How does deformation change the land above a subduction zone?
Recent data from the Pacific Northwest and other subduction zones show that there are 3 distinct areas of movement above a subduction zone: 1) constant movement above the locked leading edge, 2) see-saw pattern of back-&-forth movement above a zone that alternately locks then slips in a process called episodic tremor and slip , and 3) no movement far inland above the deeper part of the diving oceanic plate.
- Subduction zones have variable stress
- Three graphs represent compressional stress in different subduction regions
- Near-trench overlying plate shows steady compression and deformation
- The transition zone graph has a sawtooth pattern indicating periodic slip
- Flat pattern inland indicates the subducting plate is not locked