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Mineral Resources > Online Spatial Data > Geology > by state > New York Geology

Geologic units in Putnam county, New York

Pyroxene-hornblende-quartz-plagioclase gneiss (Middle Proterozoic) at surface, covers 2 % of this area

Pyroxene-hornblende-quartz-plagioclase gneiss.

Lithology: mafic gneiss

Gabbro or norite to hornblende diorite (Upper Ordovician) at surface, covers 0.4 % of this area

Gabbro or norite to hornblende diorite - rock complex with minor pyroxenite; Croton Falls and Peach Lake complexes in New York, and Mt. Prospect Complex in Connecticut.

Lithology: gabbro; norite; diorite; pyroxenite

Rusty and gray biotite-quartz-feldspar gneiss (Middle Proterozoic) at surface, covers 0.1 % of this area

Rusty and gray biotite-quartz-feldspar gneiss - rusty facies contains variable amounts of garnet, sillimanite, cordierite, graphite, sulfides; minor marble and calcsilicate rock.

Lithology: gneiss; marble; calc-silicate rock

Hartland Formation (Ordovician?) at surface, covers 0.2 % of this area

Hartland Formation - basal amphibolite overlain by pelitic schists.

Lithology: amphibolite; pelitic schist

Diorite with hornblende and/or biotite (Upper Ordovician) at surface, covers < 0.1 % of this area

Diorite with hornblende and/or biotite.

Lithology: diorite

Garnet-biotite-quartz-feldspar gneiss (Middle Proterozoic) at surface, covers 1 % of this area

Garnet-biotite-quartz-feldspar gneiss - quartzite, quartz-feldspar gneiss, calcsilicate rock.

Lithology: gneiss; quartzite; calc-silicate rock

Inwood Marble (Early Cambrian - Lower Ordovician) at surface, covers 0.7 % of this area

Inwood Marble - dolomite marble, calc-schist, granulite, and quartzite, overlain by calcite marble; grades into underlying patchy Lowerre Quartzite of Early Cambrian age.

Lithology: marble; schist; granulite; quartzite

Calcitic and dolomitic marble (Middle Proterozoic) at surface, covers 0.4 % of this area

Calcitic and dolomitic marble - predominantly; variably siliceous; in part with calcsilicate rock and amphibolite.

Lithology: marble; calc-silicate rock; amphibolite

Amphibolite (Middle Proterozoic) at surface, covers 20 % of this area

Amphibolite - commonly biotitic; garnetiferous, pyroxenic, in and adjacent to Adirondack Highlands.

Lithology: amphibolite

Biotite-quartz-plagioclase gneiss (Middle Proterozoic) at surface, covers 26 % of this area

Biotite-quartz-plagioclase gneiss - with subordinate biotite granitic gneiss, amphibolite, calcsilicate rock.

Lithology: gneiss; granitic gneiss; amphibolite; calc-silicate rock

Poughquag Quartzite (Cambrian) at surface, covers 0.2 % of this area

Poughquag Quartzite - (includes local Dalton Formation at base)-locally conglomeratic.

Lithology: quartzite; conglomerate

Hornblende granite and granite gneiss (Middle Proterozoic) at surface, covers 1 % of this area

Hornblende granite and granite gneiss - with subordinate leucogranite.

Lithology: granite; granitic gneiss

Walloomsac Formation (Middle Ordovician) at surface, covers 2 % of this area

Walloomsac Formation - slate, phyllite, schist, metagraywacke.

Lithology: slate; phyllite; schist; metasedimentary rock

Garnet-bearing gneiss and interlayered quartzite (Middle Proterozoic) at surface, covers 12 % of this area

Garnet-bearing gneiss and interlayered quartzite - contains varying amounts of biotite, garnet, sillimanite; minor marble, amphibolite, rusty paragneiss.

Lithology: gneiss; quartzite; marble; amphibolite; paragneiss

Stockbridge Formation (Cambrian - Lower Ordovician) at surface, covers 3 % of this area

Stockbridge Formation - calcitic and dolomitic marble.

Lithology: marble

Manhattan Formation (A Member) (Middle Ordovician) at surface, covers 0.2 % of this area

Manhattan Formation (A member) - sillimanite-garnet-muscovite-biotite-quartz- plagioclase schists; calcite marble and calcsilicate rock at base.

Lithology: schist; marble; calc-silicate rock

Biotite granite gneiss (Middle Proterozoic) at surface, covers 23 % of this area

Biotite granite gneiss - overprint signifies inequigranular texture.

Lithology: granitic gneiss

Cambrian thru Middle Ordovician carbonate rock (Cambrian - Middle Ordovician) at surface, covers < 0.1 % of this area

Cambrian thru Middle Ordovician (Barneveld) carbonate rock - occuring as slivers caught along thrusts of later allochthones, or carbonate blocks in Taconic Melange.

Lithology: carbonate; melange

Manhattan Formation, undivided (Ordovician?) at surface, covers 6 % of this area

Manhattan Formation, undivided - pelitic schists, amphibolite; Units ?Omb, ?Omc, and ?Omd may be Cambrian eugeosynclinal rocks thrust upon Oma; ?Omd - sillimanite-garnet-muscovite-biotite-plagioclase-quartz gneiss; ?Omc - sillimanite-garnet-muscovite-biotite-quartz-plagioclase schistose gneiss, sillimanite nodules, local quartz-rich layers; ?Omb - discontinous unit of amphibolite and ?Omc-type schist.

Lithology: pelitic schist; gneiss; amphibolite