Large Australian Earthquake

[davenn]

Hi guys and gals

The Australian doesn't get too may quakes M5 and up. On average one every approx. 4-5 years
The latest occurred this morning, 04:14:02 EST, 21st May ( local time) recorded as a M 6.1 by
Geoscience Australia ( GA is the Australian Govt. Institute for monitoring such activity.. equiv of the USGS)

The even is located in the SW corner of the Northern Territory state and some 2250 km from my location

20 May 2016 @ 18:14:02 Lat -25.474, Long 129.780 and 9 km deep

location map shows it approx. 80 km west of the tourist town of Yulara near the rock formation of Uluru ( Ayers Rock) so far in the 12 hours following the event, there have been 16 aftershocks measuring between M 2.5 and M 3.8 recorded

the long period seismogram from my recorder ( this event was well recorded on all my sensors
long and short period ones

cheers
Dave

 

[Astronuc]

Interesting. http://earthquake.usgs.gov/earthquakes/eventpage/us10005iyk#general
USGS puts it at Mag 5.9, with aftershocks of 4.2 and 4.4

Location: Lat 25.534°S, Long 129.805°E
Depth: 10.0 km (6.2 mi)

• 329.0 km (204.4 mi) E of Warburton, Australia

• 460.0 km (285.8 mi) WSW of Alice Springs, Australia

• 1001.0 km (622.0 mi) ENE of Kalgoorlie, Australia

• 1091.0 km (677.9 mi) NW of Port Augusta West, Australia

• 1341.0 km (833.3 mi) NW of Adelaide, Australia

There is no summary for the region. I wonder if there is some elevation change out there.

 

[davenn]

Interesting. http://earthquake.usgs.gov/earthquakes/eventpage/us10005iyk#general
USGS puts it at Mag 5.9, with aftershocks of 4.2 and 4.4

yeah, I'm starting to have less and less trust in the USGS/NEIC for magnitude determinations of late
The magnitude estimates seem to be really screwball for events that are well outside their main monitoring regions

The M6.7 and 6.8 events in Ecuador last week are a prime example of complete inconsistence in their magnitude estimates
For places like Australia and New Zealand ( where there are excellent local organisations) I will always prefer to go with their
posted magnitudes as those local organisations have high densities of recording stations to draw data from.

Now, back to the Australian event and its aftershocks. Geoscience Australia has reported only one aftershock reaching or exceeding M4
and that was a M 4.1. Three other events reached M 3.8

Here's a list of aftershocks for the first 24 hours .. a reasonably active sequence

There is no summary for the region. I wonder if there is some elevation change out there.

It would be interesting to see if the main event caused any surface faulting. If there is any, it wouldn't be too difficult to see across the desert floor from a low level helicopter flight over the area.
The pic below is typical of the look of the region. This is Uluru ( Ayres Rock) and the quake was around 80km west of here

Dave
.

 

[fresh_42]

Potsdam lists it as 6.0.
http://geofon.gfz-potsdam.de/eqinfo/list.php?page=1 (page in english)

 

[Astronuc]

So, the earthquakes have been occurring in the Central Ranges region.
https://en.wikipedia.org/wiki/Central_Ranges

Information on the area is sparse - as is the population. I was wondering how the range(s) relate to the Petermann, Mann, Musgrave and McDonnell ranges.
https://en.wikipedia.org/wiki/Petermann_Ranges_(Australia)

Mt. Whinham is to the south, and Mt. Woodroffe to the southeast.

I'm guessing that the Musgrave range splits into the Mann and Petermann ranges as one goes NW. The earthquakes seem to be in a basin between Mann and Petermann ranges. What are the features east of the earthquakes? I can't find names on any map.