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Geologic units in Aroostook county, Maine

Devonian Seboomook Formation (Devonian) at surface, covers 40 % of this area

Devonian Seboomook Formation

Lithology: mudstone; sandstone

Silurian - Ordovician Carys Mills Formation (Silurian - Ordovician) at surface, covers 9 % of this area

Silurian - Ordovician Carys Mills Formation

Devonian - Silurian Madrid Formation (Devonian - Silurian) at surface, covers 6 % of this area

Devonian - Silurian Madrid Formation

Ordovician Winterville Formation (Ordovician) at surface, covers 4 % of this area

Ordovician Winterville Formation

Lithology: basalt

Ordovician - Cambrian Saint Daniel formation (Ordovician - Cambrian) at surface, covers 3 % of this area

Ordovician - Cambrian Saint Daniel formation

Lithology: melange

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

Silurian Smyrna Mills Formation

Ordovician Madawaska Lake Formation (Ordovician) at surface, covers 3 % of this area

Ordovician Madawaska Lake Formation

Lithology: mudstone; sandstone

Silurian undifferentiated pelites and sandstones (Silurian) at surface, covers 3 % of this area

Silurian undifferentiated pelites and sandstones, in part of the Allsbury Formation and in part unnamed

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

Devonian Swanback Formation

Lithology: mudstone

Silurian New Sweden Formation (Silurian) at surface, covers 2 % of this area

Silurian New Sweden Formation

Lithology: mudstone

Devonian Seboomook Formation unnamed pelite (Devonian) at surface, covers 2 % of this area

Devonian Seboomook Formation unnamed pelite

Lithology: mudstone

Ordovician sandstone and pelite of the Depot Mountain sequence (Ordovician) at surface, covers 2 % of this area

Ordovician sandstone and pelite of the Depot Mountain sequence

Devonian - Silurian unnamed sedimentary rocks (Devonian - Silurian) at surface, covers 2 % of this area

Devonian - Silurian unnamed sedimentary rocks

Lithology: mudstone; sandstone

Silurian Frenchville Formation (Silurian) at surface, covers 1 % of this area

Silurian Frenchville Formation

Lithology: sandstone; conglomerate

Silurian Jemtland Formation (Silurian) at surface, covers 1 % of this area

Silurian Jemtland Formation

Lithology: mudstone; sandstone

Silurian Spragueville Formation (Silurian) at surface, covers 1 % of this area

Silurian Spragueville Formation

Cambrian Grand Pitch Formation (Cambrian) at surface, covers 1 % of this area

Cambrian Grand Pitch Formation

Lithology: mudstone; sandstone

Devonian - Silurian Fish River Lake Formation (Devonian - Silurian) at surface, covers 0.9 % of this area

Devonian - Silurian Fish River Lake Formation

Devonian - Silurian Fogelin Hill Formation (Devonian - Silurian) at surface, covers 0.7 % of this area

Devonian - Silurian Fogelin Hill Formation

Lithology: mudstone; sandstone

Devonian - Silurian Bell Brook Formation, pelite member (Devonian - Silurian) at surface, covers 0.7 % of this area

Devonian - Silurian Bell Brook Formation pelite member

Lithology: mudstone

Ordovician unnamed volcanic rocks (Ordovician) at surface, covers 0.7 % of this area

Ordovician unnamed volcanic rocks

Ordovician - Cambrian unnamed sedimentary rocks (Ordovician - Cambrian) at surface, covers 0.6 % of this area

Ordovician - Cambrian unnamed sedimentary rocks

Lithology: mudstone; sandstone

Ordovician Munsungun Lake Formation (Ordovician) at surface, covers 0.6 % of this area

Ordovician Munsungun Lake Formation

Silurian - Ordovician Dunn Brook formation (Silurian - Ordovician) at surface, covers 0.6 % of this area

Silurian - Ordovician Dunn Brook formation

Ordovician - Cambrian Chase Brook Formation (Ordovician - Cambrian) at surface, covers 0.5 % of this area

Ordovician - Cambrian Chase Brook Formation

Lithology: slate; limestone; siltstone

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

Devonian granite

Lithology: granite

Devonian granite (hornblende accessory mineral) (Devonian) at surface, covers 0.5 % of this area

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

Lithology: granite

Devonian unnamed sedimentary rocks (Devonian) at surface, covers 0.5 % of this area

Devonian unnamed sedimentary rocks

Lithology: mudstone; sandstone

Ordovician graywacke of the Depot Mountain sequence (Ordovician) at surface, covers 0.5 % of this area

