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

Geologic units in Franklin county, Maine

[Additional scientific data in this geographic area]

Devonian granite (Devonian) at surface, covers 3 % of this area

Devonian granite

Lithology: granite

Cambrian ultramafic rocks (Cambrian) at surface, covers 0.2 % of this area

Cambrian ultramafic rocks

Lithology: ultramafic intrusive rock

Silurian Hardwood Mountain Formation (Silurian) at surface, covers 0.2 % of this area

Silurian Hardwood Mountain Formation

Lithology: mudstone; siltstone; slate, conglomerate, limestone, sandstone

Silurian Perry Mountain formation (Silurian) at surface, covers 3 % of this area

Silurian Perry Mountain formation

Lithology: sandstone; shale; quartzite

Silurian Greenvale Cove Formation (Silurian) at surface, covers 0.9 % of this area

Silurian Greenvale Cove Formation

Lithology: metasedimentary rock; calc-silicate rock

Devonian gabbro/diorite/ultramafic rocks (Devonian) at surface, covers 5 % of this area

Devonian gabbro/diorite/ultramafic rocks

Lithology: gabbro; diorite; ultramafic intrusive rock

Silurian Sangerville Formation Anasagunticook member (Silurian) at surface, covers 2 % of this area

Silurian Sangerville Formation Anasagunticook member

Lithology: metasedimentary rock; marble

Devonian - Ordovician unnamed pelite (Devonian - Ordovician) at surface, covers < 0.1 % of this area

Devonian - Ordovician unnamed pelite

Lithology: mudstone

Silurian Sangerville Formation (Silurian) at surface, covers 3 % of this area

Silurian Sangerville Formation

Lithology: sandstone; shale; limestone; calc-silicate rock; granofels; schist; metasedimentary rock; conglomerate

Silurian Sangerville Formation Anasagunticook member limestone (Silurian) at surface, covers 0.2 % of this area

Silurian Sangerville Formation Anasagunticook member limestone

Lithology: marble

Cambrian Jim Pond Formation, quartzwacke and pelite (Cambrian) at surface, covers 0.7 % of this area

Cambrian Jim Pond Formation, quartzwacke and pelite

Lithology: sandstone; mudstone

Silurian Rangeley formation (Silurian) at surface, covers 3 % of this area

Silurian Rangeley formation

Lithology: mudstone; sandstone

Ordovician Quimby formation pelite member (Ordovician) at surface, covers 0.2 % of this area

Ordovician Quimby formation pelite member

Lithology: mudstone

Devonian Seboomook Formation Day Mountain member (Devonian) at surface, covers 5 % of this area

Devonian Seboomook Formation Day Mountain member

Lithology: metasedimentary rock; schist

Cambrian gabbro/diorite/ultramafic rocks (Cambrian) at surface, covers 0.5 % of this area

Cambrian gabbro/diorite/ultramafic rocks

Lithology: gabbro; diorite; ultramafic intrusive rock

Silurian Smalls Falls Formation (Silurian) at surface, covers 2 % of this area

Silurian Smalls Falls Formation

Lithology: shale; sandstone; calc-silicate rock

Ordovician Quimby formation rhyolitic volcanic member (Ordovician) at surface, covers < 0.1 % of this area

Ordovician Quimby formation rhyolitic volcanic member

Lithology: rhyolite

Silurian Rangeley Formation "B" member (Silurian) at surface, covers 2 % of this area

Silurian Rangeley Formation "B" member"

Lithology: conglomerate; sandstone; shale

Silurian - Ordovician unnamed sedimentary rocks (Silurian - Ordovician) at surface, covers < 0.1 % of this area

Silurian - Ordovician unnamed sedimentary rocks

Lithology: mudstone; sandstone

Silurian Sangerville Formation limestone member (Silurian) at surface, covers 0.2 % of this area

Silurian Sangerville Formation limestone member

Lithology: marble; calc-silicate rock; granofels; schist

Silurian Rangeley Formation "A" member lithic sandstone" (Silurian) at surface, covers 1 % of this area

Silurian Rangeley Formation "A" member lithic sandstone

Lithology: sandstone; conglomerate

Ordovician Kamankeag Formation basalt and graywacke member (Ordovician) at surface, covers 0.5 % of this area

Ordovician Kamankeag Formation basalt and graywacke member

Lithology: graywacke; basalt

Devonian granodiorite (hornblende accessory mineral) (Devonian) at surface, covers 0.9 % of this area

