64°W 63°W 62°W 61°W 60° 59° 58° 57°W 56°W MAP A: GEOLOGY OF THE REGION AROUND BOTANY BAY 63°S 58°W 57°30'W 63°S D'URVILLE 2b ISLAND 63°30'S Bransfield 2b 10Gd 3 72 Island 63°30'S 1:625 000 Scale A 50 N Cape A 2c T 3 10G-Gd Dubouzet JOINVILLE ISLAND 2 A a 5 71 Astrolabe G 2b Cain Nunatak R 80 13 Island Cape Legoupil 2b Geological Map of Eastern Graham Land, 2 C Broad Valley b 80 T 60 70 4b 65 I 50 C 10 7 2a 80 10 Gd Antarctic Peninsula View Point 2 Qd 2a 76 70 2b Hope Bay 2 35 a 75 3 7 S 70 4b Eyrie Bay 62 75 70 O BAS GEOMAP 2 Series, Sheet 1, Edition 1 5D U 2a 63°30'S 80 35 N 72 5G 9 80 D Dundee Island Cape Roquemaurel 2a 71 Geological interpretation and map compilation by T.R. Riley, M.J. Flowerdew, and C.E. Haselwimmer. Geological cross sections compiled by 84 Tower 50 70 13 View Point 63°30'S 4b Island T.R. Riley and C.E. Haselwimmer. Data preparation, digital cartography, design, and layout by C.E. Haselwimmer. Geological mapping and 65 80 2a 70 85 4 25 Eyrie Bay Tabarin 63°30' digital map production was undertaken as part of the BAS Environmental Change and Evolution (ECE) programme. 4 b 5G 75 b 2 Peninsula 2a a 84 13 2a 65 13 Base map data for coastlines, rock outcrops, and ice shelves from the Antarctic Digital Database. The Antarctic Digital Database is copyright Bald Head 13 Bone 20 75 © 1993-2006 Scientific Committee on Antarctic Research. 4 13 73 13 b Bay 75 Anderson 13 58 10 13 Preferred reference for map: 70 Eagle 2 Island 3 65 Botany Bay Eagle Island RILEY, T.R., FLOWERDEW, M.J. and HASELWIMMER, C.E. 2011. Geological Map of Eastern Graham Land, Antarctic Peninsula (1:625 000 Island 68 10 13 scale). BAS GEOMAP 2 Series, sheet 1, British Antarctic Survey, Cambridge, UK. 4b 13 MAP A 85 Projection: WGS 1984 Antarctic Polar Stereographic, Central Meridian: 60°W, Spheroid: WGS84. Latitude of true scale: 71°S. 4b Botany Bay EREBUS AND Egg Island Charcot Bay 75 L Trinity 80 E Published by BRITISH ANTARCTIC SURVEY, High Cross, Madingley Road, Cambridge, CB3 0ET, United Kingdom. This geological map is Island 72 Long Island N Brandy Bay copyright © British Antarctic Survey, Natural Environment Research Council, 2011. All rights reserved. 75 5 N 5 Cape Kater To A 9 13 TERROR Whisky Bay 4b H Vega Island 13 C 20 11 Scale: 1:200 000 5 13 QD 11 kilometres 5G-Gd 13 GULF 42 GEOLOGICAL LEGEND 0 5 10 40 11 13 63°45'S 4b Geological units are coloured as dark and light tints representing exposed (nunataks) or 0 5 miles 13 13 70 11 inferred geology (under ice or snow) 63°45'S V Croft Bay 13 64°S 80 68 A 58°W 57°30'W 2 9 T PERIOD EPOCH/AGE VOLCANIC AND SEDIMENTARY ROCKS PLUTONIC AND METAMORPHIC ROCKS 11 Cape Herschel 20 S 64°S 25 13 75 U 9 11 64° James Ross Island Volcanic Group NEOGENE Miocene - Recent basic volcanic lavas, tuffs, hyaloclastite breccias. Exposed widely in G 80 northeast Graham Land, particularly James Ross Island and Tabarin Peninsula area. 13 10 10 41 G 0 G JAMES ROSS 64°W 63°W 62°W 48 13 Cockburn Seymour Island Group 66 9 ISLAND Island 12 PALEOGENE Paleocene Richly fossiliferous, shallow water Palaeocene - Eocene fine grained volcaniclastic Röhss Bay 11 sedimentary rocks restricted to Seymour Island and Cockburn Island. 13 12 y 10 a G 63 11 12 B 5G 5 E s 2 G 5 4 Marambio Group e h Fossiliferous, shallow water Upper Cretaceous - Lower Palaeocene (including the g C 11 Cretaceous Plutonism u 24 8 Seymour K-T boundary) fine grained volcaniclastic sedimentary rocks exposed widely on Typically granodiorite - gabbro hybrid H 3 Late 70 N 10 11 Island 11 Seymour, James Ross and Vega islands. plutons which outcrop widely BRABANT 2 12 Cape Murray I 13 Gustav Group Emplacement age of 85 - 105 Ma. ISLAND Associated with dolerite dyke intrusion. 4 2 R Mid Cretaceous coarse grained volcaniclastic rocks up to 2.5km thickness exposed 14 Larsen b 3 5G extensively on western James Ross Island, with minor outcrops at Cape Longing and 4b CRETACEOUS G, granite; Gd, granodiorite; D, diorite; Ga, Inlet 3 P 11 84 2 9 Robertson Island. Deeper water environment with sporadic macrofossils. 10 gabbro 64 20 4 20 12 2 Pedersen Formation S b 7 11 Early o 13 78 7 Early Aptian age, conglomerate dominated submarine fan deposits and sandstone apron deposits. 