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["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"AR004",2040,"Ambler River","Sedimentary",100,null,null,1000]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"AR004",2038,"Ambler River","Sedimentary",1990,null,null,null]
["MzPzs","Serpentinite","Mesozoic? to Paleozoic?","Greenish-gray, yellowish-green, olive green or greenish black serpentinite, minor basaltic rocks, harzburgite tectonite, and nephrite jade exposed in the southern Ambler River and adjacent Shungnak quadrangles. In the Cosmos Hills fault-bounded serpentin",null,null,"AR004",2073,"Ambler River","Metamorphic",3498,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"AR004",2009,"Ambler River","Metamorphic",5133,null,null,null]
["KJm","Melange","Cretaceous to Jurassic","Tectonic assemblage of meter to kilometer-scale fault slivers of pillow basalt, mafic schist, metagabbro, metalimestone, metachert, metagraywacke, phyllite, and rare serpentinite exposed in low hills in the south central and southwestern part of the map","Radiolarians, conodonts",null,"AR004",2092,"Ambler River","Metamorphic",5145,null,null,null]
["DSc","Carbonate rocks of Cosmos Hills","Devonian and Silurian","Thin-bedded to massive dolostone, metalimestone, and marble, locally graphitic or phyllitic exposed in fault slices in the Cosmos Hills. Minor thin, micaceous layers interpreted as airfall tuffs, and some buff to reddish gray dolostones thought to be of","Conodonts, brachiopods, gastropods, crinoids, tabulate and rugose corals, stromatoporoids",null,"AR004",2084,"Ambler River","Metamorphic",5525,null,null,null]
["Pzp","Phyllite","Paleozoic?","Phyllite, fine-grained schist, and phyllonite of the Central belt that underlie areas of poor exposure in the northeastern Baird Mountains quadrangle, western Ambler River quadrangle, and northwestern Chandalar quadrangle.  Locally contains minor lenses",null,null,"AR004",2030,"Ambler River","Metamorphic",5560,null,null,null]
["Pzpg","Phyllite and graywacke","Paleozoic?","Dark gray to black phyllite and brown-weathering greywacke, sandstone, and mudstone exposed along the  southern boundary of the schist belt.  The unit varies in breadth along strike.  In the Wiseman and Chandalar quadrangles, two subunits are recognized:",null,null,"AR004",2007,"Ambler River","Metamorphic",5565,null,null,null]
["Pzpc","Carbonate rocks of Phyllite belt","Paleozoic","Fault-bounded blocks of marble, metalimestone, and dolostone that crop out in southwestern Ambler River quadrangle.  Carbonate rocks are locally intercalated with black phyllite, black metaquartzite, and metachert, contain megafossils (corals, brachiopod","Corals, brachiopods, crinoid debris, conodonts",null,"AR004",2086,"Ambler River","Metamorphic",5570,null,null,null]
["Mkkl","Kekiktuk Conglomerate(?), Kayak Shale of Endicott Group and Lisburne Group","Mississippian","Quartzite, conglomerate, phyllite, metalimestone, slate, dolostone, marble and chert.  Succession occurs in several fault-bounded exposures in the east-central Ambler River quadrangle.","Echinoderm debris, brachiopods, mollusks, cephalopods, and plant fragments",null,"AR004",2088,"Ambler River","Metamorphic",6305,null,null,null]
["Mc","Quartz-rich conglomerate","Mississippian?","Quartz- , chert-, quartzite-, and slate-clast conglomerate with minor thin layers of metasandstone and phyllite exposed in the Ambler River, Survey Pass, and Wiseman quadrangles.  Quartz and chert clasts are most common; chert clasts are varicolored.  Th",null,null,"AR004",2077,"Ambler River","Metamorphic",6360,null,null,null]
["Mu","Metasedimentary rocks, undivided","Mississippian","Quartz conglomerate, quartzite, metasandstone, phyllite, shale, and metalimestone in the Ambler River, Survey Pass, and Wiseman quadrangles.","Crinoids, brachiopods, corals, foraminifers, gastropods, molluscan and echinoderm debris, possible bryozoan, pelecypod, brachiopod, ostracode fragments, foraminifers",null,"AR004",2062,"Ambler River","Metamorphic",6365,null,null,null]
["Spl","Black phyllite and metalimestone","Silurian","Black siliceous phyllite and metalimestone, metasandstone, metasiltstone, phyllite, and graphitic calcareous schist in the eastern Ambler River and western Survey Pass quandrangles.  This unit is part of the Central belt.  Mapped as units Dbl and Db by M","Conodonts, graptolites, radiolarians; corals, gastropods, bryozoans, brachiopods, conularids, and orthocone cephalopods",null,"AR004",2049,"Ambler River","Metamorphic",6686,null,null,null]
["Dn","Noatak Sandstone","Devonian","Consists of metasandstone and metasiltstone with subordinate interlayers of green, gray, and maroon phyllite and local ironstone concretions. Semischistose textures and minerals indicative of lower greenschist facies metamorphism occur locally, but origi","Late Devonian (some Famennian)conodonts, brachiopods, echinoderms, gastropods, pelecypods, plant debris, and trace fossils",null,"AR004",2056,"Ambler River","Metamorphic",6900,null,null,null]
["MDk","Kanuyut Conglomerate","Lower Mississippian? and Upper Devonian","Quartzite, pebbly quartzite, conglomerte, and minor siltstone.  Exposed in a few small areas of northwestern Baird Mountains quadrangle, northeastern Ambler River quadrangle, and widely distributed in northern Survey Pass quadrangle. Semischistose and my","Echinoderm debris, brachiopods, mollusks, cephalopods, and plant fragments",null,"AR004",2028,"Ambler River","Metamorphic",6915,null,null,null]
["Dhf","Hunt Fork Shale","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"AR004",2018,"Ambler River","Metamorphic",6925,null,null,null]
["Dmu","Metasedimentary and lesser metaigneous rocks","Middle and Late Devonian","Heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt. Includes significant expanses of rocks mapped as Beaucoup Formation by some workers. T","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","AR004",2017,"Ambler River","Metamorphic",6927,null,null,null]
["Dmu_542","Metasedimentary and lesser metaigneous rocks, calcareous, iron-rich components","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt.  This part of the unit contains a light brown, gray, and orange-weathering fer","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","AR004",2052,"Ambler River","Metamorphic",6972,null,null,null]
["Dmu_541","Metasedimentary and lesser metaigneous rocks, volcanic-rock bearing subunit","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt, thought to be correlative with the Beaucoup Formation.   This subunit  contain","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from a foliated felsic rock","AR004",2043,"Ambler River","Metamorphic",6973,null,null,null]
["DOc","Younger carbonate rocks of the Nanielik Antiform, Central belt and part of Northern Thrust Assemblages","Middle Devonian to Ordovician","Very light- to dark-gray- (locally orange-) weathering, gray to black, commonly massive dolostone and lesser metalimestone and marble exposed in the northeastern Baird Mountains quadrangle in the Nanielik antiform and in the northwestern Chandalar quadra","Conodonts, corals, stromatoporoids",null,"AR004",2016,"Ambler River","Metamorphic",6980,null,null,null]
["Pzm","Marble","Paleozoic","White to gray (less commonly black), fine to coarsely crystalline, massive to platy marble and subordinate metalimestone and dolostone occurs discontinuously in all quadrangles within the map area.  This unit is part of the Central belt.","Conodonts, silicified two-hole crinoid columnals of late Early-early Middle Devonian  (late Emsian-Eifelian) age; brachiopods; possible stromatoporoids; pelmatozoan; trilobites",null,"AR004",2023,"Ambler River","Metamorphic",6983,null,null,null]
["Pzsg","Mafic schist","Paleozoic","Green and greenish-gray schistose to massive irregularly-shaped bodies and lenses of mafic rocks in units Dsq and DPsc large enough to show at the scale of the map occur in the Survey Pass and Chandalar quadrangles.  This unit is part of the Schist belt.",null,null,"AR004",2006,"Ambler River","Metamorphic",7000,null,null,null]
["Pzsm","Marble of the Schist belt","Paleozoic","Metacarbonate rocks that form an elongate belt in the central Ambler River quadrangle and are the only mappable occurrence of carbonate strata in the Schist belt. Unit surrounds the Redstone pluton and includes a variety of rock types. White, gray, and b","Conodonts, corals, stromatoporoids, spines, and echinoderm debris",null,"AR004",2087,"Ambler River","Metamorphic",7215,null,null,null]
["Dhf_101","Hunt Fork Shale - foliated exposures","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"AR004",2044,"Ambler River","Metamorphic",7225,null,null,null]
["Pzb","Black phyllite and siliceous phyllite","Paleozoic?","Gray to dark gray carbonaceous phyllite, locally silica rich, exposed in the Central belt in the western Ambler River quadrangle.  This unit is part of the Central belt.",null,null,"AR004",2066,"Ambler River","Metamorphic",7235,null,null,null]
["Dg","Granitic orthogneiss","Devonian","Tan to gray weathering, equigranular to porphyroblastic, fine to coarse grained metagranitic bodies ranging in size from less than a kilometer to over 20 kms across, found in both the Schist and Central belts.  Generally granitic in composition and made",null,"U-Pb zircon dates for orthogneiss 390-396 Ma; 375-395 Ma for orthogneiss at Mt. Igikpak","AR004",2003,"Ambler River","Metamorphic",7250,null,null,null]
["Da","Ambler sequence","Devonian","Interlayered white to medium gray weathering metarhyolite, dark green weathering metabasite, pale gray weathering marble, and brown to dark gray weathering calcareous, pelitic and carbonaceous schist exposed in two areas in the Schist belt. \"Metarhyolite","One conodont of Devonian age","U-Pb zircon ages from metarhyolite layers 378-386 Ma, bimodal igneous zircon population about 378 and 405 Ma from Arctic deposit.","AR004",2004,"Ambler River","Metamorphic",7260,null,null,null]
