Lexicon of Antarctic Stratigraphic Names: Introduced by Members of United States Expeditions (1972)

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2 . Definit ion "A s light increase in plateau level and hence re-es tablishment of the ice supply over the threshold caused the Upper Wright and Webb Glaciers to re juvenate and recommence downcutting . " (Bull et al , 7 5 ) 3 . Type section a. Location Wes tern end of North and South Forks , Wright Valley , Victoria Land b • . Lithology MOraines , coarse and angular , lack ventifacts and sand dune areas . Fros t -heaving , and frozen ponds rimmed by salt encrus tat ions . Thick boulder moraines . 4 . Synonyms or closely related names See Koettlitz Glaciat ion depos its 5 . Remarks Work conducted by New Zealand Expedition Hallett Volcanics 1. Firs t published use Hami lton , W . The Hallet t Volcanic Province : Ant . Jour . U . S . 2 , P • 177 - 178 , 1966 . 2 . Definition "Four long , narrow pi les of late Cenozoic basalt and trachyte rise from the continental shelf in a broken line trending northward along the mountainous Ross Sea Coas t of northeas tern Victoria Land . From south to north , the piles are Coulman I sland ( the shortes t , 33 km) , Daniell Peninsula , Hallett Peninsula , and Adare Peninsula (the longest , 7 7 km) . 3 . Type sect ion a. Location Off Ros s Sea coas t of northeas t Victoria Land - 42 -

b . L i thology '111 i ck foundat ion of palagoni t ic brecc ias , p i l low-brec c ias , d ikes and s i l ls topped by a veneer o f subaerial flows and tuffs . U l trama f i c basanite& to extreme ly sod ic trachytes ; mos t ly alkal i aug ite , ol ivine , and p lag ioclase bas al t s . He lser S andstone 1 . Jo• t rs t pub l ished use S chmidt , D. L . , P . 1 • • Wi l l iams , W . H . Ne l son ilt}d .J . R . Egt! . I I pper Precambrian and Paleoz o i c s t rat igraphy and s t ruct ure of the Neptune Range , Antarct ica : USGS l,rof Paper 52 5 -D , p. 1 1 2 - 1 19 , 1 96 5 . 2 . De f in i t i on "The Heiser Sands tone is here named for Heiser Ridge • • • • The He iser cons is ts of a l ight -green to brown quartzose sands tone Wh ich is moderate ly we l l bedded in beds 1 to 3 feet th i ck . The s ands tone is character ized by the common occurrence of s col ithus -like tubes of lighter colored quartz ite in a darker , les s well indurated , encompas s ing s ands tone . The tubes range from 1 /4 to 1 inch in d iameter , are characteris t i cal ly perpend icular to the bedding planes , ar.d commonly extend through the thicknes s of only one bed . " ( S chmidt and others , 1 16 ) 3 . Type sect ion a . Location Wes tern end of Heiser Ridge , Neptune Range , Pens acola MOuntains , 83 ° 49 1 S , 5 7 ° 25 ' W . b . Thickness 1 , 000 feet c . Lithology Light green to brown quartzose s andstone wi th s c o l i thus - l ike tubes . d . Re lation to other un i t s Gradationally overlies Elbow Formation Conformably overlain by Dover Sandstone . - 4 3 -

