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500 lOOOMOTtcn ANTARCTIC PENINSULA s/2 9 !S°km " A M 9 I C j O m t o 1 Comandante Ferraz brazil 2 Henry Arctowski polano 3 Teniente Jubany Argentina 4 Artigas uruouav 5 Teniente Rodotfo Marsh emu BeHingshausen ussr Great WaD owa 6 Capstan Arturo Prat ck«.e 7 General Bernardo O'Higgins cmiu 8 Esperanza argentine 9 Vice Comodoro Marambio Argentina 10 Palmer usa 11 Faraday uk SOUTH 12 Rothera uk SHETLAND 13 Teniente Carvajal chile 14 General San Martin Argentina ISLANDS JOOkm NEW ZEALAND ANTARCTIC SOCIETY MAP COPYRIGHT Vol. 12 No. 4 Antarctic Antarctic (successor to "Antarctic News Bulletin") Vol. 12 No.4 Contents Polar New Zealand 94 Australia 101 Pakistan 102 United States 104 West Germany 111 Sub-Antarctic ANTARCTIC is published quarterly by Heard Island 116 theNew Zealand Antarctic Society Inc., 1978. General ISSN 0003-5327 Antarctic Treaty 117 Greenpeace 122 Editor: Robin Ormerod Environmental database 123 Please address all editorial inquiries, contri Seven peaks, seven months 124 butions etc to the Editor, P.O. Box 2110, Wellington, New Zealand Books Antarctica, the Ross Sea Region 126 Telephone (04) 791.226 International: +64-4-791-226 Shackleton's Lieutenant 127 Fax: (04)791.185 International: + 64-4-791-185 All administrative inquiries should go to the Secretary, P.O. Box 1223, Christchurch, NZ Inquiries regarding Back and Missing issues to P.O. Box 1223, Christchurch, N.Z. No part of this publication may be reproduced in Cover : Fumeroles on Mt. Melbourne any way, without the prior permission of the pub lishers. Photo: Dr. Paul Broddy Antarctic Vol. 12 No.4 Polar activities Winter life at Scott Base to be filmed by Television New Zealand New Zealand's 1990-91 Antarctic Research Programme finished on Wednesday February 20 with the departure of the last summer staff and field personnel from Scott Base. Over 260 scientists and support staff took part in the 44 projects undertaken since early October. Under the joint logistical arrangements ilton, telecom technician; Helen Wills, also of with the United States Antarctic Programme Hamilton, Telecom Supervisor; Jack the last flight for the season left McMurdo on Jenniskens, a mechanic from Stratford; Peter 28 February. The two winter teams have now Harding, base engineer from Wellington and started six months of isolation broken only by Phil Clerke from Blenheim, who is store telephone calls and winter resupply sched keeper and provided field support for the uled for June 25 and 26. summer. Leader for the winter at Scott Base is Ross In addition a two man crew from Televi Macdonald of Tokoroa who is also Engineer sion New Zealand are spending the winter at ing Manager. the base. They are Max Quinn (producer and Others in the party include Karen Gage, a director) from Dunedin and Don Anderson chef from Bumham, Sally White of Springfield, (soundman) from Little River. who is part of the domestic staff; Peter Kraak, Among the field programmes successfully Chris McCarrell and Max Olliver, all techni completed these season were: cians from Christchurch, Roy Joblin of Ham- *rw 84*30" Location an route of the Seris experiment 94 Vol. 12 No. 4 Antarctic Geophysics, Wellington and Dr Uri ten Brink, The SERIS experiment of the Department of Geophysics, Stanford Crustal seismic investigation across the University, California the party comprised 15 boundary between East and West Antarctica. people including two drillers, two surveyors Undertaking one of the first large-scale (for the initial flagging of the line), three field modern multichannel seismic experiments in assistants, a mechanic, camp manager, two the Antarctic interior this season was a joint seismic engineers and four geophysicists. New Zealand-United States party. Working The profile was to cross the Transantarctic from three principal camps the team com Mountain front via glaciers and the Ross pleted a profile 142km long across the Ross Iceshelf. Initially the party were to use the Ice Shelf and the Transantarctic Mountain Skelton, the only one previously traversed by front just south of the Nimrod Glacier. heavy vehicles, but the orientation and loca The purpose of the project was two-fold; tion made this impossible. Instead after exten firstly to image the geological structures formed sive inquiry and two CI30 reconnaissance at the boundary of East and West Antarctica flights in January, the interconnected glaciers and secondly to test different seismic acquisi Robb and Lowery, some 80 km north of the tion techniques which may be used in future Beardmore Glacier, and just south of the seismic exploration of the continent. Nimrod, were chosen. In addition to their With a total length of 3000-3500km and location, each glacier offered a moderate elevations up to 4500m the Transantarctic topographic slope and