The white limy beds are interbedded with thin brown coarse conglomerate deposits, with clasts containing a variety of rocks with the exception of basalts. While most of the beds in the chalk canyon formation are a white amorphous and thickly bedded sequence of tuffaceous rocks, there are also many areas with finely bedded laminar beds of very finely grained sediments with sedimentary structures. Most common are mudcracks. Most are in the range of 1 inch cell size. Along with mudcracks, crossbedding, channel fill deposits, and raindrop impressions were seen.
Fossils are rare.
Most abundant are highly bioturbated worm burrow slabs, with small tubular burrows about 2 to 5mm across saturating the surfaces of localized areas. This is the only fossils mentioned in the literature. But we also found other types of trace fossils including Aulichinites - attributed to small gastropods grazing traces, and a few vertebrate toe and foot imprints similar in size to a small carnivore type animal might produce. Its key to note that any areas with mudcracks always indicates a period of subareal exposure, and the possibility of animals leaving traces is always present. One body fossil of a small annelid worm was also found, similar if not identical to Deros sp., a small tube building worm, that lived on rotting vegetation in lakes and streams as today.