["OPc","Older carbonate rocks of the Central belt","Middle Ordovician to Proterozoic?","Dolostone, metalimestone, marble and subordinate quartzose metasedimentary rocks, carbonate conglomerate, and metabasite exposed in the northeastern Baird Mountains quadrangle, central Survey Pass quadrangle, and along the Dalton Highway in the Wiseman a","Conodonts, stromatolites, protoconodonts, chancellorid sclerites, hyolithids, and steinkerns of monoplacophoran mollusks, acrotretid brachiopods,agnostid arthropods, graptolites",null,"AR004",2015,"Ambler River","Metamorphic",7740,null,null,null]
["Pzbq","Black quartzite","Paleozoic?","Black weathering, fine to medium grained black metaquartzite exposed in the western Schist belt along the contact between units Dsq and DPsc.   May contain small amounts of mica and show segregation of quartz and graphite in layers parallel to foliation.",null,null,"AR004",2065,"Ambler River","Metamorphic",8602,null,null,null]
["Dsq","Quartz-mica schist","Devonian","Gray, dark gray, or brownish-gray weathering, dominantly pelitic or semipelitic schist that constitutes a major unit along the length of the Schist belt.  Outcrops vary from blocky and resistant (quartz-rich varieties) to platy and less resistant (mica-r",null,"Youngest detrital zircon population at one locality 370-360 Ma","AR004",2000,"Ambler River","Metamorphic",8602,null,null,null]
["PzZqs","Quartz-rich metasedimentary rocks","Paleozoic to Proterozoic?","Relatively homogeneous assemblage dominated by light greenish-gray fine-grained quartz-rich schist, typically accompanied by minor layers of metaconglomerate, marble, and calcareous schist.  Exposed in the southern Central belt in the western Survey Pass","Conodont",null,"AR004",2021,"Ambler River","Metamorphic",8603,null,null,null]
["DpCsc","Calcareous schist, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"AR004",2001,"Ambler River","Metamorphic",8605,null,null,null]
["DpCsc_541","Calcareous schist - albite-rich subunit, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"AR004",2063,"Ambler River","Metamorphic",8607,null,null,null]
["PzZcm","Metasedimentary and metavolcanic rocks, undivided","Paleozoic and Proterozoic?","Heterogeneous assemblage of interlayered calcareous, mafic, and siliceous rocks exposed in the central Baird Mountains, Ambler River, and Wiseman quadrangles.  This unit is part of the Central belt.","Conodonts",null,"AR004",2046,"Ambler River","Metamorphic",8655,null,null,null]
["PzZm","Mafic schist","Proterozoic? to Paleozoic?","Dark green weathering foliated mafic schist exposed in one area on the boundary between the Ambler River and Survey Pass quadrangles. This unit is part of the Central belt.",null,null,"AR004",2047,"Ambler River","Metamorphic",8661,null,null,null]
["pCam","Metamorphic rocks of Mt. Angayukaqsraq","Proterozoic","Amphibolite, metaquartzite, calcareous schist, metapelite, and a few small bodies of metagranite and metagabbro, exposed in the northeastern Baird Mountains quadrangle around Mt. Angayukaqsraq, in the south central Baird Mountains quadrangle near the Kob",null,"40Ar/39Ar  - 680 Ma metamorphic age, overprinting event - 40Ar/39Ar age of 120 Ma","AR004",2013,"Ambler River","Metamorphic",9300,null,null,null]
["pCam_572","Metamorphic rocks of Mt. Angayukaqsraq, remetamorphosed","Proterozoic","Amphibolite, metaquartzite, calcareous schist, metapelite, and a few small bodies of metagranite and metagabbro, originally metamorphosed at amphibolite-facies rocks and overprinted by an albite epidote amphibolite facies event.  Mafic outcrops in these",null,"40Ar/39Ar  - 680 Ma metamorphic age, overprinting event - 40Ar/39Ar age of 120 Ma","AR004",2068,"Ambler River","Metamorphic",9300,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"BM004",2040,"Baird Mountains","Sedimentary",100,null,null,1000]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"BM004",2038,"Baird Mountains","Sedimentary",1990,null,null,null]
["MzDm","Igneous and sedimentary rocks of the Maiyumerak Mountains","Cretaceous? to Devonian","Basalt, limestone, and two belts of melange exposed in the northwesternmost part of the map area.  This unit is part of the Maiyumerak sequence.","Conodonts and megafossils",null,"BM004",2076,"Baird Mountains","Tectonite",4951,null,null,null]
["JDk","Rocks of the Kivivik Creek sequence","Jurassic to Devonian","Consists, in ascending order, of Devonian marine sedimentary rocks equivalent to unit Dmu, sandstone, conglomerate, and shale of the Endicott Group (Devonian and Mississippian), limestone and tuff (Mississippian), chert and phyllite (Carboniferous), and","Conodonts, brachiopods and mollusks, foraminifers; radiolarian ghosts",null,"BM004",2075,"Baird Mountains","Metamorphic",5001,null,null,null]
["KJm","Melange","Cretaceous to Jurassic","Tectonic assemblage of meter to kilometer-scale fault slivers of pillow basalt, mafic schist, metagabbro, metalimestone, metachert, metagraywacke, phyllite, and rare serpentinite exposed in low hills in the south central and southwestern part of the map","Radiolarians, conodonts",null,"BM004",2092,"Baird Mountains","Metamorphic",5145,null,null,null]
["Pzp","Phyllite","Paleozoic?","Phyllite, fine-grained schist, and phyllonite of the Central belt that underlie areas of poor exposure in the northeastern Baird Mountains quadrangle, western Ambler River quadrangle, and northwestern Chandalar quadrangle.  Locally contains minor lenses",null,null,"BM004",2030,"Baird Mountains","Metamorphic",5560,null,null,null]
["Pzpg","Phyllite and graywacke","Paleozoic?","Dark gray to black phyllite and brown-weathering greywacke, sandstone, and mudstone exposed along the  southern boundary of the schist belt.  The unit varies in breadth along strike.  In the Wiseman and Chandalar quadrangles, two subunits are recognized:",null,null,"BM004",2007,"Baird Mountains","Metamorphic",5565,null,null,null]
["Mcp","Carbonaceous chert and siliceous phyllite","Mississippian","Black carbonaceous metachert and siliceous phyllite exposed in a small area in the northwestern Baird Mountains quadrangle. Massive iron sulfide intervals with elevated silver and other metal values have been documented.","conodonts, Devonian-Mississippian",null,"BM004",2071,"Baird Mountains","Metamorphic",6200,null,null,null]
["MDe","Endicott Group, undivided","Mississippian and Devonian","Shale and sandstone exposed in the northwest Baird Mountains quadrangle.  Represents undifferentiated parts equivalent the Hunt Fork Shale (unit Dhf), the Noatak Sandstone (unit Dn) and the Mississippian Kayak Shale (part of unit Mkl).",null,null,"BM004",2074,"Baird Mountains","Sedimentary",6300,null,null,null]
["Ml","Carbonate rocks","Mississippian","Light- to medium-gray weathering, dark-gray metalimestone and dolostone with locally abundant layers and lenses of black chert; megafossils (mainly silicified) include corals and possible stromatolites exposed at one locality in the Nanielik antiform, no","Corals, stromatolites, conodonts (latest Meramecian to early Chesterian), Meramecian-early Chesterian lithostrotionid corals",null,"BM004",2027,"Baird Mountains","Metamorphic",6320,null,null,null]
["Mkl","Kayak Shale of Endicott Group and Lisburne Group","Mississippian","Phyllite or slate, siltsone, sandstone, limestone, and chert in two small exposures in the northwestern Baird Mountains quadrangle and in a larger area in the Survey Pass quadrangle.","Ostracodes, brachiopods, bryozoans, and echinoderm debris, conodonts, crinoid, bryozoan, and coralline debris, brachiopods, gastropods, sponge spicules, endothyrid foraminifers",null,"BM004",2061,"Baird Mountains","Metamorphic",6328,null,null,null]
["Dn","Noatak Sandstone","Devonian","Consists of metasandstone and metasiltstone with subordinate interlayers of green, gray, and maroon phyllite and local ironstone concretions. Semischistose textures and minerals indicative of lower greenschist facies metamorphism occur locally, but origi","Late Devonian (some Famennian)conodonts, brachiopods, echinoderms, gastropods, pelecypods, plant debris, and trace fossils",null,"BM004",2056,"Baird Mountains","Metamorphic",6900,null,null,null]
["MDk","Kanuyut Conglomerate","Lower Mississippian? and Upper Devonian","Quartzite, pebbly quartzite, conglomerte, and minor siltstone.  Exposed in a few small areas of northwestern Baird Mountains quadrangle, northeastern Ambler River quadrangle, and widely distributed in northern Survey Pass quadrangle. Semischistose and my","Echinoderm debris, brachiopods, mollusks, cephalopods, and plant fragments",null,"BM004",2028,"Baird Mountains","Metamorphic",6915,null,null,null]
["Dhf","Hunt Fork Shale","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts",null,"BM004",2018,"Baird Mountains","Metamorphic",6925,null,null,null]
["Dmu","Metasedimentary and lesser metaigneous rocks","Middle and Late Devonian","Heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt. Includes significant expanses of rocks mapped as Beaucoup Formation by some workers. T","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","BM004",2017,"Baird Mountains","Metamorphic",6927,null,null,null]
["Dl","Metalimestone","Devonian","Metalimestone and lesser metasandstone, metasiltstone, phyllite, and minor conglomerate.  Assigned in part to Beaucoup Formation by some workers. This unit is part of the Central belt.","late Middle to early Late Devonian conodonts and megafossils (solitary and colonial corals, stromatoporoids, brachiopods, and mollusks)",null,"BM004",2019,"Baird Mountains","Metamorphic",6951,null,null,null]