both were relatively Mountains are one of the major Cenozoic free of crevasses. The Robb-Lowery route ranges in the world. They are bounded on was also found to be nearly windless because their eastern margin by steep normal faulting the Markham Plateau to the west blocked the and can generally be described as gently tilted flow of katabatic winds from the Polar Pla block-faulted mountain ranges. Parallel and teau. just offshore in the Ross Sea sector is the Leaving Scott Base in the first week of Cenozoic age Terror Rift. The Ross Embay December about 12 C-130 flights were re ment as a whole is a vast submerged region of quired to put the main party into Mike and extended continental crust which has been Lima Camps. The exercise required that some dissected by several rifts probably during the 80 tons of equipment, consumables and peo Mesozoic and Cenozoic. It is commonly as ple be moved into the field including a Hag- sumed that the Transantarctic Mountains form glund, two Tucker snocats, one Sprite and five the boundary between the two major conti skiddoos. Eleven tons of dynamite were used nental plates described as East and West but this was not detonated all at once. About Antarctica. 1400 shots were fired, each using 5-7 kilos of The boundary is of particular interest as it dynamite. To ensure good radio communica is one of the few continent/continent bounda tion the expedition established their radio ries on earth where the juxtaposed plates are transmitter on Mt. Christchurch. separating rather than colliding. The result of The party carried about 23 km of seismic this process has been the development of a cable and over 100 geophones. Hot water deep basin on one side of the boundary and drilling techniques were used to make the an elevated Mountain range on the other. (approximately) 1400 17 - 20 metre deep It is anticipated that analysis of data ob holes in the ice for detonating the charges. tained by the use of modern multichannel This work was contracted to PICO (Polar (Ice crustal reflection/refraction techniques, should Coring Office, University of Alaska) through explain the nature of the faulting across the the National Science Foundation. Two thou transition, the variation in crustal thickness sand gallons of fuel were used to melt the snow across the plate and the presence or other to produce the hot water and a further 800 wise of the southward continuation of the gallons were used by the whole expedition. Terror rift. The first third of the profile took them from Led by Dr Tim Stem of DSIR Geology and just west of Mike, a depot, about half way 95 Antarctic Vol. 12 No.4 between Scott Base and the South Pole,at of at least 90 km and wide angle-reflections the junction of the Lowery and Rob Glaciers from deep within the crust. down the Robb and past the north end of the Analysis of the multichannel reflection and 3000 metre high Holland Range which rises refraction data is currently underway at the steeply at the boundary between the Ross DSIR in Wellington and at Stanford Univer Embayment and East Antarctica. The last sity. The results should show a wealth of two thirds of the profile stretched east across crustal reflection with the iceshelf portion of the Ross Ice Shelf over ice 200 to 500metre the survey and a seismically more transparent thick. This provided two "sample environ crust within the Transantarctic Mountains. ments", the first over a grounded glacial ice overlying crystalline basement and the sec ond over floating ice layer overlying both Model building and water and sediments.Seismic reflection, re fossil analysis fraction and gravity data were collected along Working in the Allan Hills area 150 km the line. north-west of Scott Base from 1 December to Two different systems were used to collect 24 January were Ken Woolfe, Dr Peter reflection data. The first was a conventional Barrett, Malcolm Arnot of Victoria Univer cable and buried geophone system and the sity. They were accompanied by Drs Jane second a towed "snow-streamer" loaned from Francis of the University of Adelaide and Norsk-Hydro in Norway. Seventeen to 18 Norm Smith from the University of Illinois. metre holes were drilled in the ice by a hose The Permian-triassic of South Victoria ejecting water at 80 deg C and at high Land contain some of the best exposed fluvial pressure. Spaced at 200 metre intervals, rocks in the world and Allan Hills is one of the three to five could be drilled in an hour. better examples. The party were seeking to Charges were placed at the bottom of each describe the strata and sedimentary struc and the results recorded on 48 groups of 14 tures they contain in order to reconstruct the Hz geophone strings with six units per string channel morphology and flood-plain charac and placed at 50 metre intervals for the first teristics of the river system.