Where have aftershocks been occurring in the last week? This map shows seismicity since March 6 (red) with earlier aftershocks (gray). Mapped faults are in blue.
The central part of the M7.8 (~Gaziantep) is pretty quiet now, and Hatay has only moderate seismicity.
Aftershocks are concentrated along the northern part of the ruptures, especially on the eastern (~Malatya) and western (~Göksun) ends.
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The time series shows that, as expected, the aftershocks are slowly decreasing, with the largest events ~M5. Larger aftershocks are still possible but less likely every day.
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Remember that each step on the magnitude scale is a factor of 30x more energy - so compared to a M4, a M5 is 30x more powerful, and a M6 is 900x more powerful. These smaller aftershocks are much, much smaller than the main shocks and are normal after a big earthquake.
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Authors choose every word carefully so it says exactly what they mean; technical words have precise meanings, and each one may refer to a whole field knowledge.
Here is a brief summary in non-technical language about what this paper says:
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The title states that during the two Feb. 6 big earthquakes in Turkey, the fault rupture traveled at different speeds on different parts of the faults - sometimes "sub-shear" and sometimes "super-shear."
They are comparing the rupture speed to the speed of shear waves.
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At the western edge of the Mw7.8 Turkey-Syria earthquake there is a subduction zone: the Cyprus-Hatay Arc. This area was stressed by the earthquake, and has produced some aftershocks.
The Cyprus Arc is a subduction zone: the African plate is sinking beneath the Eurasian plate. Here, the rainbow lines show the depth to the main fault (the "megathrust") between the two plates.
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Seismicity recorded since Feb 6 shows several aftershocks along the eastern part of the arc.
So it seems that the stress from the earthquake sequence is indeed producing a response on this fault system.
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A couple hours ago, there was a M4.2 earthquake near Adana.
This is not a large event, but it was widely felt. Although there have been many aftershocks of this magnitude, this is the largest to occur so close to Adana.
At this point there is no way to know what will happen. The most likely scenario is that there will be a few more smaller events. There could be more similar-magnitude events (M4-5). It is possible, though not likely, that there could be a larger event.
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In the map above I've included a new fault map. These are based on the new AFEAD database. In my map all the faults are all drawn in the same color, but they do not all pose the same hazard.
But the reality is that "plate edges" are not so clearly defined. Zoom in on California, Iran, Turkey, Japan - and you will find many hundreds of faults that interact in complicated ways.
Although most moderate earthquakes are not a signal of future large events, some large earthquakes do have foreshocks. So it is good to pay attention to these events - they are telling us something about the faults in the area.
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The most likely scenario is that the area will experience aftershocks, getting smaller and less frequent over time.
However, with three events of similar magnitude already, more M4-5 events are possible.
There is also a small chance of a larger triggered event.
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