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Mineral Resources On-Line Spatial Data
Mineral Resources On-Line Spatial Data
| State | Maine |
|---|---|
| Name | Ordovician - Cambrian Chase Brook Formation |
| Geologic age | Ordovician - Cambrian |
| Comments | 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(?). (ME017) Unit description from USGS GEOLEX website (ME078). W - Weakly metamorphosed; contains local occurrences of prehnite and pumpellyite Protolith Z - Melange |
| Primary rock type | slate |
| Secondary rock type | limestone |
| Other rock types | siltstone |
| Lithologic constituents |
Major
Metamorphic > Metasedimentary > Metaclastic > SlateW - Weakly metamorphosed; contains local occurrences of prehnite and pumpellyite Protolith Z - Melange
Minor
Sedimentary > Carbonate > LimestoneW - Weakly metamorphosed; contains local occurrences of prehnite and pumpellyite Protolith Z - Melange
Sedimentary > Clastic > SiltstoneW - Weakly metamorphosed; contains local occurrences of prehnite and pumpellyite Protolith Z - Melange
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| Map references |
Digital bedrock data downloaded from Maine Office of GIS in September 2005 from http://apollo.ogis.state.me.us/catalog/catalog.asp?state=2&extent=cover#bedrock Bedrock units table (publication date 11/15/2002) downloaded from same site. Permission to redistribute these data granted by Dr. Robert Marvinney, State Geologist of Maine, in September 2006.
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| Unit references |
Osberg, P. H., Hussey, A.M., and Boone, G. M., 1985, Bedrock geologic map of Maine: Maine Geological Survey, Dept. of Conserv., scale 1:500,000.
Hall, B.A., 1970, Stratigraphy of the southern end of the Munsungun anticlinorium, Maine: Maine Geol. Surv., Bull. 22, 63 p.
USGS Geologic Names Lexicon (GEOLEX)
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| Counties | Aroostook - Piscataquis |