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Subsidence hazards due to the dissolution of Permian gypsum in England: Investigation and remediation
Published in Barry F. Beck, Felicity M. Pearson, Karst Geohazards, 2018
The Permian geology of the area (Figure 1) comprises a lower carbonate aquifer (Cadeby Formation - 60m thick) overlain by up to 40m of gypsum then 10m of gypsiferous mudstone and mudstone of the Edlington Formation. This is followed by another carbonate (Brotherton Formation - 12m thick) overlain by up to 10m of gypsum then about 12m of mudstone of the Roxby Formation. The succession is capped by the red sandstones of the Triassic Sherwood Sandstone Group, the major regional aquifer, which attains 300m in thickness. The rocks dip eastwards at about 2–3 degrees. The Permo-Triassic strata are partially concealed by glacial and post-glacial deposits. In the vicinity of Ripon the bedrock is cut through by a deep valley, partially filled with Devensian glacial and post-glacial deposits up to 22m thick, that follows the course of the present River Ure. The deep buried valley intersects the carbonate and gypsum units creating a hydrological pathway from the bedrock to the river. The dip slopes of the carbonates and scarp of the Sherwood Sandstone act as groundwater recharge areas. In this situation considerable groundwater flow occurs and artesian water emanates from the Permian sequence as springs along the valley sides and up through the valley gravels, subsequently passing into the river. Artesian water with a head above that of the river has been encountered in some boreholes. Much of this water is saturated or nearly saturated with dissolved calcium sulphate indicating that considerable gypsum dissolution has taken place. Much of the sand and gravel partially filling the valley is cemented with calcareous tufa deposited from the sulphate-rich water which is also rich in dissolved carbonate (Cooper, 1988).
Modeling contaminant transport and biodegradation in groundwater
Published in Domy C. Adriano, Alex K. Iskandar, Ishwar P. Murarka, Contamination of Groundwaters, 2020
Hanadi S. Rifai, Philip B. Bedient
Sinclair et al. (1990) completed a survey of microbial populations in twenty-two aseptically collected sediment core samples. The cores were collected from below the water table (60 to 280 ft deep) at four pristine sites along a major buried-valley aquifer system in northeastern Kansas. Total counts of bacteria varied between 106 to 108 per gram of dry sediment. A relationship between sediment texture and microbial population density was confirmed statistically by the researchers. Total numbers of bacteria correlated highly with variations in sediment sand and clay content.
Analysis of causes of deformations in historic buildings on weak clay soils
Published in Rashid Mangushev, Askar Zhussupbekov, Yoshinori Iwasaki, Igor Sakharov, Geotechnics Fundamentals and Applications in Construction: New Materials, Structures, Technologies and Calculations, 2019
A.G. Shashkin, K.G. Shashkin, R.E. Dashko
The area of Telezhnaya street is confined to a low Litorina terrace, the datum varies from 7.5 to 8.2 m. A geological and lithological section is characteristic of the mentioned geomorphological structure. The bedrock—Upper-Kotlin clays of the Upper Vendian rocks—lies within the depths of 20–25 m, that is, the area is located outside the buried valley. Bulk soils, buried peat, lake-sea soils, lake-glacial (partially washed out) deposits and moraine can be traced in the section (from top to bottom) (Fig. 1).
Prairie water: a global water futures project to enhance the resilience of prairie communities through sustainable water management
Published in Canadian Water Resources Journal / Revue canadienne des ressources hydriques, 2019
Christopher Spence, Jared D. Wolfe, Colin J. Whitfield, Helen Margaret Baulch, Nandita B. Basu, Angela K. Bedard-Haughn, Ken W. Belcher, Robert G. Clark, Grant A. Ferguson, Masaki Hayashi, Karsten Liber, Jeff J. McDonnell, Christy A. Morrissey, John W. Pomeroy, Maureen G. Reed, Graham Strickert
Groundwater resources in the Canadian Prairie are drawn from a variety of aquifer types (Grasby et al. 2014). The Carbonate Rock aquifer of Manitoba, the Judith River Formation in Saskatchewan and the Paskapoo Formation in Alberta are regional bedrock aquifers, which are important for domestic, agricultural and industrial water supplies. Throughout much of the rest of the Prairie Water domain, and particularly where shallow bedrock aquifers are absent, inter-till sands and gravels and buried valley aquifers are often targets for groundwater withdrawals. Glacial till and glaciolacustrine clays act as confining units over most of the Prairie, and Cretaceous shales are also important confining units for deeper bedrock aquifers. Groundwater recharge through these confining units is often low (5–40 mm yr−1) (van der Kamp and Hayashi 1998) and there are numerous documented cases of groundwater with a long residence time (e.g. >10,000 years) in the region (Ferguson and Jasechko 2015). Groundwater recharge usually occurs under topographic depressions that collect snowmelt runoff water and allow it to infiltrate and percolate below the rooting depth (Hayashi et al. 2003). Much of the infiltration water for shallow groundwater recharge may be exhausted by evapotranspiration (Parsons et al. 2004), but a small fraction leads to low and steady deep groundwater recharge rates (van der Kamp and Hayashi 1998) important to the region’s shallow aquifers (100–200 m deep) commonly used for rural and urban water supply.
Spatial distribution of soil shear-wave velocity and the fundamental period of vibration – a case study of the Saguenay region, Canada
Published in Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards, 2018
Thomas Foulon, Ali Saeidi, Romain Chesnaux, Miroslav Nastev, Alain Rouleau
The glaciofluvial gravel provided a major modelling challenge as its boundaries are poorly known and the number of boreholes that penetrate this unit is insufficient to provide a good characterisation (CERM-PACES 2013). In the Laterrière-Bagotville corridor, this unit presumably lies between the till and the clay layers. The limits of this unit were defined using several borehole data, the simplified contours established by Lasalle and Tremblay (1978) and existing knowledge related to the deposition of the glaciofluvial deposits. The latter was particularly important as a substitute for the scarce information on the form and the thickness of the glaciofluvial gravel layer. The extent of this unit was inferred from the limits of the buried valley as observed from the bedrock topography in the Laterrière-Bagotville corridor, with a greater thickness assigned to the bedrock valley basins and thinner deposits along the upper portion of the bedrock between the basins.