Geology Reference
In-Depth Information
volcanic arc sources, the Dothan is composed of
The Sixes terrane is exposed just north of Cape
oceanic continental slope rocks of turbidite sands and
Blanco and in a small sheet south of Roseburg. It
muds with some deep water cherts. The Gold Beach
consists of Jurassic and Cretaceous mudstones, sand-
terrane is a "melange" or mixture of upper Jurassic
stones, and conglomerates chopped up by faults and
Otter Point Formation silts and sands mixed with lavas,
studded with huge separate blocks of blueschist and the
breccias, chert, and even schists. Overlying that terrane,
distinctive high-grade metamorphic rock eclogite. Near
the upper Cretaceous Cape Sebastian sandstone and
Roseburg, blocks of the middle Cretaceous Whitsett
Hunters Cove siltstone reflect storm wave conditions
limestones with corals and deep water shales along
with turbidite sands and shales. Bounded by a fault, the
cohesive block of the Gold Beach terrane may have
been moved north out of California in Tertiary time.