["Dmu_541","Metasedimentary and lesser metaigneous rocks, volcanic-rock bearing subunit","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt, thought to be correlative with the Beaucoup Formation.   This subunit  contain","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from a foliated felsic rock","BM004",2043,"Baird Mountains","Metamorphic",6973,null,null,null]
["DOb","Baird Group","Devonian to Ordovician","Beige- to orange-weathering, laminated, partly argillaceous to silty metalimestone and light- to dark-gray, flaggy-bedded to massive metalimestone, marble, and dolostone.  The unit hosts several mineral occurrences and metabasaltic rocks of unknown age t","conodonts; corals and stromatoporoids",null,"BM004",2069,"Baird Mountains","Metamorphic",6980,null,null,null]
["DOc","Younger carbonate rocks of the Nanielik Antiform, Central belt and part of Northern Thrust Assemblages","Middle Devonian to Ordovician","Very light- to dark-gray- (locally orange-) weathering, gray to black, commonly massive dolostone and lesser metalimestone and marble exposed in the northeastern Baird Mountains quadrangle in the Nanielik antiform and in the northwestern Chandalar quadra","Conodonts, corals, stromatoporoids",null,"BM004",2016,"Baird Mountains","Metamorphic",6980,null,null,null]
["MDer","Eli River sequence","Mississippian and Devonian","Dolostone, limestone, argillaceous or sandy limestone, sandstone, and limestone and dolostone with chert. This unit is part of the Eli River sequence defined by Karl and others, 1989).","Stromatoporoids, brachiopods; pelmatozoan, bryozoan, and coral fragments, foraminifers, and algae (possibly mid-Famennian); spiculitic limestone; conodonts",null,"BM004",2070,"Baird Mountains","Sedimentary",6982,null,null,null]
["Pzm","Marble","Paleozoic","White to gray (less commonly black), fine to coarsely crystalline, massive to platy marble and subordinate metalimestone and dolostone occurs discontinuously in all quadrangles within the map area.  This unit is part of the Central belt.","Conodonts, silicified two-hole crinoid columnals of late Early-early Middle Devonian  (late Emsian-Eifelian) age; brachiopods; possible stromatoporoids; pelmatozoan; trilobites",null,"BM004",2023,"Baird Mountains","Metamorphic",6983,null,null,null]
["Pzsg","Mafic schist","Paleozoic","Green and greenish-gray schistose to massive irregularly-shaped bodies and lenses of mafic rocks in units Dsq and DPsc large enough to show at the scale of the map occur in the Survey Pass and Chandalar quadrangles.  This unit is part of the Schist belt.",null,null,"BM004",2006,"Baird Mountains","Metamorphic",7000,null,null,null]
["Dhf_101","Hunt Fork Shale - foliated exposures","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"BM004",2044,"Baird Mountains","Metamorphic",7225,null,null,null]
["Pzb","Black phyllite and siliceous phyllite","Paleozoic?","Gray to dark gray carbonaceous phyllite, locally silica rich, exposed in the Central belt in the western Ambler River quadrangle.  This unit is part of the Central belt.",null,null,"BM004",2066,"Baird Mountains","Metamorphic",7235,null,null,null]
["OPc","Older carbonate rocks of the Central belt","Middle Ordovician to Proterozoic?","Dolostone, metalimestone, marble and subordinate quartzose metasedimentary rocks, carbonate conglomerate, and metabasite exposed in the northeastern Baird Mountains quadrangle, central Survey Pass quadrangle, and along the Dalton Highway in the Wiseman a","Conodonts, stromatolites, protoconodonts, chancellorid sclerites, hyolithids, and steinkerns of monoplacophoran mollusks, acrotretid brachiopods,agnostid arthropods, graptolites",null,"BM004",2015,"Baird Mountains","Metamorphic",7740,null,null,null]
["OpCc_541","Older carbonate rocks of the Central belt, restricted","Middle Ordovician to Proterozoic?","Dolostone, metalimestone, marble and subordinate quartzose metasedimentary rocks, carbonate conglomerate, and metabasite.  Only exposures that contain the Ordovician part of unit OPc are included in this unit.","Conodonts, stromatolites, protoconodonts, chancellorid sclerites, hyolithids, and steinkerns of monoplacophoran mollusks, acrotretid brachiopods,agnostid arthropods, graptolites",null,"BM004",2042,"Baird Mountains","Metamorphic",7741,null,null,null]
["Dsq","Quartz-mica schist","Devonian","Gray, dark gray, or brownish-gray weathering, dominantly pelitic or semipelitic schist that constitutes a major unit along the length of the Schist belt.  Outcrops vary from blocky and resistant (quartz-rich varieties) to platy and less resistant (mica-r",null,"Youngest detrital zircon population at one locality 370-360 Ma","BM004",2000,"Baird Mountains","Metamorphic",8602,null,null,null]
["Pzbq","Black quartzite","Paleozoic?","Black weathering, fine to medium grained black metaquartzite exposed in the western Schist belt along the contact between units Dsq and DPsc.   May contain small amounts of mica and show segregation of quartz and graphite in layers parallel to foliation.",null,null,"BM004",2065,"Baird Mountains","Metamorphic",8602,null,null,null]
["DpCsc","Calcareous schist, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"BM004",2001,"Baird Mountains","Metamorphic",8605,null,null,null]
["DpCsc_541","Calcareous schist - albite-rich subunit, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"BM004",2063,"Baird Mountains","Metamorphic",8607,null,null,null]
["PzZcm","Metasedimentary and metavolcanic rocks, undivided","Paleozoic and Proterozoic?","Heterogeneous assemblage of interlayered calcareous, mafic, and siliceous rocks exposed in the central Baird Mountains, Ambler River, and Wiseman quadrangles.  This unit is part of the Central belt.","Conodonts",null,"BM004",2046,"Baird Mountains","Metamorphic",8655,null,null,null]
["PzZg","Granitic rocks","Paleozoic to Proterozoic?","Pale gray-green, massive to gneissic granitic to dioritic orthogneiss exposed in the Schist belt in the southern Baird Mountains quadrangle. No direct age control; may be correlative with Pg.",null,null,"BM004",2067,"Baird Mountains","Metamorphic",9045,null,null,null]
["pCg","Granitic orthogneiss","Paleozoic","Metagranitic rocks of several Proterozoic ages exposed in southern Baird Mountains and western Wiseman quadrangles.",null,"U-Pb zircon ages: southern Baird Mtns quad - 705+/-35 Ma; Ernie Lake pluton  - 971+/-5 Ma; Mt. Angayukaqsraq - 750 +/- 6 Ma","BM004",2011,"Baird Mountains","Metamorphic",9060,null,null,null]
["pCam","Metamorphic rocks of Mt. Angayukaqsraq","Proterozoic","Amphibolite, metaquartzite, calcareous schist, metapelite, and a few small bodies of metagranite and metagabbro, exposed in the northeastern Baird Mountains quadrangle around Mt. Angayukaqsraq, in the south central Baird Mountains quadrangle near the Kob",null,"40Ar/39Ar  - 680 Ma metamorphic age, overprinting event - 40Ar/39Ar age of 120 Ma","BM004",2013,"Baird Mountains","Metamorphic",9300,null,null,null]
["pCam_572","Metamorphic rocks of Mt. Angayukaqsraq, remetamorphosed","Proterozoic","Amphibolite, metaquartzite, calcareous schist, metapelite, and a few small bodies of metagranite and metagabbro, originally metamorphosed at amphibolite-facies rocks and overprinted by an albite epidote amphibolite facies event.  Mafic outcrops in these",null,"40Ar/39Ar  - 680 Ma metamorphic age, overprinting event - 40Ar/39Ar age of 120 Ma","BM004",2068,"Baird Mountains","Metamorphic",9300,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"BT005",2040,"Bettles","Sedimentary",100,null,null,1000]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"BT005",2038,"Bettles","Sedimentary",1990,null,null,null]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"BT005",2038,"Bettles","Sedimentary",1990,null,null,null]
["Kvg","Volcanic-clast graywacke and mudstone","Cretaceous","Fine grained to conglomeratic greywacke and fine-grained laminated mudstone exposed along the south-central boundary of the map. Mudstone is locally tuffaceous.  Clasts are predominantly intermediate and mafic volcanic and intrusive rocks and chert with","Marine mollusks of Late Early Cretaceous (Albian) age",null,"BT005",2091,"Bettles","Sedimentary",2180,null,null,null]
["Kg","Granitic rocks","Cretaceous","Granite, quartz monzonite, and granodiorite of the northern Ruby terrane, exposed along the southern boundary of the Chandalar quadrangle.",null,"K-Ar dates from south of map area are 96-112 Ma","BT005",2037,"Bettles","Igneous",2492,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"BT005",2009,"Bettles","Metamorphic",5133,null,null,null]
["DpCm","Metamorphic rocks, Mosquito terrane","Devonian to Proterozoic?","Pelitic schist, metabasite, minor felsic orthogneiss and meta-ultramafic rock exposed in two small areas along the Kobuk fault zone in the northeast Bettles and southwest Chandalar quadrangles.  The rocks exhibit amphibolite-facies metamorphic assemblage",null,"54.8 +/- 1.3 Ma white mica cooling age","BT005",2008,"Bettles","Metamorphic",8852,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"CH004",2040,"Chandalar","Sedimentary",100,null,null,1000]
["QTb","Basalt","Quaternary? or Tertiary?","Flat-lying, vesicular  olivine basalt flows exposed in the southeast part of the Chandalar quadrangle. Thought to be about 300 meters thick.",null,null,"CH004",2039,"Chandalar","Igneous",350,null,null,3500]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"CH004",2038,"Chandalar","Sedimentary",1990,null,null,null]
["Kg","Granitic rocks","Cretaceous","Granite, quartz monzonite, and granodiorite of the northern Ruby terrane, exposed along the southern boundary of the Chandalar quadrangle.",null,"K-Ar dates from south of map area are 96-112 Ma","CH004",2037,"Chandalar","Igneous",2492,null,null,null]
