Deciphering the Fluviomarine Sedimentation Record of the Northern California Continental Shelf: A High-Resolution C-14 Geochronological Approach
Abstract
LONG-TERM GOALS The overarching goal of this research is to understand the variability of sediment accumulation rates and strata formation on continental shelves as influenced by sediment supply and dispersal, hydrodynamics, and tectonics. Investigating the controls on sedimentation patterns and rates on a range of temporal and spatial scales is necessary to link short-term sedimentary processes and the stratigraphic record. OBJECTIVES. The major objective of this research is to develop high-resolution C-14 geochronologies for piston cores collected in the STRATAFORM study area on the northern California continental shelf. C-14 (t1/2=5730 yr) geochronology allows for determination of sediment accumulation rates averaged on time scales ranging from several hundred to many thousands of years. Because sediment accumulation rates integrate a range of environmental/tectonic conditions, they provide a means to relate transport processes and stratigraphic products. Spatial and temporal variations in sediment accumulation rates on the shelf have been interpreted in consideration of sediment-source proximity and magnitude, oceanic circulation, and deeper stratigraphy revealed by seismic reflection profiles. In addition, C-14 dates have provided necessary chronological control for determining the frequency of sedimentary event layers (produced by floods and storms) preserved in shelf deposits. The results of this research are expected to (1) generate new insights into relationships between sedimentary processes and shallow stratigraphy and (2) provide parameters (i.e. accumulation rates) necessary for numerical models of strata formation..
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1999
- Accession Number
- ADA629847
Entities
People
- Christopher K. Sommerfield
- Wayne Rockwell Geyer
Organizations
- Woods Hole Oceanographic Institution