Haiyuan Fault

[3][1] The Tianzhu seismic gap is a 260 km (160 mi) long, unruptured segment on the western end of the fault.

[1][3] At the western end of the 1920 earthquake surface rupture, and between the Tianzhu seismic gap (from 37.11° N, 103.68° E to 37.00° N, 104.15° E) lies a 30–40 km (19–25 mi) section of the fault that displays a phenomenon known as an aseismic creep at shallow depths.

[6] On October 20, 1990, a Mw  5.8 earthquake ruptured a small section of the fault with a maximum China seismic intensity of VIII.

No formal geological investigation was conducted although it is believed to have produced a surface rupture for several kilometers.

[11] An Mw  6.6 or Ms  6.9 earthquake struck Menyuan County in January 2022, causing little damage and few minor injuries.

[14] It generated a 22 km (14 mi) surface rupture along the Lenglongling segment of the Haiyuan Fault.

The surface rupture also crossed the tunnel of a high-speed railway linking Lanzhou to Ürümqi, causing severe damage to a bridge and the tracks.

Modelling of the earthquake suggest it had a maximum coseisic slip of around 3.5 m (11 ft) at a depth of 0–10 km (0.0–6.2 mi) along the rupture.

The major fault structures in the Tibetan Plateau , the Haiyuan Fault is located within the Eurasian Plate.