Glens Falls Formation

Glens Falls

Stratigraphic range:
TypeFormation
Unit ofTrenton Group
Sub-units
  • Shoreham Member
  • Larrabee Member
  • Montreal Member
OverliesAmsterdam Limestone
Lithology
PrimaryLimestone
OtherShale
Location
RegionNew York, Ontario
CountryUnited States, Canada
Type section
Named forGlens Falls, NY
Named by(RUEDEMANN, 1912)

The Glens Falls formation is a unit of the Trenton Group. The Glens Falls is a made up of limestone and contains thin fossiliferous beds. It was most likely deposited in shallow water due to the presence of ripple marks.[1]

Stratigraphy

In exposures in the Mohawk Valley this unit is approximately 17' thick. It contains highly fossiliferous beds made of limestone.[2]

The Shoreham member is the upper member of the formation. It contains much more clay and silica, resulting in beds of shale. Name after a quarry in Vermont.

The Larrabee Member is the lower member. It contains some clay in silica but has more carbonate material than the Shoreham. Name after a quarry in Vermont.[3]

Fossils

Trilobite Cryptolithus[4]

Economic Uses

The limestone in the Glens Falls has been used for agricultural lime, used as lime for cement manufacturing, and crushed aggregate for road beds.


References

  1. ↑ "Geolex — GlensFalls publications". ngmdb.usgs.gov. Archived from the original on 2023-09-22. Retrieved 2023-09-15.
  2. ↑ Ruedemann, Rudolf (1912). The Lower Siluric shales of the Mohawk valley, by Rudolf Ruedemann. Albany: University of the State of New York. doi:10.5962/bhl.title.20499.
  3. ↑ David A. MacLean FACIES RELATIONSHIPS WITHIN THE GLENS FALLS LIMESTONE OF VERMONT AND NEW YORK
  4. ↑ Fisher, D.W., 1965a, Mohawk Valley Strata and structure; New York State Geological Association field guide, 37th Annual meeting, Union College