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The AAPG/Datapages Combined Publications Database

AAPG Bulletin


Volume: 64 (1980)

Issue: 5. (May)

First Page: 690

Last Page: 690

Title: Burrow Patterns of Previous HitGhostNext Hit Crab Ocypode ceratophthalma (Pallas) as Possible Indicators of Foreshore Slopes: ABSTRACT

Author(s): A. Chakrabarti

Article Type: Meeting abstract


Burrow patterns of the Previous HitghostTop crab, Ocypode ceratophthalma (Pallas), collected in India from different types of beaches in different geomorphic settings, display a limited zonation whose seaward limit is the backshore-foreshore transition zone. Burrow forms whose initial direction of burrowing is shoreward include simple unbranched or multibranched types of J, U, and Y shapes.

Although the different subenvironments of a particular beach can be subdivided tentatively by the dominance of a particular form, similar subenvironments of beaches having different slopes and permeability of the beach surface register different types of burrows. In high sloped beaches, whether composed of quartz sand or carbonate skeletal sands, the upper part of the foreshore slope is mostly dominated by J, U, and Y forms, sometimes multibranched, and with relatively small burrow diameters. In flat beaches the region near the high water line is marked by large diameter, unbranched step-like burrows, and the U and Y shapes found in high sloped beaches are absent.

A uniformity in the asymptotic nature of the juncture of the secondary arm with the primary arm of Y burrows found in the upper part of the foreshore slope of high sloped beaches has been noted. A mathematical analogy between the shape of the secondary arm of these Y burrows with the streak line of water seepage caused by wave uprush and its successive movement of the saturated-unsaturated boundary under a pressure head due to the capillary action of the water table has been attempted.

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