Hammett Shale

Last updated
Hammett Shale
Stratigraphic range: Aptian
~120–112  Ma
Type Formation
Location
Region Texas
CountryFlag of the United States.svg  United States
Trinity Group stratigraphic column in Texas Austin Chalk stratigraphic column in Texas.png
Trinity Group stratigraphic column in Texas

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

Contents

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

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References

  1. Saribudak, Mustafa (September 2016). "Geophysical mapping of Mount Bonnell fault of Balcones fault zone and its implications on Trinity-Edwards Aquifer interconnection, central Texas, USA". The Leading Edge. Society of Exploration Geophysicists. 35 (9): 752–758. doi:10.1190/tle35090752.1 . Retrieved 12 September 2016.