Wave Propagation In A Fluid-Filled Fracture-An Experimental Study
A laboratory experimental study has been carried out to investigate the mode trapping characteristics of a fluid-filled fracture between two elastic solids. Using a small circular cylindrical receiver of 2.7 mm diameter, we were able to measure the wave motion directly inside a 2.8 mm thick fractu...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Technical Report |
| Published: |
Massachusetts Institute of Technology. Earth Resources Laboratory
2012
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| Online Access: | http://hdl.handle.net/1721.1/75114 |
| _version_ | 1826210569911271424 |
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| author | Tang, X. M. Cheng, C. H. |
| author2 | Massachusetts Institute of Technology. Earth Resources Laboratory |
| author_facet | Massachusetts Institute of Technology. Earth Resources Laboratory Tang, X. M. Cheng, C. H. |
| author_sort | Tang, X. M. |
| collection | MIT |
| description | A laboratory experimental study has been carried out to investigate the mode trapping
characteristics of a fluid-filled fracture between two elastic solids. Using a small circular cylindrical receiver of 2.7 mm diameter, we were able to measure the wave motion
directly inside a 2.8 mm thick fracture and to obtain array data for the propagating
waves. The data was processed using Prony's method to give velocity of the wave
modes as a function of frequency. The experimental results agree with the theoretical
predictions quite well. Specifically, in a "hard" (aluminum) fracture where the shear
velocity of the solid is greater than the fluid velocity, four normal modes were detected
in the frequency range up to 2.4 MHz. Whereas in a "soft" (lucite) fracture where the
shear velocity is smaller than the fluid velocity, four leaky-P modes were detected in the same frequency range. In both cases, a fundamental mode analogous to Stoneley waves
in a borehole was detected. In particular, the velocity of this mode approaches zero in
the low frequency limit, as indicated by the theory and confirmed by the experiment
in a low frequency range down to 25 kHz. |
| first_indexed | 2024-09-23T14:51:43Z |
| format | Technical Report |
| id | mit-1721.1/75114 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T14:51:43Z |
| publishDate | 2012 |
| publisher | Massachusetts Institute of Technology. Earth Resources Laboratory |
| record_format | dspace |
| spelling | mit-1721.1/751142019-04-11T01:22:19Z Wave Propagation In A Fluid-Filled Fracture-An Experimental Study Tang, X. M. Cheng, C. H. Massachusetts Institute of Technology. Earth Resources Laboratory Tang, X. M. Cheng, C. H. A laboratory experimental study has been carried out to investigate the mode trapping characteristics of a fluid-filled fracture between two elastic solids. Using a small circular cylindrical receiver of 2.7 mm diameter, we were able to measure the wave motion directly inside a 2.8 mm thick fracture and to obtain array data for the propagating waves. The data was processed using Prony's method to give velocity of the wave modes as a function of frequency. The experimental results agree with the theoretical predictions quite well. Specifically, in a "hard" (aluminum) fracture where the shear velocity of the solid is greater than the fluid velocity, four normal modes were detected in the frequency range up to 2.4 MHz. Whereas in a "soft" (lucite) fracture where the shear velocity is smaller than the fluid velocity, four leaky-P modes were detected in the same frequency range. In both cases, a fundamental mode analogous to Stoneley waves in a borehole was detected. In particular, the velocity of this mode approaches zero in the low frequency limit, as indicated by the theory and confirmed by the experiment in a low frequency range down to 25 kHz. Massachusetts Institute of Technology. Full Waveform Acoustic Logging Consortium United States. Dept. of Energy (Grant DE-FG02-86ERI3636) 2012-11-29T20:44:45Z 2012-11-29T20:44:45Z 1989 Technical Report http://hdl.handle.net/1721.1/75114 Earth Resources Laboratory Industry Consortia Annual Report;1989-04 application/pdf Massachusetts Institute of Technology. Earth Resources Laboratory |
| spellingShingle | Tang, X. M. Cheng, C. H. Wave Propagation In A Fluid-Filled Fracture-An Experimental Study |
| title | Wave Propagation In A Fluid-Filled Fracture-An Experimental Study |
| title_full | Wave Propagation In A Fluid-Filled Fracture-An Experimental Study |
| title_fullStr | Wave Propagation In A Fluid-Filled Fracture-An Experimental Study |
| title_full_unstemmed | Wave Propagation In A Fluid-Filled Fracture-An Experimental Study |
| title_short | Wave Propagation In A Fluid-Filled Fracture-An Experimental Study |
| title_sort | wave propagation in a fluid filled fracture an experimental study |
| url | http://hdl.handle.net/1721.1/75114 |
| work_keys_str_mv | AT tangxm wavepropagationinafluidfilledfractureanexperimentalstudy AT chengch wavepropagationinafluidfilledfractureanexperimentalstudy |