| State | Maine |
|---|---|
| Name | Silurian Maple Mountain Formation |
| Geologic age | Silurian |
| Lithologic constituents | Major
Sedimentary > Clastic > Mudstone (Bed)W - Weakly metamorphosed; contains local occurrences of prehnite and pumpellyite; Protolith Q - Interbedded pelite and sandstone
Sedimentary > Clastic > Sandstone (Bed)W - Weakly metamorphosed; contains local occurrences of prehnite and pumpellyite; Protolith Q - Interbedded pelite and sandstone
|
| Comments | Secondary unit description from USGS Geologic Names lexicon (ref. ME078): Named the Hersey red shale member of the Pembroke formation for exposures on Hersey Neck, Washington Co., ME. Consists of purplish red fossiliferous shale; includes some gray shale like that of Leighton member. Thickness is 2700 feet. The Hersey is the top member of the Pembroke formation and is separated from the older Leighton gray shale member by rhyolite tuff. Unit is of Late Silurian age. GS - Greenschist facies; Protolith Q - Interbedded pelite and sandstone |
| Stratigraphic units | Hovey Group |
| 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.Pavlides, L., 1964, The Hovey Group of northeastern Maine: U.S. Geol. Surv., Bull. 1194-B, 6 p. |
| NGMDB product | |
| Counties | Aroostook |