The formation is composed of
sands,
clays and
carbonates which are interbedded. The sands are light gray to olive gray and poorly consolidated. They are clay-like with some
dolomite with a very fine to medium grained
phosphate component. Carbonates are usually light gray to yellowish dolomite found in
outcroppings. The dolomites are soft to hard with variably sandy, clay-like, phosphate components with
opaline chert often found. The phosphate content is high enough to warrant mining. Three sequences of sediment deposition were defined in 1998. Five
lithofacies were identified in 2000 (upper part of the formation). •
Diatomaceous mudstone •
Terrigenous mudstone • Clay-rich quartz sand •
Quartz sand •
Pelecypod-rich quartz sand or
sandstone Fossils •
Mollusks occur as reworked casts, molds, and limited original shell material. • Vertebrate fossils • Shark's teeth • Silicified corals and wood ==Members==