Devonian granodiorite (hornblende accessory mineral) - hornblende-biotite granodiorite

Lithology: granodiorite

Devonian gabbro - ultramafic rocks (Devonian) at surface, covers 3 % of this area

Devonian gabbro - ultramafic rocks

Lithology: gabbro; ultramafic intrusive rock

Cambrian Jim Pond Formation, felsic volcanic rocks (Cambrian) at surface, covers 0.2 % of this area

Cambrian Jim Pond Formation, felsic volcanic rocks Volcanic and metasedimentary rocks of the ophiolite sequence in central-western Maine are here named the Jim Pond Formation. It consists of a basal chlorite-albite-epidote-actinolite greenstone member with minor metagraywacke, 150 to 500 m thick. Northwest of the Squirtgun fault it is divided into lower and upper units by a metadacite member in the east, 0 to >500 m thick, and a metagraywacke member in the west. The metadacite member is closely associated with hematitic chert iron-formation members. Greenstone is thickly layered with pillowed and massive flows. Patches of altered amphibolite are in contact with the southeastern belt of tonalite of the Boil Mountain Complex. (ME075) Unit description from USGS GEOLEX website (ME078).

Lithology: felsic volcanic rock

Devonian granite (porphyritic texture) (Devonian) at surface, covers < 0.1 % of this area

Devonian granite (porphyritic texture) - biotite granite undivided

Lithology: granite

Devonian granite (muscovite accessory mineral) (Devonian) at surface, covers 2 % of this area

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

Lithology: granite

Cambrian Jim Pond Formation siltstone, mudstone, and pelite (Cambrian) at surface, covers < 0.1 % of this area

Cambrian Jim Pond Formation siltstone, mudstone, and pelite

Lithology: mudstone; siltstone

Ordovician - Cambrian Dead River formation (Ordovician - Cambrian) at surface, covers < 0.1 % of this area

Ordovician - Cambrian Dead River formation

Lithology: slate; quartzite; phyllite

Silurian Rangeley Formation "C" member (Silurian) at surface, covers 0.8 % of this area

Silurian Rangeley Formation "C" member

Lithology: sandstone; conglomerate; shale; limestone

Devonian granite (Devonian) at surface, covers < 0.1 % of this area

Devonian granite - biotite granite

Lithology: granite

Devonian Carrabassett Formation quartzite member (Devonian) at surface, covers 0.1 % of this area

Devonian Carrabassett Formation quartzite member

Lithology: quartzite

Devonian granodiorite - quartz syenite (porphyritic texture) (Devonian) at surface, covers 0.4 % of this area

Devonian granodiorite - quartz syenite (porphyritic texture) - Devonian porphyritic biotite granodiorite to quartz syenite - porphyritic biotite granodiorite, porphyritic biotite tonalite, porphyritic alkali feldspar-biotite quartz syenite, and porphyritic biotite quartz syenite.

Lithology: granodiorite; tonalite; quartz syenite

Silurian Sangerville Formation Patch Mountain member (Silurian) at surface, covers 0.5 % of this area

Silurian Sangerville Formation Patch Mountain member

Lithology: marble; calc-silicate rock; granofels; schist

Devonian Seboomook Formation (Devonian) at surface, covers 0.9 % of this area

Devonian Seboomook Formation

Lithology: mudstone; sandstone

Devonian granite (muscovite accessory mineral) (Devonian) at surface, covers 3 % of this area

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

Lithology: granite

Silurian - Ordovician unnamed pelite (Silurian - Ordovician) at surface, covers 0.3 % of this area

Silurian - Ordovician unnamed pelite

Lithology: mudstone

Ordovician Quimby formation graywacke member (Ordovician) at surface, covers < 0.1 % of this area

Ordovician Quimby formation graywacke member

Lithology: graywacke

Ordovician - Cambrian Dead River formation upper member (Ordovician - Cambrian) at surface, covers 0.9 % of this area

Ordovician - Cambrian Dead River formation upper member

Lithology: phyllite; quartzite

Ordovician Quimby formation (Ordovician) at surface, covers 4 % of this area

Ordovician Quimby formation

Lithology: shale; graywacke; felsic volcanic rock

Cambrian Jim Pond Formation graywacke (Cambrian) at surface, covers 2 % of this area

