Age model and stable isotopes of sediment cores from north-central Chile and south-central Chile

Terrigenous sediment supply, marine transport, and depositional processes along tectonically active margins are key to decoding turbidite successions as potential archives of climatic and seismic forcings. Sequence stratigraphic models predict coarse-grained sediment delivery to deep-marine sites mainly during sea-level fall and lowstand. Marine siliciclastic deposition during transgressions and highstands has been attributed to sustained connectivity between terrigenous sources and marine sinks facilitated by narrow shelves. To decipher the controls on Holocene highstand turbidite deposition, we analyzed 12 sediment cores from spatially discrete, coeval turbidite systems along the Chile margin (29° - 40°S) with changing climatic and geomorphic characteristics but uniform changes in sea level. Sediment cores from intraslope basins in north-central Chile (29° - 33°S) offshore a narrow to absent shelf record a shut-off of turbidite deposition during the Holocene due to postglacial aridification. In contrast, core sites in south-central Chile (36° - 40°S) offshore a wide shelf record frequent turbidite deposition during highstand conditions. Two core sites are linked to the Biobío river-canyon system and receive sediment directly from the river mouth. However, intraslope basins are not connected via canyons to fluvial systems but yield even higher turbidite frequencies. High sediment supply combined with a wide shelf and an undercurrent moving sediment toward the shelf edge appear to control Holocene turbidite sedimentation and distribution. Shelf undercurrents may play an important role in lateral sediment transport and supply to the deep sea and need to be accounted for in sediment-mass balances.

Foreign aid : questions on the Central American regional program need to be resolved : report to the Honorable Patrick Leahy, United States Senate /

"B-221422"--P. [1].

Central America aid : status of the Trade Credit Insurance Program : fact sheet for the Honorable Patrick Leahy, U.S. Senate /

"B-221422"--1st. prelim. p.

Program planning document highway vehicle alternative fuels utilization program (AFUP).

April 1978.

Convention between the United Kingdom and France respecting commercial relations between France and the British Protectorates of East Africa, Central Africa, and Uganda.

"Signed at London, February 23, 1903. (Ratifications exchanged at London, March 27, 1905.)"

The central composition of the national capital and the public buildings program /

Mode of access: Internet.

National Voluntary Laboratory Accreditation Program : commercial products testing /

"July 1995."

Solar energy, program summary document.

Report covers fiscal year.

Skeleton outline of a plan for developing the Delta-Mendota irrigation water supply and salt-water repulsion in the Sacramento-San Joaquin Delta Region, Central Valley Project, California /

Mode of access: Internet.

Geohydrology and model analysis for water-supply management in a small area of west-central Kansas /

Mode of access: Internet.

Central flow control software design document.

Final report, January 1979.