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  2. Relative dating - Wikipedia

    en.wikipedia.org/wiki/Relative_dating

    Relative dating by biostratigraphy is the preferred method in paleontology and is, in some respects, more accurate. [1] The Law of Superposition, which states that older layers will be deeper in a site than more recent layers, was the summary outcome of 'relative dating' as observed in geology from the 17th century to the early 20th century.

  3. Chronological dating - Wikipedia

    en.wikipedia.org/wiki/Chronological_dating

    This usually requires what is commonly known as a "dating method". Several dating methods exist, depending on different criteria and techniques, and some very well known examples of disciplines using such techniques are, for example, history, archaeology, geology, paleontology, astronomy and even forensic science, since in the latter it is ...

  4. Geologic time scale - Wikipedia

    en.wikipedia.org/wiki/Geologic_time_scale

    Geochronology is the scientific branch of geology that aims to determine the age of rocks, fossils, and sediments either through absolute (e.g., radiometric dating) or relative means (e.g., stratigraphic position, paleomagnetism, stable isotope ratios). Geochronometry is the field of geochronology that numerically quantifies geologic time. [16]

  5. Law of included fragments - Wikipedia

    en.wikipedia.org/wiki/Law_of_included_fragments

    The law of included fragments is a method of relative dating in geology.Essentially, this law states that clasts in a rock are older than the rock itself. [1] One example of this is a xenolith, which is a fragment of country rock that fell into passing magma as a result of stoping.

  6. Geochronology - Wikipedia

    en.wikipedia.org/wiki/Geochronology

    [2] [3] [4] Two or more radiometric methods can be used in concert to achieve more robust results. [5] Most radiometric methods are suitable for geological time only, but some such as the radiocarbon method and the 40 Ar/ 39 Ar dating method can be extended into the time of early human life [6] and into recorded history. [7]

  7. Principle of original horizontality - Wikipedia

    en.wikipedia.org/wiki/Principle_of_original...

    It is a relative dating technique. The principle is important to the analysis of folded and tilted strata. It was first proposed by the Danish geological pioneer Nicholas Steno (1638–1686). The Permian through Jurassic stratigraphy of the Colorado Plateau area of southeastern Utah is a great example of Original Horizontality.

  8. Lichenometry - Wikipedia

    en.wikipedia.org/wiki/Lichenometry

    Several methods exist for dating surfaces with help of lichenometry; the most simple relies on a single largest lichen though other methods use more. There are also differences in the way the lichen is measured; some scientists suggest that the largest diameter should be measured, but others prefer the diameter of the largest inscribed circle.

  9. Cross-cutting relationships - Wikipedia

    en.wikipedia.org/wiki/Cross-cutting_relationships

    Cross-cutting relationships can be used to determine the relative ages of rock strata and other structures. Explanations: A – folded rock strata cut by a thrust fault; B – large intrusion (cutting through A); C – erosional angular unconformity (cutting off A & B) on which rock strata were deposited; D – volcanic dike (cutting through A, B & C); E – even younger rock strata (overlying ...