Sharon Syenite appears to have been produced by interaction between Dedham Granite and older gabbro and diorite. Thus, age changed from Devonian or older to Proterozoic Z.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Used as Sharon Syenite of Proterozoic Z age.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Proterozoic Z Sharon Syenite forms long narrow mass along southeast side of Norfolk basin. Consists of gray to dark-gray syenite and minor ferrogabbro. Both rock types are intruded by Proterozoic Z Dedham Granite, but relationship to other Proterozoic Z gabbros is unknown. Near Sharon, unit is intruded by unnamed Proterozoic Z diorite. Report includes geologic maps. [Papers presented as chapters in U.S. Geological Survey Professional Paper 1366 are intended as explanations and (or) revisions to MA State bedrock geologic map of Zen and others (1983) at scale of 1:250,000.]
Source: GNU records (USGS DDS-6; Reston GNULEX).
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