Henry Formation

Lithostratigraphy: Mason Group >>Henry Formation
Chronostratigraphy: Cenozoic Erathem >>Quaternary System >>Pleistocene Series

Primary source

Hansel, Ardith K., and W. Hilton Johnson, 1996, Wedron and Mason Groups: Lithostratigraphic Reclassification of Deposits of the Wisconsin Episode, Lake Michigan Lobe Area: Illinois State Geological Survey Bulletin 104, 116 p.

Contributing author(s)

Ardith K. Hansel and W. Hilton Johnson

Name

Original description

Henry Formation (Willman and Frye 1970).

Derivation

Henry, a village in Marshall County, central Illinois.

History/background

The Henry Formation was defined as glacial outwash composed predominantly of sand and gravel and originally separated from interfingering deposits by vertical boundaries.

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  Figure 9 -- History of the litho-stratigraphic classification of the Mason Group deposits with respect to the Wedron Group deposits: (a) Peoria and Roxana Silts, (b) Henry Formation, and (c) Equality Formation. Vertical lines indicate part of section missing due to erosion.

The formation includes deposits from multiple glacial environments, including outwash plains, valley trains, and ice-contact features.

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  Figure 12 -- Intertongued sorted-sediment units of the Mason Group and diamicton units of the Wedron Group at Wedron Quarry pit 1. Mason Group units are shaded.
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  Figure 19 -- Diamicton (subglacial till) of the Haeger Member of the Lemont Formation overlies the proglacial (ice proximal) sand and gravel of the Beverly Tongue of the Henry Formation at the Beverly Sand and Gravel Pit Section.

Type section

Type location

Gravel pit north of Henry, Illinois.

Reference section

Reference location

Beverly Sand and Gravel Pit and other quarry sections showing relationships with adjacent units.

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  Figure 15 - Lower tongues of the Mason Group Henry and Equality Formation (Ashmore and Peddicord, respectively) beneath the Wedron Group Tiskilwa Formation (Delavan Member) at Charleston Quarry.

Stratigraphic relationships

The Henry Formation consists of stratified sand and gravel above the Sangamon Geosol and interfingers with other formations of the Mason Group and diamicton units of the Wedron Group.

Extent and thickness

The formation is widespread but discontinuous, commonly forming sheetlike, ribbonlike, or moundlike deposits associated with glacial and fluvial systems.

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  Plate 1 -- Quaternary Deposits of Illinois

Lithology

The Henry Formation consists primarily of stratified sand and gravel with local lenses of finer sediment and organic material.

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  Figure 30 -- Stratified and crossbedded proglacial sand and gravel of the Henry Formation.

Contacts

Lower boundary: contact with older units or glacial deposits. Upper boundary: contact with younger sediments or land surface.

Age and correlation

Deposited during the Wisconsin Episode and correlates with similar glacial deposits across the Midwest.

Environments of deposition

Outwash, nearshore lacustrine, and eolian environments associated with glacial and postglacial processes.

Remarks

Redescribed unit.

References

(unchanged)

ISGS Codes

ISGS Code and Symbol

Stratigraphic Code	Geo Unit Designation
0230	Qh