["Km","Migmatite","Cretaceous","Intercalated granitic rocks, biotite schist, and hornblende hornfels; pyroxene hornfels and granitic dikes, associated with Cretaceous granitic rocks.  All exposed in the northern Ruby terrane, along the southern margin of the Chandalar quadrangle.   Inc",null,null,"CH004",2036,"Chandalar","Metamorphic",2610,null,null,null]
["Khs","Rocks of the Hammond River shear zone","Cretaceous?","Heterogeneous mix of finely laminated, mostly mylonitic lithologies derived in part from adjacent units exposed in the eastern Wiseman and western Chandalar quadrangles.  Unit is recessive, poorly exposed, and includes large (up to 0.5 km across) bodies",null,null,"CH004",2022,"Chandalar","Metamorphic",2650,null,null,null]
["TrCs","Sedimentary rocks","Triassic to Carboniferous","Quartzite, phyllite, siltstone, conglomerate, shale, sandstone, limestone, argillaceous limestone, dolomitic limestone, and cherty dolostone.  Occurs in the Mount Doonerak area in northeastern Wiseman and northwestern Chandalar quadrangles, where it is i","Conodonts; foraminifers; crinoidal packstone; burrows and trace fossils; brachiopods Wolfcampian age",null,"CH004",2026,"Chandalar","Sedimentary",5004,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"CH004",2009,"Chandalar","Metamorphic",5133,null,null,null]
["Pzp","Phyllite","Paleozoic?","Phyllite, fine-grained schist, and phyllonite of the Central belt that underlie areas of poor exposure in the northeastern Baird Mountains quadrangle, western Ambler River quadrangle, and northwestern Chandalar quadrangle.  Locally contains minor lenses",null,null,"CH004",2030,"Chandalar","Metamorphic",5560,null,null,null]
["Pzpg","Phyllite and graywacke","Paleozoic?","Dark gray to black phyllite and brown-weathering greywacke, sandstone, and mudstone exposed along the  southern boundary of the schist belt.  The unit varies in breadth along strike.  In the Wiseman and Chandalar quadrangles, two subunits are recognized:",null,null,"CH004",2007,"Chandalar","Metamorphic",5565,null,null,null]
["SCvs","Volcanic and sedimentary rocks","Silurian to Cambrian","Volcanic rocks, volcaniclastic rocks, and clastic sedimentary rocks exposed in the core of the Doonerak antiform, northeast Wiseman quadrangle.  The unit can be divided into at least two lithologic sequences, one dominated by volcanic rocks, the other by","Microfossils, brachiopods, trilobites, graptolites, conodonts","K-Ar and Ar-Ar ages of dikes 373-388 Ma and 478 Ma","CH004",2057,"Chandalar","Sedimentary",6720,null,null,null]
["Pzj","Metasedimentary rocks of Jesse Mountain","Paleozoic","Generally fine grained, phyllitic to schistose, gray-weathering meta-argillite, black-weathering metaquartzite, marble, and brown weathering impure marble, exposed in a single area in the eastern Wiseman quadrangle.   This unit is part of the Central bel","Conodonts; brachiopods; coral fragments",null,"CH004",2032,"Chandalar","Metamorphic",6850,null,null,null]
["Dhf","Hunt Fork Shale","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"CH004",2018,"Chandalar","Metamorphic",6925,null,null,null]
["Pzw","Metasedimentary rocks","Paleozoic","Weakly metamorphosed metasandstone, meta-argillite, phyllite, conglomerate, and rare marble exposed in two belts on the Wiseman/Chandalar quadangle boundary.  This subunit, the northern belt, is composed of metasandstone and argillite, and contains abund",null,"Detrital white mica -Ordovician 40Ar/39Ar cooling age","CH004",2053,"Chandalar","Metamorphic",6927,null,null,null]
["Pzw_572","Metasedimentary rocks","Paleozoic","Weakly metamorphosed metasandstone, meta-argillite, phyllite, conglomerate, and rare marble exposed in two belts on the Wiseman/Chandalar quadangle boundary.   This subunit, the southern of the two belts, is composed of phyllite, metasandstone with volca","Conodonts, bryozoans, corals",null,"CH004",2055,"Chandalar","Metamorphic",6927,null,null,null]
["Dmu","Metasedimentary and lesser metaigneous rocks","Middle and Late Devonian","Heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt. Includes significant expanses of rocks mapped as Beaucoup Formation by some workers. T","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","CH004",2017,"Chandalar","Metamorphic",6927,null,null,null]
["Dl","Metalimestone","Devonian","Metalimestone and lesser metasandstone, metasiltstone, phyllite, and minor conglomerate.  Assigned in part to Beaucoup Formation by some workers. This unit is part of the Central belt.","late Middle to early Late Devonian conodonts and megafossils (solitary and colonial corals, stromatoporoids, brachiopods, and mollusks)",null,"CH004",2019,"Chandalar","Metamorphic",6951,null,null,null]
["Dmu_541","Metasedimentary and lesser metaigneous rocks, volcanic-rock bearing subunit","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt, thought to be correlative with the Beaucoup Formation.   This subunit  contain","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from a foliated felsic rock","CH004",2043,"Chandalar","Metamorphic",6973,null,null,null]
["DOc","Younger carbonate rocks of the Nanielik Antiform, Central belt and part of Northern Thrust Assemblages","Middle Devonian to Ordovician","Very light- to dark-gray- (locally orange-) weathering, gray to black, commonly massive dolostone and lesser metalimestone and marble exposed in the northeastern Baird Mountains quadrangle in the Nanielik antiform and in the northwestern Chandalar quadra","Conodonts, corals, stromatoporoids",null,"CH004",2016,"Chandalar","Metamorphic",6980,null,null,null]
["Pzm","Marble","Paleozoic","White to gray (less commonly black), fine to coarsely crystalline, massive to platy marble and subordinate metalimestone and dolostone occurs discontinuously in all quadrangles within the map area.  This unit is part of the Central belt.","Conodonts, silicified two-hole crinoid columnals of late Early-early Middle Devonian  (late Emsian-Eifelian) age; brachiopods; possible stromatoporoids; pelmatozoan; trilobites",null,"CH004",2023,"Chandalar","Metamorphic",6983,null,null,null]
["Pzsg","Mafic schist","Paleozoic","Green and greenish-gray schistose to massive irregularly-shaped bodies and lenses of mafic rocks in units Dsq and DPsc large enough to show at the scale of the map occur in the Survey Pass and Chandalar quadrangles.  This unit is part of the Schist belt.",null,null,"CH004",2006,"Chandalar","Metamorphic",7000,null,null,null]
["Dps_101","Wacke and lesser amounts of shale - schistose","Devonian","Schistose varieties of gray-green lithic wacke, lesser brown quartz wacke, and black shale and silty shale exposed in the eastern map area. This unit is part of the Phyllite belt.",null,null,"CH004",2083,"Chandalar","Metamorphic",7200,null,null,null]
["Dhf_101","Hunt Fork Shale - foliated exposures","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"CH004",2044,"Chandalar","Metamorphic",7225,null,null,null]
["Dg","Granitic orthogneiss","Devonian","Tan to gray weathering, equigranular to porphyroblastic, fine to coarse grained metagranitic bodies ranging in size from less than a kilometer to over 20 kms across, found in both the Schist and Central belts.  Generally granitic in composition and made",null,"U-Pb zircon dates for orthogneiss 390-396 Ma; 375-395 Ma for orthogneiss at Mt. Igikpak","CH004",2003,"Chandalar","Metamorphic",7250,null,null,null]
["OpCc","Older carbonate rocks of the Central belt","Middle Ordovician to Proterozoic?","Dolostone, metalimestone, marble and subordinate quartzose metasedimentary rocks, carbonate conglomerate, and metabasite exposed in the northeastern Baird Mountains quadrangle, central Survey Pass quadrangle, and along the Dalton Highway in the Wiseman a","Conodonts, stromatolites, protoconodonts, chancellorid sclerites, hyolithids, and steinkerns of monoplacophoran mollusks, acrotretid brachiopods,agnostid arthropods, graptolites",null,"CH004",2015,"Chandalar","Metamorphic",7740,null,null,null]
["OpCc_541","Older carbonate rocks of the Central belt, restricted","Middle Ordovician to Proterozoic?","Dolostone, metalimestone, marble and subordinate quartzose metasedimentary rocks, carbonate conglomerate, and metabasite.  Only exposures that contain the Ordovician part of unit OPc are included in this unit.","Conodonts, stromatolites, protoconodonts, chancellorid sclerites, hyolithids, and steinkerns of monoplacophoran mollusks, acrotretid brachiopods,agnostid arthropods, graptolites",null,"CH004",2042,"Chandalar","Metamorphic",7741,null,null,null]
["PzZbs","Biotite schist","Paleozoic to Proterozoic?","Quartz-albite-oligoclase-biotite schist with staurolite and andalusite exposed in the southeastern Chandalar quadrangle, adjacent to rocks of the Schist belt.  Age of metamorphism not known. This unit is part of the Ruby terrane.",null,null,"CH004",2034,"Chandalar","Metamorphic",8601,null,null,null]
["Dsq","Quartz-mica schist","Devonian","Gray, dark gray, or brownish-gray weathering, dominantly pelitic or semipelitic schist that constitutes a major unit along the length of the Schist belt.  Outcrops vary from blocky and resistant (quartz-rich varieties) to platy and less resistant (mica-r",null,"Youngest detrital zircon population at one locality 370-360 Ma","CH004",2000,"Chandalar","Metamorphic",8602,null,null,null]
["PzZqs","Quartz-rich metasedimentary rocks","Paleozoic to Proterozoic?","Relatively homogeneous assemblage dominated by light greenish-gray fine-grained quartz-rich schist, typically accompanied by minor layers of metaconglomerate, marble, and calcareous schist.  Exposed in the southern Central belt in the western Survey Pass","Conodont",null,"CH004",2021,"Chandalar","Metamorphic",8603,null,null,null]