�=-:o:q;er �a:: .-r:-e � �l..so!:l !..i.Jiestooe of t::::.e � . 7.:t £rem eocsf..de:rai.c:Jas it u pro:,..ly not � t"- z: Late ?aleozoie. · {S<±lrick Ed oeera , 115 ) . � t:ap �e: �.oaT � 1 . First p.;.b1i.a::.ed � Cra6dock, C. • J. J . .A:ldersoo a::d G . F . Vebers. Geologic: outline of the Elheot th Jbuntains : Antarc:t:ic Geol.osY , Proc:. Cllpetoml SJWPOS i� 19?3 , Joen •itey and Sana , p. 155-1707 1964 . 2 . Def i.niti.on "1he olde:at strua in the E 1heot th lbmtains crop out in a 1oog strip in the �h ""W'e:Stern and north cemral Heritage Kaoge. these rocb are believed to be in nor.al depos itiooal c:ontac:t with the overlying quartzite fOIWilti.on on the wut and in fault c:onUc:t with it on the eut , at least to the south of Bastien Glac:ier. F�l strU igrapb ic c lus i fi cation of these beds is not yet possible ao they are treated together here a an infOIWill group. (Craddock and others , 161) . a . Location Long strip in soutbweatern and north-central Heritage Rap , E 1 t.wortb lbmtains . b . Lithology (aac:endin.g section) 'l'hidmeas 1) c:alc:areoua c:ongla.erate , weathers ltaht gray and for.B ... s ive ridges 800 feet 2 ) thin- to .ediua-bedded silty lt.ea tooe , locally oolitic 500 feet 3) med iua- to thick-bedded , white to -.Hua g ray 1t.eatone and marble 2000 feet 4) green and dusky red phyllite and alate , aoae sandstone and cong1oaerate 7000 feet finely crystalline lava flow 100 feet boulder c:ongloaerates - 44 -

5 ) light buff quartz itic conglomerate , rounded quartz ite boulders to 10 feet 700 feet 6 ) greenish -grey phyllite interbedded with quartz ite and conglomerate lO , OOO+feet 7 ) badly sheared wh ite to light grey marble 900 feet 8 ) dark pelitic rocks with rare thin carbonate interbeds 2 , 000 feet 9 ) mass ive marble bed , some foss ils 25 - 300 feet 10 ) gray petite with interbeds of quartz ite abundant upward 200 - 500 feet c. Relation to other units Overlain conformably by Crashs ite Quartz ite d. Evidence for age Unit 9 exhibits trilob ites , mollusks , articulate and inarticulate brachiopods , echinoderm columnate . Preliminary invest igat ions of this fauna indicate a late Cambrian age . Horlick Format ion 1 . Firs t published use Long, W. E . Sedimentary rocks of the Buckeye Range , Rorlick MOuntains , Antarct ica : Science , vol . 135 , p . 319 -321 , 1962 . 2 . Definition "The bas al sedimentary unit , named the Horlick Format ion , is composed of interbedded sands tones , s ilts tones and shales which range from 0 to 150 ft . (46 m) t.n th ickness . The beds contain :f.nvertebrate foss ils and primit ive paludal plant fos s ils (ps i lophytes ) indicative of early Devonian Age and nearshore and swampy environments . The upper surface of the Horl ick Formation commonly is grooved and s triated and forms a basal glacial pavement below the Buckeye Tillite . " (Long , 3 20 ) 3 . Type section a. Location Discovery Ridge , Oh io Range , Horl ick MOuntains - 45 -

b . Thickness 0 - 150 feet c. Lithology Interbedded sandstones , s i lts tones , and shales . Sands tones are yellow gray , poorly sorted , sub -rounded to sub-angular fragments of quartz with varying amounts of clay , feldspar and metamorphic rock fragment s . Foss ils include brachiopods , bryozoans , pelecypods , cephalopods and trilob ites . d . Relat ion to other units Overlies Horlick MOuntains quartz monzonite nonconformably. Overlain by Buckeye Tillite disconformab ly . e . Evidence for age "The dark carbonaceous and somewhat s ilty shales of the Horlick Format ion contain primitive ps ilophyt ic plants and a characteris tic early Devonian spor- assemblage , according to J . M. Schopf (personal communication ) . Both animal and plant foss ils are indicative of an early Devonian age . Apparently all of the Horlick Formation in the Ohio Range was depos ited during the Ema ian stage of the early Devonian. " Long , W . E . The strat igraphy of the Horlick MOuntains : Antarctic Geology , Proc Capetown Sympos ium 1963 , John Wiley & Sons , p . 352 -363 , 1964 . Horlick MOuntains basal sands 1 . First published use Long , W . E . Geology of the Central Range , Horlick Mts . , Antarctica : IGY Antarctic Sympos ium, Buenos Aires , p . 75 , 1959 . 2 . Definit ion "The sedimentary rocks lie unconformable on the exposed bas ement rocks . Some Terebratuloids , s imilar to Rensselaeria falklandica Clark of Lower Devonian age , were found in the bas al sand . " (Long , 7 5 ) - 46 -

