Stock prices of oil- and gas-related companies went on a roller coaster ride Tuesday, amid investors’ interest in the discovery of possible oil reserves off the East Coast following President Yoon Suk Yeol’s announcement the previous day.

With the government approving exploratory drilling for a potential 14 billion barrels of crude oil and natural gas reserve at Yeongil Bay in Pohang, North Gyeongsang Province, investors flocked to energy-related shares listed on the Korean bourse.

While the project leader, Korea National Oil Corp., has remained unlisted, the daily trading volume of Korea Gas Corp. hit 1.48 trillion won ($1.1 billion), the highest since its shares were listed in 1999. The public gas company is expected to manage the produced gas from the reserve.

Shares of the state-run company closed at 39,400 won, up 700 won or 1.81 percent from the previous session’s 38,700 won. It spiked to 49,350 won earlier in the day, nearly hitting its upper circuit of 30 percent as it had done on the prior day, but later slumped to 38,750 won.

Natural gas supplier Daesung Energy’s stocks closed at 12,500 won, up 1,510 won or 13.74 percent, after reaching its day peak at 14,100 won. Daesung Energy had reached the upper limit on the previous day as well.

Shares of petroleum product manager Hung-gu Oil closed at 19,240 won, up 2,990 won or 18.40 percent. Earlier in the day, the shares nearly reached their cap of 21,100 won, surging to 20,950 won, but later plunged to 17,510 won during trading hours.

But shares of steel manufacturer Dongyang Steel Pipe and pipeline valve maker HS Valve reached their maximum permissible limit, 1,175 won and 8,630 won, respectively.

Even the shares of asphalt maker Korea Petroleum, unlikely to directly benefit from the project, surged to the upper circuit-breaker limit of 23,300 won.

Market analysts warned it was premature to determine the drilling project’s profitability or probability of success.

"It is still unsure about the project as it is in an early stage," Hana Securities analyst Yoo Jae-seon viewed. "The process has to be monitored for the time being, though anticipation may further grow.”

"The success rate of exploratory drilling is usually assessed to be at around 10 percent, but the government suggested 20 percent for the project, considering technological developments,” Yoo said. "As the project involves deep-sea drilling, the cost may be considerable.”

Other analysts questioned the lucrativeness of the project.

"The production volume should be differentiated from the size of the reserve," analyst Moon Kyeong-won from Meritz Securities viewed, referring to the figure of 14 billion barrels of crude oil and natural gas.

At Monday's briefing, the government explained the amount matches up to Korea's consumption of natural gas for up to 29 years as well as four years in terms of crude oil.

"Even if the project kicks off, it is uncertain whether the cost would be commercially feasible,” Moon said. “Private or foreign money could take part in the project as well.”