Recently obtained airgun-sonobuoy wide-angle refraction and
reflection profiles provide data to study crustal velocities and
structures along the continental margin of northern California and
Southern Oregon.
In the thick sedimentary wedge at the base of the continental
slope, as many as five distinct layers can be seismically observed,
which range...
The R/V WECOMA cruise leg 6 emphasized the field work of the marine geology research program on "Patterns and processes of continental margin sedimentation." This program constitutes a mesoscale study of processes controlling hemipelagic sediment distribution and composition beneath the coastal upwelling, non-upwelling and pelagic regimes of the equatorial East...
This study examined the foraminifera and the ecologic conditions
of the benthic environment of the Oregon shelf and the uppermost slope
(75-550 m depth) between 143°45' N and 144°40' N. Seasonal collections
monitored the near-bottom marine environment and the sedimentary
substrate at 16 stations. The foraminiferal benthic fauna was
examined...
Understanding continental crust formation and modification is a fundamental and longstanding geologic problem. Influx of mantle-derived basaltic magma and partial melting of the crust are two ways to drive crustal differentiation. This process results in a low density upper crust and denser, more refractory lower crust, creating significant and vastly...
The distribution of surface sediments on the northern Oregon
continental shell is characterized by a nearshore sandy facies and an
outer shelf muddy facies, separated by a mid-shelf zone of mixed
sand and mud. Currents which have been measured at 130 centimeters
above the bottom indicate that the distribution of...