["DpCsc","Calcareous schist, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"CH004",2001,"Chandalar","Metamorphic",8605,null,null,null]
["DpCsc_101","Calcareous schist - metachert and conglomerate subunit, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"CH004",2041,"Chandalar","Metamorphic",8608,null,null,null]
["DpCm","Metamorphic rocks, Mosquito terrane","Devonian to Proterozoic?","Pelitic schist, metabasite, minor felsic orthogneiss and meta-ultramafic rock exposed in two small areas along the Kobuk fault zone in the northeast Bettles and southwest Chandalar quadrangles.  The rocks exhibit amphibolite-facies metamorphic assemblage",null,"54.8 +/- 1.3 Ma white mica cooling age","CH004",2008,"Chandalar","Metamorphic",8852,null,null,null]
["PzZsr","Ruby schist","Paleozoic to Proterozoic?","Biotite-bearing pelitic schist with subordinate metaquartzite, exposed in the southern Wiseman quadrangle.  Equivalent to schists of the Ruby geanticline, south of the map area, where the earliest documented metamorphic event to affect the schists was bl",null,null,"CH004",2035,"Chandalar","Metamorphic",9325,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"CS004",2040,"Christian","Sedimentary",100,null,null,1000]
["Kg","Granitic rocks","Cretaceous","Granite, quartz monzonite, and granodiorite of the northern Ruby terrane, exposed along the southern boundary of the Chandalar quadrangle.",null,"K-Ar dates from south of map area are 96-112 Ma","CS004",2037,"Christian","Igneous",2492,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"CS004",2009,"Christian","Metamorphic",5133,null,null,null]
["Dps","Wacke and lesser amounts of shale","Devonian","Dominantly gray-green lithic wacke, lesser brown quartz wacke, and black shale and silty shale exposed in the eastern map area. Wackes are fine- to medium-grained and thin to  medium-bedded.  Black shale forms up to 50 percent of the unit and occurs in l",null,null,"CS004",2083,"Christian","Sedimentary",6900,null,null,null]
["Dmu","Metasedimentary and lesser metaigneous rocks","Middle and Late Devonian","Heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt. Includes significant expanses of rocks mapped as Beaucoup Formation by some workers. T","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","CS004",2017,"Christian","Metamorphic",6927,null,null,null]
["Dl","Metalimestone","Devonian","Metalimestone and lesser metasandstone, metasiltstone, phyllite, and minor conglomerate.  Assigned in part to Beaucoup Formation by some workers. This unit is part of the Central belt.","late Middle to early Late Devonian conodonts and megafossils (solitary and colonial corals, stromatoporoids, brachiopods, and mollusks)",null,"CS004",2019,"Christian","Metamorphic",6951,null,null,null]
["Dmu_541","Metasedimentary and lesser metaigneous rocks, volcanic-rock bearing subunit","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt, thought to be correlative with the Beaucoup Formation.   This subunit  contain","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from a foliated felsic rock","CS004",2043,"Christian","Metamorphic",6973,null,null,null]
["Pzm","Marble","Paleozoic","White to gray (less commonly black), fine to coarsely crystalline, massive to platy marble and subordinate metalimestone and dolostone occurs discontinuously in all quadrangles within the map area.  This unit is part of the Central belt.","Conodonts, silicified two-hole crinoid columnals of late Early-early Middle Devonian  (late Emsian-Eifelian) age; brachiopods; possible stromatoporoids; pelmatozoan; trilobites",null,"CS004",2023,"Christian","Metamorphic",6983,null,null,null]
["Dps_101","Wacke and lesser amounts of shale - schistose","Devonian","Schistose varieties of gray-green lithic wacke, lesser brown quartz wacke, and black shale and silty shale exposed in the eastern map area. This unit is part of the Phyllite belt.",null,null,"CS004",2083,"Christian","Metamorphic",7200,null,null,null]
["Dhf_101","Hunt Fork Shale - foliated exposures","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"CS004",2044,"Christian","Metamorphic",7225,null,null,null]
["PzZbs","Biotite schist","Paleozoic to Proterozoic?","Quartz-albite-oligoclase-biotite schist with staurolite and andalusite exposed in the southeastern Chandalar quadrangle, adjacent to rocks of the Schist belt.  Age of metamorphism not known. This unit is part of the Ruby terrane.",null,null,"CS004",2034,"Christian","Metamorphic",8601,null,null,null]
["Dsq","Quartz-mica schist","Devonian","Gray, dark gray, or brownish-gray weathering, dominantly pelitic or semipelitic schist that constitutes a major unit along the length of the Schist belt.  Outcrops vary from blocky and resistant (quartz-rich varieties) to platy and less resistant (mica-r",null,"Youngest detrital zircon population at one locality 370-360 Ma","CS004",2000,"Christian","Metamorphic",8602,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"HU004",2040,"Hughes","Sedimentary",100,null,null,1000]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"HU004",2038,"Hughes","Sedimentary",1990,null,null,null]
["Kvg","Volcanic-clast graywacke and mudstone","Cretaceous","Fine grained to conglomeratic greywacke and fine-grained laminated mudstone exposed along the south-central boundary of the map. Mudstone is locally tuffaceous.  Clasts are predominantly intermediate and mafic volcanic and intrusive rocks and chert with","Marine mollusks of Late Early Cretaceous (Albian) age",null,"HU004",2091,"Hughes","Sedimentary",2180,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"HU004",2009,"Hughes","Metamorphic",5133,null,null,null]
["KJm","Melange","Cretaceous to Jurassic","Tectonic assemblage of meter to kilometer-scale fault slivers of pillow basalt, mafic schist, metagabbro, metalimestone, metachert, metagraywacke, phyllite, and rare serpentinite exposed in low hills in the south central and southwestern part of the map","Radiolarians, conodonts",null,"HU004",2092,"Hughes","Metamorphic",5145,null,null,null]
["Pzpg","Phyllite and graywacke","Paleozoic?","Dark gray to black phyllite and brown-weathering greywacke, sandstone, and mudstone exposed along the  southern boundary of the schist belt.  The unit varies in breadth along strike.  In the Wiseman and Chandalar quadrangles, two subunits are recognized:",null,null,"HU004",2007,"Hughes","Metamorphic",5565,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"SE005",2040,"Selawik","Sedimentary",100,null,null,1000]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"SE005",2038,"Selawik","Sedimentary",1990,null,null,null]
["Pzm","Marble","Paleozoic","White to gray (less commonly black), fine to coarsely crystalline, massive to platy marble and subordinate metalimestone and dolostone occurs discontinuously in all quadrangles within the map area.  This unit is part of the Central belt.","Conodonts, silicified two-hole crinoid columnals of late Early-early Middle Devonian  (late Emsian-Eifelian) age; brachiopods; possible stromatoporoids; pelmatozoan; trilobites",null,"SE005",2023,"Selawik","Metamorphic",6983,null,null,null]
["Pzsg","Mafic schist","Paleozoic","Green and greenish-gray schistose to massive irregularly-shaped bodies and lenses of mafic rocks in units Dsq and DPsc large enough to show at the scale of the map occur in the Survey Pass and Chandalar quadrangles.  This unit is part of the Schist belt.",null,null,"SE005",2006,"Selawik","Metamorphic",7000,null,null,null]
["Dsq","Quartz-mica schist","Devonian","Gray, dark gray, or brownish-gray weathering, dominantly pelitic or semipelitic schist that constitutes a major unit along the length of the Schist belt.  Outcrops vary from blocky and resistant (quartz-rich varieties) to platy and less resistant (mica-r",null,"Youngest detrital zircon population at one locality 370-360 Ma","SE005",2000,"Selawik","Metamorphic",8602,null,null,null]
["DpCsc","Calcareous schist, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"SE005",2001,"Selawik","Metamorphic",8605,null,null,null]
["PzZcm","Metasedimentary and metavolcanic rocks, undivided","Paleozoic and Proterozoic?","Heterogeneous assemblage of interlayered calcareous, mafic, and siliceous rocks exposed in the central Baird Mountains, Ambler River, and Wiseman quadrangles.  This unit is part of the Central belt.","Conodonts",null,"SE005",2046,"Selawik","Metamorphic",8655,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"SH005",2040,"Shungnak","Sedimentary",100,null,null,1000]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"SH005",2038,"Shungnak","Sedimentary",1990,null,null,null]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"SH005",2038,"Shungnak","Sedimentary",1990,null,null,null]
["Kvg","Volcanic-clast graywacke and mudstone","Cretaceous","Fine grained to conglomeratic greywacke and fine-grained laminated mudstone exposed along the south-central boundary of the map. Mudstone is locally tuffaceous.  Clasts are predominantly intermediate and mafic volcanic and intrusive rocks and chert with","Marine mollusks of Late Early Cretaceous (Albian) age",null,"SH005",2091,"Shungnak","Sedimentary",2180,null,null,null]
["MzPzs","Serpentinite","Mesozoic? to Paleozoic?","Greenish-gray, yellowish-green, olive green or greenish black serpentinite, minor basaltic rocks, harzburgite tectonite, and nephrite jade exposed in the southern Ambler River and adjacent Shungnak quadrangles. In the Cosmos Hills fault-bounded serpentin",null,null,"SH005",2073,"Shungnak","Metamorphic",3498,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"SH005",2009,"Shungnak","Metamorphic",5133,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"SH005",2009,"Shungnak","Metamorphic",5133,null,null,null]
