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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. 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 ...

  4. 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.

  5. 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.

  6. Geochronology - Wikipedia

    en.wikipedia.org/wiki/Geochronology

    Often applied to the trace mineral zircon in igneous rocks, this method is one of the two most commonly used (along with argon–argon dating) for geologic dating. Monazite geochronology is another example of U–Pb dating, employed for dating metamorphism in particular. Uranium–lead dating is applied to samples older than about 1 million years.

  7. Chronological dating - Wikipedia

    en.wikipedia.org/wiki/Chronological_dating

    For a non-exhaustive list of relative dating methods and relative dating applications used in geology, paleontology or archaeology, see the following: Cross-cutting relationships; Fluorine absorption dating; Harris matrix; Law of included fragments; Law of superposition; Lichenometry; Marine isotope stages, based on the oxygen isotope ratio cycle

  8. Chronostratigraphy - Wikipedia

    en.wikipedia.org/wiki/Chronostratigraphy

    Chronostratigraphy is the branch of stratigraphy that studies the ages of rock strata in relation to time.. The ultimate aim of chronostratigraphy is to arrange the sequence of deposition and the time of deposition of all rocks within a geological region, and eventually, the entire geologic record of the Earth.

  9. Rubidium–strontium dating - Wikipedia

    en.wikipedia.org/wiki/Rubidium–strontium_dating

    The rubidium–strontium dating method (Rb–Sr) is a radiometric dating technique, used by scientists to determine the age of rocks and minerals from their content of specific isotopes of rubidium (87 Rb) and strontium (87 Sr, 86 Sr). One of the two naturally occurring isotopes of rubidium, 87 Rb, decays to 87 Sr with a half-life of 49.23 ...