Mike Turnbull Barambah 2025-08-15
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On 2025-08-15 at 23:49 UTC a magnitude ML5.6 earthquake occurred in the Barambah local municipality area, about 16 km south-east of the township of Goomeri in SE Queensland (See Figure 1). The shaking from this earthquake was felt strongly (MM IV) in the southern suburbs of Ipswich and very strongly (MM VI) in Noosa.
In Figure 1 the main earthquake location is shown with an orange circular marker, the aftershocks as smaller yellow markers, and historical earthquaks as red or violet markers.
It can be seen that the 2025-08-15 23:49 UTC event and its associated aftershocks are occurring in a localised area where there have been no recorded recent earthquakes since June 2024; and, previous to that, May 2019 and August 2017.
Initially detection of aftershocks relied on data from GA stations EIDS (Eidsvold, 150 km away) and BRS (Mt Nebo, NW of Brisbane, 135 km away), and ANU Seismometers in Schools station AUBSH (Beewah State High School, 100 km away). During this period only four aftershocks werer detected and located, ranging in magnitude from ML 0.6 to ML 1.0.
By 2025-08-27 Geoscience Australia staff had deployed six temporary monitoring stations in the immediate area of the initial event: stations KKV1, KKVN2, KKVN3, KKVN4, KKVN5, AND KKVN6. This allowed aftershocks of much smaller magnitudes to be detected and located, and those events are mapped in Figure 1.
The aftershock station deployment has enabled the calculation of well defined locations (for example, within error margins of 6 to 8 km for events of magnitude ML -0.3), and it seems that these events are occurring at a depth of from 10 to 15 km.
Using data from the aftershock station deployment a closely spaced group of aftershocks is forming about 5 km north-east of the location obtained for the initial earthquake before the aftershock monitoring deployment, with sporadic aftershock events occurring to the west and south at a distance of about 5 to 8 km (See Figure 2).
There are currently two outliers: one about 30 km to the north-east of the main event, and another about 35 km to the north-west; and these may or may not be considered as an aftershock. This consideration may be clarified as more aftershocks are observed over the next month and a better picture of the aftershock distribution is seen.
It is likely that the more precise location of the main event is within the closely grouped aftershocks to the north-east rather than where it is shown in Figure 2.
Although initially the aftershock observations seemed to be conforming with a SW to NE lineation suggesting a possible fault line, temporal development of the aftershocks are starting to contradict this observation.
The aftershocks are occurring with considerable time spacing between successive events, sometimes with two or three days between events. The aftershocks are also of relatively low magnitudes (ML 1.8 to ML -0.8) (See Figure 3). This presentation is very different to that of the aftershock cum reactivation series associated with the Whitsunday Passage ML 5.8 event in 2016, and also with that of the 2015 Mt Perry ML 5.0, where in the few weeks following the main shock several aftershocks per day were being recorded.
I will update these notes and the figure images on a regulat basis as I detect and analyse future aftershock events; so, I recommend interested parties to visit this site every few days or if you want to keep informed of the events as they occur.
Although, at the start of this aftershock sequence, the author speculated that the small earthquake events being recorded may not be aftershocks at all but the normal background seismicity of the local area, it is clear from the close grouping of the majority of small events depicted in Figure 2 that what we are observing is not consistent with that hypothesis. The current observation is consistent with the group of earthquake events about 5 km to the north of the indicated main event location being genuine aftershock events.
A full cataloge of earthquakes that I have located since 2004 is available online.