SEQUENCE is being designed to rapidly simulate the first-order evolution of continental margin morphology over long geologic time periods. To meet this requirement, the shelf and slope component models for SEQUENCE are 1-D, Eulerian, finite-difference models that produce 2-D, dip-line simulations of shelf and slope evolution. Both are relatively fast and encompass the physiographic provinces in...

abstract one of the problems in design of irrigation structures is sedimentation control in the inlet to the irrigation networks. water quality for agriculture requires that the sediments be controlled and reduced to the permissible limit at their entrance point to the turnouts and irrigation networks. this is possible by constructing a sedimentation basin. the bigger the basin, the best the re...

The north flowing Falkland / Malvinas Current has generated sediment drifts at a depth of 1200-1600 m in the Patagonian middle continental slope out of early Holocene hemipelagics, late Pleistocene ice rafted clastics, and Neogene fluvial sediments. Possibly there may be two generations of drifts, Pleistocene on the outer middle slope and Holocene on the inner shelf. The ice rafted debris origi...

Interactions between organic and detrital mineral phases strongly influence both the dispersal accumulation of terrestrial carbon (OC) in continental margin sediments. Yet complex interplay among biological, chemical, physical processes limits our understanding how organo-mineral interactions evolve during sediment transfer burial. In particular, diverse OC sources hydrodynamic hinder assessmen...

Methanogens are implicated in the production of methane that accumulates in marine sediments. However, the factors that control the distribution of the microbial communities that influence the presence of methane in these sediments are not well understood. Our objective is to determine the quantity, diversity, and distribution of microbial communities in the context of abiotic (e.g., grain size...

Sulfate reduction rates in the surface sediments from 17 stations from an along-slope transect (1,300 m) and from a cross-slope transect (855–4,766 m) were determined in the continental margin sediments of the Benguela Upwelling system. Profiles at all sites in the upwelling area showed increasing sulfate reduction rates from near zero at the surface to a peak at 2–5 cm (up to 29 nmol cm23 d21)...

Escherichia coli bacteria are commonly used as indicator organisms to designate of impaired surface waters and to guide the design of management practices to prevent fecal contamination of water. Stream sediments are known to serve as a reservoir and potential source of fecal bacteria (E. coli) for stream water. In agricultural watersheds, substantial numbers of E. coli may reach surface waters...

The Tennessee Valley Authority Kingston coal ash spill in December 2008 deposited approximately 4.1 million m(3) of fly ash and bottom ash into the Emory and Clinch River system (Harriman, Tennessee, U.S.A.). The objective of this study was to investigate the impact of the ash on surface water and sediment quality over an eighteen month period after the spill, with a specific focus on mercury a...

This work considers a landslide caused by the shear band that emerges along the potential slip (rupture) surface. The material above the band slides downwards, causing the band to grow along the slope. This growth may first be stable (progressive), but eventually becomes dynamic (catastrophic). The landslide body acquires a finite velocity before it separates from the substrata. The correspondi...

We have studied the magnetic properties of wet and dry late Pleistocene Lake Lisan sediments and the Holocene Dead Sea sediments. Our initial prediction was that the properties of both would be quite similar, because they have similar source and lake conditions, unless diagenetic change had occurred. Rock magnetic and paleomagnetic experiments revealed three stages of magnetization acquisition....