Publications

Northwards movements of the Indian Ocean plate relative to the Asian plate are postulated to be closely associated with north-south lateral compression in Western Indonesia. This compression was responsible for the formation of a meridional shear system in Java. This shear system has developed since the Late Cretaceous.In accordance with wrench fault tectonics concepts, an attempt has been made to prove the existence of an ordered wrench fault pattern in Java applying the reasonable values of Q! = 1 4 O p = 35 and? = 10 . All faults can be grouped into first-second- and third order wrench systems. Most of the folds belong to first order (primary) with some folds around Jakarta being ascribed to second order drag. In northeast Java almost all folds are of third order drag.Exposures of Pre-Tertiary and Lower Tertiary sediments in the Lok Ulo area and the shore line configuration of north Central Java are most probably controlled by first order wrench faults. Hydrocarbon aspects of the wrench fault system are well evidenced in the northeast Java basin, where the prolific hydrocarbon bearing structures known since the last century can be grouped inenechelon folds closely related to the third order left lateral wrench.A suite of westeast trending faults interpreted from gravity data are most probably related to the existence of the west-east trending arc trench system in Java, as a result of continuing northwards movemenis of the Indian Ocean plate during the Oligocene.