Ordovician graywacke of the Depot Mountain sequence

Lithology: graywacke

Silurian - Ordovician Mattawamkeag Formation (Silurian - Ordovician) at surface, covers 0.5 % of this area

Silurian - Ordovician Mattawamkeag Formation

Lithology: mudstone; sandstone

Silurian unnamed conglomerate (Silurian) at surface, covers 0.5 % of this area

Silurian unnamed conglomerate

Silurian unnamed limestone (Silurian) at surface, covers 0.4 % of this area

Silurian unnamed limestone

Devonian Chapman Sandstone (Devonian) at surface, covers 0.4 % of this area

Devonian Chapman Sandstone

Lithology: sandstone; shale

Silurian unnamed sandstone (Silurian) at surface, covers 0.4 % of this area

Silurian unnamed sandstone

Lithology: sandstone

Devonian Hedgehog Formation (Devonian) at surface, covers 0.4 % of this area

Devonian Hedgehog Formation

Devonian unnamed pelite (Devonian) at surface, covers 0.4 % of this area

Devonian unnamed pelite

Lithology: mudstone

Silurian rocks of the Fivemile Brook sequence (Silurian) at surface, covers 0.3 % of this area

Silurian rocks of the Fivemile Brook sequence

Lithology: phyllite; limestone; basalt

Silurian - Ordovician Carys Mills Formation lower member (Silurian - Ordovician) at surface, covers 0.3 % of this area

Silurian - Ordovician Carys Mills Formation lower member

Lithology: slate; graywacke

Ordovician Chandler Ridge Formation (Ordovician) at surface, covers 0.2 % of this area

Ordovician Chandler Ridge Formation

Silurian - Ordovician Carys Mills Formation pelite member (Silurian - Ordovician) at surface, covers 0.2 % of this area

Silurian - Ordovician Carys Mills Formation pelite member

Lithology: mudstone

Silurian unnamed sedimentary rocks (Silurian) at surface, covers 0.2 % of this area

Silurian unnamed sedimentary rocks

Undifferentiated volcanic rocks of the Spider Lake and Chandler Pond Formations (Devonian - Silurian) at surface, covers 0.2 % of this area

Undifferentiated volcanic rocks of the Spider Lake and Chandler Pond Formations

Lithology: andesite

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

Silurian Maple Mountain Formation

Lithology: mudstone; sandstone

Ordovician quartz diorite (hornblende accessory mineral) (Ordovician) at surface, covers 0.2 % of this area

Ordovician quartz diorite (hornblende accessory mineral)

Lithology: quartz diorite

Silurian Burnt Brook Formation (Silurian) at surface, covers 0.2 % of this area

Silurian Burnt Brook Formation

Lithology: mudstone

Devonian - Silurian Daggett Ridge Formation (Devonian - Silurian) at surface, covers 0.2 % of this area

Devonian - Silurian Daggett Ridge Formation

Lithology: sandstone; conglomerate

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

Ordovician unnamed pelite

Lithology: mudstone

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

Silurian - Ordovician unnamed pelite

Lithology: mudstone

Ordovician - Cambrian Saint Daniel formation quartzite and red and green shale (Ordovician - Cambrian) at surface, covers 0.1 % of this area

Ordovician - Cambrian Saint Daniel formation quartzite and red and green shale

Lithology: sandstone; shale

Silurian - Ordovician Nine Lake formation (Silurian - Ordovician) at surface, covers 0.1 % of this area

Silurian - Ordovician Nine Lake formation

Lithology: mudstone; sandstone

Devonian Mapleton Formation (Devonian) at surface, covers 0.1 % of this area

Devonian Mapleton Formation

Lithology: sandstone; conglomerate

Devonian - Silurian Bell Brook Formation, conglomerate member (Devonian - Silurian) at surface, covers 0.1 % of this area

Devonian - Silurian Bell Brook Formation, conglomerate member

Lithology: conglomerate

Ordovician tuff of the Depot Mountain sequence (Ordovician) at surface, covers < 0.1 % of this area

Ordovician tuff of the Depot Mountain sequence

Silurian undifferentiated sandstones (Silurian) at surface, covers < 0.1 % of this area

Silurian undifferentiated sandstones, in part of the Allsbury Formation and in part unnamed

Lithology: sandstone

Devonian Edmunds Hill Andesite (Devonian) at surface, covers < 0.1 % of this area

Devonian Edmunds Hill Andesite

Lithology: andesite

Silurian greenstone rocks of the Fivemile Brook sequence (Silurian) at surface, covers < 0.1 % of this area

