* Says protests caused brief outage at El-Sharara field
* Aims for 2.2 mln bpd output within five years
* Libya to increase refining capacity, look for shale gas (Adds detail on refining capacity)
By Emma Farge
VIENNA, Nov 7 Libya's National Oil Corporation (NOC) aims to boost oil output to 1.72 million barrels per day (bpd) by the end of March next year, its chairman said on Wednesday, but warned of the risk that strikes could interrupt production.
OPEC member Libya has lifted production much faster than analysts had expected after last year's civil war to a current level of around 1.6 million barrels per day.
But in recent months activists and local militia have sought to pursue political aims by disrupting operations in Libya's main industry and in July forced the closure of three major oil terminals.
"We had some drops in production. Welcome to democracy and freedom of expression. We had strikes and we expect more of that, but it is a healthy thing," NOC Chairman Nuri Berruien said at the North Africa Oil and Gas Summit.
He added on the sidelines of the conference that protests at the Zawiya refinery near Tripoli earlier this week had forced a one-day shutdown at the 200,000 bpd El Sharara field.
The refinery also was halted due to the protests and has resumed operations, according to a refinery spokesman.
Berruien said future rises in oil production would mostly come from existing fields. Libya will aim to boost production to 2.2 million bpd within five years, he said.
"We strongly believe a large amount of our future oil can be in already targeted mature fields," he said, adding that high oil prices and technological advances created a favourable environment.
He said the country also would explore its potential to produce unconventional gas, such as shale.
NOC plans to proceed next year with Libya's fourth licensing round, known as the Exploration Production and Sharing Agreement (EPSA), Berruien said without providing details.
Investing in new refining capacity will also be a priority for the NOC, he added.
Despite being one of Africa's top oil producers, Libya relies on imports for around three quarters of its gasoline consumption.
"We plan to upgrade and increase the capacities of existing refineries and to study different options of adding new refineries to increase gasoline and diesel with good specifications," he told the conference. (Editing by Alison Birrane and Jane Baird)