FAILED GYROLITHES BURROWS: A SEDIMENTOLOGICAL DILEMMA?

Gyrolithes texanus is a helical burrow found in the Cretaceous carbonate chalks of Central Texas. Often identifiable by its glauconized walls, this trace fossil is found in association with Ophiomorpha and Thalassinoides burrows throughout the Austin Chalk Formation. Recent study of an exposure containing these ichnofossils has produced several instances which display abandoned Gyrolithes burrow construction. The causes of burrow failure in soft sediments are many, but it is not immediately apparent what prevented burrow completion among the observed traces. This study compares the observed traces with possible reasons for abandonment, especially within the context of initial burrow construction.