Why deposits of longitudinal dunes are rarely recognized in the geologic record
Dunes that are morphologically of linear type, many of which are probably of longitudinal type in a morphodynamic sense, are common in modern deserts, but their deposits are rarely identified in aeolian sandstones. One reason for non-recognition of such dunes is that they can migrate laterally when they are not exactly parallel to the long-term sand-transport direction, thereby depositing cross-strata that have unimodal cross-bed dip directions and consequently resemble deposits of transverse dunes. Dune-parallel components of sand transport can be recognized in ancient aeolian sands by examining compound cross-bedding formed by small dunes that migrated across the lee slopes of large dunes and documenting that the small dunes migrated with a component in a preferred along-crest direction over the large dunes.
Citation Information
Publication Year | 1985 |
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Title | Why deposits of longitudinal dunes are rarely recognized in the geologic record |
DOI | 10.1111/j.1365-3091.1985.tb00498.x |
Authors | David M. Rubin, Ralph E. Hunter |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Sedimentology |
Index ID | 70135813 |
Record Source | USGS Publications Warehouse |
USGS Organization | Coastal and Marine Geology Program |