The terrain northeast of the gorge was different from anything the eastern survey had crossed so far.
The compressed highland geology that had produced the gorge's stratified bands gave way on the second day of travel to something looser and deeper—ancient alluvial stone, layers of sediment compressed over geological time into a substrate that was neither the dense highland rock nor the layered gorge formation but something in between. The formation-layer passive read registered the difference immediately. Less dense than the gorge region. More conductive. Path-energy moved through this substrate faster, the way current moved faster through looser material, and the eastern ambient that had been concentrated in the gorge's compressed bands spread here into the wider rock.
