TECTONIC MODEL FOR FORMATION OF COLUMBIA BASIN: IMPLICATIONS FOR OIL, GAS POTENTIAL OF NORTH CENTRAL OREGON.

The Columbia basin is a depositional basin of regional proportions occurring in North Central Oregon and South Central Washington. In this article it is proposed that the Columbia basin originated in early Cretaceous time by partial rifting of the Mesozoic continental margin. The authors interpret that the basin has subsided and accumulated sediment more or less continuously throughout Tertiary time. Although the rifting concept is not original with the authors, they amplify it and interpret its implications in detail for the southern part of the basin in Oregon.