TAPHONOMY AND DEPOSITIONAL SETTING OF THE BURGESS SHALE TULIP BEDS, MOUNT STEPHEN, BRITISH COLUMBIA

Abstract

ABSTRACT Burgess Shale–type deposits represent exceptional preservational windows for examining the biodiversity and ecological structure of some of the earliest metazoan communities that evolved during the Cambrian Explosion. While much attention has been paid to the original Burgess Shale locality, the Walcott Quarry on Fossil Ridge, temporal and regional variations of the depositional environment of the Burgess Shale biota as a whole are still poorly understood. Here we present the first comprehensive taphonomic and sedimentological study of the Tulip Beds on Mount Stephen (Campsite Cliff Shale Member, Burgess Shale Formation), based on a time-averaged assemblage of nearly 10,000 specimens. The taphonomic characteristics—size sorting, resistance to decay, and potential flow alignment—and mode of deposition of this assemblage are compared specifically to those of the nearby and stratigraphically younger Walcott Quarry assemblage. Like other Burgess Shale–type deposits, the Tulip Beds consist of millimet...