State | Rhode Island |
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Name | minette |
Geologic age | Cambro-Ordovician? to Carboniferous? |
Lithologic constituents | Major
Igneous > Hypabyssal > Lamprophyre (Dike or sill)minette - Olive-gray to pale-gray, 1- to 4-m-wide dikes, mostly massive and porphyritic, but locally schistose, composed of biotite phenocrysts in a fine-grained groundmass of microcline, plagioclase, and quartz. Contains accessory apatite and pyrite, and secondary chlorite, sericite, calcite, and opaque minerals.
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Comments | Part of Esmond-Dedham Subterrane (East Bay Area). Printed map unit symbol is OCm, digital is OCmn. |
References | Hermes, O.D. (comp.), Gromet, L.P. (comp.), Murray, D.P. (comp.), Hamidzada, N.A., Skehan, J.W., and Mosher, S., 1994, Bedrock geologic map of Rhode Island: Rhode Island Map Series No. 1, Kingston, Rhode Island, scale 1:100,000. |
NGMDB product | |
Counties | Newport |