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Title: Gas Hydrate Property Measurements in Porous Sediments With Resonant Ultrasound Spectroscopy

Abstract

Resonant ultrasound spectra were collected on natural geological core samples containing known amounts of water while under pressure with methane gas and cooled to sub-ambient temperatures such that methane hydrate formed in the pore space. Strong resonance peaks were observed using either compressional or shear mode transducers but only when gas hydrates were present. By using deuterated methane gas to form gas hydrate in a core sample obtained from the Mallik 5L-38 gas hydrate research well, resonance peak amplitude was conclusively shown to correlate with gas hydrate saturation. A pore water freezing model was developed that utilizes the known pore size distribution in a sample and pore water chemistry to predict gas hydrate saturations as a function of pressure and temperature. The model showed good agreement with the experimental measurements and demonstrated that pore water chemistry is the most important factor controlling equilibrium gas hydrate saturations in these sediments when gas hydrates are formed artificially in laboratory pressure vessels. With further development, the resonant ultrasound technique can provide a rapid, non-destructive, and field portable means of measuring the equilibrium P-T properties and dissociation kinetics of gas hydrates in porous media, determining gas hydrate saturations, and may provide new insights intomore » the nature of gas hydrate formation mechanisms in geological materials.« less

Authors:
; ; ; ;  [1];
  1. (PNNL)
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
909467
Report Number(s):
PNNL-SA-46843
AB0565000; TRN: US200722%%1268
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Geophysical Research. Solid Earth, 112(B05202); Journal Volume: 112
Country of Publication:
United States
Language:
English
Subject:
03 NATURAL GAS; AMPLITUDES; DISSOCIATION; DISTRIBUTION; FREEZING; GAS HYDRATES; KINETICS; METHANE; PRESSURE VESSELS; RESONANCE; SATURATION; SEDIMENTS; SHEAR; SPECTRA; SPECTROSCOPY; TRANSDUCERS; WATER; WATER CHEMISTRY; gas hydrate; resonant ultrasound spectroscopy; clathrate

Citation Formats

McGrail, B. Peter, Ahmed, Salahuddin, Schaef, Herbert T., Owen, Antionette T., Martin, Paul, and Zhu, Tao. Gas Hydrate Property Measurements in Porous Sediments With Resonant Ultrasound Spectroscopy. United States: N. p., 2007. Web. doi:10.1029/2005JB004084.
McGrail, B. Peter, Ahmed, Salahuddin, Schaef, Herbert T., Owen, Antionette T., Martin, Paul, & Zhu, Tao. Gas Hydrate Property Measurements in Porous Sediments With Resonant Ultrasound Spectroscopy. United States. doi:10.1029/2005JB004084.
McGrail, B. Peter, Ahmed, Salahuddin, Schaef, Herbert T., Owen, Antionette T., Martin, Paul, and Zhu, Tao. Sat . "Gas Hydrate Property Measurements in Porous Sediments With Resonant Ultrasound Spectroscopy". United States. doi:10.1029/2005JB004084.
@article{osti_909467,
title = {Gas Hydrate Property Measurements in Porous Sediments With Resonant Ultrasound Spectroscopy},
author = {McGrail, B. Peter and Ahmed, Salahuddin and Schaef, Herbert T. and Owen, Antionette T. and Martin, Paul and Zhu, Tao},
abstractNote = {Resonant ultrasound spectra were collected on natural geological core samples containing known amounts of water while under pressure with methane gas and cooled to sub-ambient temperatures such that methane hydrate formed in the pore space. Strong resonance peaks were observed using either compressional or shear mode transducers but only when gas hydrates were present. By using deuterated methane gas to form gas hydrate in a core sample obtained from the Mallik 5L-38 gas hydrate research well, resonance peak amplitude was conclusively shown to correlate with gas hydrate saturation. A pore water freezing model was developed that utilizes the known pore size distribution in a sample and pore water chemistry to predict gas hydrate saturations as a function of pressure and temperature. The model showed good agreement with the experimental measurements and demonstrated that pore water chemistry is the most important factor controlling equilibrium gas hydrate saturations in these sediments when gas hydrates are formed artificially in laboratory pressure vessels. With further development, the resonant ultrasound technique can provide a rapid, non-destructive, and field portable means of measuring the equilibrium P-T properties and dissociation kinetics of gas hydrates in porous media, determining gas hydrate saturations, and may provide new insights into the nature of gas hydrate formation mechanisms in geological materials.},
doi = {10.1029/2005JB004084},
journal = {Journal of Geophysical Research. Solid Earth, 112(B05202)},
number = ,
volume = 112,
place = {United States},
year = {Sat May 05 00:00:00 EDT 2007},
month = {Sat May 05 00:00:00 EDT 2007}
}
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