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Basal gravel and sand mantling the bedrock floors of buried valleys throughout the Canadian Interior Plains, and conformably overlying proglacial lacustrine sediment, comprise the Empress Group. While previously conceptualized as stratigraphically equivalent deposits of preglacial rivers prior to the first and most extensive continental and montane glaciations, subsequent stratigraphic studies indicated that buried valley basal gravel must have been deposited between, or during, progressively more extensive continental glaciations and could not be stratigraphically equivalent throughout the buried valley network. However, in the general absence of formation-rank stratigraphic description of basal gravel units that might better inform the geologic history of the deposits, most workers simply consider Empress Group sediments time-transgressive. In this paper, we examine basal gravel at provincial and regional scales to understand its genesis and geologic history. At the provincial scale, we map basal gravel in three dimensions using a novel machine learning approach. At the regional scale, we formally define basal gravel formations at either end of the largest buried valley system in Alberta, which informs its glacial history and physiographic development and shows the importance of formation-rank stratigraphic description. Our results indicate that the buried valley network across Alberta is palimpsest in genesis and basal gravel units within it are chronostratigraphically intercalated between tills. We advocate that the Empress Group definition be extended across Alberta with modifications to improve its clarity and utility, and formally define the Old Fort, Unchaga, Ipiatik, and Winefred formations as part of the Empress Group. [ABSTRACT FROM AUTHOR]

Fluctuations in sea level influence the condition of coastal groundwater aquifers. In this paper the palaeo-hydrology of Anholt and part of Zealand and its dependence on the sea level history of Kattegat will be analyzed. The Late and Postglacial Sea-Level Changes in Kattegat are outlined and the consequences analyzed for Late and Postglacial ice movement and for two different coastal aquifers: a simple unconfined aquifer at the island Anholt, and a complex confined Limestone aquifers around Roskilde on Zealand. Data are presented which provide a description of how sea level changes have influenced and formed the island Anholt. This geological history can be used to provide information on the development of the salt-fresh groundwater interface under a sand island. The center of Anholt was covered by the sea at 6 ka and has now an ideal Ghyben-Herzberg freshwater lens. This means that the present equilibrium between the saltwater and freshwater has been established in less than 6000 years. Limestone aquifers on Zealand show no ideal Ghyben- Herzberg freshwater lens. Detailed 3-D mapping of a study area, around Roskilde- and Isefjord, has revealed how low sea-levels (around 50–30 ka) cause development of karst structures and deep erosion channels in the limestone (later filled with high permeable sand and gravel). These channels drain the groundwater to subsea springs, working as natural pumps, resulting in a freshwater "lens" much thinner than the equilibrium. [ABSTRACT FROM AUTHOR]

The paper presents information about the history of the Paldiski Northern Harbour, geotechnical characteristics of the bottom sediments, geology of the bedrock and environmental situation. Harbours of Paldiski are virtually ice-free, deep and well protected from the winds blowing from the open sea. Some 300-400 m west of the Paldiski Northern Harbour, the depth of the sea already reaches 20 m. The harbour was founded by Peter I, Czar of Russia, in 1718. During the Soviet occupation it was a closed naval port. After the retreat of Russian troops from Estonia in 1995, the sea floor and land area of the harbour were strongly polluted. For the time being the residual pollution has been liquidated. The extension of the harbour and large-scale construction works in the area are planned. Due to the variable thickness and changeable composition of the bottom deposits the engineering-geological conditions in the harbour area are complicated. [ABSTRACT FROM AUTHOR]