Análisis sísmico-acústico de alta resolución del gas somero en la Ría de Muros-Noia (NO España)
- J. Magariños-Álvarez
- S. Garc
- Federico Vilas Martín
ISSN: 1576-5172
Ano de publicación: 2001
Título do exemplar: XIV Congreso Nacional de Sedimentología, IV Congreso del Cretácico de España
Número: 3
Páxinas: 203-206
Tipo: Artigo
Outras publicacións en: Geotemas (Madrid)
Resumo
Analysis and interpretation of high-resolution seismic reflection and side-scan sonar records has been performed in order to detect shallow gas signatures in the Rfa de Muros-Noia (NW Spain). Four main types of gas accumulations have been distinguished: I) acoustic blanking s.s., with a flat top surface and kilometric extent, 2) acoustic curtains, with a convex top surface and less than a hundred meters of lateral extent, 3) acoustic columns, with an enhanced reflector at the top, and 4) acoustic turbidity. Mapping of these features reveals the presence of a large gas field where gas accumulates from the close seabed surface up to 8 m. Two gas escape features have been also recognised: I) acoustic plumes into the water column, rising up to 20 m above the seafloor, and 2) pockmarks on the present seabed, easily recognised as high reflectivity areas in the side-scan sonar records.