1881 Castle Hill earthquake
The 1881 Castle Hill earthquake occurred at approximately 7:35 am on 5 December 1881, with an epicentre located in the area around Torlesse Range in Castle Hill, around 20 kilometres from Cass. The [Seismic Seismic magnitude scales|magnitude scales|magnitude] of the earthquake is generally estimated to be around 6.0 at a depth of 12 km. Published reports claim it lasted for between 20 and 40 seconds, beginning with a jolt described as "sharp" and "distinct".
The earthquake was widely felt around the South Island, with reports as far south as Dunedin. Locally, the earthquake caused soil liquefaction. In the city of Christchurch, approximately 80 kilometres from the epicentre, it caused minor damage to brick buildings, including damage to some parts of the Christ Church Cathedral spire. In Lyttelton, the Timeball Station clock reportedly stopped at 7:36 am.
Earthquake
At approximately 7:35 am on 5 December 1881, the earthquake struck in the Castle Hill area, believed to have an epicentre in the Torlesse Range area around 20 kilometres from the settlement of Cass, and a depth of 12 km. The magnitude of the earthquake is widely estimated to have been between 6.0 and 6.2 and a maximum MM intensity of 8 at the epicenter.Anecdotal reports indicate a shaking that began as a "sharp" and "distinct" jolt, progressing to "undulating" movement, which lasted approximately 20–40 seconds and was felt across the South Island in various locations including Christchurch, Timaru, Dunedin, Ashburton, and Greymouth, among other places. In Oxford and Christchurch, the MM intensity was rated at between 6 and 7.
Aftershocks were reportedly felt that afternoon at around 5:00 pm and 7:30 pm. They continued in the days following, including on 6 December at both 2:10 am and at 5:00 am; the former was described as lasting for a "considerable duration" with a "rumbling" heard, while the latter was reported as a minor shake of "very slight character".