Chickies Formation

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The Cambrian Chickies Formation (Cch) is a mapped bedrock unit in Pennsylvania and Maryland. It is named for Chickies Rock, north of Columbia, Pennsylvania along the Susquehanna River.

1 Description
2 Depositional Age
3 Economic Uses
4 References
5 See also

[edit] Description

The Chickies is described as a light-gray to white, hard, massive quartzite and quartz schist with thin interbedded dark slate at top. Included at the base is the Hellam Conglomerate Member. A rare metamorphic rock that has fossils; Scolithus is found throughout the formation.^[1]

[edit] Depositional Age

Relative age dating places the Chickies in the lower Cambrian period, deposited between 542 mya to 520 mya (±2 my).^[2]

[edit] Economic Uses

The Chickies is quarried as a building stone and for aggregate. The stone used to build the restrooms at Valley Forge National Historical Park is Chickies quartizite. ^[3]

[edit] References

^ Berg, T.M., Edmunds, W.E., Geyer, A.R. and others, compilers, (1980). Geologic Map of Pennsylvania: Pennsylvania Geologic Survey, Map 1, scale 1:250,000.
^ Blackmer, G.C., (2005). Preliminary Bedrock Geologic Map of a Portion of the Wilmington 30- by 60-Minute Quadrangle, Southeastern Pennsylvania. Pennsylvania Geologic Survey, Open-File Report OFBM-05-01.0.
^ http://www.dcnr.state.pa.us/topogeo/ParkGuides/pg08.pdf