Cape Lookout, Elephant Island

10 January

Cape Lookout, Elephant Island

After leaving Point Wild and its great whale-watching last evening, there were still whales everywhere – we saw 30 fin whales and 5 humpbacks within half an hour, then we passed another 30 fins around bedtime. They are concentrated in areas where presumably krill is dense. It’s terrific to see them in these numbers; gives us an idea what the cetacean density was like all over the Antarctic before 20th Century whaling took out 90% of them.

We had to make a large detour around an area of ice last evening, with a helpful report on a clear channel from a Chilean base supply ship that was within sight after dinner, but when we neared Table Bay in the morning there was too much ice to land. It was a big letdown for the geology buffs who’d really hoped to see the blue schist there. Always ready with an alternative plan, though, our expedition leader and geologists agreed to sail on to Cape Lookout.

Seas and winds were calm and the icebergs sparse so it was a fairly easy landing onto sea-smoothed bedrock at a low spit between jagged seastacks and a glacier face. The one fur seal harem was guarded by a rather large, though mellow, bull, and the Chinstrap Penguins were resting, nesting, and trotting in and out of the water all around. Intrepid rock hounds and hikers worked down the beach past the glacier face to a point, and also up the side of the glacier to a rocky saddle and partway up a ridge. Small bergs and bergy bits were marooned on the opposite side of the spit from our landing, making a great backdrop for penguin photography and a good haunt for resting seals.

The island, although relatively small (about 25 by 20 km), shows a gradual change in metamorphism from very low grade in the north to epidote amphibolites facies in the south, with the famous blue schists in between. Here the rock was folded amphibolites and gray schists full of pink metachert layers and albite porphyroblasts. The great bonus of this landing was that among all the green schist underfoot, Rudolph discovered one pumpkin-sized rock of blue schist right at the landing! It must have washed ashore encased in a block of ice.

The afternoon landing was at nearby Gibbs Island, where only two boatloads could go ashore at a time on the narrow cobble spit between two steep island masses. Chinstrap Penguins were nesting on improbably steep slopes and a few Macaroni Penguins and Gentoos were resting here and there. A leopard seal slept on one of the innumberable pickup truck-sized bergy bits that were rafted up against the far side of the spit. Graceful pale gray seabirds called Southern Fulmars nest on the high ledges and flutter all around the heights. Little dark brown Wilson’s Storm-petrels zipped over and around the boulders like swallows to their crevice nests.

Zodiac cruising was good, with some mellow humpback whales nearby, and dramatic cliff-forms with sea caves and backlit meltwater falls cascading into the sea. The geologists admired a serpentinized dunite along the Gibbs Island shear zone. This ultramafic body, originated in the earth’s mantle, was apparently incorporated in the accretionary prism that constitutes the surrounding islands.

Word was that the excellent weather was forecast to change overnight. The ship set out across Bransfield Strait toward the Antarctic Peninsula as dusk settled, with our fingers crossed for a continental landing in the morning.

– Kate Spencer, Staff Naturalist; Cheesemans’ Ecology Safaris