Using 40 mechanism solutions of earthquake focus and 3 synthetic solutions of small earthquake, the crustal stress field in and around Gansu region is discussed.

We built a seismotectonic model for the west part of this zone from data of geological profiles, deep crust seismic detection and earthquake focal mechanisms in this paper.

Reservior earthquake focal mechanisms are nearly aligned with the regional tectonic strain field, and reservior earthquakes are indistinguishable from tectonic earthquakes elsewhere in the region.