NACSN, note 67--Application for revision of Articles 36 and 37, Lithodemic units of the North American stratigraphic code

Robert M. Easton; Lucy E. Edwards; Randall C. Orndorff; Manuel Duguet; Ismael Ferrusquia-Villafranca

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NACSN, note 67--Application for revision of Articles 36 and 37, Lithodemic units of the North American stratigraphic code

Robert M. Easton·Lucy E. Edwards·Randall C. Orndorff·Manuel Duguet·Ismael Ferrusquia-Villafranca

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Abstract

Currently the North American Stratigraphic Code, (NACSN 2005, Article 37) sets restrictions on the use of the term “complex” for lithodemic units. With exceptions for “volcanic complex” and “structural complex,” a complex must consist of more than one genetic class of rock (i.e., sedimentary, igneous or metamorphic). Thus, the use of the term “complex” to describe masses of intrusive rocks is not allowed. Asimilar restriction is also included in a recent British Geological Survey proposal for using lithodemic units to classify igneous rocks (Gillespie et al. 2008).Currently the North American Stratigraphic Code, (NACSN 2005, Article 37) sets restrictions on the use of the term “complex” for lithodemic units. With exceptions for “volcanic complex” and “structural complex,” a complex must consist of more than one genetic class of rock (i.e., sedimentary, igneous or metamorphic). Thus, the use of the term “complex” to describe masses of intrusive rocks is not allowed. Asimilar restriction is also included in a recent British Geological Survey proposal for using lithodemic units to classify igneous rocks (Gillespie et al. 2008).

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Robert M. Easton, Lucy E. Edwards, Randall C. Orndorff, Manuel Duguet, Ismael Ferrusquia-Villafranca. 2015. NACSN, note 67--Application for revision of Articles 36 and 37, Lithodemic units of the North American stratigraphic code. https://pubs.usgs.gov/publication/70156790

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