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Main technologies and potential analysis on artificial recharge in Beijing
Published in Peter J. Dillon, Management of Aquifer Recharge for Sustainability, 2002
Z.J. Yao, Y.C. Gao, Y. Lu, L. Shen
The main areas suitable for artificial recharge in Beijing are beside rivers and channels. According to lithology, structure and water content capacity of aquifer, it can be divided into three regions: 1) the top region of alluvium and colluvium, where the lithology is single-layer gravel. It is the main region for groundwater replenishment with good water storage capacity. The pumping capacity for a single well is more than 5000m7d (60L/s). This region is located at the upper reaches of the river; 2) the middle region of alluvium and diluvium, where the lithology of aquifer is multi-layer gravel. It belongs to the transition region between the phreatic water and confined aquifer region. The pumping capacity for single well is more than 2000m7d (24L/s). This region is located in the middle reaches of the river; 3) the lower region of alluvium and diluvium, where the lithology of aquifer is sand with poor water storage capacity. This is found at the lower reaches of the river.
Development of the Suspension Method
Published in T. Adachi, K. Tateyama, M. Kimura, Modern Tunneling Science and Technology, 2020
Typical borehole data is indicated on the section of the subway crossing in Figure 2. The surface level is OP+2.0m to +4.0m. The soil profile consists of an alluvium sand layer (As), overlying an alluvium clay layer (Ac), a diluvium sand layer (Ds), and a diluvium gravel layer (Dg). The existing tunnel was situated on the Ac layer. The unconfined compressive strength (qu) of the soil is 100 to 150kPa. Although not as soft as many alluvium clays, the remolding sensitivity is high, being greater than 30. The temporary point-bearing piles used were founded in the Ds layer. The permeability of this layer is very high, as is the water table.
Study on the design and protection of a subgrade side slope in the distribution area of loose accumulation bodies
Published in Xiaoling Jia, Feng Wu, Electromechanical Control Technology and Transportation, 2017
The riverbed and bank are mostly made of alluvium and diluvium layer, covered with sandy pebble soil of high strength. The edge of subgrade is far away from the top edge of the slope of riverbed, and it is demonstrated by the survey that there is generally no subsidence and collapse of subgrade in the existing highway caused by flood damage. The subgrade does not locate in the wash zone of the riverbed, and the subgrade need not be treated in principle.
Building Damage Caused by the 2017 M5.4 Pohang, South Korea, Earthquake, and Effects of Ground Conditions
Published in Journal of Earthquake Engineering, 2022
Byungmin Kim, Yumin Ji, Mirae Kim, Young-Joo Lee, Hyeonggu Kang, Nu-Ri Yun, Hyewon Kim, Junghan Lee
Figure 7(b) shows the geology map of Pohang city obtained from the Geological Survey of Korea (1964). The study area consists of Quaternary systems (Qa: alluvium; Qd: Diluvium), various Tertiary systems (Td: Duho Formation; TE: Idong Formation; Th: Heunghae Formation; Ty: Yonam Formation; Ta: Hakrim Formation; Tc: Cheonbuk Conglomerate; Clc: Lower coal-bearing formation; Cka: Kyuryuho andesite; Coch: Chunbuk Conglomerate; and Esh: Ennichi shale), and Cretaceous systems (Li: Liparite; and Gb: Biotite Granite). It is worth noting that most of the damaged buildings are located in the Tertiary Duho Formation (Td) adjacent to the Quaternary alluvium (Qa) region in the east (see Figures 7a and 7b). The ratios for the Damage Grades are high for Td as shown in Figure 9. Generally, the Tertiary rocks exist in the mountains. However, the Tertiary Formation regions, where the building damages are concentrated, are flat. In fact, many buildings are located in the transition zone between the tertiary rock hill-Quaternary alluvium basin (i.e., the basin edge) because the grounds are relatively firm and flat. The effect of this basin edge is further discussed in subsequent sections. The ratios for Damage Grades 2 and 3 are highest for Th. This is because this formation is near the epicenter where the estimated PGAs are large.
