Hammett Shale

The Hammett Shale is a geologic formation in Texas. It preserves fossils dating back to the Cretaceous period.

Hammett Shale
Stratigraphic range: Aptian ~120–112 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Formation
Location
Region	Texas
Country	United States

Trinity Group stratigraphic column in Texas

A stratigraphic column at the Mount Bonnell Fault location starts with the Lower Cretaceous Trinity Group overlain by the Edwards Group. Upper Cretaceous formations follow, starting with the Del Rio Clay, Buda Limestone, and then the Eagle Ford Group. Formations within the Trinity Group include the Hammett Formation, Cow Creek Formation, Hensel Formation, and Lower and Upper Glen Rose Formation. The Hammett and the lower portion of the Upper Glen Rose act as confining units (or aquitard) for the Middle Trinity Aquifer.^[1]

See also

• List of fossiliferous stratigraphic units in Texas
• Paleontology in Texas