Low Frequency Rock Physics Experimental Measurement System Modification And Testing

To summarize the elasticity law of reservoir rocks is a profound guide to the discovery of oil and gas reservoirs,the seismic petrophysical method is particularly important as a research tool to indicate oil and gas exploration and describe reservoir lithology by seismic propagation law.In order to obtain and study the rock elastic parameters under different pressure,temperature and porosity conditions,it is necessary to be able to simulate the reservoir environment and accurately obtain the elastic parameters of reservoir rocks in the laboratory in addition to the limited field seismic data,so as to build a model to interpret them according to the petrophysical laws.Experimental petrophysics was born.Through decades of development,there have been numerous experimental petrophysical devices at different frequencies.A large amount of experimental data shows that there is a large difference between the reservoir elastic parameters obtained at ultrasonic and seismic frequency bands,and this dispersion phenomenon has become a hot topic of research.Therefore,it is especially necessary to improve the laboratory rock physics experimental device in a single frequency band into a broadband experimental device.Firstly,the existing ultrasonic petrophysical experimental device is improved to improve the accuracy of data acquisition and experimental efficiency,and the pressure control system,fluid saturation and repulsion control system are optimized;the temperature control system is added to realize the reservoir temperature simulation.The calibration and adjustment of the improved petrophysical experimental device were carried out to determine the accuracy and reliability of its acquisition of the demonstrated elastic parameters.Secondly,a low-frequency rock physics experiment device in the seismic band is added to the original ultrasonic rock physics experiment device,and its reliability and accuracy are verified through calibration and adjustment,so as to realize cross-frequency rock physics experiments from low to high frequency.Finally,the cross-frequency band and high and low frequency synergistic petrophysical experiments are realized by this device,and the differences in the observed elastic parameters brought by the reservoir rocks are studied and explained by the low-frequency seismic,ultrasonic experiments and simultaneous low-frequency seismic and ultrasonic experiments.