Between
peninsular Malaysia, Borneo, Sumatra and Java is the Sunda Shelf one of
the largest continental shelves on Earth (Tjia, 1980), which, during the
last glacial lowstand, was exposed above sea level as Sundaland
(Fig. 1A; Molengraaff, 1921). The inner part of Sundaland, where the
SEL is located, is more than 500 km from the Java–Sumatra trench, the
western margin of the Sundaland block (Fig. 1A) and is considered a tectonically
stable region with negligible isostatic crustal movement.