Named for Chase Brook, Piscataquis Co., north-central ME. Consists of gray, black, and green-gray slate with interbedded limestone and siltstone. Thickness is 760 m. Unconformably underlies Chase Lake Formation. Age is Cambrian(?).
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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