Skip to main content

assimilation-fractional crystallization

assimilation-fractional crystallization (AFC) An important process in igneous petrology whereby melts with widely differing isotopic and trace elements can be produced. When a primitive magma, such as a basalt, invades crustal rocks, portions of the country rock may become detached and included in the magma as xenoliths. Because of the high temperature and thermal capacity of the basalt, it is capable of melting a proportion of the country rock. In doing so it loses some of its own heat and thus a proportion of the magma crystallizes. The composition of the resulting magma is determined by the relative amounts of magma and country rock initially present; the rates at which assimilation and crystallization proceed; and by the partition coefficients of the various elements between solid and liquid.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"assimilation-fractional crystallization." A Dictionary of Earth Sciences. . 23 Apr. 2019 <>.

"assimilation-fractional crystallization." A Dictionary of Earth Sciences. . (April 23, 2019).

"assimilation-fractional crystallization." A Dictionary of Earth Sciences. . Retrieved April 23, 2019 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.