Consulta: creatorFacets:"Vernant, Antoine-mathieu"
Registros recuperados: 2
Data/hora: 27/07/2024 03:14:03

Detection of free gas and gas hydrate based on 3D seismic data and cone penetration testing: An example from the Nigerian Continental Slope
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Sultan, Nabil; Voisset, Michel; Marsset, Tania; Vernant, Antoine-mathieu; Cauquil, E; Colliat, J; Curinier, V.
We present a new method to characterize free gas, gas hydrates and carbonate concretions occurrence which are considered as high-risk factors for sub-sea developments in the Niger delta. This method is based on the combination of 3D seismic data to the geotechnical site characterizations using piezocone CPTU tests (Cone Penetration Test with additional measurement of the pore water pressure). A special processing of the 3D seismic data has enabled the determination of the interval compressional velocity. Using the effective-medium theory, velocity anomalies (negative and positive) within the first 15 m were translated in gas hydrate and free gas distribution. The calibration of the P wave velocity anomalies was done thanks to in-situ geotechnical testing...
Tipo: Text
Palavras-chave: Piezocone; Niger delta; Gas hydrate; Free gas; Effective medium theory.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2610.pdf

Hydrate dissolution as a potential mechanism for pockmark formation in the Niger delta
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Sultan, Nabil; Marsset, Bruno; Ker, Stephan; Marsset, Tania; Voisset, Michel; Vernant, Antoine-mathieu; Bayon, Germain; Cauquil, Eric; Adamy, J.; Colliat, J. L.; Drapeau, D.
Based on acquired geophysical, geological and geotechnical data and modeling, we suggest hydrate dissolution to cause sediment collapse and pockmark formation in the Niger delta. Very high-resolution bathymetry data acquired from the Niger delta reveal the morphology of pockmarks with different shapes and sizes going from a small ring depression surrounding an irregular floor to more typical pockmarks with uniform depression. Geophysical data, in situ piezocone measurements, piezometer measurements and sediment cores demonstrate the presence of a common internal architecture of the studied pockmarks: inner sediments rich in gas hydrates surrounded by overpressured sediments. The temperature, pressure and salinity conditions of the studied area have allowed...
Tipo: Text
Palavras-chave: Methane gas hydrate; Sea floor; Marine sediments; Pore pressure; Porous media; Continental margin; Clathrate hydrate; Fluid flow; Stability; Slope.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00012/12300/9092.pdf