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Basic Principles
Published in Kathleen Sellers, Fundamentals of Hazardous Waste Site Remediation, 2018
A layer of fill covers many sites in developed areas. Fill, which may comprise soil, ashes, and/or mixed debris, was placed at many sites to fill in a wetland and make usable land, to level natural ground contours, or to dispose of waste. Natural geologic formations include unconsolidated deposits and rocks. Unconsolidated deposits are soils originally deposited by glaciers, water (such as river sediments), or wind (such as sand dunes). Unconsolidated deposits include materials such as gravel, sand, silt, and clay. These materials are characterized by their particle size, as indicated in Table 2.6. Rock formations include consolidated sedimentary rocks such as sandstone, shale, and limestone, igneous rocks, and metamorphic rocks such as granite, basalt, slate, or gneiss.
Rock mass formation
Published in Ivan Gratchev, Rock Mechanics Through Project-Based Learning, 2019
Rock formation is a complex process that occurs in the lithosphere, and it is accompanied by tectonic activities such as plate movements. According to plate theory, the lithosphere is broken into plates, which slowly move above the asthenosphere (Figure 3.2). The collision (Figure 3.2a) or subduction (Figure 3.2b) of plates results in the formation of ridges or trenches, respectively, accompanied by volcanism and earthquakes. These tectonic movements can (a) rupture rock mass, forming faults and (b) deform rock mass by creating folds. In both cases, the engineering properties of rock mass will alter (that is, the rock mass will become jointed and more susceptible to weathering).
Basic aspects of Environmental Geotechnics education
Published in Iacint Manoliu, Ion Antonescu, Nicoleta Rădulescu, Geotechnical Engineering Education and Training, 2020
The “Geoengineering” specialization is aimed at preparing a professional figure that can work in the field of Engineering Geology. The main activities that can be developed by this kind of specialized engineer are: design and construction management of underground structures, excavation works and slope stability involving rock formations. The list of subjects, for this specialty area, reported in Table 4, are mainly related to traditional “Geotechnical Investigations and Monitoring”, “Rock Mechanics”, and “Soil Improvement” subjects.
Development of new composite index on channel sensitivity using AHP, FR and ensemble model and its application on the Mayurakshi river of Eastern India
Published in International Journal of River Basin Management, 2022
Abhishek Ghosh, Ramkrishna Maiti
The river Mayurakshi flows through nearly confined undulating Chhotanagpur plateau fringe, semi-confined Para-deltaic fan surface and unconfined recent flood plain in the upper, middle and lower parts, respectively. In the upper part of this river basin, Granite, Gneiss and metamorphic rock formation (hard and massive structure) of Archaean and Proterozoic era is mostly seen. In the middle reaches, hard Lateritic formation and Rampurhat (mainly hard clay) formation of the Cainozoic and Late Pleistocene is predominantly noticed. But, the eastern part of the Mayurakshi river basin is composed with active flood plain deposit known as Kandi formation (alternative soft layers of the sand, silt and clay) which dates back to Middle and upper Holocene time (Figure 2(a–c)). This river has successively developed a nearly straight course, braided pattern, wandering shape and sinuous passages in upper, upper-middle, middle and lower reaches, respectively. The relative analysis shows that the channel gradient, flow depth, width-depth ratio, degree of channel incision and bank steepness are high in lower parts of the river (Figure 3 and Table 1). Regional variations to geological formation, topography and pedological composition have a significant influence on planform geometry and channel morphology which in turn manoeuvred the processes related to river bank erosion, transportation and deposition (Bhattachrayay, 2013; Ghosh & Mukhopadhyay, 2015; Ghosh & Pal, 2015; Mukhopadhyay & Das, 2013).
Feasibility of wet-extraction of phosphorus from incinerated sewage sludge ash (ISSA) for phosphate fertilizer production: A critical review
Published in Critical Reviews in Environmental Science and Technology, 2021
Le Fang, Qiming Wang, Jiang-shan Li, Chi Sun Poon, C. R. Cheeseman, Shane Donatello, Daniel C. W. Tsang
The uneven distribution of the currently known deposits of P-rock ensures that most countries rely on importing P-rock, intermediary derivatives or final P-based products. Even in countries with considerable P-rock deposits, current consumption rates would consume those deposits completely in the next 15–40 years. As shown in Figure 1, approximately 80% of global P rock reserves are located in Morocco and Western Sahara, China and Algeria (U.S. Geological Survey (USGS), 2015, 2017, 2019). These deposits exist mainly as the sedimentary rock formation with some igneous occurrences (Desmidt et al., 2015; Van Kauwenbergh, 2010). According to FAO (2015), the major users of P resources are China, India and the United States, and the consumption amounts are related both to size of population and agricultural productivity (including for export). Particularly, the local demand significantly outstrips its supply in less developed regions with huge population, for example Latin America and Asia whose population almost accounts for 70% of the world total (FAO, 2015; United Nations (UN), Department of Economic and Social Affairs, 2019). The inadequate local P-rock deposits and huge demand for P fertilizers will eventually result in most of the countries in the world importing P-rock or P fertilizers from Morocco and Western Sahara in the future. In Europe, concern about the future supply of P-rock has resulted in it being listed as a critical raw material by the European Commission in May 2014.
Landslide susceptibility assessment in the Nantian area of China: a comparison of frequency ratio model and support vector machine
Published in Geomatics, Natural Hazards and Risk, 2018
Faming Huang, Chi Yao, Weiping Liu, Yijing Li, Xiaowen Liu
The lithology affects the probability of the landslide occurrence through affecting the shear strength and permeability of rocks and soils (Van Westen et al. 2008). Three main types of lithological units distribute in the Nantian area: volcanic sedimentary rock formation; pyroclastic rock and volcanic lava rock formation, intrusive rock and sub-volcanic rock formation (Figure 4). Different lithological units have different frequency ratios as shown in Table 1, a total of 62.63% of the landslide grid cells occur in the area with volcanic sedimentary rock formation, the frequency ratios of these landslide grid cells are 1.53.