The Sahul Shelf proper stretches northwest from Australia much of the way under the
Timor Sea towards
Timor, ending where the seabed begins descending into the
Timor Trough. To the northeast, the Sahul Shelf merges into the Arafura Shelf, which runs from the northern coast of Australia under the
Arafura Sea north to
New Guinea. The
Aru Islands rise from the Arafura Shelf. The Sahul Shelf is sometimes taken to also include the Rowley Shelf to the southwest of
Cape Leveque, girding the north coast of
Western Australia as far as
North West Cape. The existence of an extensive Sahul Shelf was suggested in 1845 by
George Windsor Earl who called it the "Great Australian Bank" and noted that
macropods (kangaroos) were found on Australia, New Guinea, and the Aru Islands. Earl also suggested the existence of the
Sunda Shelf (which he called the "Great Asiatic Bank") covering the western
Malay Archipelago and the
Malay Peninsula. In the 1970s,
biogeographers coined "
Sundaland" and "
Sahul" as contrastive names for the continental regions extending from the adjacent shelves. ==Geology==