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Nature of soil and rock
Published in Hsai-Yang Fang, John L. Daniels, Introductory Geotechnical Engineering, 2017
Hsai-Yang Fang, John L. Daniels
Lacustrine deposits (marls and tufa): Lacustrine deposits are confined to those sediments laid down in lakes and streams associated with glacier or the pleistocene epoch (1.8 million to 8000 years ago). It also includes those sediments deposited in lake basins or in valleys occupied by streams. Lake sediments consists of marls, tufa, clays, silts, sand gravel, iron hydroxides (Fe(OH)2), iron carbonate (Fe(CO3)2), silicon dioxide (SiO2), manganese oxide (MnO2), calcium phosphate (Ca(PO4)), organic matter, and evaporites. Lake marls are a mixture rich in calcium carbonate (CaCO3) content with various impurities that impart an array of colors. Most are gray to white or pale blue but red and black marls are not uncommon. Tufa is a limestone deposit that is more or less porous and banded.
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.
Intercept Trench Technology For Remediating Waste Oil Contaminated Soil And Groundwater
Published in Bell John W., Proceedings of the 44th Industrial Waste Conference May 9, 10, 11, 1989, 1990
David A. Piotrowski, Karl W. Yost
The geology in the region of the site consists predominantly of Pleistocene, Wisconsinan age glacial deposits.1 The glacial materials surrounding the site were likely deposited as a result of mass ice melting resulting in morainal till deposits and intermorainal or lake plain lacustrine deposits. The morainal soil in the region is chiefly composed of clay rich till materials with occasional sand or silt rich layers and lenses. The intermorainal/lacustrine deposits consist mostly of silt and clay formations with occasional peat beds.
Synergistic impacts of climate change and human activities on spatiotemporal organic nitrogen burial variation in a plateau lake in southwest China
Published in Inland Waters, 2023
Tao Huang, Yang Luo, Quanliang Jiang, Zhigang Zhang, Hao Yang, Changchun Huang
Nitrogen is a limiting factor for the primary production of ecosystems and has become a major topic in climate change research over the past few decades (Galloway et al. 2008, Fowler et al. 2013). Lacustrine deposits play a vital role in overall nutrient cycling in lake ecosystems, especially regarding the nitrogen (N) cycle (Elser et al. 2007, Conley et al. 2009). Lacustrine N has many forms with different biogeochemical characteristics. Sedimentary organic nitrogen (ON), the main form of N (Zolitschka et al. 2015, Huang et al. 2017b), accumulates in the sediment and is easily converted to ammonium (NH4+), nitrite (NO2−), and nitrate (NO3−) via mineralization and nitrification (Wu et al. 2019, Wong et al. 2021). A part of the converted NH4+ and NO3− can be released into the overlying water, which may cause algal blooms (Galman et al. 2008, Yu et al. 2018). The effects of algal residues, considered important autochthonous sources, on organic matter (OM) burial have been widely studied (Anderson et al. 2014, Leithold et al. 2016). While carbon is a major element in OM and has been widely reported, research concerning N is limited (Anderson et al. 2013, Jiang et al. 2020).