Sounds like a solid idea—acoustic signatures can pick up subtle shifts that the eye misses. The key will be to get a dense array of calibrated microphones and make sure you’re filtering out weather noise. Then you can generate a heat‑map of sound levels and compare it to your topo data. If you’re able to match a rise in ambient noise with a small elevation change, you’ll have a new layer of information. Just remember to keep your sync tight, or you’ll end up with ghost‑maps that look nice but mean nothing. Give it a go and let me know what you hear.