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Geological technology of grade mapping of non-metallic raw materials as the basis of its profitable mining
Published in Genadiy Pivnyak, Volodymyr Bondarenko, Iryna Kovalevska, Theoretical and Practical Solutions of Mineral Resources Mining, 2015
The difference in means of qualitative indicators on the stratigraphie horizons and average weighted on the thickness proves the advantages of selective mining. The most high-quality limestone belongs to the horizon of C1td. It is the top part of Tournasian sediments. The most low-quality limestone belongs to the horizon of C1ta1. It is the lowest lay of the carbonate strata which is characterized by interbedding of clays, dolomite and the dolomitized limestone. There are the most common all secondary processes in deposit.
Contaminant Case Studies
Published in Daniel T. Rogers, Urban Watersheds, 2020
The geology of the site is an interbedding of sand, silt, and small clay lenses to groundwater encountered at a depth of approximately 70 feet beneath the surface. Groundwater is present in a complex network of aquifers that are used as a potable source of water and the aquifers are also used to store billions of gallons of water for potential future use. Groundwater beneath the site is flowing toward a river located approximately 4 kilometers from the site toward the west.
Applicability of seismic geotomography to rock classification of Okawara Tunnel, Kyushu, Japan
Published in Jian Zhao, J. Nicholas Shirlaw, Rajan Krishnan, Tunnels and Underground Structures, 2017
H. Kochihira, T. Nakazuka, Y. Yokoi
The Okawara Tunnel is a road tunnel with a width of 10m located on one of the small islands in the Kyushu area of western Japan. The tunnel was finished in March 2000. The tunnel penetrates 160m through Tertiary sedimentary rock (sandstone-shale interbedding rock) and the maximum overburden is about 30m. The sandstone is moderately strong and the shale is moderately weak. The upper part of the sedimentary rock is severely weathered and changed into residual soils.
Oil-bearing evaluation of different lithofacies in Da’anzhai Member, Central Sichuan Basin: implications for shale oil development
Published in Petroleum Science and Technology, 2023
The organic matter of source rock will shine brightly under fluorescence irradiation. Under the same organic matter type conditions, the higher organic matter content means the stronger fluorescence intensity. Fluorescence under the microscope is an important manifestation of oil in rocks (Teichmuller and Wolf 1977). In Figure 2, core photos and fluorescence show different oily characteristics in different lithologies. Oil stains are visible on the core surface of the shell limestone (Figure 2a and 2g) in the Da’anzhai Member. Under the microscope, we can see green fluorescence in the shell interior and fractures, showing that the shell limestone has a certain degree of oil-bearing characteristic. There are obvious oil stains and oil smell on the core surface of Da’anzhai shale (Figure 2b and 2c), indicating the overflow after filling the pores with oil. Under the microscope, many micro-fractures with good continuity show light green fluorescence (Figure 2e), meaning the shale has good oil content. In theory, this kind of crude oil stored in micro-fractures has the best liquidity, making it is the easiest to be exploited. Some yellow fluorescence spots in the matrix pores (Figure 2f), suggesting that the shale has a certain degree of oil-bearing characteristic in matrix pores. The peperite (Figure 2d) in the Da’anzhai Member refers to the interbedding of shale and shell limestone with shale and shell limestone ratio close to 2:1. Some green fluorescence spots can be observed in the peperite under the microscope (Figure 2h), indicating that the peperite has a certain degree of oil-bearing characteristic.
Logging evaluation of petrophysical facies based reservoir quality prediction method for the volcanic rocks in the deep depth of Nanpu Sag, China
Published in Petroleum Science and Technology, 2023
Qiuli Yin, Weibiao Xie, Guiwen Wang, Defang Liu
In the study area, a total of 10 datasets of borehole image logs, wireline logs and cores have been collected for lithofacies interpretation. Contrasting cores with conventional well logging characteristics and electrical image appearance, the interpreted lithology includes basalt, tuff, tuff/claystone interbedding, tuffaceous sandstone, tuffaceous claystone, diabase and slate. The calibrated volcanic structures mainly include massive structure, bedding structure, interbedding structure, fluidal structure and amygdaloidal structure. Based on the lithology and structures, dominant lithofacies can be determined. The proposed lithofacies evaluation method using well logging can be inferred for a direct lithofacies interpretation of volcanic rocks when cores are unavailable. Wireline log responses of the volcanic rocks with different lithofacies in the study area are shown in Table 4.
Study on Large Deformation Control Technology and Engineering Application of Tunnel with High Ground Stress and Weak Broken Surrounding Rock
Published in Structural Engineering International, 2020
Xiangyong Kong, Xu Chen, Chun’an Tang, Zhaorui Sun, Enhuai Hu
According to the on-site conditions of Ruyi tunnel, the width and height of the model are all 64 m, which is enough to ignore the boundary effect, and the tunnel is in the center of model. Because the lithology of the tunnel surrounding rock is relatively single (mainly sand-shale interbedding), and the inhomogeneity of the rock mass is fully taken into account, the surrounding rock is simplified as a same rock material. In the model, the homogeneity coefficient of elastic modulus and uniaxial compressive strength is 3, the homogeneity coefficient of Poisson ratio and density is 100,21 the strength reduction factor is 0.01, and other physical and mechanical parameters are shown in Table 1. Vertical stress of 3.7 MPa is applied on the upper boundary, and the horizonal stresses of 9.01 MPa are applied on the left and right boundaries. The bottom of the model is set to vertical displacement constraint. In addition, the numerical simulation only conducts a qualitative analysis of the tunnel failure process, and does not discuss quantitatively the stress fields, so the scales are not shown in the pictures.