News from the Geoblogosphere
New from Snet:
, a new tool to create lithological/sedimentological logs online..
Blog post recommendation
1931 Napier earthquake in New Zealand, a reshaping event
The 03/02/1931 Mw7.5+ Hawke’s Bay earthquake caused strong shaking and extensive damage in Napier, a city of the north-eastern coast of northern island of New Zealand. It is the deadliest quake in New Zealand (256).
Reported intensities for the 1931 Hawke's Bay earthquake, from GNS (http://www.geonet.org.nz/quakes/region/newzealand/2178228)
The earthquake led to reshaping the city of Napier: because of extensive destruction there. A decision was adopted to build modern, cheap and safe. The result is these “art deco” style buildings, without ornamentation or extraneous columns, contrasting with the ornate pediments of the old architecture. For further information on this architectural topic of Napier, check these links:
- - http://www.napier.govt.nz/napier/about/history/napier-earthquake-1931/
- - https://www.theguardian.com/cities/2016/apr/15/story-of-cities-napier-disaster-art-deco-renaissance
- - https://theculturetrip.com/pacific/new-zealand/articles/architecture-art-deco-and-earthquakes-in-napier/
Rebuilding Napier from the ground (credit http://www.napier.govt.nz/)
This concrete structure has been erected after the 1931 earthquake (Photograph: Tim Whittaker)
The dislocation at depth during the earthquake caused a permanent deformation of the ground surface which significantly reshaped the landscape. Hull (1990) indicates that a wide zone of uplift defined a NE-trending dome with a minimum length of 90 km and at least 17 km width, in agreement with the extension of aftershocks. A lagoon north of Napier was partly dried because of a 1m-uplift. South of Napier, the eastern edge of the uplifted ridge (west side) is steeper and steeper to the south and a complex surface faulting was mapped over 15 km, with maximum vertical separation of 5 m (west block upthrown) and horizontal separation of 2 m.
Map illustrating the vertical surface deformation after the 1931 Napier earthquake, with contours and labels for local measurements. Surface rupture (dislocation) appeared to the south, over around 15 km. Hatched line is railway. After Hull 1990. Further information on the 1931 earthquake:
- http://info.geonet.org.nz/display/quake/M+7.8,+Hawke's+Bay,+3+February+1931 - http://www.teara.govt.nz/en/historic-earthquakes/page-6
Reference Hull (1990). Tectonics of the 1931 Hawke's Bay earthquake, New Zealand Journal o/Geology and Geophysics. 1990. Vol. 33: 309-320, 1990)