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Mineral Resources > Online Spatial Data > Geology > by state > Maine Geology

Geologic units in York county, Maine

[Additional scientific data in this geographic area]

Perry Mountain Formation, undivided (Lower? - Middle? Silurian) at surface, covers < 0.1 % of this area

Perry Mountain Formation, undivided - Sharply interbedded quartzites, light-gray nongraphitic metapelite, and "fast-graded" meta-turbidites. Coticule layers common.

Lithology: quartzite; meta-argillite; metasedimentary rock

Devonian - Silurian Towow Formation conglomerate (Devonian - Silurian) at surface, covers 0.3 % of this area

Devonian - Silurian Towow Formation conglomerate

Lithology: conglomerate

Devonian granite (Devonian) at surface, covers 7 % of this area

Devonian granite

Lithology: granite

Cretaceous gabbro/diorite/ultramafic rocks (Cretaceous) at surface, covers 0.4 % of this area

Cretaceous gabbro/diorite/ultramafic rocks

Lithology: gabbro; diorite; ultramafic intrusive rock

Merrimack Group, Kittery Formation (Ordovician? - Silurian?) at surface, covers < 0.1 % of this area

Merrimack Group, Kittery Formation - Tan, graded-bedded, calcareous metasandstone and purple and green phyllite. Grades into the Eliot formation but facing direction is uncertain.

Lithology: metasedimentary rock; phyllite

Devonian - Precambrian Z Gonic Formation (Devonian - Precambrian Z) at surface, covers 0.9 % of this area

Devonian - Precambrian Z Gonic Formation

Lithology: schist; phyllite

Merrimack Group, Berwick Formation (Ordovician? - Silurian?) at surface, covers < 0.1 % of this area

Merrimack Group, Berwick Formation - Purple biotite-quartz-feldspar granofels or schist and interbeds of calc-silicate granofels and minor metapelites. Stratigraphic sequence with respect to Eliot Formation uncertain

Lithology: granofels; quartz-feldspar schist; meta-argillite

Ordovician - Precambrian Z Cape Elizabeth Formation (Ordovician - Precambrian Z) at surface, covers 2 % of this area

Ordovician - Precambrian Z Cape Elizabeth Formation

Lithology: slate; schist; quartzite; phyllite

Precambrian Z Rye Formation (Precambrian) at surface, covers 0.1 % of this area

Precambrian Z Rye Formation

Lithology: metasedimentary rock; metavolcanic rock; phyllite; marble; amphibolite

Lower part of Rangeley Formation (Lower Silurian (Llandoverian)) at surface, covers < 0.1 % of this area

Lower part of Rangeley Formation - Gray, thinly laminated (5-25 mm) metapelite with local lentils of turbidites and thin quartz conglomerates in western New Hampshire. Sparse calc-silicate pods and coticule. Probably equivalent to member B of Rangeley Formation of Maine.

Lithology: meta-argillite; meta-conglomerate; calc-silicate rock

Devonian gabbro/diorite/ultramafic rocks (Devonian) at surface, covers < 0.1 % of this area

Devonian gabbro/diorite/ultramafic rocks

Lithology: gabbro; diorite; ultramafic intrusive rock

Smalls Falls Formation, undivided (Upper to Middle Silurian (Ludlovian and Wenlockian)) at surface, covers < 0.1 % of this area

Smalls Falls Formation, undivided -Very rusty weathering, thinly bedded sulfidic-graphitic schist and pyrrhotitic calc-silicate granofels. Eastern facies equivalent to lower part of the Fitch Formation. Locally mapped as Francestown Formation of Nielson (1981) in southern New Hampshire.

Lithology: schist; granofels

Devonian - Silurian Rindgemere Formation lower member sulfidic pelite (Devonian - Silurian) at surface, covers 1 % of this area

Devonian - Silurian Rindgemere Formation lower member sulfidic pelite

Lithology: mudstone

Silurian Waterville Formation limestone member (Silurian) at surface, covers 0.1 % of this area

Silurian Waterville Formation limestone member

Lithology: calc-silicate rock; metasedimentary rock; marble; slate; schist; black shale

Cretaceous intrusive breccia (Cretaceous ) at surface, covers < 0.1 % of this area

Cretaceous intrusive breccia

Lithology: breccia

Mesozoic alkali feldspar syenite (Mesozoic) at surface, covers < 0.1 % of this area

Mesozoic alkali feldspar syenite - Mesozoic alkali feldspar-biotite syenite

Lithology: alkali syenite

Littleton Formation, undivided (Lower Devonian; Siegenian) at surface, covers < 0.1 % of this area

Littleton Formation undivided - Gray metapelite and metawacke and subordinate metavolcanic rocks; generally, but not everywhere, conformable with underlying Fitch or Madrid Formations. Fossiliferous in western New Hampshire.

