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Low-frequency Experiments on Tight Sandstone and Its Dispersion Characteristics in the Seismic Frequency Band
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 80th EAGE Conference and Exhibition 2018, Jun 2018, Volume 2018, p.1 - 5
Abstract
In recent years, the experimental and theoretical researches on seismic wave velocity dispersion and attenuation of reservoir rocks have become more and more important. In this paper, by using the low-frequency stress-strain measurement system, two tight quartz-sandstone cores of buried hill reservoirs were used to measure the elastic parameters of different frequency under the conditions of saturated water and oil, and then the rock physics experimental data in the seismic frequency band are obtained. The measured results show that: Under the condition of saturated water, there is a 4.3% velocity dispersion variation of P wave in the seismic frequency band of 1–100Hz. Under the condition of saturated white oil, the dispersion variation of the P and S-wave are larger than them of saturated water, and the dispersion variation has reached 8%. With the increase of effective pressure, the dispersion variation of seismic wave was decreased. Thus, the property of pore fluid is the main cause of the velocity dispersion, its variation and characteristic frequency are increased with the increase of fluid viscosity. Meanwhile, combined with the squirt-flow rock physics mechanism, the seismic dispersion regularity of the tight quartz-sandstone is built to improve reservoir and oil or gas prediction accuracy.