1 on 1 cams - Speleothem dating

Types of speleothems include Speleothems may also occur in lava tubes.

Although sometimes similar in appearance to speleothems in caves formed by dissolution, these are formed by the cooling of residual lava within the lava tube.

One of the main challenge of the technique is the correct identification of the radiation-induced centers and their great variety related to the nature and the variable concentration of the impurities present in the crystal lattice of the sample.

The term “speleothem” as first introduced by Moore (1952), is derived from the Greek words spēlaion "cave" théma "deposit". The vast majority of speleothems are calcareous, composed of calcium carbonate in the form of calcite or aragonite, or calcium sulphate in the form of gypsum.

Calcareous speleothems form via carbonate dissolution reactions.

Many factors impact the shape and color of speleothem formations including the rate and direction of water seepage, the amount of acid in the water, the temperature and humidity content of a cave, air currents, the above ground climate, the amount of annual rainfall and the density of the plant cover.

Most cave chemistry revolves around calcite; Ca CO.

Moreover, the radiation centers must be stable on geologic time, i.e., to have a very large lifetime, to make dating possible.

Many other artifacts, such as, e.g., surface defects induced by the grinding of the sample can also preclude a correct dating.

A particular strength of speleothems in this regard is their unique ability to be accurately dated over much of the late Quaternary period using the uranium-thorium dating technique.

Stalagmites are particularly useful for palaeoclimate applications because of their relatively simple geometry and because they contain several different climate records, such as oxygen and carbon isotopes and trace cations.

Only a few percents of the samples tested are in fact suitable for dating.

This makes the technique often disappointing for the experimentalists.

67-68 (1996), Levin and Munksgaard: Copenhagen Alexander, D 2000 ‘Excavation of Neolithic pits, later prehistoric structures and a Roman temporary camp along the line of the A96 Kintore and Blackburn Bypass, Aberdeenshire’, . Bennett, K D., Boreham, S., Sharp, M J and Switsur, V R 1992 ‘Holocene history of environment, vegetation, and human settlement in Catta Ness, Lunnasting, Shetland’, 105, 7-12.

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