UPDATE 1-Colombia sees proven oil reserves rising

* Colombia could add as many as 6 bln barrels oil by 2020

* June oil and gas auction could result in 60 licenses

* Delegation to meet 23 Canadian companies this week

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By Pav Jordan

TORONTO, Feb 3 (Reuters) - Colombia could add as much as 6 billion barrels of oil to its reserves over the next decade if exploration holds at the current pace and state-controlled Ecopetrol ECO.CN boosts recovery rates, a top energy official said on Wednesday.

Colombia's National Hydrocarbons Agency will auction nearly 200 oil and gas exploration blocks in June as part of a program that began in 2004.

The sales are likely to boost proven oil and gas reserves from a current 1.5 billion barrels of oil equivalent as investment picks up into one of Latin America's fastest growing energy sectors.

"The optimistic scenario would be that we'd go to in excess of 6 billion barrels of oil between now and 2020 and that would bring us to a very comfortable position," agency director Armando Zamora said in Toronto during the first leg of a road trip to present the auction to Canadian investors.

He said the official goal was to add 4 billion barrels in the decade.

Zamora said the June auction of 198 oil and gas exploration blocs would likely result in a third of those being licensed, or around 60. That would come on top of the 70 or so licenses granted for oil and exploration in Colombia from the auction of about 200 blocs since 2004.

Colombia has seen a resurgence in interest in its oil and gas industry in recent years after fiscal reforms earlier this decade loosened investment terms.

The sector has also flourished under President Alvaro Uribe, who is popular for his U.S.-backed crackdown on the Marxist rebels who once bombed oil pipelines with impunity.

Many oil fields are guarded by the Colombian army and investment has streamed into the country as cities and highways became safer. Zamora said rebels are no longer the chief concern of investors.

Touting enthusiastic participation by Canadian and Chinese oil companies in particular, Zamora said foreign investment in the sector would likely exceed expectations, coming in at more than $4 billion in 2010 after dipping to $3 billion last year. Investment in Colombian oil and gas from abroad topped $3.5 billion in 2008.

"Given increased activity and contractual commitments, it will probably be in excess of $4 billion," he said. "I mean the confidence is returning, the financing is growing, the commitments are there, the services companies are also moving in."

Ecopetrol, 89.9 percent controlled by the state and listed on the Bogota and New York markets, invests a further $6 billion annually.

The company, which accounts for most of Colombia's production, is working on improving recovery rates at its oilfields, and Zamora said technological improvements might significantly add to Colombia's output.

"Some of the scenarios that we're on could bring us to 150 exploration wells per year and statistically that could lead to an average 40 percent success rate, so 60 successful wells, with an average, if we are conservative, of 10 million barrels (output)," Zamora said.

"That would take us to our rate of addition of 500-600 million barrels per year and that's quite a lot if you can sustain that."

Zamora will visit the United States, Brazil, Australia, Europe and Asia over the coming months.

($1=$1.06 Canadian)

(Reporting by Pav Jordan; Editing by Frank McGurty)