| Title | Submarine canyon and fan systems of the California Continental Borderland |
| Author | Normark, W R; Piper, D J W; Romans, B W; Covault, J A; Dartnell, P; Sliter, R W |
| Source | Earth science in the urban ocean: the southern California Continental Bordeland; by Lee, H J (ed.); Normark, W R (ed.); Geological Society of America, Special Paper 454, 2009 p. 141-168, https://doi.org/10.1130/2009.2454(2.7) (Open Access) |
| Year | 2009 |
| Alt Series | Geological Survey of Canada, Contribution Series 20060258 |
| Publisher | Geological Society of America |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Area | California; United States of America |
| Lat/Long WENS | -121.0000 -117.0000 35.0000 32.2500 |
| Subjects | marine geology; sedimentology; geophysics; geochemistry; stratigraphy; continental margins; continental shelf; submarine features; submarine canyons; submarine fans; marine sediments; sediment
transport; sediment distribution; deposition; turbidites; debris flow deposits; depositional environment; depositional history; sea level changes; basins; turbidity currents; geophysical surveys; seismic surveys; seismic reflection surveys; seismic
profiles; sonar surveys; marine sediment cores; piston cores; geochemical analyses; stable isotope studies; oxygen isotopes; radiometric dating; radiocarbon dating; stratigraphic analyses; sediment transfer; rivers; tectonic environments;
sedimentation; California Borderland; Santa Barbara Basin; Santa Monica Basin; San Pedro Basin; Gulf of Santa Catalina basin; San Diego Trough; Hueneme Canyon; Redondo Canyon; Newport Canyon; La Jolla Canyon; Santa Clara delta; Mugu fan; Dume fan;
Phanerozoic; Cenozoic; Quaternary |
| Illustrations | sketch maps; profiles; digital elevation models; cross-sections; cartoons |
| Program | Geoscience for
Oceans Management |
| Released | 2009 01 01 |
| Abstract | Late Quaternary turbidite and related gravity-flow deposits have accumulated in basins of the California Borderland under a variety of conditions of sediment supply and sea-level stand. The northern
basins (Santa Barbara, Santa Monica, and San Pedro) are closed and thus trap virtually all sediment supplied through submarine canyons and smaller gulley systems along the basin margins. The southern basins (Gulf of Santa Catalina and San Diego
Trough) are open, and, under some conditions, turbidity currents flow from one basin to another. Seismic-reflection profiles at a variety of resolutions are used to determine the distribution of late Quaternary turbidites. Patterns of
turbidite-dominated deposition during lowstand conditions of oxygen isotope stages 2 and 6 are similar within each of the basins. Chronology is provided by radiocarbon dating of sediment from two Ocean Drilling Program sites, the Mohole test-drill
site, and large numbers of piston cores. High-resolution, seismic-stratigraphic frameworks developed for Santa Monica Basin and the open southern basins show rapid lateral shifts in sediment accumulation on scales that range from individual lobe
elements to entire fan complexes. More than half of the submarine fans in the Borderland remain active at any given position of relative sea level. Where the continental shelf is narrow, canyons are able to cut headward during sea-level transgression
and maintain sediment supply to the basins from rivers and longshore currents during highstands. Rivers with high bedload discharge transfer sediment to submarine fans during both highstand and lowstand conditions. |
| GEOSCAN ID | 222764 |
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