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Inorganic Sediment Chemistry and Elemental Speciation
Published in Renato Baudo, John P. Giesy, Herbert Muntau, Sediments:, 2020
The study of dated sediment cores has proven particularly useful as it provides a historical record of the various influences on the aquatic system by indicating both the natural background levels and the man-induced accumulation of elements over an extended period of time. Marine and—in particular—lacustrine environments have the ideal conditions necessary for the incorporation and permanent fixing of metals and organic pollutants in sediments: reducing (anoxic) and nonturbulent environments, steady deposition, and the presence of suitable, fine-grained mineral particles for pollutant fixation. Various approaches to the dating of sedimentary profiles have been used, but the isotopic techniques, using 210Pb, 137Cs, and 239+240Pu, have produced the more unambiguous results and therefore have been the most successful (see review on “Historical Monitoring” by Alderton, 1985).
Design of axially loaded piles — Norwegian practice
Published in F. De Cock, C. Legrand, Design of Axially Loaded Piles European Practice, 2020
Arne Schram Simonsen, Corneliu Athanasiu
A typical soil profile above the marine limit may be described as follows: Top layer of organic matter, slide debris or other mixed materials.Alluvial gravels and sands.Lacustrine or sediments deposited in glacial lakes, mainly consisting of silts and sands.Moraines and/or glacifluvial sediments
Geology of Urban Watersheds
Published in Daniel T. Rogers, Urban Watersheds, 2020
Lacustrine sediments are lake deposits characterized by the presence of a range of fine-grained sediments in deep water to coarser-grained sediments in shallow water near the shoreline. Large lakes, such as the Great Lakes may have well defined and significant beach deposits composed of sand and gravel. In some arid regions, such as the southwestern portion of the United States, evaporation of lake water leaves behind evaporite deposits. Fine-grained lacustrine deposits tend to be thinly layered or stratified. Figure 2.39 is an example of a thinly layered lacustrine deposit.
Stratigraphy and vegetation signals from an upland, landslide-dammed, paleolake during the Last Glacial-Interglacial Transition, Waipaoa Sedimentary System, Hikurangi Margin, eastern North Island, New Zealand
Published in New Zealand Journal of Geology and Geophysics, 2022
Michael Marden, Katherine Holt, Matthew Ryan, Joe Carrasco, Kathleen Marsaglia, Matthew Kirby, Alan Palmer
In 2008, at Redpath 1A, excluding the topmost c. 3 m of alluvial sediments, sequential monoliths of the lacustrine sequence were collected using 9 × 50 × 3 cm U-shaped aluminium sleeves tamped into the outcrop then separated using a clay-cutting wire. The monoliths were wrapped in plastic and transported to Manaaki Whenua facilities in Gisborne where the Redpath 3 drill cores had been stored. The Redpath 1A monoliths and Redpath 3 cores were photographed and sedimentary structures, bedding characteristics, visual grain size, and diagenetic features were documented in greater detail by Carrasco (2012) to construct stratigraphic columns for each site (Appendices A1 and A2). The Redpath 3 cores had dried and shrunk during storage ultimately making correlations with the fresh Redpath 1A monoliths difficult. Coarser gravel was subsampled on the Redpath 1A trench face and mud smear-slide petrographic analyses were completed at California State University Northridge. Sub-samples of lacustrine sediments were collected at 1–2 cm intervals and subjected to mass magnetic susceptibility, water content, loss on ignition 550°C (percent total organic matter), and 950°C (percent total carbonate) analysis at California State University Fullerton (Appendices A3 and A4) following standard protocols for the laboratory (Dean 1974; Kirby et al. 2007).
Paleolimnological evidence of environmental change in Chinese lakes over the past two centuries
Published in Inland Waters, 2020
Ji Shen, Ke Zhang, Zhengwen Liu
Knowledge of the contamination of lake sediments by heavy metals is crucial because of their potential for biological toxicity, environmental longevity, and biological accumulation. In China, the problem has intensified rapidly as a result of urbanization and industrialization (Cheng et al. 2015), and recent studies concluded that virtually all lake sediments are contaminated to some degree (Shen et al. 2007, Xu et al. 2017a). Stratigraphic analyses of lacustrine sediments can be used to reconstruct temporal variations in natural and anthropogenic inputs of metals and other elements to the lake ecosystems, helping to establish reliable background concentrations for different elements, assess ecological risk, and formulate management and restoration strategies (Opfer et al. 2011, Zeng et al. 2014).
Environmental reconstruction and formation mechanisms for lacustrine source rocks of the third member of the Shahejie Formation in the Raoyang Sag, Bohai Bay Basin, eastern China
Published in Australian Journal of Earth Sciences, 2019
J. Yin, L. Guo, J. Meng, F. Hao, X. Chen, Y. Cao, H. Zou
Lacustrine source rocks are important hosts for significant petroleum resources and are commonly used to address questions about climate change and paleo-environment (e.g. Chen et al., 2010; Gonçalves, 2002; Hao, Zhou, Zhu, & Yang, 2011; Harris, Freeman, Pancost, White, & Mitchell, 2004; Katz, 1995; Song et al., 2013). Owing to the relatively small size of water reservoirs, lakes have higher rates of environmental change than marine systems (Gonçalves, 2002; Kelts, 1988), which may result in a wide variety of lacustrine source rock models for different lakes (Carroll & Bohacs, 2001; Diao et al., 2014; Gonçalves, 2002; Harris et al., 2004; Talbot, 1988; Widayat, Schootbrugge, Oschmann, Anggayana, & Püttmann, 2016). As the most important set of source rock interval in the Bohai Bay Basin, the third member of the Eocene Shahejie Formation (Es3) has been assessed in terms of paleolimnology in the Bozhong and Jiyang sub-basins (Hao et al., 2011; Ma et al., 2016; Tao, Wang, Zhen, & Zhi, 2001; Wang & Lin, 2012). The previous studies suggested that the overall climate was generally humid during the deposition of Es3 and arid during the deposition of the second member of the Shahejie Formation (Es2).