Extension Reef is a

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock out ...

which encompasses a large number of small islands and rocks, extending southwest from the south end of

Rabot Island Rabot Island is an island long and wide, lying south of Renaud Island in the Biscoe Islands. First charted by the French Antarctic Expedition, 1903–05, under Jean-Baptiste Charcot, who named it for Charles Rabot. Originally discovered by Jo ...

, in the

Biscoe Islands Biscoe Islands is a series of islands, of which the principal ones are Renaud, Lavoisier (named ''Serrano'' by Chile and ''Mitre'' by Argentina), Watkins, Krogh, Pickwick and Rabot, lying parallel to the west coast of Graham Land and extending ...

. It was first charted and named by the British Graham Land Expedition, 1934–37, under

John Rymill John is a common English name and surname: * John (given name) * John (surname) John may also refer to: New Testament Works * Gospel of John, a title often shortened to John * First Epistle of John, often shortened to 1 John * Second E ...

References

Reefs of Graham Land Landforms of the Biscoe Islands {{Biscoes-geo-stub