Petro-mineralogical controls on coda attenuation in volcanic rock samples

SUMMARY Seismic attenuation measurements, especially those obtained from coda decay analysis, are becoming a key data source for the characterization of heterogeneous Earth due to their sensitivity small-scale heterogeneities. However, relation between scattering measured waves and physical rock properties is still unclear. The goal this study identify main petrophysical mineralogical factors controlling in volcanic rocks at laboratory scale, as necessary step before modelling seismic real media. Coda wave was estimated ultrasonic S-wave waveforms. To quantify heterogeneity link them with parameter, we performed several categorizations pore grain systems samples. Considering that samples can be modelled using framework propagation random media, statistical analysis shear velocity fluctuations performed: gives correlation lengths ranging 0.09 1.20 mm, which represents length scale individual evaluation space mineral content revealed pores (characterized by large vesicles) have bigger effect than grains on level. We developed where intrinsic host drive correlating petro-mineralogical characteristics image processing frequencies. There conclusive evidence porosity alone not primary controller attenuation: it also changed alteration level (i.e. oxidation, coating vesicles, secondary minerals) size pores. Among all parameters analysed, appears topology contributor