HOUSTON (Reuters) -Chevron ( CVX ) said on Wednesday it expects that a prolific oilfield in Guyana could hold more than the current estimate of 11 billion barrels of oil equivalent in recoverable resources.

"When you think about 11 billion barrels, big fields getting bigger, although we haven't forecast it, I would expect upside," Chevron ( CVX ) Vice Chairman Mark Nelson said at the company's investor day in New York City. 

Chevron ( CVX ) gained a 30% stake in the Stabroek Block in Guyana earlier this year when it acquired Hess after prevailing in a lengthy legal dispute with Exxon Mobil ( XOM ), which operates the block with a 45% interest. Chinese firm CNOOC holds the remaining 25%. 

Chevron's ( CVX ) investor day event provided financial guidance through 2030 incorporating Hess, and included a presentation slide showing production capacity growth over time in Guyana. Nelson said there was room for more exploration in Guyana and that Chevron ( CVX ) was eager to help.

"There's some deeper reservoirs to test, and we look forward to working with the partner to do that," he said.

In September, during a Barclays conference, Exxon Senior Vice President Jack Williams said 11 billion barrels was the "best number" the company had for an estimate of the resource, while more exploration would continue.

Separately, Exxon said on Wednesday that daily oil production at Stabroek had reached 900,000 barrels a day. The company eventually expects to have total output of 1.7 million bpd from eight developments in the country.

"Everything that we have shared today reflects the operator's view," Chevron's ( CVX ) Nelson said, referring to Exxon. "That's what a good partner would do."