Stratigraphic dating

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Changes between strata are interpreted as the result of fluctuations in the intensity and persistence of the depositional agent, e.g...... Stratigraphy is based on the law of superposition, which states that in a normal sequence of rock layers the youngest is on top and the oldest on the bottom. It is therefore possible to produce geological maps of the surface of a planet or satellite, and to form a stratigraphic classification to help to understand its history. Special mention should be made of spore and pollen analysis, which is used for determining the age of sedimentary strata in all subdivisions of the Phanerozoic.

Local sequences are studied, and after considering such factors as the average rate of deposition of the different rocks, their composition, the width and extent of the strata, the fossils contained, and the periods of uplift and erosion, the geological history of the sequence is reconstructed. Lunar stratigraphic systems include the Copernican, Imbrian, and Nectarian archaeology, the order in which cultural layers alternate relative to each other and to the underlying and overlying rocks and deposits. The paleontological method has been extensively employed throughout the Phanerozoic.

Stratigraphy is especially important in the study of settlements with a thick and, sometimes, greatly disturbed cultural layer—for example, primitive settlements, cities of the ancient East, Greek and Roman cities, and medieval cities. Arduino in 1759, is still used by non-Soviet geologists. Information on the radiometric age of sedimentary rocks is rather meager.

In such cases, each layer reflects a certain stage in the settlement’s or city’s history. In 1829, the term “Quaternary” was proposed by the French geologist J. The potassium-argon age method makes use of very rare potassium salts (carnallite) and glauconite, which is common in sedimentary rocks.

Chronology provides a temporal dimension that distinguishes archaeology, paleontology, and geology from the disciplines of ethnography and ethnology.

Stratigraphy was the basis for the creation of geologic maps and the geologic time scale. Some questions of the development of stratigraphy as a science were dealt with in the 17th century by the Danish scientist N. He was the first to clearly state the law of superposition of strata. The method was developed in the first half of the 19th century by the British scientists R. Other methods are also employed for correlating sedimentary and volcanogenic stratified formations. Geochemical analysis may be used to conduct a comparison with respect to the predominance of certain minerals or elements.The secondary rocks were thought to include interlayered basalts, which Werner thought formed by combustion of buried coal layers.The Scottish geologist James Hutton (1726-1797) argued that granite and basalt by solidification within the earth (as opposed to precipitating in from oceanwater).He would argue that these forces gave rise to mountains.Estimating age in the archaeological record is the primary step in understanding the human past.

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