![]() Sinkholes also occur in sandstone and quartzite terrains.Īs the rock dissolves, spaces and caverns develop underground. Sinkholes are common where the rock below the land surface is limestone or other carbonate rock, salt beds, or in other soluble rocks, such as gypsum, that can be dissolved naturally by circulating ground water. In the case of exceptionally large sinkholes, such as the Minyé sinkhole in Papua New Guinea or Cedar Sink at Mammoth Cave National Park in Kentucky, an underground stream or river may be visible across its bottom flowing from one side to the other. Occasionally a sinkhole may exhibit a visible opening into a cave below. For example, groundwater may dissolve the carbonate cement holding the sandstone particles together and then carry away the lax particles, gradually forming a void. Sinkholes often form through the process of suffosion. The formation of sinkholes involves natural processes of erosion or gradual removal of slightly soluble bedrock (such as limestone) by percolating water, the collapse of a cave roof, or a lowering of the water table. These caves may drain into tributaries of larger rivers. Sinkholes that capture drainage can hold it in large limestone caves. Sinkholes may capture surface drainage from running or standing water, but may also form in high and dry places in specific locations. Formation Sinkholes near the Dead Sea, formed when underground salt is dissolved by freshwater intrusion, due to continuing sea-level drop. Sinkholes may form gradually or suddenly, and are found worldwide. Sinkholes are usually circular and vary in size from tens to hundreds of meters both in diameter and depth, and vary in form from soil-lined bowls to bedrock-edged chasms. ![]() Most sinkholes are caused by karst processes – the chemical dissolution of carbonate rocks, collapse or suffosion processes. Sink and stream sink are more general terms for sites that drain surface water, possibly by infiltration into sediment or crumbled rock. A cenote is a type of sinkhole that exposes groundwater underneath. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as vrtače and shakeholes, and to openings where surface water enters into underground passages known as ponor, swallow hole or swallet. ![]() For other meanings, see Doline (disambiguation).Ī sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. Part of this network of monitoring stations will be available also to future projects."Doline" redirects here. This included the lowest meteorological monitoring station in the world at 429 m below sea level. For this purpose, the scientists conducted long-term monitoring and intensive measurement campaigns at more than 150 locations around the Dead Sea. We were only able to address them in an interdisciplinary approach together with partners from the countries bordering on the Dead Sea." The objective was to document the scientific state of the art as a basis for future decisions and environmental policy. "The three major challenges water availability, climate change, and environmental risks were in the focus of our work. "Reliable data are a precondition to understanding these environmental processes – and thus to the development of prediction models allowing, for instance, forecasts of evaporation and water availability, but also risk assessments and warning systems," explains Professor Christoph Kottmeier, KIT meteorologist and spokesman of DESERVE. The meteorological, hydrological, and geophysical processes and their interactions underlying these phenomena were studied for five years by scientists of the Karlsruhe Institute of Technology (KIT), the GFZ – Deutsches GeoForschungs-Zentrum Potsdam, and the Helmholtz-Zentrum für Umweltforschung (UFZ) in Leipzig within the DESERVE Helmholtz Virtual Institute together with local partners (DESERVE stands for "DEad SEa Research VEnue"). Besides the lake level decline there are environmental risks such as desertification, pollution of drinking water by brine, flash floods, sinkholes and earthquakes. The region constitutes an "open-air laboratory" for climatologists and environmental scientists as well as geoscientists. The Dead Sea extends over 90 km in the north-south direction in an unique scenery of desert, semi-desert and oases – more than 400 m below the sea level at the lowest land site on earth.
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