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UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY I Geologic Map of the Teller Quadrangle, Western Seward Peninsula, Alarska By C. L. Sainsbury Open-file report 19 70 This report is preliminary and has not been edited or reviewed far conformity with Geological Survey standards or nomenclature, GlmmKC HAP OF TRE PBLUR QUADRANGLE, Page WBmSEWAIlD PEHlHSaA, ALASKA Iatduction------------------------------- 1 &ologg------------------------------------ 1, &era1 stratigraphy----------------------- L P rec-flen roeb------------------------ 3 IITWIOII The Teller quadrangle the of Kigluaik Group------------------------ 3 kncluder u%sternmmt tip the lorth to of wdlmer pare-------- ----- ---- 3 American Contsm~aentat its d-at approach Siberia. Ruck snd Paleozoic an: intricately aa Tigaraha Schfat------------------- 4 Preenmbrian age interdxad the result in Co1Lier Orth~g~~~-------- ---- -------- 4 of tntenae overthrust faulting the thrust belt [Saimbury, Age---- .......................... 4 196%). ~& of the early work on the Sward Peninaulr was by rapid now Group-------------------------- 5 recannaisaance 8nd is now outdated: therefore the geologic data and Upper Pr*drian rocks-------------------- 5 here baaed upon work mince Age of the upper Precambrian mcka---------- 6 concluaim~presented are principally my Paleomte rocks---------------------------------- a 1958. Except for Smfzb's (1910) work around Worne, the tbwt relatiow were unrecognized mapping; racks---------------------------- 8 during the early raeonnaissmce hence, sock= widely agsu grouped. retaina Cretaceous and Tertiary(?) rocks---------------- 8 of dlf ferent were The preseot report Tertiary or Quaternary rocka----------------- 9 previous groupings where feasible; where not, older n-8 ara abandoned or wdified Pletstossne roe&------------------------ 9 . Pleistocene and Holocene upconsolidated depsita----- 9 mmm 9 Gwaral stratigraphy Ore deposit~-----------.--------------------------- 10 Early workare who mapped par- of the area copsred by thT8 tep6tt Patroleum potential----------------------------- 12 dfstinguirhed md amed several lithologic units. Bmb(in Brooke Reference= cited--------------------------------- U and others, 1901) applled the name tiglualk Serier to the lbesrtwes, achiatu. and granites of the KlgLuaik 14Duntain8, and the nme Kuzitrin Series to pephitie mchisrs and related xockm on the north and south midem of the rormtaha. Ae belted theam rock8 to be of Psleozoie age or alder. iroob rho d the liae Seties, and mtated that it mehted af "lirestmee, graphitic dea and calcareous schlsts with rsnp grteostaae intrusive8 and sow! chhrktic schisba." Re ccmaidered it to be of Hesnzoic md Pdeoroic age: Collier (1902, p. 15) subdivided the 8- Sesies into the Port Clarence Lkstme, of rocks now ansigned to the "elate of the York regloa," a tern first Silurian age, and the Kugryk Gmnp, wtdch consisted of "lnterrtratified used by Knopf (1908, p. 13). limestones, mica scltist~,and graphitic ~ehiat~.~'Hoffit (19131, who "Slate of the York region" .-Tbia infarral mm~is retahd for mapped in the Homz area and in the IEigluatk nDlmtrdns in 1904-5. and ~rapbitic, slaty. or phylritic mdrs of late PrecardBrlm age, rrhich who f-d the agparrnt scratlgraphy LW owph that he defed come originally aswaisted rainly af silt-sired quartz grafua in a latian6 , divided the Kiglualk Group into the Tigaraha Schist and vari- carbonaceous matrix, and hich are widespread over the Sward our intrusive types, and the older crystalline limestunes and gaeiaesr. Fenbsula. Locally, these rock^ id& thin black lirestone. Fbffit (1913, p. 27) also changed the radc of the Hare Series to Plw calcareous graywacke, and, %a the dclrdg of granite, biotite- Group, and stated that it contained principally chloritic schist and andalusire- touwalina rocks. small- gg~lmtsof feldapatbic and elliceow graphitic schist. Fort Clarence tiPestwc.-Tbfa designation is abanhed, for it ~a8 later workers (for exmmple, Sdth, 1910) retained thee DM, and expanded from the original designation to include rocks ranging in addad others to accommodate lithologic variations in restricted areas, age from late Precambrian &rough Mtssissipph. In thh report, arr tbt considersble cdtwiw resulted. 48 pointed wt prepiwsly each Ifmestone amit is ref&& only m the sgsten represen-. (Salnabury, 1965, 1969~), this cwf uaim was caused becauee rocks of Precambrian rocks diverse age and lithologg acre juxtaposed or seedagly interstratified Groug by uidespread thrust faulting that affected the entire Sewad Pminsala Unnamed lower part.