EGU22-10156, updated on 28 Mar 2022
https://doi.org/10.5194/egusphere-egu22-10156
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

New granular rock-analogue materials for simulation of multi-scale fault and fracture processes

Luigi Massaro1, Jürgen Adam1, Elham Jonade1, and Yasuhiro Yamada1,2
Luigi Massaro et al.
  • 1Royal Holloway, University of London, Department of Earth Sciences, United Kingdom of Great Britain – England, Scotland, Wales (luigi.massaro.2018@live.rhul.ac.uk)
  • 2Department of Earth Resources Engineering, Kyushu University, Fukuoka, Japan

Dynamically scaled experiments allow the direct comparison of geometrical, kinematical and mechanical processes between model and nature. The geometrical scaling factor defines the model resolution, which depends mainly on the density and cohesive strength ratios of model material and natural rocks. Granular materials such as quartz sands are ideal for the simulation of upper crustal deformation processes as a result of similar nonlinear deformation behaviour of granular flow and brittle rock deformation. We compared the geometrical scaling factor of common analogue materials applied in tectonic models and identified a gap in model resolution corresponding to the outcrop and structural scale (1–100 m).

In this study, we present a new granular rock-analogue material (GRAM) with a dynamic scaling suitable for the simulation of fault and fracture processes in analogue experiments. The proposed material is composed of silica sand and hemihydrate powder and is suitable to form cohesive aggregates capable of deforming by tensile and shear failure under variable stress conditions. Based on dynamical shear tests, GRAM is characterized by a similar stress-strain curve as dry silica sand, has a cohesive strength of 7.88 kPa and an average density of 1.36 g cm−3. The derived geometrical scaling factor is 1 cm in model = 10.65 m in nature. For a large-scale test, GRAM material was applied in strike-slip analogue experiments. Early results demonstrate the potential of GRAM to simulate fault and fracture processes, and their interaction in fault zones and damage zones during different stages of fault evolution in dynamically scaled analogue experiments.

How to cite: Massaro, L., Adam, J., Jonade, E., and Yamada, Y.: New granular rock-analogue materials for simulation of multi-scale fault and fracture processes, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10156, https://doi.org/10.5194/egusphere-egu22-10156, 2022.

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