R4: Mineral sciences of the Earth surface

[R4-01] Understanding and application of spherical concretions: A new durable sealing material learnt from nature

「招待講演」

*Hidekazu Yoshida¹ (1. Nagoya University)

Keywords:Spherical concretion, Calciumu carbonate, Durable sealing material

Here, we introduce a more durable sealing method for concretion-forming resin developed by learning from natural calcite, CaCO3 spherical concretion formation. The method was tested by sealing flow paths next to a tunnel in an underground research laboratory at 350 m depth, in Hokkaido, Japan. The flow paths were initially sealed rapidly, then resealed after disturbance by repeated earthquakes just below the underground research laboratory at depths of 2–7 km and maximum magnitude Mw 5.4. The treated rock mass rapidly recovered its very low natural permeability, demonstrating robust self-sealing and healing.