Taphonomic processes in recent thanatocenoses at playa el pelícano, baja california
The northeastern coast of Baja California (Mexico) has extensive surface mollusk-shell deposits in exposed, semiprotected or protected sandy beaches. Waves, tides, currents and sediment transport influence the shell concentrations in the intertidal zone and control the morphology of these beaches....
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| Format: | Article |
| Language: | English |
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Universidad Autónoma de Baja California
2000-03-01
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| Series: | Ciencias Marinas |
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| Online Access: | https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/604 |
| Summary: | The northeastern coast of Baja California (Mexico) has extensive surface mollusk-shell deposits in exposed, semiprotected or protected sandy beaches. Waves, tides, currents and sediment transport influence the shell concentrations in the intertidal zone and control the morphology of these beaches. In order to evaluate the taphonomic processes involved in the formation of shell deposits in an exposed beach, we studied temporal changes in thanatocenoses of bivalves along 200 m of beach at spring tides in March, May and November 1993, and March and November 1994. Species were identified and their size, orientation (concave-up vs concave-down) and azimuth orientation of the anterior-posterior axis were measured. The assemblage was dominated by Glycymeris gigantea and included 15 common species. The shells showed a variable azimuth orientation, but with a trend parallel to the coastline, predominance of downward concavity and a polymodal size distribution with modes in 1 and 3 cm, in a size range of 0.3 to 8.5 cm. The taphonomic characteristics of these shell deposits may be useful in coastal paleoceanographic reconstructions.
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| ISSN: | 0185-3880 2395-9053 |