Lithology: metasedimentary rock; metavolcanic rock

Merrimack Group, Eliot Formation (Ordovician? - Silurian?) at surface, covers < 0.1 % of this area

Merrimack Group, Eliot Formation - Gray to green phyllite, calcareous quartzite, quartz-mica schist, and well-bedded calc-silicate.

Lithology: phyllite; quartzite; mica schist; calc-silicate rock

Carboniferous alkali feldspar granite (muscovite accessory mineral) (Carboniferous) at surface, covers < 0.1 % of this area

Carboniferous alkali feldspar granite (muscovite accessory mineral) - muscovite-biotite granite

Lithology: granite

Carboniferous granite (muscovite accessory mineral) (Carboniferous) at surface, covers 8 % of this area

Carboniferous granite (muscovite accessory mineral) - muscovite-biotite granite undivided

Lithology: granite

Silurian - Ordovician Vassalboro formation (Silurian - Ordovician) at surface, covers 8 % of this area

Silurian - Ordovician Vassalboro formation

Lithology: sandstone; quartzite; schist; limestone

Mesozoic gabbro/diorite/ultramafic rocks (Mesozoic) at surface, covers < 0.1 % of this area

Mesozoic gabbro/diorite/ultramafic rocks

Lithology: gabbro; diorite; ultramafic intrusive rock

Devonian granodiorite (Devonian) at surface, covers 2 % of this area

Devonian granodiorite - biotite granodiorite

Lithology: granodiorite

Two-mica granite of northern and southeastern New Hampshire (Early - Late Devonian) at surface, covers < 0.1 % of this area

Two-mica granite of northern and southeastern New Hampshire - Similar to Concord Granite.

Lithology: granite

Cretaceous quartz monzodiorite (Cretaceous) at surface, covers < 0.1 % of this area

Cretaceous quartz monzodiorite - Cretaceous biotite quartz monzodiorite

Lithology: quartz monzodiorite

Silurian - Precambrian Z Eliot Formation (Silurian - Precambrian Z) at surface, covers 2 % of this area

Silurian - Precambrian Z Eliot Formation

Lithology: phyllite; quartzite; schist; calc-silicate rock

Ordovician - Precambrian Z Scarboro and Diamond Island formations (Ordovician - Precambrian Z) at surface, covers 0.6 % of this area

Ordovician - Precambrian Z Scarboro and Diamond Island formations

Lithology: metasedimentary rock

Cretaceous alkali feldspar granite (Cretaceous) at surface, covers 1 % of this area

Cretaceous alkali feldspar granite - Cretaceous alkali feldspar-biotite granite

Lithology: alkali-granite (alaskite)

Devonian - Silurian Rindgemere Formation lower member limestone (Devonian - Silurian) at surface, covers 2 % of this area

Devonian - Silurian Rindgemere Formation lower member limestone

Lithology: limestone

Two-mica granite of the Sebago batholith and Effingham pluton of eastern New Hampshire (Mississippian - Pennsylvanian) at surface, covers < 0.1 % of this area

Two-mica granite of the Sebago batholith and Effingham pluton of eastern New Hampshire.

Lithology: granite

Silurian - Precambrian Z Berwick Formation (Silurian - Precambrian Z) at surface, covers 9 % of this area

Silurian - Precambrian Z Berwick Formation

Lithology: gneiss; quartzite; schist; slate

Concord Granite (Late Devonian ) at surface, covers < 0.1 % of this area

Concord Granite - Gray two-mica granite, locally grading to tonalite.