Silurian greenstone rocks of the Fivemile Brook sequence

Lithology: greenstone

Silurian undifferentiated conglomerates and coarse-grained sandstones (Silurian) at surface, covers < 0.1 % of this area

Silurian undifferentiated conglomerates and coarse-grained sandstones, in part of the Allsbury Formation and in part unnamed

Lithology: conglomerate; sandstone

Silurian Rocky Mountain Quartz Latite (Silurian) at surface, covers < 0.1 % of this area

Silurian Rocky Mountain Quartz Latite

Lithology: quartz latite

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

Silurian unnamed volcanic and sedimentary rocks

Devonian - Ordovician Spruce Top Greenstone (Devonian - Ordovician) at surface, covers < 0.1 % of this area

Devonian - Ordovician Spruce Top Greenstone

Lithology: greenstone

Devonian - Silurian undifferentiated sedimentary rocks of the Spider Lake, Chandler Pond and Third Lake Formations (Devonian - Silurian) at surface, covers < 0.1 % of this area

Devonian - Silurian undifferentiated sedimentary rocks of the Spider Lake, Chandler Pond and Third Lake Formations

Devonian Seboomook Formation unnamed quartzite (Devonian) at surface, covers < 0.1 % of this area

Devonian Seboomook Formation unnamed quartzite

Lithology: quartzite

Devonian granodiorite (hornblende accessory mineral) (Devonian) at surface, covers < 0.1 % of this area

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

Lithology: granodiorite

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

Devonian Hartin Formation

Lithology: sandstone

Silurian - Ordovician Aroostook River Formation (Silurian - Ordovician) at surface, covers < 0.1 % of this area

Silurian - Ordovician Aroostook River Formation

Lithology: slate; graywacke; siltstone

Silurian - Ordovician Mars Hill Conglomerate (Silurian - Ordovician) at surface, covers < 0.1 % of this area

Silurian - Ordovician Mars Hill Conglomerate

Lithology: conglomerate

Devonian granodiorite (hornblende accessory mineral, porphyritic texture) (Devonian) at surface, covers < 0.1 % of this area

Devonian granodiorite (hornblende accessory mineral, porphyritic texture) - porphyritic hornblende-biotite granodiorite

Lithology: granodiorite

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

Ordovician granodiorite - Ordovician biotite granodiorite

Lithology: granodiorite

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

Devonian syenite, monzodiorite (porphyritic texture) - Devonian pyroxene-hornblende-biotite syenite and monzodiorite

Lithology: syenite; monzodiorite

Ordovician Pile Mountain Argillite (Ordovician) at surface, covers < 0.1 % of this area

Ordovician Pile Mountain Argillite

Lithology: argillite

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

Ordovician gabbro/diorite/ultramafic rocks

Ordovician Shin Brook Formation (Ordovician) at surface, covers < 0.1 % of this area

Ordovician Shin Brook Formation

Ordovician Chase lake formation (Ordovician) at surface, covers < 0.1 % of this area

Ordovician Chase lake formation

Ordovician unnamed felsic volcanic rocks (Ordovician) at surface, covers < 0.1 % of this area

Ordovician unnamed felsic volcanic rocks

Ordovician Belle Lake Slate (Ordovician) at surface, covers < 0.1 % of this area

Ordovician Belle Lake Slate

Lithology: slate

Ordovician unnamed mafic volcanic rocks (Ordovician) at surface, covers < 0.1 % of this area

Ordovician unnamed mafic volcanic rocks

Ordovician unnamed sandstone and pelite (Ordovician) at surface, covers < 0.1 % of this area

Ordovician unnamed sandstone and pelite

Lithology: mudstone; sandstone

Devonian unnamed limestone conglomerate (Devonian) at surface, covers < 0.1 % of this area

Devonian unnamed limestone conglomerate

Lithology: conglomerate

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

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

Lithology: granite

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

Ordovician unnamed sulfidic pelite

Lithology: mudstone

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

Ordovician unnamed volcanic and sedimentary rocks

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

Devonian granite (granophyric texture)

Lithology: granite

Devonian syenite (pyroxene plus hornblende accessory mineral) (Devonian) at surface, covers < 0.1 % of this area

Devonian syenite (pyroxene plus hornblende accessory mineral) - Devonian pyroxene-hornblende-biotite syenite undivided

Lithology: syenite

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

Devonian unnamed conglomerate

Lithology: conglomerate

Silurian - Precambrian Z ultramafic rocks (Silurian - Precambrian Z) at surface, covers < 0.1 % of this area

Silurian - Precambrian Z ultramafic rocks