3 . Type section a . Locat ion Central Range , Horlick Mountaiu b . Relation to other units OverU.es bue•nt unconformab ly . Overlain by graywacke , friable s ilts tone and sedi•nts s iailar to Beac:on Sands tone . c . Evidence for age 4 . Re•rka "S� Terebratuloids , s iailar to Rensse laria falklandica Clarke of Lower Devonian age , were found in the basal sands . " (Loaa , 75) Name obsolete . See Horlick Format ion. Horlick MDuntaiu granodiorite 1 . First publ ished use Treves , s . B. Igneous and •tamorphic geo logy of the Ohio RaDge , Horlick Mountains : Polar Record Vol . XI , no . 75 , p . 776 , 1963 . 2 . Definit ion "The base•nt cqu is ts of a pink , coarse -grained , s l ight ly gneis s ic , porphyritic quartz moozonite that is intrus ive into a grey-white •diua­ to coarse -grained , gneiss ic , locally porphyritic granodiorite . The field relations indicate that the granodiorite is closely related to the quartz -monzonite and that is probably an early phase or •rginal facies of the •in intrus ive phase . " (Treves , 776 ) 3 . Type section a. Locat ion Ohio Range , Horlick Mountaiu b . Lithology Cou is ts of quartz , perthite , oligoclase , b iot ite and ra�e hornblende . - 47 -

c . Relation to other units Intruded by quart z �zonite . Horlick Mountains quartz monzonite 1 . Firs t published use Thiel , Edward . Antarct ica , One Continent or Two? : Polar aecord 10 ( 6 7 ) , p . 335-348 , 1961 . 2 . Definit ion "The outcrops vis ited in the eastern Horlick Mountains are monzonite capped by rocks inferred to be sedimentary , but· Which could not be reached in the t ime availab le . " (Thiel , 343 ) 3 . Type section a. L�cat ion E astern Horlick Mountains b . Lithology Pink , coarse -grained , s l ightly gneiss ic porphyritic quartz monzonite ; quartz , perth ite , oligoclase and biot ite . 4 . Remarks Name obsolete . These outcrops are nov known as the Th iel Mountaius . See Thiel Mountains quartz monzonite porphyry. Hudson Mountains olivine basalt 1. Firs t published use Wade , F . A . , and K . E . LaPrade . Geology of the King Peninsula , Canisteo Peninsula and Hudson Mountains area, E l l swor th Land , Antarctica : Ant . Journ . u . s. , Vol . IV , p . 92- 93 , 1 96 9 . - 48 -

2 . Definition "Rocks of the Hudson Mountains and King Peninsula cons ist of olivine basalts and tuffs . Well -developed pillow lava occurs at Mount Nickens , but elsewhere the lavas occur as thick layers of acoriaceous olivine basalts , typically inters tratified with tuffs . " (Wade et al , 93 ) 3 . Type sect ion a . Location Hudson Mountains and King Peninsula , Ellsworth L&nd b . Relat ion to other units Overlies Canis teo Peninsula gneiss Hudson MOuntains olivine-basalt pyroclas tics 1 . First published use Craddock , c . , T . w . Bast ien , R . H . Rutford . Geology of the Jones Mountains area : Antarctic Geology , Proc . Capetown Sympos ium 1963 , John Wiley and Sons , p . 171-187 , 1964 . 2 . Definition "The Hudson Mountains lie 150 km south-west of the Jones Mountains and are of s iudlar s ize . They are volcanic cones composed of olivine­ basalt pyroclas tics (personal communicat ion from T . Laudon) . They are cons idered by Laudon to be young because of their dis t inctive undis ­ sected forma . . . . There is a good pos s ibility that these volcanics are closely related to the Tertiary olivine-basalts in the Jones Mountains . " (Craddock and others , 185 ) 3 . Type section a. Locat ion Hudson Mountains , 150 km southwest of Jones Mountains . Hut Point basalt 1 . First Published Use Forbes , R. B . Ultramafic inclus ions in basaltic rocks , Hut Point Peninsula , Ross Is land , Antarctica : GSA Spec . Pap . 73 , p . 39 , 1962 . - 49 -