Lithology: granite; tonalite

Devonian granite (muscovite accessory mineral) (Devonian) at surface, covers 1 % of this area

Devonian granite (muscovite accessory mineral) - muscovite-biotite granite undivided

Lithology: granite

Silurian Waterville Formation (Silurian) at surface, covers 0.5 % of this area

Silurian Waterville Formation

Lithology: slate; schist; graywacke; calc-silicate rock; black shale

Cretaceous alkali feldspar syenite (Cretaceous) at surface, covers 0.7 % of this area

Cretaceous alkali feldspar syenite - Cretaceous alkali feldspar-biotite syenite

Lithology: alkali syenite

Cretaceous monzodiorite (Cretaceous) at surface, covers 0.2 % of this area

Cretaceous monzodiorite - Cretaceous biotite monzodiorite

Lithology: monzodiorite

Carboniferous gabbro/diorite/ultramafic rocks (Carboniferous) at surface, covers 1 % of this area

Carboniferous gabbro/diorite/ultramafic rocks undivided

Lithology: gabbro; diorite; ultramafic intrusive rock

Carboniferous granite undivided (Carboniferous) at surface, covers 4 % of this area

Carboniferous granite undivided - biotite granite

Lithology: granite

Silurian - Precambrian Z Kittery Formation (Silurian - Precambrian Z) at surface, covers 10 % of this area

Silurian - Precambrian Z Kittery Formation

Lithology: metasedimentary rock; phyllite

Madrid Formation (Upper Silurian? ) at surface, covers < 0.1 % of this area

Madrid Formation - Massive to weakly foliated, purple biotite-feldspar granofels, layered calc-silicate, and dark pelitic-sulfidic schist containing calc-silicate pods in upper member; an eastern facies equivalent to the upper part of the Fitch Formation. Locally mapped as the Warner Formation of Nielson (1981) in southern New Hampshire.

Lithology: granofels; calc-silicate schist; pelitic schist

Cretaceous granite (Cretaceous) at surface, covers 0.5 % of this area

Cretaceous granite - Cretaceous biotite granite

Lithology: granite

Devonian - Silurian Rindgemere Formation upper member (Devonian - Silurian) at surface, covers 33 % of this area

Devonian - Silurian Rindgemere Formation upper member

Lithology: mudstone; sandstone

Silurian - Ordovician Vassalboro Formation volcanic rocks (Silurian - Ordovician) at surface, covers < 0.1 % of this area

Silurian - Ordovician Vassalboro Formation volcanic rocks

Lithology: felsic volcanic rock

Devonian - Silurian Rindgemere Formation lower member (Devonian - Silurian) at surface, covers < 0.1 % of this area

Devonian - Silurian Rindgemere Formation lower member

Lithology: mudstone; limestone; dolostone (dolomite)

Devonian - Silurian Towow Formation (Devonian - Silurian) at surface, covers 1 % of this area

Devonian - Silurian Towow Formation

Lithology: mudstone

Upper part of Rangeley Formation (Lower Silurian (Llandoverian)) at surface, covers < 0.1 % of this area

Upper part of Rangeley Formation - Rusty-weathering, pelitic schist, metasandstone, and local coarse-grained metasandstone lentils; calc-silicate pods common; minor coticule. Probably equivalent to member C of Rangeley Formation of Maine.

Lithology: pelitic schist; metasedimentary rock; calc-silicate rock

Cretaceous alkali feldspar quartz syenite (Cretaceous) at surface, covers 1 % of this area

Cretaceous alkali feldspar quartz syenite - Cretaceous alkali feldspar-biotite quartz syenite

Lithology: quartz syenite

Mesozoic granite (hornblende accessory mineral) (Mesozoic) at surface, covers 0.3 % of this area

Mesozoic granite (hornblende accessory mineral) - Mesozoic hornblende-biotite granite undivided

Lithology: granite

Mesozoic mafic to felsic volcanic rocks (Mesozoic) at surface, covers < 0.1 % of this area

Mesozoic mafic to felsic volcanic rocks

Lithology: mafic volcanic rock; felsic volcanic rock

Cretaceous quartz diorite - gabbro/diorite/ultramafic rocks (Cretaceous) at surface, covers 0.1 % of this area

Cretaceous quartz diorite - gabbro/diorite/ultramafic rocks - Cretaceous biotite quartz diorite and gabbro/diorite/ultramafic rocks

Lithology: quartz diorite; gabbro; diorite; ultramafic intrusive rock