars of meandering channels account for a high proportion in oil and gas reservoirs, with much impact of complicated architecture on remaining oil accumulation and distribution. Thus study on inner architecture of point bars and its impact on remaining oil distribution are important. This paper selects Unit III in Block A in Daqing Oilfield with data in filled well patterns and cores to study inner architecture of subsurface single sand bodies, and analyzes 3D structural features of meandering point bars in Xingbei deltaic plain in Daqing Placanticline. Architecture parameters of lateral accretion shale interbeds are: eastward dip averagely 7°, the upper, middle and lower dip in same accretion face are respectively 10°, 7° and 3°, the width is 15-42m. They are vertically imbricated series and areally corner points of abandoned channels on both sides of meandering rings as track collection intersections, and progressive and curvature reducing arc sets with abandoned channels of meandering rings as outer boundary. This pattern provides geologic basis for successive study on remaining oil.

Abstract: The calcite of Fankou zinc-lead desposit was divided into four kinds, the frist three of them were studied with a depth. The frist calcite was unrelated to mineralization (∑REE=8.277×10^-6, LREE/HREE=3.866, δEu=0.997, Pb+Zn=5.02× 10^-6, δ¹³CPDB=-1.307‰, δ¹⁸OSMOW=15.7‰, ⁸⁷Sr/⁸⁶Sr=0.7161); the second calcite in mainly metallogenic stage which was fromed by mineralizing fluids (∑REE=43.624×10^-6, LREE/HREE=16.047, δEu=2.284, Pb+Zn=9.065×10^-6); the third calcite in late metallogenic stage which was fromed by remaining solution (∑REE=14.731×10^-6, LREE/HREE=3.112 δEu=0.705, Pb+Zn=4.84×10^-6). The second and third calcites were product fromed by the mineralizing hydrothermal (δ13CPDB=-6‰, δ¹⁸OSMOW=18.43‰, ⁸⁷Sr/⁸⁶Sr=0.7136). Two types of fluids exsist in Fankou Pb-Zn desposit, the frist fluid fromed the first calcite which comed form formation water, unrelated to mineralization; the second fluid fromed the second and third calcite which comed form deep seated hydrothermal of the mine areas, was mineralizing fluid, the properties of the second fluid changed relative reducing in mainly metallogenic stage into relative oxidizing condition in late metallogenic stage. From the surrounding rock to ore, δ¹³C and ⁸⁷Sr/⁸⁶Sr were gradually deceased of the calcite, but Pb, Zn, Cu, ∑REE and δ¹⁸O were gradually increased, these laws is similar to that of Mississippi Valley-type (MVT) deposit, and provide guiding significance for prospecting new ore bodies.

Abstract: The The mechanical properties of reservoir rock are more complicated and the various mechanical parameters of rock itself have a strong uncertainty. The mechanics characteristics of rock in the study area can not be well determined if only a limited number of experimental datas. Therefore, in this paper, the third segment of Wumishan formation in Renqiu oilfield is taken as an example, the probabilistic models are used to describe the uncertainty of the rock mechanical parameters based on ANSYS, in which predict and analyze the degree of fracture development at key wells in the target layer of the study area.

Abstract: Flow units are divided into E,G and P types for the Lower S₂ reservoir of Wen-X fault block in the Wenliu Oilfield, which are identificated based on six parameters including porosity, permeability, sandstone thickness, effective thickness, formation conductivity and flow index. A 3-D model for the flow units is established by sequential gaussian stochastic simulation approach. It is believed that type- E flow units are well exploited, with the distribution of the remaining oils related to fault as a barrier；type-G flow units are less exploited, with enrichment of remaining oil, due to the influence of interlayer or lateral heterogeneity；and type-P flow units are difficult to be exploited because of the poor percolation and a lower reserves abundance

Abstract: The paper has introduced that Chinese nuclear power development plan and the present situation of domestic uranium resources, and pointed the ways and methods to increase possible new uranium resources. Based on the demand and situation, the new situation of uranium resources development of related countermeasures was proposed briefly in this article. First, it strengthens uranium exploration; prospecting for deep concealed deposit, fill the gaps, further find out favorable area of uranium mineralization. Second, it actively develops the exploitation of overseas uranium resource and looking for a variety of forms of investments, and adopts the flexible ways of cooperation, in order to increase the uranium resources as far as possible. Third, the mining industry structure was optimized, the technology level was improved, the production cost was reduced, and the scale of production was expanded, carried out the dominant role of mining and the subsidiary role of diversified economy of multiple structured management patterns to promote local economic rapid development. Fourth, it should be perfected related policy laws as well as regulations about uranium resources development, and establish a perfect system of assets income distribution.