61 b 81 r 3 Post-depositional deformation. Only exposed on Pedersen Nunatak (140 m thickness) and Sobral a l Snow Hill 8 Peninsula (up to 1 km thickness). Possible equivalent to Lagrelius Point Formation of lower Gustav Group. 50 C 41 P 9 h Island e 58 A a 1 n 8 r 74 i l 39 2 n Nordenskjöld Formation o Cape Longing 64°30'S t 67 s Radiolarian-rich mudstones and interbedded tuffs of Kimmeridgian - Berriasian age. t u T e 42 l 64°30'S 66 a Exposed at scattered locations along the eastern margin (e.g. Sobral Peninsula and B MAP B S a 65 7 Joinville Island) of Graham Land reaching a maximum thickness of 800m. y A Late Jurassic Plutonism Wilhelmina Bay Cape Framnes Beds 51 O Widespread acid plutons of dominantly 60 10 Cape Worlsey Coarse grained sandstones containing a Kimmeridgian - early Tithonian molluscan granite-tonalite-quartz monzonite ANVERS ISLAND Gd Rongé C macrofauna. Only exposed at Cape Framnes on Jason Peninsula. Probable basal composition. Probable sub-volcanic 2 6 Island strata of the Larsen Basin. equivalents of the Early - Middle Jurassic 65 silicic volcanic rocks (4b). Associated with Mapple Formation and Kenney Glacier Formation felsic dyke/sheet intrusion. 10 D Ga-Gd Subaerial rhyolitic ignimbrites, crystal-, lithic-, vitric-, lapilli-tuffs and rare pitchstone lava G, granite; Gd, granodiorite; QM, quartz L JURASSIC 4b flows. At least 1km thick, exposed extensively along the east coast. Dated in the interval monzonite; To, tonalite; Ga, gabbro Andvord Bay 10Ga-Gd Ö 4b 167 - 171 Ma. Interbedded with Botany Bay Group (3) at the base of the succession. Middle J Standring Inlet Basalts Wiencke Basaltic and basaltic-andesite lava flows. They predate and are coeval with silicic Island K Land Graham volcanic rocks of the region (4b). Only exposed on Jason Peninsula at Standring Inlet Group Volcanic 10G 4 58°W 57° 56° 55°W b 4a and Stratton Inlet. 5QM S 13 55 Pedersen 5 2 Nunatak N Botany Bay Group 10 8 Terrestrial, plant-bearing sedimentary rocks exposed at several locations along the east coast. Four G 4b E Early formations (Mount Flora Fm, Camp Hill Fm, Tower Peak Fm, Mt Mayhew Fm) have been identified. The 10D 3 upper part of the succession is coeval with the Graham Land Volcanic Group (4). D S 65°S 3 e 3 a 13 R l Triassic plutonism and 5Ga F l a N migmatites n d 5G Cape Fairweather O u r e 4b 13 n Legoupil Formation Extensive plutonism and s a 65° B migmatisation in southern a t 13 Trinity Peninsula Group y N a 2c Graham Land and northern 5 5Ga k MAP B: GEOLOGY OF THE REGION AROUND THE SOBRAL AND LONGING PENINSULAS65°S Variably deformed siliclastic turbidite succession with G s TRIASSIC / Palmer Land at 227 Ma and 233 rare interbedded basic volcanic rocks. Exposed 1c 2 2 13 PERMIAN extensively across northern and eastern Graham Land. - 236 Ma. This event may have 3 60°W 59°30'W 59°W 13 Robertson Hope Bay Formation The View Point Formation (2a) is at least Carboniferous continued until ~215 Ma. 15 Island 2b in age, with the Hope Bay and Legoupil formations Permian metamorphism 25 Permian - Triassic in age; confirmed by Triassic 4 4 Two generations of Permian b b bivalves at Cape Legoupil. metamorphism are recorded as 9 64°15'S View Point Formation zircon overgrowths and granitic 3 1b migmatisation. The two phases 64°15'S 2 2a 2 10G 5Gd are at 275 and 257 Ma. 63 5G CARBONIFEROUS/ 4b Ordovician - Carboniferous DEVONIAN/ crystalline basement 75 ORDOVICIAN 4 2 b 60 Early Ordovician (484 - 487 Ma) T 5QM diorite gneisses on the Eden Glacier, Exasperation 80 4b Devonian (393 - 397 Ma) orthogneiss and Carboniferous (327 11 24 5QM Inlet 35 1a ± 9 Ma) at Target Hill. S Mount Tucker 70 3 Mapple Glacier 2 3 Tower Peak GEOLOGICAL SYMBOLS 3 12 65°30' 12 B 15 e a A s c Fault Bedding Fault breccia o c 15 Cape 70 h e 4 30 4b Mount Elliott a b 14 B a 4 Disappointment 4 y 3 b b 65°30' 4 b L Strike-slip fault Overturned bedding Mafic dykes 3 42 O Larsen o 65°30'S Mostly fine grained feldspar-phyric dolerite dykes. n Typically <1m thickness and steeply dipping. 2 20 LongingGap 3 5 5 g Normal fault (tick on Probable age range, 95 – 110 Ma. QM QM Contorted bedding i downthrow side) 10 Inlet n 20 12 2 Felsic dykes g C 4b Porphyritic quartz-feldspar felsic dykes and sheets. 7 7 P Fold axis of synform 55 Cleavage or metamorphic foliation Up to 80m in thickness and shallowly dipping.