GeoPark declines to raise offer for Frontera's Colombia oil and gas assets

March 9 (Reuters) - Energy firm GeoPark GPRK.N on Monday decided not to raise its offer for the Colombian oil and gas assets of Frontera Energy FEC.TO, after Frontera deemed a competing offer from Parex Resources to be "superior."

GeoPark had in January announced a definitive agreement to acquire all of Frontera's oil and gas exploration and production assets in Colombia for $375 million.

Toronto-listed Frontera said last week that its board and advisors determined the offer from Calgary-based Parex was a "superior proposal."

The Parex offer , first announced in February, is valued at $500 million in cash, including the assumption of debt and a contingent payment of $25 million.

Parex also said the combination would create the largest independent Colombian-focused energy company. The two firms are already partners in Colombia's VIM-1 block.

Frontera, one of Colombia's largest private producers, holds 17 exploration and production blocks, including the Quifa and Cubiro fields. The company reported average production of 38,934 barrels of oil equivalent per day at the end of the third quarter last year.