Palynomorph concentrations for water-column and sediment-water interface samples are presented for two coastal deltaic systems influenced by the range of tidal regimes to assess whether any taphonomic bias exists in pollen assemblages. The localities are the microtidally influenced Mobile-Tensaw River Delta, Alabama, United States, and the mesoto macrotidally influenced Rajang River Delta, Sara...

I present a numerical diffusion–advection-reaction model to simulate CO2 chemistry, d C, and oxidation of organic carbon and methane in sediment porewater. The model takes into account detailed reaction kinetics of dissolved CO2 compounds, H2O, H , OH , boron and sulfide compounds. These reactions are usually assumed to be in local equilibrium, which is shown to be a good approximation in most ...

The offshore displacement of commercial bottom trawling has raised concerns about the impact of this destructive fishing practice on the deep seafloor, which is in general characterized by lower resilience than shallow water regions. This study focuses on the flanks of La Fonera (or Palamós) submarine canyon in the Northwestern Mediterranean, where an intensive bottom trawl fishery has been act...

Hydro-induction sediment discharge technique (HSDT) aims to prevent reservoir sedimentation by withdrawing the discharge water from the reservoir bottom to suck up and discharge sediments, and by inducing vertical vortexes and undercurrents in the reservoir bay to keep sediments agitated and moving. The technique is facilitated with an innovative discharge conduit system having bottom intakes t...

[1] Systematic differences in sediment thermal and pore water chemical profiles from Integrated Ocean Drilling Program Site U1363 document mixing and reaction within the basaltic crust adjacent to Grizzly Bare outcrop, a site of hydrothermal recharge into 3.6 My-old basaltic crust. A transect of seven holes was drilled ~50 m to ~750 m away from the base of the outcrop. Temperatures at the sedim...

In most aquatic systems, concentrations of trace metals in suspended sediment and the top few centimeters of bottom sediment are far greater than concentrations of trace metals dissolved in the water column. Consequently, the distribution, transport, and availability of these constituents can not be intelligently evaluated, nor can their environmental impact be determined or predicted solely th...

The study of mechanisms that allow the formation of structures such as sand dunes and ripples at the bottom of a fluid flow plays a crucial role in the understanding of coastal dynamics. The modeling of these phenomena is particularly complex since we must not only solve the Navier-Stokes or Saint-Venant equations with equation for sediment transport, but also take into account the evolution of...

A dredged material disposal operation was monitored on a location in Lake Erie 8 km offshore Ashtabula, Ohio, June to November, 1975. Some 200 sediment cores were collected in the periods before and after dredging and analyzed for the grain-size distribution of the sediments. Two current meters and a wave sensor moored nearby monitored the movement of the water masses. The sediments were dredge...

− We can obtain the performance of the marine seismometer upon the sediment to know its coupling in the bottom sea. This paper deals with the coupling parameters in order to obtain the geophone response through the frequency. The use of the shake table and vibration calibrator allows to deduce the coupling transfer function between the geophone and the sediment sea without using a detailed mode...

The neodymium isotopic composition of the silicate fraction of Holocene pelagic sediments from the North Pacific define two provinces: a central North Pacific province characterized by unradiogenic and remarkably homogeneous end (--10.2 +_ 0.5) and a narrow circum-Pacific marginal province characterized by more radiogenic and variable end (--4.2 + 3.8). The silicate fraction in the central Nort...