["KJm","Melange","Cretaceous to Jurassic","Tectonic assemblage of meter to kilometer-scale fault slivers of pillow basalt, mafic schist, metagabbro, metalimestone, metachert, metagraywacke, phyllite, and rare serpentinite exposed in low hills in the south central and southwestern part of the map","Radiolarians, conodonts",null,"SH005",2092,"Shungnak","Metamorphic",5145,null,null,null]
["DSc","Carbonate rocks of Cosmos Hills","Devonian and Silurian","Thin-bedded to massive dolostone, metalimestone, and marble, locally graphitic or phyllitic exposed in fault slices in the Cosmos Hills. Minor thin, micaceous layers interpreted as airfall tuffs, and some buff to reddish gray dolostones thought to be of","Conodonts, brachiopods, gastropods, crinoids, tabulate and rugose corals, stromatoporoids",null,"SH005",2084,"Shungnak","Metamorphic",6927,null,null,null]
["Dg","Granitic orthogneiss","Devonian","Tan to gray weathering, equigranular to porphyroblastic, fine to coarse grained metagranitic bodies ranging in size from less than a kilometer to over 20 kms across, found in both the Schist and Central belts.  Generally granitic in composition and made",null,"U-Pb zircon dates for orthogneiss 390-396 Ma; 375-395 Ma for orthogneiss at Mt. Igikpak","SH005",2003,"Shungnak","Metamorphic",7250,null,null,null]
["Dsq","Quartz-mica schist","Devonian","Gray, dark gray, or brownish-gray weathering, dominantly pelitic or semipelitic schist that constitutes a major unit along the length of the Schist belt.  Outcrops vary from blocky and resistant (quartz-rich varieties) to platy and less resistant (mica-r",null,"Youngest detrital zircon population at one locality 370-360 Ma","SH005",2000,"Shungnak","Metamorphic",8602,null,null,null]
["DpCsc","Calcareous schist, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"SH005",2001,"Shungnak","Metamorphic",8605,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"SP004",2040,"Survey Pass","Sedimentary",100,null,null,1000]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"SP004",2038,"Survey Pass","Sedimentary",1990,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"SP004",2009,"Survey Pass","Metamorphic",5133,null,null,null]
["KJm","Melange","Cretaceous to Jurassic","Tectonic assemblage of meter to kilometer-scale fault slivers of pillow basalt, mafic schist, metagabbro, metalimestone, metachert, metagraywacke, phyllite, and rare serpentinite exposed in low hills in the south central and southwestern part of the map","Radiolarians, conodonts",null,"SP004",2092,"Survey Pass","Metamorphic",5145,null,null,null]
["Pzpg","Phyllite and graywacke","Paleozoic?","Dark gray to black phyllite and brown-weathering greywacke, sandstone, and mudstone exposed along the  southern boundary of the schist belt.  The unit varies in breadth along strike.  In the Wiseman and Chandalar quadrangles, two subunits are recognized:",null,null,"SP004",2007,"Survey Pass","Metamorphic",5565,null,null,null]
["Pzpg","Phyllite and graywacke","Paleozoic?","Dark gray to black phyllite and brown-weathering greywacke, sandstone, and mudstone exposed along the  southern boundary of the schist belt.  The unit varies in breadth along strike.  In the Wiseman and Chandalar quadrangles, two subunits are recognized:",null,null,"SP004",2007,"Survey Pass","Metamorphic",5565,null,null,null]
["Mkl","Kayak Shale of Endicott Group and Lisburne Group","Mississippian","Phyllite or slate, siltsone, sandstone, limestone, and chert in two small exposures in the northwestern Baird Mountains quadrangle and in a larger area in the Survey Pass quadrangle.","Ostracodes, brachiopods, bryozoans, and echinoderm debris, conodonts, crinoid, bryozoan, and coralline debris, brachiopods, gastropods, sponge spicules, endothyrid foraminifers",null,"SP004",2061,"Survey Pass","Metamorphic",6328,null,null,null]
["Pzbs","Black metasedimentary rocks","Paleozoic","Dark gray to black phyllite and calcareous phyllite with dark gray to orange-weathering marble and dolostone layers up to 50 m thick, exposed in the northeastern Survey Pass and northwestern Wiseman quadrangles.   This unit is part of the Central belt.","Brachiopods  - Middle Devonian or Frasnian (early Late Devonian)",null,"SP004",2085,"Survey Pass","Metamorphic",6331,null,null,null]
["Mc","Quartz-rich conglomerate","Mississippian?","Quartz- , chert-, quartzite-, and slate-clast conglomerate with minor thin layers of metasandstone and phyllite exposed in the Ambler River, Survey Pass, and Wiseman quadrangles.  Quartz and chert clasts are most common; chert clasts are varicolored.  Th",null,null,"SP004",2077,"Survey Pass","Metamorphic",6360,null,null,null]
["Mu","Metasedimentary rocks, undivided","Mississippian","Quartz conglomerate, quartzite, metasandstone, phyllite, shale, and metalimestone in the Ambler River, Survey Pass, and Wiseman quadrangles.","Crinoids, brachiopods, corals, foraminifers, gastropods, molluscan and echinoderm debris, possible bryozoan, pelecypod, brachiopod, ostracode fragments, foraminifers",null,"SP004",2062,"Survey Pass","Metamorphic",6365,null,null,null]
["Spl","Black phyllite and metalimestone","Silurian","Black siliceous phyllite and metalimestone, metasandstone, metasiltstone, phyllite, and graphitic calcareous schist in the eastern Ambler River and western Survey Pass quandrangles.  This unit is part of the Central belt.  Originally mapped as the wester","Conodonts, graptolites, radiolarians; corals, gastropods, bryozoans, brachiopods, conularids, and orthocone cephalopods",null,"SP004",2049,"Survey Pass","Metamorphic",6686,null,null,null]
["Dn","Noatak Sandstone","Devonian","Consists of metasandstone and metasiltstone with subordinate interlayers of green, gray, and maroon phyllite and local ironstone concretions. Semischistose textures and minerals indicative of lower greenschist facies metamorphism occur locally, but origi","Late Devonian (some Famennian)conodonts, brachiopods, echinoderms, gastropods, pelecypods, plant debris, and trace fossils",null,"SP004",2056,"Survey Pass","Metamorphic",6900,null,null,null]
["MDk_101","Kanuyut Conglomerate and Noatak Sandstone","Lower Mississippian? and Upper Devonian","Quartzite, pebbly quartzite, conglomerate, and minor siltstone. This unit includes exposures where Kanayut has not been differentiated from Noatak Sandstone.","Echinoderm debris, brachiopods, mollusks, cephalopods, and plant fragments",null,"SP004",2089,"Survey Pass","Metamorphic",6914,null,null,null]
["MDk","Kanuyut Conglomerate","Lower Mississippian? and Upper Devonian","Quartzite, pebbly quartzite, conglomerte, and minor siltstone.  Exposed in a few small areas of northwestern Baird Mountains quadrangle, northeastern Ambler River quadrangle, and widely distributed in northern Survey Pass quadrangle. Semischistose and my","Echinoderm debris, brachiopods, mollusks, cephalopods, and plant fragments",null,"SP004",2028,"Survey Pass","Metamorphic",6915,null,null,null]
["Dhf","Hunt Fork Shale","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"SP004",2018,"Survey Pass","Metamorphic",6925,null,null,null]
["Dmu","Metasedimentary and lesser metaigneous rocks","Middle and Late Devonian","Heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt. Includes significant expanses of rocks mapped as Beaucoup Formation by some workers. T","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","SP004",2017,"Survey Pass","Metamorphic",6927,null,null,null]
["Dmu_542","Metasedimentary and lesser metaigneous rocks, calcareous, iron-rich components","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt.  This part of the unit contains a light brown, gray, and orange-weathering fer","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","SP004",2052,"Survey Pass","Metamorphic",6972,null,null,null]
["Dmu_541","Metasedimentary and lesser metaigneous rocks, volcanic-rock bearing subunit","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt, thought to be correlative with the Beaucoup Formation.   This subunit  contain","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from a foliated felsic rock","SP004",2043,"Survey Pass","Metamorphic",6973,null,null,null]
["Pzm","Marble","Paleozoic","White to gray (less commonly black), fine to coarsely crystalline, massive to platy marble and subordinate metalimestone and dolostone occurs discontinuously in all quadrangles within the map area.  This unit is part of the Central belt.","Conodonts, silicified two-hole crinoid columnals of late Early-early Middle Devonian  (late Emsian-Eifelian) age; brachiopods; possible stromatoporoids; pelmatozoan; trilobites",null,"SP004",2023,"Survey Pass","Metamorphic",6983,null,null,null]
["Pzsg","Mafic schist","Paleozoic","Green and greenish-gray schistose to massive irregularly-shaped bodies and lenses of mafic rocks in units Dsq and DPsc large enough to show at the scale of the map occur in the Survey Pass and Chandalar quadrangles.  This unit is part of the Schist belt.",null,null,"SP004",2006,"Survey Pass","Metamorphic",7000,null,null,null]
["Dhf_101","Hunt Fork Shale - foliated exposures","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"SP004",2044,"Survey Pass","Metamorphic",7225,null,null,null]
["Dg","Granitic orthogneiss","Devonian","Tan to gray weathering, equigranular to porphyroblastic, fine to coarse grained metagranitic bodies ranging in size from less than a kilometer to over 20 kms across, found in both the Schist and Central belts.  Generally granitic in composition and made",null,"U-Pb zircon dates for orthogneiss 390-396 Ma; 375-395 Ma for orthogneiss at Mt. Igikpak","SP004",2003,"Survey Pass","Metamorphic",7250,null,null,null]
