2025 Earthquakes

There have recently been a number of earthquakes happening around the world, an 8.8 magnitude one in Russia, which sent Tsunami waves as far away as Japan and New Zealand. Also, a 4.8 one in Wyalkatchem last Wednesday which was felt as far away as Kalgoorlie. Apparently, there have been 130 earthquakes clusters detected across the Wheatbelt since July last year!

This prompts us to remind you of the existence of the Geophysical Observatory that operated here in Mundaring from 1959 to 2000.

Image 1 Mundaring Geophysical Observatory on Hodgson Road, now Mundaring Weir Road. Image 2 Sign outside the Mundaring Geophysical Observatory.

In 1919 scientists travelled from America to find a suitable spot for a Magnetic Observatory. They settled on a site at Watheroo 225klms north of Perth. They were investigating the Earth’s magnetic field. In 1947 the Carnegie Institution gifted Watheroo Magnetic Observatory to the Australian Government and Australian staff were required to operate it. However, the site was isolated and living conditions were primitive and so staff were difficult to find and keep.

The Mundaring Geophysical Observatory replaced the Watheroo Magnetic Observatory on 18th March 1959. The main functions of the Observatory were the collection and distribution of basic data in disciplines of geomagnetism, seismology, and ionospheric physics, and the application of this data to investigate all local and regional phenomena. There were two installations – Gnangara and Mundaring. Gnangara became the magnetic recording station while Mundaring became the main office and the seismological and ionospheric recording station.

When the Observatory was closed many of the instruments were donated to Mundaring & Hills Historical Society. The instruments range from a 1905 magnetograph recorder, first used at the Magnetic Observatory established at Watheroo in 1919 by the Department of Terrestrial Magnetism, Carnegie Institute of Washington, to a Benioff Seismometer that was still used at the Observatory when it closed in 2000. They are also objects of some beauty.

Image 1 Magnetic Recorder. Image 2 Recorder from the old Mundaring Observatory.

Two of the biggest earthquakes that the observatory would have recorded was the Meckering 6.9 Earthquake in1968 and Cadoux's 6.1 in 1979. Below are some photographs of the Meckering earthquake.