Abstract by Brandon Theurer
Triassic Period CSI—A taphonomic study of 80+ sphenosuchians from the Saints and Sinners Quarry in northeastern Utah
The Saints & Sinners Quarry in northeastern Utah is remarkable for its diverse and significant Late Triassic fossils from an interdunal lake. Besides the Triassic pterosaur, Caelestiventus, eight other taxa are represented at the site. The most abundant taxon is a new type of sphenosuchian, a small crocodylomorph. Based on femoral lengths, which range from 14 mm to 69 mm, these sphenosuchians range in size from 120 to 250 mm long. The sheer number of these crocodylomorphs preserved at the site is startling, with well over 80 individuals, over 30 of which have at least some degree of articulation. Such amazing preservation begged for a taphonomic study. The specimens are concentrated at the boundary between the middle and lower rock layers and the articulated ones are buried belly-down with a roughly north-south orientation. Very soon after death, the bodies of the crocodylomorphs were aligned by wave action in shallow, near-shore waters where they were buried in two discreet sandstorms by sand from dunes along the shoreline.