Skip to main content

silica saturation

silica saturation The concentration of silica (SiO2) in an igneous rock, relative to the concentration of other chemical constituents in the rock which combine with the silica to form silicate minerals. On this basis, three classes of igneous rock are recognized: (a) silica-oversaturated rocks (e.g. granite), in which there is more than enough silica to satisfy the requirements of all the major silicate minerals, the free silica appearing as quartz in the rock; (b) silica-saturated rocks (e.g. diorite), in which there is just enough silica present to satisfy the requirements of all the major silicate minerals, there being neither an excess nor deficiency of silica, resulting in a lack of both quartz and feldspathoid minerals in the rock; and (c) silica-undersaturated rocks (e.g. nepheline syenite), in which there is not enough silica present to satisfy the requirements of all the major silicate minerals, the silica deficiency being accommodated by the crystallization of feldspathoids (nepheline, leucite) in place of feldspar, the feldspathoids containing less silica in their structure than feldspars.

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

  • MLA
  • Chicago
  • APA

"silica saturation." A Dictionary of Earth Sciences. . Encyclopedia.com. 15 Nov. 2018 <https://www.encyclopedia.com>.

"silica saturation." A Dictionary of Earth Sciences. . Encyclopedia.com. (November 15, 2018). https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/silica-saturation

"silica saturation." A Dictionary of Earth Sciences. . Retrieved November 15, 2018 from Encyclopedia.com: https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/silica-saturation

Learn more about citation styles

Citation styles

Encyclopedia.com 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, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com 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

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com 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.