A model for the high-frequency backscatter angular response of gassy sediments is proposed. For the interface backscatter contribution we adopted the model developed by Jackson et al. [J. Acoust. Soc. Am. 79, 1410-1422 (1986)], but added modifications to accommodate gas bubbles. The model parameters that are affected by gas content are the density ratio, the sound speed ratio, and the loss para...

Floodplain soils and reservoir sediments are known for their fine-grained structure rich organic-matter substances; therefore, they able to sorb metals other potential pollutants, which is characteristic of sink function [...]

Traditional ichnofabric-descriptive (semiquantitative) schemes rely upon subjective estimates of the degree to which original sedimentary fabrics have been disrupted. This paper presents an objective method of quantifying bioturbation in hemipelagic sediments based on a thin-section image-analysis technique. In order to perform these analyses, optical or backscattered electron micrographs are p...

Currently, few studies have investigated sediment phosphorus (P) pools or identified the chemical processes important in the P cycle of fine-grained carbonate sediments, particularly in coastal estuaries with high organic matter. To determine the role of fine-grain calcium carbonate and high organic matter on sedimentary P, we investigated the solid-phase P pools in seagrass sediments of north-...

We analyzed the abundance and distribution of branched glycerol dialkyl glycerol tetraethers (brGDGTs) in grain size fractions of 7 globally distributed river flank sediments and catchment soils in order to determine if and how the initial soil-brGDGT signature is influenced by hydrodynamic sorting upon entering a river and during subsequent transport from land to sea. BrGDGTs are hypothesized ...

Surface oil seeps from Alasht, Lapur and Jenesem share many compositional affinities including distributions and concentrations ofnormal alkanes, terpanes and steranes. These oils also show many similarities with that of Jurassic sediments (Shemshak Group, KlarizFormation) systematically sampled from the Galandrud Coal Mine. Recent geochemical studies in this area indicated that theShemshak Gro...

The Gaza Strip constitutes the south-western part of Palestine. The loess deposits were observed in the Middle and Gaza Governorates in Gaza Strip. This study carried out in the Wadi Gaza where Quaternary loess well crops out. Twenty three samples were collected from nine observation sites in the study area, and performed a textural, calcium carbonate and organic matter content studies. The loe...

surface oil seeps from alasht, lapur and jenesem share many compositional affinities including distributions and concentrations ofnormal alkanes, terpanes and steranes. these oils also show many similarities with that of jurassic sediments (shemshak group, klarizformation) systematically sampled from the galandrud coal mine. recent geochemical studies in this area indicated that theshemshak gro...