Cambrian Jim Pond Formation graywacke

Lithology: graywacke

Ordovician granite (Ordovician) at surface, covers < 0.1 % of this area

Ordovician granite - Ordovician biotite granite

Lithology: granite

Devonian Carrabassett Formation thinly layered member (Devonian) at surface, covers 1 % of this area

Devonian Carrabassett Formation thinly layered member

Lithology: mudstone; sandstone

Cambrian quartz diorite (Cambrian) at surface, covers 0.4 % of this area

Cambrian biotite quartz diorite

Lithology: quartz diorite

Devonian Seboomook Formation Mount Blue member (Devonian) at surface, covers 2 % of this area

Devonian Seboomook Formation Mount Blue member

Lithology: schist; metasedimentary rock

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

Devonian Hildreths Formation

Lithology: calc-silicate rock; marble; graywacke; schist

Ordovician - Cambrian Dead River formation lower member (Ordovician - Cambrian) at surface, covers 2 % of this area

Ordovician - Cambrian Dead River formation lower member

Lithology: quartzite; phyllite

Devonian Seboomook Formation Temple Stream member (Silurian-Devonian) at surface, covers 4 % of this area

Devonian Seboomook Formation Temple Stream member

Lithology: schist; metasedimentary rock; conglomerate

Silurian Rangeley Formation "A""member (Silurian) at surface, covers 0.2 % of this area

Silurian Rangeley Formation "A" member

Lithology: shale; sandstone; conglomerate

Cambrian Hurricane Mountain Formation (Cambrian) at surface, covers 2 % of this area

Cambrian Hurricane Mountain Formation

Lithology: melange

Devonian Seboomook Formation Day Mountain member limestone (Devonian) at surface, covers 0.2 % of this area

Devonian Seboomook Formation Day Mountain member limestone

Lithology: limestone; dolostone (dolomite)

Devonian Carrabassett Formation (Devonian) at surface, covers 3 % of this area

Devonian Carrabassett Formation

Lithology: schist; metasedimentary rock; gneiss

Devonian granodiorite (muscovite accessory mineral) (Devonian) at surface, covers 8 % of this area

Devonian granodiorite (muscovite accessory mineral) - muscovite-biotite granodiorite

Lithology: granodiorite

Ordovician granodiorite (Ordovician) at surface, covers 0.6 % of this area

Ordovician granodiorite - Ordovician biotite granodiorite

Lithology: granodiorite

Ordovician Kamankeag Formation pelite member (Ordovician) at surface, covers 0.5 % of this area

Ordovician Kamankeag Formation pelite member

Lithology: mudstone

Precambrian gneisses of the Chain Lakes Massif (Precambrian) at surface, covers 11 % of this area

Precambrian gneisses of the Chain Lakes Massif

Lithology: felsic gneiss

Cambrian Jim Pond Formation (Cambrian) at surface, covers 0.5 % of this area

Cambrian Jim Pond Formation

Lithology: greenstone; felsic metavolcanic rock; metasedimentary rock, amphibolite, iron formation

Cambrian Jim Pond Formation mafic volcanic rocks (Cambrian) at surface, covers 0.3 % of this area

Cambrian Jim Pond Formation mafic volcanic rocks

Lithology: greenstone

Devonian - Silurian Madrid Formation (Devonian - Silurian) at surface, covers 5 % of this area

Devonian - Silurian Madrid Formation

Lithology: quartzite; calc-silicate rock

Devonian Seboomook Formation Day Mountain member conglomerate (Devonian) at surface, covers 0.1 % of this area

Devonian Seboomook Formation Day Mountain member conglomerate

Lithology: conglomerate

Devonian Carrabassett Formation massive pelite member (Devonian) at surface, covers 3 % of this area

Devonian Carrabassett Formation massive pelite member

Lithology: mudstone

Devonian granite-quartz diorite (Devonian) at surface, covers < 0.1 % of this area

Devonian granite-quartz diorite: biotite granite, biotite granodiorite, biotite tonalite, biotite quartz syenite, biotite quartz monzodiorite, and biotite quartz diorite.

Lithology: granite; granodiorite; tonalite; quartz syenite; quartz monzodiorite; quartz diorite

Devonian Ironbound Mountain Formation (Devonian) at surface, covers 0.7 % of this area

Devonian Ironbound Mountain Formation

Lithology: slate