Anisotropy of laser-induced electro-response in shale: Modelling and experimental validation

• A novel LIER model integrates laser-thermal effects, residual polarization fields, and thermionic emission to characterize shale anisotropy. • For out-of-plane anisotropy, the product of LIER parameters follows cubic/impulse functions under continuous laser and exponential under pulsed laser, with a threshold angle. • Tangential LIER measurements on cylindrical cores effectively separate bias voltage and laser power effects, enhancing model applicability. • LIER demonstrates potential as a real-time monitoring tool for shale anisotropy during laser drilling operations.