FWI¶
Full-waveform inversion end to end: constant- and variable-density acoustic and elastic Marmousi, multiscale and frequency-selection encoding, batched streamer windows, and a 3-D Overthrust volume.
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FWI · Acoustic · Marmousi
Load Marmousi from
sweep.datasets, build a 192×320 window, forward-model observed gathers, and invert the smooth start with Adam + MSE. Each phase is one cell. -
FWI · VRZ · Marmousi
Acoustic variable-density (VRZ) FWI on Marmousi — vector reflectivity from impedance, inverted with the
AcousticVRZequation. -
FWI · Elastic · Marmousi
Same skeleton, but the equation is
Elasticand the model is the(vp, vs, rho)triplet.vsandrhoare derived fromvpwith Poisson + Gardner relations so the example still runs with zero downloads. -
FWI · multiscale
Three-band frequency progression (3 → 6 → 12 Hz) of acoustic FWI on Marmousi 25 m. Each band feeds its final model into the next; loss drops monotonically across the chain and avoids cycle skipping.
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FWI · Frequency-selection encoding
A towed-streamer survey, 129 shots every 100 m, all in one forward: each shot radiates its own monochromatic frequency, the steady-window DFT separates them with zero crosstalk, and a coherence misfit cancels the wavelet. Multiscale 1.5–3 / 2.5–5 / 4–10 Hz, each band on its own grid and time step (100 / 50 / 25 m), in plain torch on Marmousi.
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FWI · Batched per-shot local windows
A fixed streamer makes every shot's model window the same width, so all the crops stack into one batched solver call and the overlapping windows scatter-add back onto the full model through autograd. Frequency continuation recovers Marmousi from a smooth start on one GPU.
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FWI · 3-D · Overthrust
Acoustic FWI on a 3-D Overthrust volume —
Acoustic3Dsolver onimpl='eager', chunked checkpointing for memory, depth/inline/crossline slices of the recoveredvpcube vs ground truth.