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In pollen dating geological happenings

in pollen dating geological happenings-61

Thus, Sir Arthur Evans was able to establish an accurate absolute chronology for the ancient civilizations of Crete and Greece through the use of Egyptian trade objects that appeared in his excavations—a technique known as cross-dating.In dendrochronology, the age of wood can be determined through the counting of the number of annual rings in its cross section.

in pollen dating geological happenings-86

In absolute or chronometric dating, the investigator establishes the age of an object or event in calendar years.The method begins with the careful drawing and description of strata (the geological or archaeological profile).The profile from one location is then compared with profiles from surrounding sites.With the decipherment of the Egyptian hieroglyphics, Egyptologists had access to such an absolute timescale, and the age, in calender years, of the Egyptian dynasties could be established.Furthermore, Egyptian trade wares were used as a basis for establishing the age of the relative chronologies developed for adjoining regions, such as Palestine and Greece.Stratigraphic dating assumes that the lower layers in any particular profile are older than the upper layers in that profile ( "the law of superposition" ) and that an object cannot be older than the materials of which it is composed.

Igneous masses are dated according to whether they caused metamorphism in the surrounding rock (proof of emplacement in preexisting rock) or whether sediments were deposited on them after they were formed.

After 1950, the physical sciences contributed a number of absolute dating techniques that had a revolutionary effect on archaeology and geology.

These techniques are based upon the measurement of radioactive processes (radiocarbon; potassium-argon, uranium-lead, thorium-lead, etc.; fission track; thermoluminescence; optically stimulated luminescence; and electron-spin resonance), chemical processes (amino-acid racemization and obsidian hydration), and the magnetic properties of igneous material, baked clay, and sedimentary deposits (paleomagnetism).

Through the investigation of many different stratigraphic contexts, a master sequence of fossil and floral assemblages may be devised for a region.

Absolute Dating Absolute dating can be achieved through the use of historical records and through the analysis of biological and geological patterns resulting from annual climatic variations, such as tree rings (dendrochronology) and varve analysis.

According to this system, humans passed through three distinct stages of technological development, based on the primary material used to manufacture tools and weapons: the Stone Age, the Bronze Age, and the Iron Age.