Monday, June 17, 2019

Thames (NZ): Thamesites feel earthquake 90 years ago

Creative Commons BY-NC-SA 3.0
Ninety years ago, 17 June 1929, Thamesites had a mid morning 'shake'. Reports soon circulated of an earthquake that was felt by many at 10.21a.m.

While at nearby Turua, there were reports of cars parked at a local garage, moving backwards and forwards four inches. Water in the drains also moved considerably.

While the reports said that earthquakes were uncommon at Thames, they could hardly be overlooked given the fault lines that surround the town, and across the Hauraki Plains.

The earthquake was felt all over New Zealand, the epicentre at the top of the South Island. The magnitude given was 7.3 or 7.8 on a different scale. Fifteen people were killed and one injured.

"The earthquake that struck Murchison on 17 June 1929 was felt all over New Zealand. Fortunately, the most intense shaking occurred in a mountainous and densely wooded area extending ~65 km north of Murchison that was sparsely populated. Casualties were therefore comparatively light and the damage was mostly confined to the surrounding landscape, where the shaking triggered extensive landslides over thousands of square kilometres, and surface faulting on the White Creek Fault in Buller Gorge."  Source: Geonet

Thames Fault Lines:
In 1897 the Thames Star covered a report by Mr James Park of the School of Mines concerning the three fault lines of interest. The Moanataiari Fault, the Collarbone Fault, and the Beach Slide Fault. Many disputed the Beach Slide Fault, but Park was adamant of its existence. He also went onto explain the importance of the faults in relation to the gold bearing reefs around the town.

Creative Commons BY-NC-SA 3.0 New Zealand
Indepth reports on the Goldfields of New Zealand feature in the Appendix to the Journals of the House of Representatives 1894 Session 1; and includes James Park's 1894 map: Geological Map of the Thames Goldfield 1894. Snip of map below, click the link for full file. The faults are marked as dash lines ------.

If you read any of the mining material and reports in the Thames Star there are frequent mentions of the different faults, especially the Moanataiari. In 1925 Mr J S Jobe, felt the Kuranui Mine on the south side of the fault was the best proposition for mining at the Thames.

Another report in 1929, mentions the Punga Flat Fault - entitled the Geology of Thames, A Volcanic Upheaval.

Many will remember the swarms of faults in the 1970s that led to the demise of the A Block at Thames High School. The iconic building was cracked during a series of earthquakes and later demolished. As was the old primer block at Thames South School.

ABOVE: 'A' Block, Thames High School - under demolition (query year).
Source: Thames Museum Photographic Collection