One seismic gig offshore Indonesia done, two more ongoing

Norway’s energy data and intelligence provider TGS is busy with 2D seismic survey reprocessing assignments off the coast of Indonesia. While the firm has wrapped up one of these jobs in the Sumatra basin, tying key discoveries in the region to open acreage, two more are ongoing, one in Seram Basin and the other offshore East Java.

The completed 7,756-kilometer line 2D reprocessing project used a modern broadband pre-stack processing workflow, covering a hydrocarbon basin with Miocene-Oligocene syn-rift clastic and carbonate plays. 

According to TGS, the survey spans both outboard and inboard areas adjacent to the North Sumatra 3D project, which includes the Pase sub-basin. Key calibration points are provided by recent discoveries, including Timpan-1, Layaran-1, and Tangkulo-1, located within the 3D area.

TGS believes that the integration of 2D and 3D data will improve the understanding of existing discoveries and wells along the basin’s southern and eastern margins. Proven plays in the area consist of Miocene carbonates, Miocene/Pliocene clastics, and the Oligocene syn-rift. The dataset also reveals an untested older syn-rift play. GeoStreamer technology enhances resolution at all depths, aiding in the analysis of basin development and deeper plays.

“By enhancing this legacy North Sumatra dataset through a modern broadband PSDM processing workflow, we can tie high-quality, modern seismic data to several of the region’s most significant discoveries of the last five years. This will enable the extension of key play concepts into open acreage, creating exciting exploration opportunities across this Indonesian basin,” said David Hajovsky, EVP of Multi-Client at TGS. 

TGS’ seismic acquisition project offshore Seram is expected to cover over 1,800 kilometers of new 2D data across the southeastern part of the basin, using a 12-kilometer-long offset streamer. This is TGS’s fifth seismic survey in Indonesia this year. 

Supported by industry funding, the project will utilize advanced processing techniques, including broadband pre-stack time migration (PSTM), pre-stack depth migration (PSDM), and 24 Hz full wave inversion (FWI), to achieve detailed subsurface imaging, according to TGS.

“Our latest seismic acquisition in Indonesia highlights TGS’s dedication to delivering exceptional subsurface imaging and fostering strong partnerships with key stakeholders in the region. In the Seram basin, we are focused on using high-quality acquisition and processing methods to improve imaging below the shallow carbonates in the Seram thrust belt, where there are clear indications of active petroleum systems,” Kristian Johansen, CEO at TGS commented.

On the other hand, the Norwegian company’s East Java basin 2D seismic reprocessing project will cover over 4,600 kilometers of seismic data in the southwestern part of the basin.

The project, also supported by industry funding, uses advanced processing techniques such as broadband PSTM, PSDM, as well as FWI to deliver imaging tailored to the region’s specific geological features.

“TGS is committed to delivering high-quality subsurface imaging in the East Java Sea. Our data in the region aims to provide new insights into the deeper basin structure and stratigraphy, targeting a broad range of geological features including conventional traps, carbonates, stratigraphic plays, and fractured basement,” underlined Hajovsky.

TGS’ first multi-client 3D survey in Indonesia, TBN10, covered over 1,600 square kilometers in 2010. Twelve years later, the company kicked off a 2D-cubed reprocessing project designed to help drive exploration across the South Makassar and North East Java regions in Indonesia.

The Norwegian player has secured several new jobs outside Indonesia as well, including a deal with Mauritania’s Ministry of Petroleum, Mines and Energy to integrate, enhance, and license additional subsurface data in Mauritania.