AN EARLY CRETACEOUS FORE-ARC BASIN IN THE GOLFO-DE-PENAS REGION, SOUTHERN CHILE

A 4000 metre thick fining-up succession of conglomerates, sandstones a nd mudstones on the northwestern edge of the Golfo de Penas, southern Chile, is defined as the Puerto Barroso Formation. It probably formed in a forearc basin where a fan delta built across a narrow coastal pla in into a shallow marine environment during the Barremian to Aptian. T he basin is situated to the west of contemporaneous arc, bark arc and epicratonic basins and is the only documented forearc basin of this ag e in southern South America.