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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. Chronological dating - Wikipedia

    en.wikipedia.org/wiki/Chronological_dating

    Palynology, the study of modern-dated pollens for the relative dating of archaeological strata, also used in forensic palynology. Paleomagnetism; Paleopalynology, also spelt "Palaeopalynology", the study of fossilized pollens for the relative dating of geological strata. Principle of original horizontality; Principle of lateral continuity

  7. 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.

  8. Principle of faunal succession - Wikipedia

    en.wikipedia.org/wiki/Principle_of_faunal_succession

    A fossilized Neanderthal bone (less than 500,000 years old) will never be found in the same stratum as a fossilized Megalosaurus (about 160 million years old), for example, because neanderthals and megalosaurs lived during different geological periods, separated by millions of years. This allows for strata to be identified and dated by the ...

  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 ...