["Da","Amber sequence","Devonian","Interlayered white to medium gray weathering metarhyolite, dark green weathering metabasite, pale gray weathering marble, and brown to dark gray weathering calcareous, pelitic and carbonaceous schist exposed in two areas in the Schist belt. \"Metarhyolite","One conodont of Devonian age","U-Pb zircon ages from metarhyolite layers 378-386 Ma, bimodal igneous zircon population about 378 and 405 Ma from Arctic deposit.","SP004",2004,"Survey Pass","Metamorphic",7260,null,null,null]
["DpCsm","Schist and marble, undivided, Arrigetch-Igikpak thermal high","Devonian to Proterozoic?","Gray marble, orange dolomitic marble, magnetite-bearing chlorite schist, and pelitic schist exposed in the central Survey Pass quadrangle.  Adjacent to the Arrigetch pluton, the unit contains calc-silicate skarn.  Mineral assemblages from most of the uni",null,null,"SP004",2048,"Survey Pass","Metamorphic",7360,null,null,null]
["DpCgn","Schist and paragneiss","Devonian to Proterozoic?","Pelitic schist, metaquartzite, mafic schist and other lithologies;  gneissic textures are more common where the unit is adjacent to metaplutonic rocks.  Mafic rocks within the unit contain assemblages stable in the albite-epidote-amphibolite facies; expo",null,null,"SP004",2045,"Survey Pass","Metamorphic",7361,null,null,null]
["OpCc_541","Older carbonate rocks of the Central belt, restricted","Middle Ordovician to Proterozoic?","Dolostone, metalimestone, marble and subordinate quartzose metasedimentary rocks, carbonate conglomerate, and metabasite.  Only exposures that contain the Ordovician part of unit OPc are included in this unit.","Conodonts, stromatolites, protoconodonts, chancellorid sclerites, hyolithids, and steinkerns of monoplacophoran mollusks, acrotretid brachiopods,agnostid arthropods, graptolites",null,"SP004",2042,"Survey Pass","Metamorphic",7741,null,null,null]
["Dsq","Quartz-mica schist","Devonian","Gray, dark gray, or brownish-gray weathering, dominantly pelitic or semipelitic schist that constitutes a major unit along the length of the Schist belt.  Outcrops vary from blocky and resistant (quartz-rich varieties) to platy and less resistant (mica-r",null,"Youngest detrital zircon population at one locality 370-360 Ma","SP004",2000,"Survey Pass","Metamorphic",8602,null,null,null]
["PzZqs","Quartz-rich metasedimentary rocks","Paleozoic to Proterozoic?","Relatively homogeneous assemblage dominated by light greenish-gray fine-grained quartz-rich schist, typically accompanied by minor layers of metaconglomerate, marble, and calcareous schist.  Exposed in the southern Central belt in the western Survey Pass","Conodont",null,"SP004",2021,"Survey Pass","Metamorphic",8603,null,null,null]
["PzZb","Metasedimentary rocks of Bluecloud Mountain","Paleozoic to Proterozoic?","Light, medium, and dark gray phyllite, dark gray to black metaquartzite, dark gray and grayish-brown calcareous phyllite, and reddish-brown weathering impure marble exposed in fault-bounded lenses along the Schist belt-Central belt contact in the Wiseman",null,null,"SP004",2002,"Survey Pass","Metamorphic",8604,null,null,null]
["DpCsc","Calcareous schist, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"SP004",2001,"Survey Pass","Metamorphic",8605,null,null,null]
["DpCsc_101","Calcareous schist - metachert and conglomerate subunit, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"SP004",2041,"Survey Pass","Metamorphic",8608,null,null,null]
["PzZem","Metamorphic rocks of the Ernie Lake area","Paleozoic to Proterozoic","Coarse crystalline marble, orange dolomitic marble, quartz-mica schist, metaquartzite, calcareous schist, graphitic metaquartzite, and metabasite exposed in eastern Survey Pass and western Wiseman quadrangles. Locally gneissic. This unit is part of the C",null,"Protolith intruded by 971 Ma granitic rock","SP004",2012,"Survey Pass","Metamorphic",8611,null,null,null]
["PzZcm","Metasedimentary and metavolcanic rocks, undivided","Paleozoic and Proterozoic?","Heterogeneous assemblage of interlayered calcareous, mafic, and siliceous rocks exposed in the central Baird Mountains, Ambler River, and Wiseman quadrangles.  This unit is part of the Central belt.","Conodonts",null,"SP004",2046,"Survey Pass","Metamorphic",8655,null,null,null]
["PzZm","Mafic schist","Proterozoic? to Paleozoic?","Dark green weathering foliated mafic schist exposed in one area on the boundary between the Ambler River and Survey Pass quadrangles. This unit is part of the Central belt.",null,null,"SP004",2047,"Survey Pass","Metamorphic",8661,null,null,null]
["pCg","Granitic orthogneiss","Paleozoic","Metagranitic rocks of several Proterozoic ages exposed in southern Baird Mountains and western Wiseman quadrangles.",null,"U-Pb zircon ages: southern Baird Mtns quad - 705+/-35 Ma; Ernie Lake pluton  - 971+/-5 Ma; Mt. Angayukaqsraq - 750 +/- 6 Ma","SP004",2011,"Survey Pass","Metamorphic",9060,null,null,null]
["Qs","Surficial sedimentary deposits, undivided","Quaternary","Frost-rived rubble on slopes and broad low ridges; glacially deposted sand, gravel, and boulders; fluvial gravel and sand; terrace deposits.",null,null,"WI007",2040,"Wiseman","Sedimentary",100,null,null,1000]
["Ks","Conglomerate, sandstone, and shale","Cretaceous","Conglomerate and finer grained sedimentary rocks that grade from massive, poorly stratified rocks rich in mafic intrusive and extrusive clasts at the base of the unit to a well-sorted sedimentary rock rich in quartz and metagraywacke clasts at the top of","Sparse plant fossils of Early to Late Cretaceous age; Early Cretaceous? marine mollusks",null,"WI007",2038,"Wiseman","Sedimentary",1990,null,null,null]
["Kvg","Volcanic-clast graywacke and mudstone","Cretaceous","Fine grained to conglomeratic greywacke and fine-grained laminated mudstone exposed along the south-central boundary of the map. Mudstone is locally tuffaceous.  Clasts are predominantly intermediate and mafic volcanic and intrusive rocks and chert with","Marine mollusks of Late Early Cretaceous (Albian) age",null,"WI007",2091,"Wiseman","Sedimentary",2180,null,null,null]
["Kg","Granitic rocks","Cretaceous","Granite, quartz monzonite, and granodiorite of the northern Ruby terrane, exposed along the southern boundary of the Chandalar quadrangle.  Includes one large polygon south-southwest of Caro mapped by Brosge and Reiser as part of their unit MzPzg; remain",null,"K-Ar dates from south of map area are 96-112 Ma","WI007",2037,"Wiseman","Igneous",2492,null,null,null]
["Khs","Rocks of the Hammond River shear zone","Cretaceous?","Heterogeneous mix of finely laminated, mostly mylonitic lithologies derived in part from adjacent units exposed in the eastern Wiseman and western Chandalar quadrangles.  Unit is recessive, poorly exposed, and includes large (up to 0.5 km across) bodies",null,null,"WI007",2022,"Wiseman","Metamorphic",2650,null,null,null]
["JCs","Sedimentary rocks","Jurassic to Carboniferous","Sandstone, shale, argillaceous limestone, limestone, dolostone, mudstone, chert and siltstone in north-central Wiseman quadrangle.  The unit conformably overlies the Kanayut Conglomerate of the Endicott Group. Consists of Kayak Shale of the Endicott Grou","Foraminifers; cephalopods, sponge spicules, and radiolarians; burrows and grazing traces",null,"WI007",2090,"Wiseman","Sedimentary",5003,null,null,null]
["TrCs","Sedimentary rocks","Triassic to Carboniferous","Quartzite, phyllite, siltstone, conglomerate, shale, sandstone, limestone, argillaceous limestone, dolomitic limestone, and cherty dolostone.  Occurs in the Mount Doonerak area in northeastern Wiseman and northwestern Chandalar quadrangles, where it is i","Conodonts; foraminifers; crinoidal packstone; burrows and trace fossils; brachiopods Wolfcampian age",null,"WI007",2026,"Wiseman","Sedimentary",5004,null,null,null]
["JDab","Mafic metavolcanic and metaintrusive rocks, metachert, metalimestone, and amphibolite of the Angayucham terrane","Early Jurassic to Devonian","Metamorphosed pillow basalt, hyaloclastic breccia, basaltic tuff, diabase, microgabbro, radiolarian and tuffaceous chert, minor metalimestone, and rare mafic schist in an imbricate package exposed along the southern boundary of the map area. Commonly, me","Radiolarians, conodonts, megafossils, foraminifers, bryozoans, brachiopods",null,"WI007",2009,"Wiseman","Metamorphic",5133,null,null,null]
["Pzpg","Phyllite and graywacke","Paleozoic?","Dark gray to black phyllite and brown-weathering greywacke, sandstone, and mudstone exposed along the  southern boundary of the schist belt.  The unit varies in breadth along strike.  In the Wiseman and Chandalar quadrangles, two subunits are recognized:",null,null,"WI007",2007,"Wiseman","Metamorphic",5565,null,null,null]
["Pzbs","Black metasedimentary rocks","Paleozoic","Dark gray to black phyllite and calcareous phyllite with dark gray to orange-weathering marble and dolostone layers up to 50 m thick, exposed in the northeastern Survey Pass and northwestern Wiseman quadrangles.   This unit is part of the Central belt.","Brachiopods Middle Devonian or Frasnian (early Late Devonian)",null,"WI007",2085,"Wiseman","Metamorphic",6331,null,null,null]
["Mc","Quartz-rich conglomerate","Mississippian?","Quartz- , chert-, quartzite-, and slate-clast conglomerate with minor thin layers of metasandstone and phyllite exposed in the Ambler River, Survey Pass, and Wiseman quadrangles.  Quartz and chert clasts are most common; chert clasts are varicolored.  Th",null,null,"WI007",2077,"Wiseman","Metamorphic",6360,null,null,null]
["Mu","Metasedimentary rocks, undivided","Mississippian","Quartz conglomerate, quartzite, metasandstone, phyllite, shale, and metalimestone in the Ambler River, Survey Pass, and Wiseman quadrangles.","Crinoids, brachiopods, corals, foraminifers, gastropods, molluscan and echinoderm debris, possible bryozoan, pelecypod, brachiopod, ostracode fragments, foraminifers",null,"WI007",2062,"Wiseman","Metamorphic",6365,null,null,null]
