Chamberlain's Brook Formation

Chamberlain's Brook Formation Stratigraphic range: 509–506 Ma (Middle Cambrian) PreЄ Є O S D C P T J K Pg N ↓
Type	Formation
Unit of	Adeyton Group
Sub-units	Fossil Brook Member (and others)
Underlies	Manuels River Formation (unconformably?)
Thickness	up to 14 m
Lithology
Primary	Green, purple and red siliciclastic marine mudstones
Location
Region	Atlantic coast
Country	United States  Canada
Occurrence of the Chamberlain's Brook Formation in southeastern Newfoundland

 United States

The Chamberlain's Brook Formation is a thin but distinctive geologic formation of dark red calcareous mudstones that crops out from Rhode Island to Massachusetts and, Nova Scotia, New Brunswick and Newfoundland. It preserves fossils, including trilobites, dating back to the lower mid-Cambrian period. Its lowermost member is the Braintree Member (lowest Middle Cambrian) and the uppermost member is the Fossil Brook Member.

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