Contribution
Lithostratigraphy: Formation of the Formation
Pratt, Brian R.; Finney, Stanley C.; Easton, R. Michael; Piller, Werner E.
Newsletters on Stratigraphy Volume 56 Number 3 (2023), p. 307 - 330
87 références bibliographiques
publié: Jun 12, 2023
publication en ligne: Oct 7, 2022
manuscrit accepté: Aug 8, 2022
revision du manuscrit reçu: Jul 27, 2022
révision du manuscrit demandée: Jun 17, 2022
manuscrit reçu: Apr 19, 2022
ArtNo. ESP026005603001, Prix: 29.00 €
Abstract
Lithostratigraphy has traditionally dealt with the nomenclature of well-preserved and weakly metamorphosed sedimentary rocks. Lithodemic stratigraphy has been established for igneous plutonic and more strongly metamorphosed rocks. Allostratigraphy is based on unconformity-bounded stratigraphic units. All three have formally defined classification schemes with the fundamental units being Formation, Lithodeme and Alloformation, respectively. Definition, formal requirements and procedures for establishing units are described here. Although lithostratigraphy is the most descriptive and objective branch in stratigraphy, various phenomena may cause difficulties in description and reconstruction and selected case studies are described. They include ‘layer-cake’ geology, lateral facies changes and complex geometries, spatially widely distributed units and different national approaches, mappable bodies due to alteration, imbricate thrust sheets, plutonic igneous rocks, igneous and metamorphic rocks, high metamorphic grade terrane, and an allostratigraphic example from the Cretaceous. Different approaches for non-marine Quaternary sediment bodies are noted.
Mots-clefs
Stratigraphy • lithostratigraphy • lithodemic stratigraphy • allostratigraphy