Taphonomic Rules - Vertebrates


• Information loss in terrestrial environments is largely the result of transport, disarticulation, sorting, and breakage by water, predators, scavengers, and trampling.

Vertebrate biostratinomy
• Disarticulation
• Weathering
– Behrensmeyer’s stages of weathering

Vertebrate biostratinomy
• Transport - fluvial systems
• Input
– Direct
– Overland
– Reworking
• Important Depositional Environments
– Channel lag, channel fill, flood plain

Vertebrate biostratinomy
• Susceptibility to transport
• Important factors
– Bone size, shape, and density

Vertebrate biostratinomy
• Particle entrainment by fluids - the basics
• Why do bones move in currents?
• Critical threshold - fluid velocity and viscosity, and size, shape, and density
• Forces - drag and lift

Meandering Streams
-> velocity greatest on outside of bend = erosion: cutbank

-> velocity is less on inside of bend= deposition: point bar

Vertebrate taphonomic models
• Important Depositional Environments
– Channel lag, channel fill, flood plain
• What other environments are there?
– Traps
– Caches
– Caves

Vertebrate Biostratinomy
• These bone accumulated in point bar facies of a stream deposit…
• With the people next to you discuss the following:
• Does this deposit represent a catastrophic or attritional deposit?

Vertebrate Taphonomic Models
• How did the bones get here?
• Types of Occurrence
– Interpreted from biostratinomic features

Vertebrate Taphonomic Models
• Taphonomic pathways
• Environments - hydraulic concentration

Vertebrate Taphonomic Models
• Sedimentologic and biostratinomic comparisons