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New biostratigraphic analyses of approximately 200 outcrop samples and reinterpretation of the biostratigraphy nearly 100 wells distributed across Indonesian western New Guinea enables reconstruction of the palaeogeography of the region from the Silurian to present day. Biostratigraphic ages and palaeodepositional environments were interpreted predominantly from occurrences of planktonic and larger benthic foraminifera. Palaeogeographic reconstructions reveal two major transgressive-regressive cycles in regional relative sea-level with peaks interpreted to occur in the Late Cretaceous and Late Miocene. During the Late Paleozoic and Early Mesozoic terrestrial deposition was prevalent across much of western New Guinea as it formed part of the northern promontory of the Australian continent, termed the Sula Spur. From the Late Jurassic the first regional transgressive event resulted in increasing water depths until the Late Cretaceous. Carinate planktonic foraminifera are widespread in sediments of this age encountered in wells and outcrop across the entire region. A regressive event from the Late Cretaceous into the Paleogene resulted in widespread shallow water carbonate platform deposition by the Middle to Late Eocene. A minor transgressive event is recorded during the Oligocene but was cut short by collision between the Australian continent and intra-Pacific island arcs in the Early Miocene causing regional uplift in the region and formation of a subaerial unconformity. Following uplift, carbonate platforms established in shallow water areas depositing youngest units of the New Guinea Limestone Group. A second transgressive event, initiating during the Middle Miocene, reached its peak in the Late Miocene this was followed by a further regression culminating in the present day topographic expression of western New Guinea.

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Hydrocarbon exploration in Eastern Indonesia region is mainly concentrated in the related convergent area such as Timor Basin. This area is characterized by the development of complex imbricate thrust-fold-belt deformation involving sedimentary sequence from the Australia continental margin. However, the exploration has not been successfully found the potential economic reserve. Our study utilized extensive and detailed fieldwork campaign  presents the structural style on the onshore region of the Timor Basin. Thick-skinned and thin-skinned thrust faults are both presents in West Timor area divided by the syn-orogenic basin. The change in decolement surface is likely to be caused by inversion structures under the thrust sheets. Our present interpretations indicate that these inversion anticlines structure are likely to occur both onshore and offshore.