South Shetlands & The Antarctic Peninsula 22 Feb 2020 - 14

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The Geological Structure of the Antarctic Peninsula David Macdonald, Lecturer (Geology) & Expedition Guide This cartoon shows what the Antarctic Peninsula looked like 100 million years ago (mya). The main points to note are: • The peninsula was a continuation of the Andes. They were connected until 35 mya • The peninsula was a volcanic arc from about 200 mya3 until about 25 mya • Volcanism ended 50 mya in the south and 20 mya off Brabant Island • Only the South Shetlands Islands have any volcanic activity now 15 There are three main geological domains, each formed of multiple rock units: 1. The basement domain (grey and brown colours) contains sediments scraped off the ocean floor which were changed by heat and pressure (metamorphosed) in the subduction zone and during folding and deformation. These metamorphic rocks span a wide range of ages from 299-65 mya. They tend to be older on the east coast of the peninsula. These rocks are best seen in Paradise Harbour, at the shag colony near Brown Station. 2. The igneous domain contains rocks crystallised from magma. This includes both plutonic rocks (where the magma crystallised slowly within the earth’s crust) and volcanic rocks (where the magma was erupted as lava and ash). Again, the rocks span a wide range of ages from about 210-25 mya, and the younger rocks tend to be in the west. These are the commonest rocks seen in the Peninsula and are well displayed in the South Shetland Islands (e.g. Half Moon Island, or Yankee Harbour) or on the peninsula (e.g. Cuverville Island). Plutonic rocks form Goudier Island at Port Lockroy. 3. The sedimentary domain contains rocks eroded from the volcanic arc and deposited in sedimentary basins, either on the eastern, Weddell Sea side (in a very large structure called the Larsen Basin), or in smaller basins to the west (the largest of which is the Fossil Bluff Basin on Alexander Island). Sedimentary rocks are not seen on most peninsula cruises (unless they visit the area of James Ross Island), although there are sedimentary rocks with abundant fossils interbedded with volcanic rocks west of Hannah Point, in Walker Bay. 22 FEB- 2 March 2020 Volume 2, Issue 14
Day 5 – In the Footsteps of Charcot 26 February 2020 – Peterman Island and Port Charcot 16 It was an especially early wake up call for an especially exceptional view. At 6:00 am we rose to Sam’s voice on the loudspeaker announcing our transit through the Lemaire Channel. World famous, and for good reason, this was not an event to be missed for a bit more sleep, so we bounced out of bed for a viewing on the bow. With a few high clouds to offset the orange sky and the sun rising behind the mountains, we threaded the needle through the narrow channel. A rainbow appeared, backdropped by the charcoal clouds; we couldn’t have asked for a more beautiful morning. At lunch there was a barbecue on the back deck that trumped all other barbeques! What can beat the sweet smells of summer picnics to be eaten whilst cruising amongst icebergs? @ Amanda Dalsgaard Breakfast was at the usual 7-8 am slot and we quickly got ready for the morning’s excursion at Petermann Island. As we approached the shore, we could see a cross to the left along the beach commemorating three British researchers that had perished crossing the sea ice. On the shore, the red flags led us to a fork in the path with a high viewpoint over an iceberg-filled bay to the left and to the right we met our first Adelle colony. Ab was there to tell us the differences © Sandra Petrowitz between the Adelle and Gentoo penguins. @ShayneMcguire @ShayneMcguire The afternoon excursion was a landing at Port Charcot and a cruise through Pleneau Bay- an iceberg graveyard, where “icebergs go to die”. On our walk as we crested over the sun cupped snowfield to the iceberg laden bay at the back, we came upon many penguins that had been ravaged. The mystery was, why were they killed and not eaten?. A mad fur seal was the suspect as they are the only kind of seal that could move fast enough to impose such damage on a colony. It was a sad sight and a disturbing part of nature to witness. The zodiac cruise amongst the icebergs in Pleneau Bay was an antithetical contrast with a magical meander amongst the crystalline shapes melting out from the large blocks that not long ago were stranded on the shallow ocean floor. At 18:00 we had another chance to cross the Lemaire Channel and this time in the evening light. We had a group picture taken on the bow of the ship by Shayne; it will be great to remember all our new friends that we met on this journey. The evening ended with Rose’s entertaining banter over a bingo game and her all too memorable cue to ring out an emphatic “WOW” whenever mock amazement is required. For the duration of the trip, the occasional “WOW” could be heard ringing out from the dinner tables. Another amazing day in Antarctica and fun was enjoyed by all. 22 FEB- 2 March 2020 Volume 2, Issue 14
Page 1 and 2: 22 FEB- 2 March 2020 Volume 2, Issu
Page 3 and 4: TABLE OF CONTENTS The Voyage Meet t
Page 5 and 6: 4 Shelli Ogilvy Assistant Expeditio
Page 7 and 8: The Seven Sisters of Szczecin David
Page 9 and 10: Day 2 - Rolling Our Way South 23 Fe
Page 11 and 12: Day 3 - On Our Way to Antarctica! 2
Page 13 and 14: Drake Passage Drake Passage © Sand
Page 15: Day 4 - Our First Day in Antarctica
Page 19 and 20: When and How the Earth Got Cold Dav
Page 21 and 22: Port Charcot @Sandra Petrowitz Gent
Page 23 and 24: Day 7- The Final Stop Among the Sou
Page 25 and 26: Detaille Provisions Deception Islan
Page 27 and 28: Gentoo & Adelie @AmandaDalsgaard Fu
Page 29 and 30: Whalers Bay Whalers Bay @SandraPetr
Page 31 and 32: Day 9- The Beagle Channel 1 March 2
Page 33 and 34: King of the Southern Winds Sandra O
Page 35 and 36: By the Numbers… 34 Voyage Statist

South Shetlands & The Antarctic Peninsula 22 Feb 2020 - 14

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