Sonic and electrical properties of partially saturated tight-gas sands. Final report

Technical Report · Tue Mar 01 00:00:00 EST 1983

DOI:https://doi.org/10.2172/6350056· OSTI ID:6350056

Nur, A

This study was aimed at relating the seismic and the electrical properties of tight-gas rocks to their pore-space geometry, permeability, and level of water saturation. Here we report results of a laboratory experimental study of wave propagation in Cotton Valley and Spirit River Sandstones as a function of partial water saturation (SW) and wave frequency. We find that wave velocities and the velocity ratio are sensitive to the presence of gas. Furthermore, wave attenuation is sensitive to the amount of gas in the pore space. Ultrasonic measurements in tight-gas sands tend to yield higher velocity values, due to the inability of the pore fluid pressure to homogenize during the passage of waves. Laboratory measurements were made also of the complex electrical response of selected tight rocks, and compared with normal permeability Berea Sandstone. The results show that the dielectric property of tight-gas sands is very sensitive to partial water saturation, and may give not only insight into the nature of the pore space, but also provide a practical measure of S/sub w/ in situ. 35 figures, 2 tables.

• Research Organization: Stanford Univ., CA (USA). Dept. of Geophysics
• DOE Contract Number: AS19-81BC10498
• OSTI ID: 6350056
• Report Number(s): DOE/BC/10498-5; ON: DE83009472
• Resource Relation: Other Information: Portions are illegible in microfiche products. Original copy available until stock is exhausted
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
58 GEOSCIENCES
NATURAL GAS DEPOSITS
ACOUSTIC MEASUREMENTS
ELECTRICAL PROPERTIES
PERMEABILITY
POROSITY
ULTRASONIC TESTING
WATER SATURATION
SANDSTONES
BENCH-SCALE EXPERIMENTS
CORRELATIONS
EXPERIMENTAL DATA
ULTRASONIC WAVES
WAVE PROPAGATION
ACOUSTIC TESTING
DATA
GEOLOGIC DEPOSITS
INFORMATION
MATERIALS TESTING
MINERAL RESOURCES
NONDESTRUCTIVE TESTING
NUMERICAL DATA
PHYSICAL PROPERTIES
RESOURCES
ROCKS
SATURATION
SEDIMENTARY ROCKS
SOUND WAVES
TESTING
030200* - Natural Gas- Reserves
Geology
& Exploration
580203 - Geophysics- Geophysical Survey Methods- (1980-1989)