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Special Fill Materials and Problematic Subsoils
Published in Jan van ‘t Hoff, Art Nooy van der Kolff, Hydraulic Fill Manual, 2012
Jan van ‘t Hoff, Art Nooy van der Kolff
Fluvio-glacial soils have been transported and deposited by meltwater and are therefore more sorted and stratified than tills. Many of such deposits consist of gravel and sand characterised by low relative densities. Pockets of very low density can generate geotechnical problems in foundation works. Also voids may appear during or even after construction, possibly caused by melting of ice blocks that have been deposited within the gravel (Price, 1986).
Geomorphic responses of uplifted mixed sand and gravel beaches: combining short-term observations from Kaikōura, New Zealand with longer-term evidence
Published in New Zealand Journal of Geology and Geophysics, 2023
Kate E. MacDonald, Deirdre E. Hart, Sebastian J. Pitman
MSG beaches, relative to other beach types, have been typically neglected in international coastal research (Dawe 2001; Mason and Coates 2001). They are less commonly studied than sand beach types. They are plentiful at high/low latitudes, such as in New Zealand, Canada and Alaska, where there is a high wave energy, cold climate (Buscombe and Masselink 2006) and para- or fluvio-glacial source of coarse sediment (Zenkovich 1967; Kirk 1980). However, existing literature surrounding MSG beaches is highly localised to New Zealand (Jennings and Shulmeister 2002), in particular Hawke’s Bay (Single 1985; Paterson 2000; Ivamy and Kench 2006; Komar 2010; Dickson et al. 2011; Brown 2017), the Canterbury Bight (Kirk 1969; McLean and Kirk 1969; Kirk 1980; Pitman et al. 2019a, 2019b) and Kaikōura (McLean and Kirk 1969; McLean 1970; Kirk 1975; Dawe 1997, 2001).
Cryogenian glaciomarine megaclasts of the MacDonald Corridor, Bimbowrie Conservation Park, Olary Region, South Australia
Published in Australian Journal of Earth Sciences, 2020
Unlike MCs 7–10, the Old Boolcoomata Megaclast (MC 6) does appear to be a detached basement block composed of distinctly bedded sandy, silty and pelitic metasediments of the Tommie Wattie Formation that crops out nearby. MC 6 can be seen to be underlain and supported by OBCM conglomerate, because the hosting paleovalley is exposed in cross-section (Figure 12) (Preiss, 2006). MC 6 provides a unique example of the earliest stage of transport because it is near its basement parent that forms part of the eastern edge of the Old Boolcoomata glacial paleovalley. The rounded granite clasts and diamict matrix is consistent with fluvio-glacial deposition and extensive crazing of the granite substrate is suggestive of periglacial freeze–thaw activity (Figure 8f, g). In this circumstance it is possible that megaclast MC 6 was excavated as an ice-thrust (or cupola hill) of the type described by Aber and Ber (2007). The interpretation from Old Boolcoomata supports both glacial erosion and deposition.
Numerical modelling in support of a conceptual model for groundwater flow and geochemical evolution in the southern Outaouais Region, Quebec, Canada
Published in Canadian Water Resources Journal / Revue canadienne des ressources hydriques, 2018
Nelly Montcoudiol, John Molson, Jean-Michel Lemieux
Unconsolidated deposits left prior to the last glaciation have not been found in the study area, likely due to erosion by the many glacial–deglacial cycles during the Quaternary period (Daigneault et al. 2012). During the last glaciation, abrasion of the bedrock and ice movement deposited a discontinuous layer of till directly overlying the bedrock, while during the last deglaciation, freshwater fluvio-glacial sediments were deposited in the lower valleys. The Ottawa River valley (including lower reaches of secondary river valleys) was then invaded by the Champlain Sea about 12,000 years ago (Parent and Occhietti 1988), which left marine clays on top of the fluvio-glacial sediments (if they had not already been eroded). Due to isostatic rebound, the Champlain Sea progressively left the region about 10,000 years ago, leaving behind deltaic, littoral and pre-littoral sediments. Along the main rivers, this sequence is buried by ancient and more recent alluvium (Comeau et al. 2013).