Time-lapse sonic logs reveal patchy CO2 saturation in-situ

Based on time-lapse sonic and neutron porosity logs from the Nagaoka CO2 sequestration experiment, a P-wave velocity-saturation relation at reservoir depth is retrieved. It does not coincide with either of the end-member models of uniform and patchy saturation but falls in between even if realistic...

Full description

Bibliographic Details
Main Authors: Caspari, Eva, Müller, T., Gurevich, Boris
Format: Journal Article
Published: American Geophysical Union 2011
Online Access:http://hdl.handle.net/20.500.11937/21086
_version_ 1848750492337831936
author Caspari, Eva
Müller, T.
Gurevich, Boris
author_facet Caspari, Eva
Müller, T.
Gurevich, Boris
author_sort Caspari, Eva
building Curtin Institutional Repository
collection Online Access
description Based on time-lapse sonic and neutron porosity logs from the Nagaoka CO2 sequestration experiment, a P-wave velocity-saturation relation at reservoir depth is retrieved. It does not coincide with either of the end-member models of uniform and patchy saturation but falls in between even if realistic error estimates for the host rock properties are considered. Assuming a random distribution of CO2 patches it is shown that the mechanism of wave-induced flow can be evoked to explain this velocity-saturation relation. Characteristic CO2 patch size estimates range from 1 to 5 mm. Such mesoscopic heterogeneity can be responsible for attenuation and dispersion in the well logging frequency band.
first_indexed 2025-11-14T07:37:41Z
format Journal Article
id curtin-20.500.11937-21086
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T07:37:41Z
publishDate 2011
publisher American Geophysical Union
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-210862017-09-13T16:03:34Z Time-lapse sonic logs reveal patchy CO2 saturation in-situ Caspari, Eva Müller, T. Gurevich, Boris Based on time-lapse sonic and neutron porosity logs from the Nagaoka CO2 sequestration experiment, a P-wave velocity-saturation relation at reservoir depth is retrieved. It does not coincide with either of the end-member models of uniform and patchy saturation but falls in between even if realistic error estimates for the host rock properties are considered. Assuming a random distribution of CO2 patches it is shown that the mechanism of wave-induced flow can be evoked to explain this velocity-saturation relation. Characteristic CO2 patch size estimates range from 1 to 5 mm. Such mesoscopic heterogeneity can be responsible for attenuation and dispersion in the well logging frequency band. 2011 Journal Article http://hdl.handle.net/20.500.11937/21086 10.1029/2011GL046959 American Geophysical Union fulltext
spellingShingle Caspari, Eva
Müller, T.
Gurevich, Boris
Time-lapse sonic logs reveal patchy CO2 saturation in-situ
title Time-lapse sonic logs reveal patchy CO2 saturation in-situ
title_full Time-lapse sonic logs reveal patchy CO2 saturation in-situ
title_fullStr Time-lapse sonic logs reveal patchy CO2 saturation in-situ
title_full_unstemmed Time-lapse sonic logs reveal patchy CO2 saturation in-situ
title_short Time-lapse sonic logs reveal patchy CO2 saturation in-situ
title_sort time-lapse sonic logs reveal patchy co2 saturation in-situ
url http://hdl.handle.net/20.500.11937/21086