Publication Date:
2022-12-06
Description:
Pore space controls the mechanical and transport properties of rocks. At the laboratory scale, seismic modeling is usually performed in relatively homogeneous settings, and the influence of the pore space on the recorded wavefields is determined by rock‐fluid interactions. Understanding this influence in dry rocks is instrumental for assessing the impact of pore topology on waves propagating in heterogeneous environments, such as volcanoes. Here, we simulated the propagation of shear waves as a function of pore space parameters in computational models built as proxies for volcanic rocks. The spectral‐element simulations provide results comparable with ultrasonic experiments, and the outcome shows that the size, shape, volume, and location of pores impact amplitudes and phases. These variations intensify in waveform coda after multiple scattering. Our results confirm that pore topology is one of the primary regulators of the propagation of elastic waves in dry rocks regardless of porosity.
Description:
Plain Language Summary:
Pores control the non‐elastic behavior and, in general, the petrophysical and mechanical properties of rocks. Such properties are essential to assess potential resources such as aquifers and reservoirs or hazards posed by earthquakes, volcanoes, and constructions. The factors controlling the elasticity of rocks are texture, pore space and the fluids filling the pores. While volcanoes represent a key target for rock characterization, measuring and modeling these factors in volcanic rocks remains challenging due to their intrinsic heterogeneities. In this study, we analyzed how pore space parameters influence the overall elastic properties of rocks by changing one parameter at a time. We created synthetic samples and performed computational simulations that show the individual contribution of the amount, size, location, and shape on waveform phases and amplitudes. The findings demonstrate that we can constrain the pore space in heterogeneous rocks in simple but realistic scenarios. Our results are the first step to provide computationaly‐driven forward models of seismic signals in heterogeneous volcanic media, necessary to predict the responses of volcanic rocks to stress.
Description:
Key Points:
Computational modeling quantifies the influence of pore space topology on S‐wave propagation in volcanic rocks.
Amount, size and location of pores impact ultrasonic wave propagation in dry rocks independently of porosity.
Path effects dominate the waveforms and depend on the location of the pores.
Description:
https://doi.org/10.17632/b5p54xtvv9.3
Keywords:
ddc:550.78
;
volcanic rocks
;
pore space topology
;
S-wave propagation
;
computational modeling
Language:
English
Type:
doc-type:article
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