The source, transportation, and deposition of beach sediment in southern California.

Mode of access: Internet.

Modelling syntectonic sedimentation: combining a discrete element model of tectonic. Deformation and process-based sedimentary Model in 3D.

This paper presents a new numerical program able to model syntectonic sedimentation. The new model combines a discrete element model of the tectonic deformation of a sedimentary cover and a process-based model of sedimentation in a single framework. The integration of these two methods allows us to include the simulation of both sedimentation and deformation processes in a single and more effective model. The paper describes briefly the antecedents of the program, Simsafadim-Clastic and a discrete element model, in order to introduce the methodology used to merge both programs to create the new code. To illustrate the operation and application of the program, analysis of the evolution of syntectonic geometries in an extensional environment and also associated with thrust fault propagation is undertaken. Using the new code, much more complex and realistic depositional structures can be simulated together with a more complex analysis of the evolution of the deformation within the sedimentary cover, which is seen to be affected by the presence of the new syntectonic sediments.

Calcium carbonate, sedimentation and mass accumulation rates at DSDP Site 85-572

At Site 572, located at 1°N, 114° W (3903 m water depth), we recovered a continuous hydraulic piston cored section of upper Miocene to upper Pleistocene pelagic sediments. The sediment is composed of biogenic carbonate and silica with nonbiogenic material as a minor component. Detailed analysis of the calcium carbonate content shows that the degree of variability in carbonate deposition apparently changed markedly between the late Miocene and Pliocene at this equatorial Pacific site. During this interval carbonate mass accumulation rates decreased from 2.6 to 0.8 g/cm**2 per 10**3 yr. If we assume that variations in CaCO3 content reflect changes in the degree of dissolution, then the detailed carbonate analysis would suggest that the degree of variability in carbonate deposition decreases by a factor of 5 as the dominant wavelength of variations increases significantly. However, if the variability in carbonate concentration is described in terms of changes in mean mass accumulation, calculations then suggest that relatively small changes in noncarbonate rates may be important in controlling the observed carbonate records. In addition, the analysis suggests that the degree of variability observed in pelagic carbonate data may in part reflect total accumulation rates. Intervals with high sedimentation rates show lower amplitude variations in concentration than intervals with lower sedimentation rates for the same degree of change in the carbonate accumulation rate.

Sedimentation in submarine canyons in San Diego County, California, 1984-1987 : Coast of California storm and tidal waves study /

Mode of access: Internet.

Instructions for stream and valley sedimentation surveys /

Mode of access: Internet.

Some principles of accelerated stream and valley sedimentation.

Mode of access: Internet.

Some factors in the relation of stream and valley sedimentation to flood-control problems.

Mode of access: Internet.

Preliminary report on the visual tube method for sedimentation analysis of sands : a study of methods used in measurement and analysis of sediment loads in streams /

Mode of access: Internet.

Submarine topography and sedimentation in the vicinity of Mugu Submarine Canyon, California.

Mode of access: Internet.

Mugu Lagoon and its tributaries : geology and sedimentation /

Mode of access: Internet.

Erosion and sedimentation in the Illinois River Basin : final report /

"Printed: June 1992."

Sedimentation in Quincy Bay and potential remedial measures /

"ISWS/RI-108/87."--Cover.

Annotated bibliography on hydrology (1951-54) and sedimentation (1950-54), United States and Canada /

"Supplement to the Annotated bibliography on hydrology (Notes on hydrologic activities, Bull. no. 5) and Annotated bibliography on sedimentation (Sedimentation bull. no. 2)."

Annotated bibliography on hydrology (1951-54) and sedimentation (1950-54) United States and Canada.

"Supplement to the Annotated bibliography on hydrology (Notes on hydrologic activities, Bull. no. 5) and Annotated bibliography on sedimentation (Sedimentation bull. no. 2)"

Beryllium concentrations and deposition rates in ODP holes from the north Atlantic

Increases in the production rate of cosmogenic radionuclides associated with geomagnetic excursions have been used as global tie-points for correlation between records of past climate from marine and terrestrial archives. We have investigated the relative timing of variations in 10Be production rate and the corresponding palaeomagnetic signal during one of the largest Pleistocene excursions, the Iceland Basin (IB) event (ca. 190 kyr), as recorded in two marine sediment cores (ODP Sites 1063 and 983) with high sedimentation rates. Variations in 10Be production rate during the excursion were estimated by use of 230Thxs normalized 10Be deposition rates and authigenic 10Be/9Be. Resulting 10Be production rates are compared with high-resolution records of geomagnetic field behaviour acquired from the same discrete samples. We find no evidence for a significant lock-in depth of the palaeomagnetic signal in these high sedimentation-rate cores. Apparent lock-in depths in other cores may sometimes be the result of lower sample resolution. Our results also indicate that the period of increased 10Be production during the IB excursion lasted longer and, most likely, started earlier than the corresponding palaeomagnetic anomaly, in accordance with previous observations that polarity transitions occur after periods of reduced geomagnetic field intensity prior to the transition. The lack of evidence in this study for a significant palaeomagnetic lock-in depth suggests that there is no systematic offset between the 10Be signal and palaeomagnetic anomalies associated with excursions and reversals, with significance for the global correlation of climate records from different archives.