Korea's National Oil Corp Suspends Daewang Whale Drilling

Shift in Exploration Strategy

The Korea National Oil Corporation (KNOC) has made a significant decision to halt further drilling operations for the "Daewang Whale" structure in the East Sea deep-sea gas field. This move comes after extensive analysis of samples collected during the initial drilling campaign earlier this year, which revealed a gas saturation rate of only 6%, far below the projected 50–70%. The findings suggest that the gas discovered is not economically viable, leading the corporation to conclude that continued exploration is unnecessary.

Key Findings from Initial Drilling

During the first drilling phase, no recoverable gas was found within the Daewang Whale structure. The actual gas saturation rate measured at 6.3%, which is significantly lower than the initial projections. Moreover, the type of gas identified was "biogenic gas," resulting from the decomposition of organic matter such as fish and plankton, rather than "thermogenic gas," which forms under high heat and pressure conditions.

For oil or gas to be considered economically viable, four key geological conditions must be met: reservoir rock, cap rock, source rock, and a trap. However, the analysis showed that no "trap" was formed, which is essential for containing oil or gas. Additionally, there was no evidence of thermogenic gas migration from the source rock, further reinforcing the conclusion that the area is not suitable for future exploration.

Reservoir and Cap Rock Conditions

Despite these findings, some aspects of the reservoir and cap rock were consistent with initial estimates. The reservoir rock, initially projected to be 69 meters thick, measured 68.5 meters, while the cap rock, estimated at 209 meters, was actually 269.5 meters thick. The porosity rate also exceeded expectations, reaching 30.8% compared to the initial estimate of 18–30%.

Second Drilling Project Outline

With the results of the first drilling now finalized, the details of the second drilling project are beginning to take shape. KNOC reported that multiple foreign companies participated in the second drilling bid, which concluded on the 19th of last month. After reviewing the applications, the corporation plans to select a preferred negotiation partner if a suitable investor is identified.

Earlier in March, the corporation launched a bid to attract investment for the East Sea offshore block and extended the bidding period by three months at the request of potential investors. This indicates a strategic effort to secure international support for the next phase of exploration.

Future Exploration Plans

As KNOC has definitively ruled out further exploration of the Daewang Whale, the second drilling is expected to focus on one of the remaining structures. If the preferred negotiation partner challenges ActGeo’s analysis of the "seven promising structures," a comprehensive reevaluation of all structures may occur. However, even in this scenario, the likelihood of revisiting the Daewang Whale remains low.

This shift in strategy highlights the importance of accurate geological assessments and the need for economic viability in resource exploration. As the corporation moves forward, it will likely rely on international collaboration and advanced analytical techniques to identify more promising areas for future drilling activities.