Asymmetrical ripple marks and the origin of water-laid Cosets of Cross-Strata

Autor: J. R. L. Allen
Rok vydání: 2007
Předmět:
Zdroj: Geological Journal. 3:187-236
ISSN: 1099-1034
0072-1050
DOI: 10.1002/gj.3350030201
Popis: Asymmetrical ripple marks formed by flowing water are described and classified on geometrical form, physical size, and hydrodynamic conditions of origin. By analysing models it is demonstrated that the character of cosets of cross-strata resulting from the migration of asymmetrical ripple marks is dependent on ripple geometry and sediment supply. Predicted cross-stratification patterns are shown to agree well with those described from water-laid sediments. The use of cross-strata in deducing sedimentation rates and depths of deposition is pointed out. Models are developed from natural situations for interpreting cross-stratal dip direction patterns in shallow marine and deltaic sediments.
Databáze: OpenAIRE