Abstract
The of igneous rocks (F = Fe2O3:FeO) depends on the partial pressure of oxygen during crystallization and therefore, in part, on depth of crystallization. For this reason F increases in the order: deep intrusives, dike rocks, extrusives, pyroclastics. Also, in general, F increases with increasing silica content, although there are exceptions. As it is not always easy to distinguish intrusive rocks from extrusive ones, or extrusives from pyroclastics, it is proposed that the oxidation ratio be used as a criterion of fades of igneous rocks. --F. E. Ingersoll.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
