Neogene arc-continent collision in Sabah, Northern Borneo (Malaysia)

Abstract

The Neogene evolution of Sabah can be interpreted in terms of an arc-continent collision initiated during early Middle Miocene time and followed by intraplate shortening, the latter being active in this area at the present day. The volcanic arc of Late Oligocene-Middle Miocene age is imbricated with melanges and thrust northwestward on a polyphase-deformed turbiditic sequence of Late Cretaceous-Middle Miocene age (Crocker Range). Intraplate shortening is seen in the thrusting and folding offshore Sabah along the Palawan-North Borneo Trench, and also by broad open folds and strike-slip faulting in the previously sutured terranes. This collision can either be interpreted as the final stage of southward subduction of the hypothetical Proto-South China Sea, or the result of back thrusting of the Sulu volcanic arc resulting from the subduction of the Celebes Sea toward the north.