Palm Beach Road Cut
The road cut is located on Country Club Road on Palm Beach Island. It extends for 600 feet in and east-west direction, with walls standing 200 feet high on both sides. The rock on the east end is granular coquina, grading into fine-grained shell hash towards the west. Avalanche cross-bedding striking north-south and dipping 30° to the west is present at the east end of the road cut. At the center of the cut the bedding undulates between the westward dip and the horizontal. A scour-and-fill structure also contains avalanche cross-bedding, dipping 26° to the west. The scour-and-fill truncates the bedding beneath it. Small burrows are present in the rock. Tubular structures at the top of the outcrop have been interpreted as both root casts and large burrows. Perkins (1977) believes this outcrop is a barrier beach deposit on the west side, and a dune deposit on the east side, separated by a disconformity marked by a paleosoil. Parker (1955) calls this surface an unconformity.
Photos by Dr. Anton Oleinik
Lamination |
Avalanche cross-beds |
Small burrows on the upper surface of the rock
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