--The unnamed lower part of the Kiglueik Group, in the Cretaceous. which ha expoad at the weat base of Phmf'Qmbornjust off the south In the present report, established tsrnfnology is retained where border of the quadraagle, cwtrists of banded quartz-pla@oelaa+ possible, bur, except for the Kigluaik Gtmp, demignafed units are biotite-garnet-paragndno (pegnl), originally calcareow, cut by nlrmer- con~iderablyrestricted. Present urage ir as Follows : ow pis, I--, addikss of madtic gneiss. The ariginal carbonate Kiglaaik Group.-The Klgluaik Group iaclltdea mcks of Pmrianage in am calc-sllicata rock, pith locd bits of coarse-grained calcite. only, comprising all of Maffir' B (1913) units, including the Tigaraha The granitic gneiss dikes are folded mdatt~ated. The gnetssi In the Schist: it includes Precdudan orthogaei~a,but excludee Cretacww lower part of the Kigluaik unit har an exposed thicknescl of 1,500 feet igneous rocks. The Tigaxaha Schtst as here uaed includss soae on mt(IBborn; the base is not erpsed, and the gwiss ia tranaitimal marbles and cnlcareoue sequmcecl, but excludes acme graphitic. into an werlying coarse-grained marble (pw, which here icl about siliceous rocks nm referred to the "slate of the Pork region." 500 feet thick. Husdte and either olivine or montiesllita are chax- Nome Group.-This name is restricted to rocks which are of Precdrian acteri~ticof the marble. Becauee of flowaga and recrystallizatiw, age, and which consist af chladtic achiet d marble scbiat, with the dlevadw fn rbiches's, and meof the original bedding is minor arouats of graphitic, chloritfc scbisr and metammtphosed gab- preeeved. broic rocks. Ma~sivemarble and limestone of Paleozoic and latest The prarble im overlain ebruptly by eddtzional b& gneiss Precambrian age are excluded. ~pSpuJ,which ca1t4.w desilicate mebs d biorlbe s&lst. the Kuzitrin 5etiss.-This mame is abandoned, for it lncluded rockr correl- main difference between the upper end lower aneiemes is that the upper ative with part of the Tigaraha Schist, al well as younger graphitic gneisa ermtaina a larmr awnmt of crrlc-silicate rock and blotitegarnez schist. 3 Tigaraha Schist.-+ithin the area of tae Teller qudrmgle, tbe rocks of this type frm ather areas, I interpret this age as being the Tigaraha Schimt (pa) is eompoasd principally of graphitic biotite time of matemorphism. X believe a Precddan Qe for these rodre i~ chi st, calcaredua biotite schist, end biotite-garnet schist, and it mrrongly suggested but not conclusively proved at thfs time*" abo cmitains several calcar;eolls sequences. 8mraua varfatioas were OD tbe Bamia of these apdates and the abdaat -Logic evidence noted on the south side of the Eigluaik Hwntains, where stamolite that the rocks are much older than the "slate of the York regfm," schist, siliceous graphitic schirt, end calc-silicate rocb occur. which is iteelf older than unfossiliferow rocb below the Lower Or&- MoEfit (1913, p. 21) included graphitic sfliceaus schist that ia wide- deim li*estmes of the York bunteins {Sdosburg. l%5. 1969c>, I spread w the south side of the KtgluaiL lhmtaim with the Tigaraha curtalder the Precmbrian age ast&liehed. Schist, whereas narlier workers considered thin graphitic e&i~tto be #me Group part of the Kunitrin Series (in the present report, these ailiceow, The lome Group (ph), originally named md dacribed by Brooks, graphitic mdrs are referred to the "slate of the Yark regiodr). Bidmrdson, and Collier (1901). but reatnlctd bare to rocka of Within the Tigaraha Schist are eeveral calcareow sequences of Preca&rian age, mists of graenisb schist with mrwa intarcalated considerable thickness. One sequence i~ compicuoua along the north layers of marble and marble schiet, all of which ate intruded by numer front of the Kigluaik Mountains, and was mapped separately as a calcar- om dikes and plugs of altered mfic racks. For the -st part, the eoum eubrmit IpQbm) of the Tigaraha Schlst. A sectLoa measured in the schist (pgcl) fs of magnesian chlorkte, epidote, albfte. headwaters of a small mudet- flowiw iato Windy Cove of Imruk quartz, calcitm, amphibole, and apbeue; locally, garnet and glaucophane Basin from just east of the small body of fine-grained granite cw~imf8 occur, particularly in the east part of the quadrangle. The marble of a lower unit 80 feet thick of marble containing rolled quartz schist (pslaj displays ab&t drag folds overturned to emst or mrth; "rods," a middle uuit 360 feet thick of qwrtrbiotite schist with those overtmnd ea&t mmudly have hodmtd a*as rritlr an intense calcareou~leasmi, pods, and thia bear, and an upper unit 550 feet -at-plane lineation that consiste of cltriatim and almgated new miner- thick of marble. ala. Allnost avarywhere a second plane of foliation cmsscuta the Orthomebe.--The Kigluaik Gmup rock6 are intruded by ummmw earlier mhistoaity. clwrly rewrdiag two o~ta~rphiccycles. All the igneous rocks incltlding a quartrbhtite o~hogneiss(pbgn) vith latble schist layarm cootala a-
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