Comparative taphonomy and faunal composition of shelly cheniers from northeastern Baja California, Mexico

Taphofacies analysis of 4334 shells of Mulinia coloradoensis described by nine variables indicated that the shells accumulated in these cheniers are rarely affected by biological processes and moderately affected by physical processes. The shells collected from the chenier surface have poorer preservation than the subsurface ones, indicating that taphonomic degradation is mostly a surface phenomenon. Multivariate analyses discriminate the chenier generations even when the poorly preservable luster variables are excluded from the analysis. Chenier shelly assemblages are taphonomically distinct from assemblages formed in other marine environments. They are characterized by a very low intensity of bioerosion and encrustation. -from Authors