Marine seismic data from the Blake Outer Ridge offshore Florida show strong “bottom simulating reflections” (BSR) associated with methane hydrate occurence in deep marine sediments. We use a detailed amplitude versus offset (AVO) analysis of these data to explore the validity of models which might explain the origin of the bottom simulating reflector. After careful preprocessing steps, we deter...

Crustal thickness is a critical parameter for understanding the processes of continental rifting and breakup and the evolution of petroleum systems within passive margins. However, direct measurements of crustal thickness are sparse and expensive, highlighting the need for methodologies using gravity anomaly data, jointly with other geophysical data, to estimate crustal thickness. We evaluated ...

The thickness of the free gas column below the base of the gas hydrate stability zone is a proxy for the pore pressure in the free gas bearing sediments underneath. In the study area the pore over-pressrues derived under this assumption range between 0 and 1430 kPa ± 30% which appear to be the typical maximum over-pressure that the gas hydrate sediments can withstand before hydro-fracturing occ...

The purpose of this paper was to compare two methods of fractionation of reactive phosphorus forms (RP) in bottom sediments of polymictic water reservoirs located in rural areas. As a criterion for estimation, quantities RP extracted in analyzed fractions versus the general content of Al, Fe and Ca were used. The sediments were collected in springtime, from rural areas with different land use i...

Here, we report a type strain AST-10 representing a novel species Sulfurimonas hongkongensis within Epsilonproteobacteria, which is involved in marine sedimentary sulfur oxidation and denitrification. Strain AST-10(T) (= DSM 22096(T) = JCM 18418(T)) was isolated from the coastal sediment at the Kai Tak Approach Channel connected to Victoria Harbour in Hong Kong. It grew chemolithoautotrophicall...

Seismic analysis of data from the Blake Outer Ridge indicates the presence of hydratebearing sediments overlaying gas-saturated sediments in this region. In an attempt to determine possible lateral and vertical variations of the hydrate and gas sediments, I performed a 2-D velocity analysis along two approximately perpendicular seismic lines. Subsequent determination of the seafloor and BSR ref...

This research covered an evaluation of the copper and cadmium concentrations in bottom sediments dredged from one of the ponds in Warsaw. The samples of sediments, soil, and plants were analyzed in terms of Cu and Cd content. The research concerned the heap of dredged bottom sediments from Wyścigi Pond, Warsaw, Poland. Two boreholes were made to obtain sediment cores with depths of A 162.5 cm a...

The accumulation of gas hydrates in marine sediments is essentially controlled by the accumulation of particulate organic carbon (POC) which is microbially converted into methane, the thickness of the gas hydrate stability zone (GHSZ) where methane can be trapped, the sedimentation rate (SR) that controls the time that POC and the generated methane stays within the GHSZ, and the delivery of met...

Heavy crude oil is known as oil that is highly viscous and of a higher density than that of conventional oil. Sand reservoirs containing heavy oil generally consist of unconsolidated sediments deposited at a shallow burial depth, with high porosity and permeability. In seismic exploration, acoustic impedance inversion is a commonly used tool in reservoir prediction. However, due to the unconsol...

To investigate bioturbation effects on cadmium (Cd) fluxes from overlying water to sediments, indoor microcosms were developed. The bioturbating organisms were freshwater tubificid worms. Three experimental conditions were studied during 56 d. The three conditions were contaminated water column ([Cd]: 20 microg/L) with or without worms and uncontaminated water column with worms. Cadmium vertica...