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1D Electromagnetic (EM) Response Explorer

Qualitative Time Domain (TEM) and Frequency Domain (FDEM) trends over a two-layer Earth

Conductive (Low ρ)
Resistive (High ρ)
Teaching proxy: The curves use skin-depth weighting and half-space decay approximations, not a full Maxwell-equation layered-earth solver. Use them to study trends, not to predict instrument voltages or inversion-ready apparent resistivity.

Earth Model Controls

Layer 1 Resistivity (ρ₁) 10 Ω·m

Log scale: 1 to 1000 Ω·m

Layer 1 Thickness (h₁) 50 m
Layer 2 Resistivity (ρ₂) 100 Ω·m

Log scale: 1 to 1000 Ω·m

Simulation Controls

FDEM Settings

Survey Frequency (f) 1000 Hz

Adjust frequency to see Skin Depth change.

TEM Settings

Watch the diffusion of the EM field over time.

Subsurface Cross-Section

FDEM Skin Depth
TEM Smoke Ring

FDEM: Apparent Resistivity vs Frequency

TEM: Voltage Decay vs Time