ISSN:
1365-3091
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Geosciences
Notes:
The Cape Fear Formation rests on basement rocks in the Cape Fear River valley of the North Carolina Coastal Plain. It consists primarily of graded muddy sand—sandy mud couplets. A typical sequence for each couplet starts with a disconformity, followed by a basal gravelly sand with megaclasts of quartz and clay pebbles, cross-bedded sand, and finally a structureless mud bed. Fossils are absent. The sand fraction is poorly sorted and the sediment has a clayey texture. Structures and textures suggest that each couplet is the product of a current waning from an upper flow regime, to the lower part of a lower flow regime. Turbidity current and fluvial origins are considered. Cross-bedding and textural criteria indicate that normal, low-density currents are responsible for at least part of the typical sequence. A normal fluvial origin is rendered less likely by the absence of mud cracking, root casts, and textural criteria of a partitioned subaerial environment. Stratigraphic and geochemical considerations suggest that the formation may have been deposited in estuaries or coastal lagoons; if so, the stratification may record sedimentation during the periodic flushing of saline water by river floods.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-3091.1968.tb00839.x
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