["SCvs","Volcanic and sedimentary rocks","Silurian to Cambrian","Volcanic rocks, volcaniclastic rocks, and clastic sedimentary rocks exposed in the core of the Doonerak antiform, northeast Wiseman quadrangle.  The unit can be divided into at least two lithologic sequences, one dominated by volcanic rocks, the other by","Microfossils, brachiopods, trilobites, graptolites, conodonts","K-Ar and Ar-Ar ages of dikes 373-388 Ma and 478 Ma","WI007",2057,"Wiseman","Sedimentary",6720,null,null,null]
["Pzj","Metasedimentary rocks of Jesse Mountain","Paleozoic","Generally fine grained, phyllitic to schistose, gray-weathering meta-argillite, black-weathering metaquartzite, marble, and brown weathering impure marble, exposed in a single area in the eastern Wiseman quadrangle.   This unit is part of the Central bel","Conodonts; brachiopods; coral fragments",null,"WI007",2032,"Wiseman","Metamorphic",6850,null,null,null]
["MDk_101","Kanuyut Conglomerate and Noatak Sandstone","Lower Mississippian? and Upper Devonian","Quartzite, pebbly quartzite, conglomerate, and minor siltstone. This unit includes exposures where Kanayut has not been differentiated from Noatak Sandstone.","Echinoderm debris, brachiopods, mollusks, cephalopods, and plant fragments",null,"WI007",2089,"Wiseman","Metamorphic",6914,null,null,null]
["Dhf","Hunt Fork Shale","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"WI007",2018,"Wiseman","Metamorphic",6925,null,null,null]
["Pzw","Metasedimentary rocks","Paleozoic","Weakly metamorphosed metasandstone, meta-argillite, phyllite, conglomerate, and rare marble exposed in two belts on the Wiseman/Chandalar quadangle boundary.  This subunit, the northern belt, is composed of metasandstone and argillite, and contains abund",null,"Detrital white mica -Ordovician 40Ar/39Ar cooling age","WI007",2055,"Wiseman","Metamorphic",6927,null,null,null]
["Pzw_572","Metasedimentary rocks","Paleozoic","Weakly metamorphosed metasandstone, meta-argillite, phyllite, conglomerate, and rare marble exposed in two belts on the Wiseman/Chandalar quadangle boundary.   This subunit, the southern of the two belts, is composed of phyllite, metasandstone with volca","Conodonts, bryozoans, corals",null,"WI007",2055,"Wiseman","Metamorphic",6927,null,null,null]
["Dmu","Metasedimentary and lesser metaigneous rocks","Middle and Late Devonian","Heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt. Includes significant expanses of rocks mapped as Beaucoup Formation by some workers. T","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","WI007",2017,"Wiseman","Metamorphic",6927,null,null,null]
["Dmu_542","Metasedimentary and lesser metaigneous rocks, calcareous, iron-rich components","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt.  This part of the unit contains a light brown, gray, and orange-weathering fer","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from subunit that contains felsic to intermediate volcanic rocks","WI007",2052,"Wiseman","Metamorphic",6972,null,null,null]
["Dmu_541","Metasedimentary and lesser metaigneous rocks, volcanic-rock bearing subunit","Middle and Late Devonian","Part of heterogeneous expanses of calcareous, siliceous, and volcaniclastic metasedimentary rocks, with lesser metaigneous rocks, exposed along the length of the Central belt, thought to be correlative with the Beaucoup Formation.   This subunit  contain","Megafossils and conodonts are Middle and early Late Devonian","U-Pb zircon crystallization age of 393+/-2 Ma from a foliated felsic rock","WI007",2043,"Wiseman","Metamorphic",6973,null,null,null]
["Pzm","Marble","Paleozoic","White to gray (less commonly black), fine to coarsely crystalline, massive to platy marble and subordinate metalimestone and dolostone occurs discontinuously in all quadrangles within the map area.  This unit is part of the Central belt.","Conodonts, silicified two-hole crinoid columnals of late Early-early Middle Devonian  (late Emsian-Eifelian) age; brachiopods; possible stromatoporoids; pelmatozoan; trilobites",null,"WI007",2023,"Wiseman","Metamorphic",6983,null,null,null]
["Dhf_101","Hunt Fork Shale - foliated exposures","Late Devonian","Dark gray to black phyllite and lesser gray-green phyllite with thin layers of siliceous or calcareous metasiltstone, lithic wacke, metasandstone, and minor layers of fossiliferous metalimestone exposed along the length of the northern boundary of the ma","Brachiopods (late Frasnian to early Fammenian), mollusks, echinoderms; Middle to Late Devonian conodonts;",null,"WI007",2044,"Wiseman","Metamorphic",7225,null,null,null]
["Dg","Granitic orthogneiss","Devonian","Tan to gray weathering, equigranular to porphyroblastic, fine to coarse grained metagranitic bodies ranging in size from less than a kilometer to over 20 kms across, found in both the Schist and Central belts.  Generally granitic in composition and made",null,"U-Pb zircon dates for orthogneiss 390-396 Ma; 375-395 Ma for orthogneiss at Mt. Igikpak","WI007",2003,"Wiseman","Metamorphic",7250,null,null,null]
["Da","Amber sequence","Devonian","Interlayered white to medium gray weathering metarhyolite, dark green weathering metabasite, pale gray weathering marble, and brown to dark gray weathering calcareous, pelitic and carbonaceous schist exposed in two areas in the Schist belt. \"Metarhyolite","One conodont of Devonian age","U-Pb zircon ages from metarhyolite layers 378-386 Ma, bimodal igneous zircon population about 378 and 405 Ma from Arctic deposit.","WI007",2004,"Wiseman","Metamorphic",7260,null,null,null]
["OpCc_541","Older carbonate rocks of the Central belt, restricted","Middle Ordovician to Proterozoic?","Dolostone, metalimestone, marble and subordinate quartzose metasedimentary rocks, carbonate conglomerate, and metabasite.  Only exposures that contain the Ordovician part of unit OPc are included in this unit.","Conodonts, stromatolites, protoconodonts, chancellorid sclerites, hyolithids, and steinkerns of monoplacophoran mollusks, acrotretid brachiopods,agnostid arthropods, graptolites",null,"WI007",2042,"Wiseman","Metamorphic",7741,null,null,null]
["Dsq","Quartz-mica schist","Devonian","Gray, dark gray, or brownish-gray weathering, dominantly pelitic or semipelitic schist that constitutes a major unit along the length of the Schist belt.  Outcrops vary from blocky and resistant (quartz-rich varieties) to platy and less resistant (mica-r",null,"Youngest detrital zircon population at one locality 370-360 Ma","WI007",2000,"Wiseman","Metamorphic",8602,null,null,null]
["PzZqs","Quartz-rich metasedimentary rocks","Paleozoic to Proterozoic?","Relatively homogeneous assemblage dominated by light greenish-gray fine-grained quartz-rich schist, typically accompanied by minor layers of metaconglomerate, marble, and calcareous schist.  Exposed in the southern Central belt in the western Survey Pass","Conodont",null,"WI007",2021,"Wiseman","Metamorphic",8603,null,null,null]
["PzZb","Metasedimentary rocks of Bluecloud Mountain","Paleozoic to Proterozoic?","Light, medium, and dark gray phyllite, dark gray to black metaquartzite, dark gray and grayish-brown calcareous phyllite, and reddish-brown weathering impure marble exposed in fault-bounded lenses along the Schist belt-Central belt contact in the Wiseman",null,null,"WI007",2002,"Wiseman","Metamorphic",8604,null,null,null]
["DpCsc","Calcareous schist, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"WI007",2001,"Wiseman","Metamorphic",8605,null,null,null]
["DpCsc_101","Calcareous schist - metachert and conglomerate subunit, Schist belt","Devonian to Proterozoic","Light gray, brown and locally orange-weathering, lithologically heterogeneous mix of marble and carbonate-rich, quartz-rich, and mafic schist derived from metasedimentary and metaigneous protoliths, one of two major units that extends along the length of","Ghosts of radiolarians, sponge spicules, bivalves, fine graphite laminae, stromatolites, conodonts",null,"WI007",2041,"Wiseman","Metamorphic",8608,null,null,null]
["PzZem","Metamorphic rocks of the Ernie Lake area","Paleozoic to Proterozoic","Coarse crystalline marble, orange dolomitic marble, quartz-mica schist, metaquartzite, calcareous schist, graphitic metaquartzite, and metabasite exposed in eastern Survey Pass and western Wiseman quadrangles. Locally gneissic. This unit is part of the C",null,"Protolith intruded by 971 Ma granitic rock","WI007",2012,"Wiseman","Metamorphic",8611,null,null,null]
["PzZcm","Metasedimentary and metavolcanic rocks, undivided","Paleozoic and Proterozoic?","Heterogeneous assemblage of interlayered calcareous, mafic, and siliceous rocks exposed in the central Baird Mountains, Ambler River, and Wiseman quadrangles.  This unit is part of the Central belt.","Conodonts",null,"WI007",2046,"Wiseman","Metamorphic",8655,null,null,null]
["DpCm","Metamorphic rocks, Mosquito terrane","Devonian to Proterozoic?","Pelitic schist, metabasite, minor felsic orthogneiss and meta-ultramafic rock exposed in two small areas along the Kobuk fault zone in the northeast Bettles and southwest Chandalar quadrangles.  The rocks exhibit amphibolite-facies metamorphic assemblage",null,"54.8 +/- 1.3 Ma white mica cooling age","WI007",2008,"Wiseman","Metamorphic",8852,null,null,null]
["pCg","Granitic orthogneiss","Paleozoic","Metagranitic rocks of several Proterozoic ages exposed in southern Baird Mountains and western Wiseman quadrangles.",null,"U-Pb zircon ages: southern Baird Mtns quad - 705+/-35 Ma; Ernie Lake pluton  - 971+/-5 Ma; Mt. Angayukaqsraq - 750 +/- 6 Ma","WI007",2011,"Wiseman","Metamorphic",9060,null,null,null]