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Geologic units in Rappahannock county, Virginia

Additional scientific data in this geographic area

Porphyoblastic Biotite-Plagioclase Augen Gneiss (Proterozoic Y) at surface, covers 29 % of this area

Porphyoblastic biotite-plagioclase augen gneiss

Lithology: augen gneiss

Layered Pyroxene Granulite (Proterozoic Y) at surface, covers 15 % of this area

Layered pyroxene granulite

Lithology: granulite

Flint Hill Gneiss (Proterozoic Y) at surface, covers 15 % of this area

Flint Hill Gneiss - Gneiss.

Lithology: gneiss

Charnockite Gneiss (Proterozoic Y) at surface, covers 11 % of this area

Charnockite gneiss

Lithology: gneiss

Catoctin Formation - Metabasalt (Proterozoic Z-Cambrian) at surface, covers 10 % of this area

Catoctin Formation - Metabasalt.

Lithology: meta-basalt

Robertson River Igneous Suite - Battle Mountain granite (Proterozoic Z) at surface, covers 4 % of this area

Robertson River Igneous Suite - Battle Mountain granite

Lithology: granite

Mylonite, Mylonite Gneiss, and Cataclastic Rocks (Proterozoic - Paleozoic ?) at surface, covers 3 % of this area

Mylonite, mylonite gneiss, and cataclastic rocks.

Lynchburg Group; Metagraywacke (Proterozoic Z) at surface, covers 2 % of this area

Lynchburg Group - Metagraywacke

Fauquier Formation - Arkosic metasandstone (Proterozoic Z) at surface, covers 2 % of this area

Fauquier Formation - Arkosic metasandstone

Fauquier Formation -Meta-arkose and metasiltstone (Proterozoic Z) at surface, covers 1 % of this area

Fauquier Formation - Crossbedded metasandstone

Two-Mica Granite (Proterozoic Y) at surface, covers 1 % of this area

Two-mica granite.

Lithology: orthogneiss

Robertson River Igneous Suite - Amissville alkali feldspar granite (Proterozoic Z) at surface, covers 1 % of this area

Robertson River Igneous Suite - Amissville alkali feldspar granite

Lithology: granite

Alkali Feldspar Leucogranite (Proterozoic Y) at surface, covers 1.0 % of this area

Alkali feldspar leucogranite

Lithology: granite

Robertson River Igneous Suite; Battle Mountain Alkali Feldspar Granite - felsite (Proterozoic Z) at surface, covers 0.9 % of this area

Robertson River Igneous Suite - Battle Mountain Alkali Feldspar Granite - felsite

Robertson River Igneous Suite - Arrington Mountain alkali feldspar granite (Proterozoic Z) at surface, covers 0.6 % of this area

Robertson River Igneous Suite - Arrington Mountain alkali feldspar granite

Lithology: granite

Robertson River Igneous Suite - Hitt Mountain alkali feldspar syenite (Proterozoic Z) at surface, covers 0.5 % of this area

Robertson River Igneous Suite - Hitt Mountain alkali feldspar syenite

Lithology: alkali syenite

Marshall Metagranite (Proterozoic Y) at surface, covers 0.4 % of this area

Marshall Metagranite - Medium-granied biotite metagranite

Lithology: granite

Swift Run Formation (Proterozoic Z) at surface, covers 0.4 % of this area

Swift Run Formation - Phyllite, metasandstone, and metaconglomerate.

Fauquier Formation - Metasiltstone and phyllite (Proterozoic Z) at surface, covers < 0.1 % of this area

Fauquier Formation - Meta-argillite is laminated metasiltstone; and phyllite.

Charnockite (Proterozoic Y) at surface, covers < 0.1 % of this area

Charnockite.

Lithology: granitic gneiss