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West Java region currently marks the transition between frontal subduction beneath Java and oblique subduction beneath Sumatra, to the west. Howevex, the region has been continuously active tectonically since rifting in the Eocene. The Eocene rifting, as throughout SE Asia, was probably related to the incipient collision between India and Asia (eg. Tapponier et al. 1986) and involved a significant influx of coarse clqsiic sediments. 7 he Oligocene-Recent history is more dominated by subduction-related volcanism and limestone deposition. The Bayah and Honje Highs are Tertiary structural highs located on the south coast of West Java, Indonesia, situated at the margin of the Malingping Lo'w (Fig. 1). The Honje High comprises mainly Miocene volcanoclastics flanked by Pliocene sediments to the west and Eocene strata to the east. Together with the adjacent Sunda Strait strike-slip basin, it probably formed in response to movement along the Sumatra strike-slip fault (Fig. 1). In the Sunda Strait and east and west of the Honje horst structure, and north and south of west Java (Malod et al. 1996) are a series of moderately dipping half grabens which trend N-S. These are clearly visible on seismic in the Malingping block offshore to the south of the Honje High (Fig. 1). The Bayah High comprises large E-W trending anticlines cored by Eocene clean coarse-grained sandstones (Figs. 1 & 2). Understanding of the timing of major events and the hydrocarbon potential offshoi-e SW Java, has been assessed by field investigation, and by Geosecbalancing and restoration of offshore reflection seismic line TQF-106 (Fig. 1). Additional input came from vitrinite reflectance (VR) data, fission track (FT) analysis, micropaleontology, amd from drill core data obtained from the Ujung Kulcin 1A well.