Tristan da Cunha Island Group and Gough Island
Tristan da Cunha Island Group 37° 06' S, 12° 18' W
The Tristan da Cunha group contains three volcanic islands resting on the east slope of the mid-Atlantic ridge midway between South Africa and Brazil. Tristan Island, 111 kmē, the youngest island in the group (1 million years), is still considered active with the most recent eruption occurring in 1961-62. Tristan consists of a 2060 m high conical volcanic peak with steep inclines that fall away to a more evenly inclined area of 600 m to 900 m in elevation. The coast is defined by sea cliffs up to 600 m in height, broken occasionally by low coastal strips. The rest of the islands are eroded volcanic cones which were once similar in size to Tristan Island. Nightingale Island is the oldest of these (18 million years), and most heavily eroded.
The Tristan da Cunha group was discovered by Portugese Admiral Tristado d'Ancunha in 1506.
Gough Island 40° 32'S, 09° 95'W
Gough Island, not fomally a member of the Tristan da Cunha Group, lies 425 km southeast of Tristan Island and is composed of volcanic lavas and ash. Gough's latest volcanic activity was about 2400 years ago. Gough rises over 910m and consists of a central plateau with several mountain peaks. The coastline consists of sea cliffs of 300m to 450m in height with narrow boulder beaches and no sheltered harbor. The southern end of Gough is the only area below 300m.
Gough Island was discovered in the early 16th century by the Portuguese navigator, Goncalo Alvarez. Little was heard of the island subsequently, until it was resighted by Captain Gough of the Richmond, a British ship, in 1731. It became known to British and American sealers and whalers, who preferred the name Gough Island.
Gough Tree Ferns Blechnum palmiforme) with Phylica arborea in the background.