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O. H. Pilkey

Publications and source records attributed to O. H. Pilkey.

4 recordsLinked to original sources
USGS1982

Mud transportation on a steep shelf, Rio de La Plata shelf, Puerto Rico

Hurricanes David (August 29-30, 1979) and Frederick (September 2-5, 1979) caused major flooding of the Rio de La Plata in northern Puerto Rico. A thin mud layer was deposited across the narrow insular shelf adjacent to the river mouth. Within 5 months, fair-weather shelf-winnowing processes moved the mud layer entirely from the shelf, 0.5 to 2 km to the shelf break at the 50-m contour and beyond. The process of mud movement is termed 'mud hopping.' ?? 1982 A. M. Dowden, Inc.

Geo-Marine Letters↗
USGS1981

The Georgia Embayment continental shelf: stratigraphy of a submergence.

The Holocene-Pleistocene sediment veneer is thin, generally less than 4m thick. Lagoon sediments deposited during the last regression or the Holocene transgression occur in patches on the inner and central shelf. During each transgression or submergence, the surficial sand sheet is recharged with a new biogenic carbonate fraction along with the addition of small amounts of clastic sediments derived from 'overrun' estuaries and erosion of underlying Tertiary sediments. The stratigraphy based on the vibracores supports the concept of cross-shelf migration of the shore face-barrier island systems in response to rising sea level. -from Authors

Geological Society of America Bulletin↗
USGS1979

Relationship between physical condition of the carbonate fraction and sediment environments: Northern Puerto Rico shelf

Each of three sediment types recognizable on the northern Puerto Rico shelf and beaches is characterized by calcareous material in different physical condition. Dark terrigenous sand is accumulating at a relatively rapid rate and has a carbonate fraction containing fresh-appearing angular particles. The pure-carbonate skeletal-sand sediment type has a much lower rate of deposition, and its old-appearing calcareous particles have a dull surface luster. The third sediment type, a mixture of the first two, is largely from beaches and is characterized by highly polished, very well-rounded grains. Differences in length of sea-floor exposure and intensity of abrasion appear to be responsible for the variable physical condition of the carbonate fractions. We suggest that on other shelves having less distinctive sedimentary regimes, the physical condition of the carbonate grains could be used to interpret present shelf processes.

Puerto Rico↗