Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones
Autor(a) principal: | |
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Data de Publicação: | 2009 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Revista Brasileira de Geofísica (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-261X2009000100004 |
Resumo: | There are numerous efforts to obtain information about saturation and pressure changes due to reservoir production from time-lapse seismic data. In spite of some good examples existing on the literature, there are a lot of approximations behind those studies. Generally, it is assumed that the seismic properties are functions of saturation and differential pressure Pd (overburden minus fluid pressure). Actually, the stress that governs the seismic behavior is the effective stress Pef, which is not exactly equal to Pd. In fact it is equal to the overburden stress minus n times the fluid pressure. Such coefficient (n) is known as the effective stress coefficient. Sometimes, depending on the circumstances, it might be identified as the Biot-Willis coefficient taking into consideration the bulk modulus of the porous media. In this paper, laboratory results in a tentative to quantify the n values for Brazilian limestones and tight sands will be presented. It is important to point out, that is the first effort to perform this sort of measurements on Brazilian rocks. The results have shown that the mentioned approximations can introduce errors on pressure estimations from time-lapse data even for high porosity rocks. |
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Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstoneseffective pressureporepressureseismic velocitiesBiot-Willis coefficient4D seismicThere are numerous efforts to obtain information about saturation and pressure changes due to reservoir production from time-lapse seismic data. In spite of some good examples existing on the literature, there are a lot of approximations behind those studies. Generally, it is assumed that the seismic properties are functions of saturation and differential pressure Pd (overburden minus fluid pressure). Actually, the stress that governs the seismic behavior is the effective stress Pef, which is not exactly equal to Pd. In fact it is equal to the overburden stress minus n times the fluid pressure. Such coefficient (n) is known as the effective stress coefficient. Sometimes, depending on the circumstances, it might be identified as the Biot-Willis coefficient taking into consideration the bulk modulus of the porous media. In this paper, laboratory results in a tentative to quantify the n values for Brazilian limestones and tight sands will be presented. It is important to point out, that is the first effort to perform this sort of measurements on Brazilian rocks. The results have shown that the mentioned approximations can introduce errors on pressure estimations from time-lapse data even for high porosity rocks.Sociedade Brasileira de Geofísica2009-03-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-261X2009000100004Revista Brasileira de Geofísica v.27 n.1 2009reponame:Revista Brasileira de Geofísica (Online)instname:Sociedade Brasileira de Geofísica (SBG)instacron:SBG10.1590/S0102-261X2009000100004info:eu-repo/semantics/openAccessVasquez,Guilherme FernandesVargas Junior,Eurípedes do AmaralRibeiro,Cleide Jeane BacelarLeão,MarcosJusten,Julio Cesar Ramoseng2009-08-14T00:00:00Zoai:scielo:S0102-261X2009000100004Revistahttp://www.scielo.br/rbgONGhttps://old.scielo.br/oai/scielo-oai.php||sbgf@sbgf.org.br1809-45110102-261Xopendoar:2009-08-14T00:00Revista Brasileira de Geofísica (Online) - Sociedade Brasileira de Geofísica (SBG)false |
dc.title.none.fl_str_mv |
Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones |
title |
Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones |
spellingShingle |
Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones Vasquez,Guilherme Fernandes effective pressure porepressure seismic velocities Biot-Willis coefficient 4D seismic |
title_short |
Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones |
title_full |
Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones |
title_fullStr |
Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones |
title_full_unstemmed |
Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones |
title_sort |
Experimental determination of the effective pressure coefficients for Brazilian limestones and sandstones |
author |
Vasquez,Guilherme Fernandes |
author_facet |
Vasquez,Guilherme Fernandes Vargas Junior,Eurípedes do Amaral Ribeiro,Cleide Jeane Bacelar Leão,Marcos Justen,Julio Cesar Ramos |
author_role |
author |
author2 |
Vargas Junior,Eurípedes do Amaral Ribeiro,Cleide Jeane Bacelar Leão,Marcos Justen,Julio Cesar Ramos |
author2_role |
author author author author |
dc.contributor.author.fl_str_mv |
Vasquez,Guilherme Fernandes Vargas Junior,Eurípedes do Amaral Ribeiro,Cleide Jeane Bacelar Leão,Marcos Justen,Julio Cesar Ramos |
dc.subject.por.fl_str_mv |
effective pressure porepressure seismic velocities Biot-Willis coefficient 4D seismic |
topic |
effective pressure porepressure seismic velocities Biot-Willis coefficient 4D seismic |
description |
There are numerous efforts to obtain information about saturation and pressure changes due to reservoir production from time-lapse seismic data. In spite of some good examples existing on the literature, there are a lot of approximations behind those studies. Generally, it is assumed that the seismic properties are functions of saturation and differential pressure Pd (overburden minus fluid pressure). Actually, the stress that governs the seismic behavior is the effective stress Pef, which is not exactly equal to Pd. In fact it is equal to the overburden stress minus n times the fluid pressure. Such coefficient (n) is known as the effective stress coefficient. Sometimes, depending on the circumstances, it might be identified as the Biot-Willis coefficient taking into consideration the bulk modulus of the porous media. In this paper, laboratory results in a tentative to quantify the n values for Brazilian limestones and tight sands will be presented. It is important to point out, that is the first effort to perform this sort of measurements on Brazilian rocks. The results have shown that the mentioned approximations can introduce errors on pressure estimations from time-lapse data even for high porosity rocks. |
publishDate |
2009 |
dc.date.none.fl_str_mv |
2009-03-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-261X2009000100004 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-261X2009000100004 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0102-261X2009000100004 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Geofísica |
publisher.none.fl_str_mv |
Sociedade Brasileira de Geofísica |
dc.source.none.fl_str_mv |
Revista Brasileira de Geofísica v.27 n.1 2009 reponame:Revista Brasileira de Geofísica (Online) instname:Sociedade Brasileira de Geofísica (SBG) instacron:SBG |
instname_str |
Sociedade Brasileira de Geofísica (SBG) |
instacron_str |
SBG |
institution |
SBG |
reponame_str |
Revista Brasileira de Geofísica (Online) |
collection |
Revista Brasileira de Geofísica (Online) |
repository.name.fl_str_mv |
Revista Brasileira de Geofísica (Online) - Sociedade Brasileira de Geofísica (SBG) |
repository.mail.fl_str_mv |
||sbgf@sbgf.org.br |
_version_ |
1754820937267544064 |