Abstract

In Gotsu district, central part of Shimane Prefecture, highly weathered reddish plutonic rocks are developed. These reddish weathered crusts in part underlie the Plio-Pleistocene Tsunozu formation. Main mineral compositions of the reddish weathered crust are kaolin and vermiculitic mineral.Undoubtedly these reddish weathered materials must have been formed under much warmer climatic circumstances during late Pliocene judged from the stratigraphical relation of the weathered crust to the Tsunozu formation. Not only climatic condition and physiographic features but also chemical and physical properties of the rocks take part in the weathering processes.In this study, the writer proposes a “degree of the absolute chemical freshness” based on the following empirical formula:Degree of the absolute chemical freshnessFeO+MnO+MgO+CaO+Na2O+K2O/Al2O3+Fe2O3+H2O (+) (Weathered rock) /FeO+MnO+MgO+CaO+Na2O+K2O/Al2O3+Fe2O3+H2O (+) (Fresh rock)This formula is applicable to the applied geological works.

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 call

Disclaimer: 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.