Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)

In this study one seismic section offshore Chiloé Island was analyzed to better define the seismic character of the hydrate-bearing sediments. The velocity analysis was used to estimate the gas-phase concentration and relate it to the geological features. The velocity model allowed us to recognize t...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Vargas-Cordero,Iván de la Cruz, Tinivella,Umberta, Villar-Muñoz,Lucía, Giustiniani,Michela
Lenguaje:	English
Publicado:	Servicio Nacional de Geología y Minería (SERNAGEOMIN) 2016
Materias:	AVO BSR BGR Seismic analysis Pre-stack depth migration Free gas Gas hydrates
Acceso en línea:	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-71062016000300002
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:scielo:S0718-71062016000300002
record_format	dspace
spelling	oai:scielo:S0718-710620160003000022016-11-09Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)Vargas-Cordero,Iván de la CruzTinivella,UmbertaVillar-Muñoz,LucíaGiustiniani,Michela AVO BSR BGR Seismic analysis Pre-stack depth migration Free gas Gas hydrates In this study one seismic section offshore Chiloé Island was analyzed to better define the seismic character of the hydrate-bearing sediments. The velocity analysis was used to estimate the gas-phase concentration and relate it to the geological features. The velocity model allowed us to recognize two important layers that characterize hydrate- and free gas-bearing sediments above and below the BSR respectively: one located above the BSR, characterized by high velocity (1,800-2,200 m/s) and a second one, below the BSR, characterized by low velocity (1,600-1,700 m/s). A weak reflector at about 100 m below the BSR marks the base of the second layer. AVO analysis and offset stack sections confirming that the reflector interpreted as BGR is related to free gas presence in the pore space. The velocity field is affected by lateral variation, showing maximum (above the BSR) and minimum (below the BSR) values in the sector. Here, the highest gas hydrate and free gas concentrations were calculated, obtaining 9.5% and 0.5% of total volume respectively. A variable BSR depth (from 300 to 600 mbsf) can be justified supposing a variable geothermal gradient (from 25 to 45 °C/km).info:eu-repo/semantics/openAccessServicio Nacional de Geología y Minería (SERNAGEOMIN)Andean geology v.43 n.3 20162016-09-01text/htmlhttp://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-71062016000300002en10.5027/andgeoV43n3-a02
institution	Scielo Chile
collection	Scielo Chile
language	English
topic	AVO BSR BGR Seismic analysis Pre-stack depth migration Free gas Gas hydrates
spellingShingle	AVO BSR BGR Seismic analysis Pre-stack depth migration Free gas Gas hydrates Vargas-Cordero,Iván de la Cruz Tinivella,Umberta Villar-Muñoz,Lucía Giustiniani,Michela Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)
description	In this study one seismic section offshore Chiloé Island was analyzed to better define the seismic character of the hydrate-bearing sediments. The velocity analysis was used to estimate the gas-phase concentration and relate it to the geological features. The velocity model allowed us to recognize two important layers that characterize hydrate- and free gas-bearing sediments above and below the BSR respectively: one located above the BSR, characterized by high velocity (1,800-2,200 m/s) and a second one, below the BSR, characterized by low velocity (1,600-1,700 m/s). A weak reflector at about 100 m below the BSR marks the base of the second layer. AVO analysis and offset stack sections confirming that the reflector interpreted as BGR is related to free gas presence in the pore space. The velocity field is affected by lateral variation, showing maximum (above the BSR) and minimum (below the BSR) values in the sector. Here, the highest gas hydrate and free gas concentrations were calculated, obtaining 9.5% and 0.5% of total volume respectively. A variable BSR depth (from 300 to 600 mbsf) can be justified supposing a variable geothermal gradient (from 25 to 45 °C/km).
author	Vargas-Cordero,Iván de la Cruz Tinivella,Umberta Villar-Muñoz,Lucía Giustiniani,Michela
author_facet	Vargas-Cordero,Iván de la Cruz Tinivella,Umberta Villar-Muñoz,Lucía Giustiniani,Michela
author_sort	Vargas-Cordero,Iván de la Cruz
title	Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)
title_short	Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)
title_full	Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)
title_fullStr	Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)
title_full_unstemmed	Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)
title_sort	gas hydrate and free gas estimation from seismic analysis offshore chiloé island (chile)
publisher	Servicio Nacional de Geología y Minería (SERNAGEOMIN)
publishDate	2016
url	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-71062016000300002
work_keys_str_mv	AT vargascorderoivandelacruz gashydrateandfreegasestimationfromseismicanalysisoffshorechiloeislandchile AT tinivellaumberta gashydrateandfreegasestimationfromseismicanalysisoffshorechiloeislandchile AT villarmunozlucia gashydrateandfreegasestimationfromseismicanalysisoffshorechiloeislandchile AT giustinianimichela gashydrateandfreegasestimationfromseismicanalysisoffshorechiloeislandchile
_version_	1714205853518659584

Gas hydrate and free gas estimation from seismic analysis offshore Chiloé island (Chile)

Ejemplares similares