The Gimsan Basin sits in the Halten Terrace on the mid-Norwegian continental shelf, about 240 kilometers northwest of Trondheim. It shares the same neighborhood or trend as the Mikkel and Heidrun Field, the latter one of the region's long-running producers, making it part of one of the more established plays in the Norwegian Sea.
Well 6407/5-3S on the prospect Lakris is spudded and will be drilled in the Norwegian Sea within the Gimsan Basin within the Halten Terrace. The primary target is Upper Cretaceous Nise formation, and the secondary target Lower Jurassic Tilje formation (S&P, recent news). Any Hydrocarbons proven from the Nise reservoir will be a play opener. The other reservoirs to monitor are Lower Jurassic Åre and Tofte formations. Figure: The vertical black line indicates the prognosed vertical position of the well. The well is operated by Vår Energi under production license 1002. TGS has a recent dual azimuth dataset (24M01NWS_DAZ) that gives the targets at hand here good imaging quality.
The Halten Terrace is one of the most mature hydrocarbon provinces offshore Norway, shaped by Jurassic rifting that created tilted fault blocks and structural lows controlling source, reservoir, and trap distribution. The basin is charged by two distinct Jurassic source rocks: the organic-rich Upper Jurassic Spekk Formation, which generates oil, and deeper Lower Jurassic coaly intervals, which generate gas and condensate. This dual-source system means reservoirs can hold oil, gas-condensate, or mixed-phase hydrocarbons depending on structural position and migration history, with hydrocarbons typically migrating along fault systems and carrier beds from the deep basin kitchens to structural highs on the terrace.
Reservoirs across the region are dominated by Middle Jurassic sandstones, principally the Garn, Ile, Tilje, and Åre formations, deposited in marginal marine, deltaic, and shallow marine settings with strong porosity and permeability where burial and diagenesis have been favorable. Seal capacity comes from regionally extensive Upper Jurassic and Lower Cretaceous marine shales. With source, migration, reservoir, trap, and seal all well proven, the Halten Terrace remains a well-established petroleum system.
Despite the proven nature of the petroleum system, exploration success is far from uniform across the terrace. The central and northeastern parts of the Halten Terrace contain several commercial fields where reservoir quality remains relatively preserved and pore pressures are manageable. However, moving westward toward the deeper parts of the basin, conditions become increasingly challenging. Previous wells have encountered disappointing results despite valid structural closures and evidence of charge.
For the “Lakris” prospect specifically, the prospect sits in an area where the petroleum system is demonstrably active, but where deeper burial, elevated pressures, and reservoir preservation risks become increasingly important. Success would further demonstrate the viability of the western Halten Terrace fairway, while failure would reinforce the view that reservoir and pressure-related challenges remain key constraints on exploration in this part of the Norwegian Sea. The new 6407/5-3S well will test Cretaceous Nise formation as a primary target, a potential play opener for this area.
For companies evaluating opportunities in this area, high-quality regional subsurface data will be key to understanding the broader geological context. TGS has the seismic coverage and imaging expertise to help operators move confidently across both mature and frontier areas. Visit TGS seismic data library or contact us to schedule a data showing.
Norwegian Sea Geology - Hotspot: https://hubs.ly/Q04tWjzH0
MP-FWI, the Key to Unlock Potential Prospects in the Norwegian Sea - A Case Study from the Outer Vøring Area: https://hubs.ly/Q04tWkSv0
Validating Opportunistic 4D as a Proof of Concept for Seismic Monitoring: https://hubs.ly/Q04tWl4P0