Measurement preciseness analysis of stress-strain system at seismic frequencies

Precisely measuring the elastic parameters of porous sample with saturated fluids at the seismic frequencies is challengeable. Spencer (1981) first successfully managed the force-deformation method with strain amplitude less than 10^-6 and frequency below 100Hz in dry and water saturated rocks. However, the disadvantage of direct stress-strain method under small amplitude is an experimentally difficult, requiring considerable preciseness in sample preparation and data acquisition. The most important systematic error identified in the stress-strain method is the effect of the contact surface at the sample-gauge and the interface between the sample and standard (Liu et al.,1983; Li, 2015). We qualitatively analyze the contact surface and interface effects on the measurement preciseness of stress-strain method in this paper.