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Glaciotectonic deformation and geotechnical stability in open pit coal mining
Published in Raj K. Singhal, Geotechnical Stability in Surface Mining, 2022
Mark M. Fenton, Mark R. Trudell, John G. Pawlowicz, Carolyn E. Jones, Stephen R. Moran, D.J. Nikols
Regional surficial geology mapping of the Wabamun map sheet (Andriashek, et al., 1979) revealed much of the bedrock in the Lake Isle-Lake Wabamun-Saskatchewan River area had been glacially disturbed and deformed. Preliminary investigations at the Highvale Mine in 1983 (Fenton, 1983c; Fenton, et al., 1983) indicated that glacially thrust bedrock material was widespread and that the presence of this material was contributing to the highwall failure near the east end of Pit 03. Subsequent research revealed that the surficial deposits overlying the bedrock included extensive areas of glacially deformed bedrock material, as much as 50 m thick in places, overlain by a comparatively thin, discontinuous cover of till, glaciolacustrine clay, glaciofluvial silt, sand and gravel. Some areas mapped as lacustrine clay by Andriashek, et al. (1979) are now known to be glacially crushed and fragmented mudstone and shale.
Horizontal direction drilling research program – University of Waterloo
Published in Mark Knight, Neil Thomson, Underground Infrastructure Research, 2020
G.M. Duyvestyn, M.A. Knight, M.A. Polak
The University of Waterloo North Campus test site is located on a topographical high. Based on a surficial geology study conducted by Moodle (1983) that included the test site, the area is inferred to have irregular surface distributions of clayey silt (till) and fine to medium sand (melt water sediments). Moodle (1983) attributed the silt and sand units to the presence of a sloping outwash band or channel with fluctuating currents and velocities. The sand beds are reported to show an abundance of planar cross beds, climbing ripples, and erosion truncations. The typical soil stratigraphy observed across the test site is shown in Figure 5. A compilation of over 50 grain size distributions for the test site soils, shown in Figure 1, indicate that the site soils consist of three distinct units: clayey SILT with some sand,SILT with varying sand content and trace of gravel and clay, andSAND with trace of silt and clay.
Case-Speciflc Observations: Assembling and Exploring Data
Published in Susan B. Norton, Susan M. Cormier, Glenn W. Suter, Ecological Causal Assessment, 2014
Susan B. Norton, Michael G. McManus
Online sources of information, such as Google Earth and Google Maps, provide some of the first pieces of information available to assessors. Spatially referenced data (i.e., data layers) such as surficial geology, stream networks, and watershed boundaries are used to place site data into geographic context. In the United States, stream network information and watershed boundaries are available from the National Hydrography Dataset (FGDC, 2014). Other potentially useful data layers include land use and land cover information and boundaries for ecoregions, which are areas that are similar in vegetation, climate, soils, and geological substrate (U.S. EPA, 2014a). A growing number of databases make information on the location of hazardous wastes sites and toxic releases available to the public (e.g., U.S.EPA’s Envirofacts database; U.S. EPA, 2014b). Soil, water, and other data layers can be accessed from a compilation of over 200 resources for spatial data and analysis from U.S. EPA’s Geospatial Toolbox (Hellyer et al., 2011).
Integration of site condition information using geographic information system for seismic risk reduction for bridge network
Published in Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards, 2022
Azarm Farzam, Marie-José Nollet, Amar Khaled
The HVSR method was used to analyse fifty single measurements at selected bridge sites. Sites selection was based on the characteristics of the surficial geology and thickness of the sediment. Three conditions were defined. First, as mentioned previously, some geological deposits of the Lowlands (Figure 1 and Table 1) are not identified in any of the three municipal areas for which an analysis of the probable seismic site class was realised. Therefore, to complete the relation between surficial deposits and probable seismic site class, 14 lacustrine deposit or eolian sediment sites were selected. Second, some geological deposits, such as marine sediments, are more common than others (Table 1), and marine deposits are particularly more sensitive to amplification. Therefore, 14 sites on marine outcrops were selected. Third, other selected sites had geological characteristics corresponding to the case where probabilities do not strictly define one seismic site class, such as for marine deposits between 5 and 10 m of thickness, in Table 2.