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Construction Methodology of Dam Foundation and Technology of Its Foundation Treatment
Published in Suchintya Kumar Sur, A Practical Guide to Construction of Hydropower Facilities, 2019
Caves are splendid for their crystal formations on their ceilings, walls and floors, which are known as speleothems. The excess calcium gets deposited on the ceiling, floor and wall of the cave, creating a unique formation known as speleothems. It is the crystallized form of the mineral calcite. The acidic water seeps through fissures/cracks and dissolves some limestone, and when it reaches the cave it loses some carbon dioxide to cave air. The water is now less acidic and unable to hold the same amount of limestone and the tiny crystals are deposited and slowly decorate the cave with speleothems.
The management of karst environments
Published in David Drew, Heinz Hötzl, Karst Hydrogeology and Human Activities, 2017
In Phase 2 the high sediment load of the flood water may lead to a plugging of swallow holes and filling up of the small openings. This can cause a significant drop in the ground water table elevation. In respect of the chemical composition of the underground water, an additional increase of total dissolved calcium carbonate will take place and due to changing saturation conditions precipitation of solutes will lead to sinter (speleothem) formation.
Microorganisms and the natural heritage of Dinaric karst—a review
Published in Cesareo Saiz-Jimenez, The Conservation of Subterranean Cultural Heritage, 2014
Algae and cyanobacteria are not considered typical cave microbiota, but they can survive in cave waters and subaerophytic habitats. Their communities are often found around cave entrances and can contribute to speleothem formation through carbonate precipitation, as recently demonstrated in Škocjanske jame (Slovenia) (Mulec et al. 2007).
Improving Australia’s flood record for planning purposes – can we do better?
Published in Australasian Journal of Water Resources, 2020
KJ Allen, P Hope, D Lam, JR Brown, RJ Wasson
Speleothems are formations in caves – stalactites or stalagmites – formed by the deposits of minerals from dripping water. They are ideal for the reconstruction of terrestrial hydroclimate (Lachniet 2009). Typically, three tools are used: δ18O, luminescent bands (Shen et al. 2013) and physical deposition of detritus from cave flooding (Denniston et al. 2015; Denniston and Luetscher 2017). In Australia, speleothem-based flood records from north-western Australia, tropical Queensland and South Australia exist. Importantly, Denniston et al. (2015) found that a sharp increase in extreme rainfall events from ~1890 co-occurred with the expansion of grazing, highlighting the need to consider anthropogenic land-use changes when interpreting records.