12/17/2023 0 Comments Quake series best to worst![]() The quake occurred in what was a complex plate boundary zone, he said, of which the high-risk Alpine Fault was just one component. “In this case, the Pacific plate is moving southwest toward the Australian plate, and that creates compression and compressive stresses, which are relieved in reverse-type earthquakes like this one,” Townend said. This indicated compression between the Australian and Pacific tectonic plates that collide beneath New Zealand to create our famously shaky environment. Victoria University geophysicist Professor John Townend said it appeared the quake had come about through reverse-type faulting – where a block above a fault moved up relative to the block below it. While there were no known historical quakes in this area that measured above magnitude 5.0, nearby large faults were understood to have ruptured several times within the past 18,000 years. The epicentre was located about 70km southeast of the Alpine Fault – the sprawling system that marked the plate boundary in this part of the South Island. More were expected, GNS Science seismic duty officer Katie Jacobs told the Herald. The 9.14am jolt – earlier estimated at magnitude 6.4 and 6.2, but since revised to 6.0 - was centred about 45km north of Geraldine, at a relatively shallow depth of 11km.įelt by more than 14,000 people mostly in the South Island, the earthquake was followed by 31 aftershocks within two and a half hours – the largest of which measured 3.6. What was one of the largest earthquakes of 2023 struck in a seismically quiet area, near faults known to have produced only a handful of big shakes in the past 18,000 years. What was one of the largest earthquakes of 2023 struck in a seismically quiet area, near faults that’ve produced only a handful of big shakes in the last 18,000 years. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |