Probing rock rupture with naturally occurring nuclide signals

Area of Science:

• Geochemistry
• Geophysics
• Rock Mechanics

Background:

• Naturally occurring nuclides (radon, helium, argon, thoron) release geochemical signals before rock failure.
• These signals, observed for decades, have potential for predicting earthquakes, volcanic eruptions, and landslides but remain underutilized.
• Current methods lack effective interpretation for geohazard prediction.

Purpose of the Study:

• To develop a novel decomposition and interpretation method for geochemical nuclide signals.
• To establish a universal paradigm for nuclide signal evolution linked to rock rupture.
• To create a diagnostic theory for rock rupture assessment using nuclide signals.

Main Methods:

• Analyzing time series of nuclide signals from laboratory rock failure experiments and field slope deformation.
• Developing a decomposition method to identify transient pulses and equilibrium fluctuations in nuclide signals.
• Employing analytical derivation and pore-scale simulations to link signals to rupture parameters (area, crack aperture).

Main Results:

• Identified a universal paradigm unit of nuclide signal evolution characterized by transient pulses and equilibrium fluctuations.
• Established constitutive equations connecting nuclide signals to key rock rupture structural parameters.
• Successfully applied the diagnostic theory to track rock failures at laboratory and field scales.

Conclusions:

• The developed nuclide signal decomposition and rupturing model unifies micro- and macro-scale rock failure signals.
• This integration provides a foundation for mesoscopic rock damage assessment.
• The findings pave the way for enhanced early warning systems for geohazards induced by rock ruptures.