Lake Deposits

Lake Deposits

 

(also lacustrine deposits), sedimentary formations on the floor of modern lakes and of lakes that existed in previous geologic eras. Classified as continental deposits, they also possess features inherent to marine deposits, for example, good sorting of material and horizontal bedding. The distinguishing features of lake deposits are lenticularity, few remains of specific fauna, few remains of terrestrial plants and animals, and a close connection with alluvial and other types of continental sediments. Glaciolacustrine deposits are classified in a separate category.

Mechanical sediments accumulate in freshwater lakes, with fine-grained sediments having pronounced horizontal bedding often predominating; sapropel and diatomite are also common. As lakes become overgrown, they frequently turn into peat bogs. The character of lake deposits changes depending on the climate. In areas with a cold climate fragmental sandy-argillaceous material is deposited, sometimes with banded lamination. In lakes of the temperate zone, iron (bean ores), silica (diatomites), calcium carbonate, and organic matter (peat, sapropel) accumulate along with the fragmental material. In arid zones, where subsaline and saline lakes are found, carbonates, halite, and gypsum are deposited; in lakes without an outlet dolomite sediments and sometimes sodium carbonate are deposited.

In ancient sedimentary strata lake deposits consist of Devonian and Permian clays and marls, dolomites, and salt-bearing deposits.

References in periodicals archive ?
The road and port represent critical infrastructure to open up access to the Greenstone belts of the Slave Geological Province, which host MMG's Izok and High Lake deposits. The funding adds to the $7.25 milion already committed by Inuit Representative Group, Nunavut Tunngavik Inc (NTI).
The finding of a new oviraptorosaur species in the Nemegt Formation, which consists mostly of river and lake deposits, confirms that these dinosaurs were extremely well adapted to wet environments.
Though we have already found valley networks, deltas, and lake deposits that suggest sometime in the distant past, about four billion years ago, the Red Planet had water, nobody really knows about the conditions that prevailed back then.
To find out, an international team of scientists led out of the University of Copenhagen pulled nine cores of lake deposits from the Peace River drainage area in western Canada.
Mudstones discussed here include recent lake deposits in South America and Africa, modern and ancient lacustrine sediments, Jurassic terrestrial and Cambrian marine deposits, and diagenesis in ancient marine successions.
Now that we've arrived, we're seeing finely laminated mudstones in abundance." These silty layers in the strata are interpreted as ancient lake deposits.
* Bottom of the lake deposits: The bottom of the lake consists of sediments range from sand and clay and silt, but noted that the East Lake dominated by sand on the opposite west of the chaotic sludge.
Intriguingly, these new fossils were discovered in ancient river deposits, as opposed to the ancient lake deposits where feathered dinosaurs are often found in China.
This hole is located on the Andrew Lake fault which controls Areva's End and Andrew Lake deposits and recent discoveries by Cameco.
Phartiyal, B., Sharma, A., Srivastava, P., Ray, Y., 2009, Chronology of relict lake deposits in the Spiti River, NW Trans

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