Spatiotemporal distribution and failure mechanism analyses of reservoir landslides in the Dagangshan reservoir, south-west China
Published in Geomatics, Natural Hazards and Risk, 2018
Shi-lin Zhang, Peng-fei Lv, Xing-guo Yang, Xing-ze Chen, Jia-wen Zhou
The study area is located at the junction of the Yangtze platform and the Bayan Har geosynclinal fold system and has experienced the effects of magmatism and intense tectonism. The exposed stratum exhibits a complex evolutionary history and presents the characteristics of multiple types and multiple causes of deformation. The stratigraphic bedrock is mainly composed of basic–ultrabasic rock, which consists of diorite and granite from the Jinning-Chengjiang period. Meanwhile, the Sinian, Devonian and Permian strata are widely distributed along the right bank and constitute a set of shallow metamorphic terrigenous clastic rocks as well as carbonate rocks. Furthermore, the Triassic Baiguowan group (T3bg) is only distributed locally in the middle section of the reservoir and the tail section of the reservoir, both sides of which are restricted by the eastern and western branches of the Dadu River fault. Simultaneously, due to the influence of the Dadu River fault, soft lithologies (sandstone and shale) and the effects of weathering and unloading, this stratum exhibits well-developed structural surfaces and fractures (as shown in Figures 2(b,c)). In addition, there are large volumes of Quaternary deposits on both sides, which present different distinct historical sedimentary layers (as are shown in Figures 2(d,e)), which were mainly initiated as alluvium, diluvium and colluvium, or as ancient landslides. These landslides and/or slope instability problems mainly occur in Quaternary deposits, strongly weathered and fractured rock masses, and soft rock masses with heightened sensitivities to water.
Distribution and Statistical Analysis of Chemical Elements in Soil from the Territory of the Republic of Kosovo
Published in Soil and Sediment Contamination: An International Journal, 2023
Granit Kastrati, Ramë Vataj, Flamur Sopaj, Krste Tašev, Trajče Stafilov, Robert Šajn, Musaj Paçarizi
The Republic of Kosovo, located in the central part of the Balkan Peninsula, has an area of 10,908 km2. It is estimated that 15% of the soil is of high quality, 29% is of medium quality, and 56% is of poor quality (Daci-Zejnullahi 2014). The geology of Kosovo is very diverse, both in terms of formation time and composition. There are rocks from the Proterozoic to the Quaternary age. The oldest rocks in Kosovo, which are located in the eastern part (Kamenica), belong to the Neoproterozoic age and are represented by rocks (gneisses, slates, etc.). Paleozoic formations are found in different parts of Kosovo, such as the Albanian Alps (Kosovo), Accursed Mountains, Sharri Mountains, Karadaku, Blinaja, Artana, etc. They are represented by crystalline shales with a low degree of metamorphism. The Mesozoic formations have a large extension on the territory of Kosovo and consist of sedimentary and magmatic rocks. They are located in the mountains of Sharri, Accursed Mountains, Mokna, the mountains of Has and Pashtrik, the peripheral mountains of Drenica, the Eastern Mountains, etc. Cenozoic formations are widespread in the plains of Kosovo, forming the field pits of Dukagjin, Kosova, Anamorava, Llapi, and Drenica, while glacial deposits are found in the upper parts of the mountains. Besides sedimentary rocks (limestone, marl, clay), volcanic rocks (Miocene) are also encountered, which influenced the occurrence of Pb-Zn mineralization in some mines of Kosovo (Trepçë, Artanë, Hajvali, Kizhnicë, Badoc, etc.). During the Neogene, through tectonic movements, mountain ranges and pits were created on the Balkan Peninsula. The pits in Kosovo were covered by the waters of the lakes, in which later friable deposits (sand, clay, and gravel) and coal (lignite) were deposited. The youngest geological sediments are found along rivers (alluvium), on slopes (diluvium), and in dry parts of mountains (glacial moraines) (Figure 1) (Z Elezaj and Kodra 2008, 2012). The main economic sectors are agriculture, energy, and mining.