A quiet Alaska fault is missing the fluids scientists expected – and it’s changing what we know about earthquake zones

Large earthquakes have been common along the Alaska-Aleutian subduction zone, except at the Shumagin Gap. Yinchu Li

Not all earthquake faults behave the same. Some stick and snap, causing earthquakes. Others move slowly over time.

For years, the leading explanation for slow-moving faults has been that high-pressure fluids along the fault lubricate it, allowing the slabs to slide steadily rather than building up stress until that stress is eventually released in a large, destructive earthquake.