Today, let us deviate just a bit from subject matter which is purely 'Cascadian' in nature. An August 26, 2016 article in The Lewiston Tribune, linked here, is titled 'Recent earthquakes have Northwest seismologists talking.' The article starts with these words: "The earthquakes in Italy and Myanmar are a grim reminder of the seismic dangers Puget Sounders face."
The linked article notes that the recent earthquake in Italy "is comparable to a rupture of a shallow fault, like the Seattle Fault, which cuts across Bremerton through South Seattle to the Cascade foothills." The article then declares that there are differences between what is happening, geologically, in Italy and what is happening in the Cascadia region. It states that in Italy, "the tectonic plates are spreading away from one another," while in the Cascadia region, "we're basically being squeezed from Oregon to Canada, which creates thrust faults."
Let us look, for a moment, at what is actually happening, geologically, in Italy in the region in which the recent earthquake occurred. There exists a deep fault in central Italy which extends from the city of Anzio (which is south of Rome) in a northeasterly direction all the way to the city of Ancona, on the east coast of Italy. These two cities (Anzio, south of Rome, on the coast, and Ancona, in a northerly direction on the opposite coast) are shown on the map linked here. This deep fault between these two coastal cities is along what is commonly called the Ancona-Anzio Line. A book titled 'Earthquakes: Observation, Theory and Interpretation' [Kanamori and Boschi, Paperback Edition, 1986, page 525] indicates that in the region of this line, there is a release of seismic energy which is greater than that in all the surrounding parts of Italy. It also indicates that subcrustal quakes occur along this line.
It should be noted that the recent Italian earthquake was located "in the region" of the Ancona-Anzio Line, as can be seen on the maps linked here and here, and in a map within the article linked here.
The 'Earthquakes...' book referenced further above [on pages 525 and 527] indicates that the cause of earthquakes in the region of the Ancona-Anzio Line is because of the difference in behavior of the tectonic plates on each side of the line. A map on page 524 of the referenced book indicates that the Ancona-Anzio Line is the point at which the southern portion of Italy is underthrusting the northern portion. Once again, this compression and thrusting is similar to what is occurring along the coastal areas of Cascadia. A USGS page linked here states: "Northward motion of Oregon block squeezes western Washington against Canadian Coast Mountains restraining bend, causing N-S compression, uplift, thrust faulting, and earthquakes." But, there is more for us to consider in the story about what is happening with Italy.
The 'Earthquakes...' book referred further above, on the map found on page 524, shows that things are a bit more complicated in Italy along this Ancona-Anzio Line. It indicates that the southern portion of Italy, below the cross-country fault line, is slowly rotating counterclockwise, in relation to the northern portion of Italy. This would indicate that any spreading of tectonic plates from one another, as mentioned in The Lewiston Tribune article, would tend to exist on the western side of Italy, near Rome. Could this spreading or weakening of the landmass in the region near Rome be part of the reason that Colli Albani appears to be awakening and possibly preparing for another one of its very explosive, eruptive cycles? Information about Colli Albani and its eruptive cycles can be found in the following four links: (1) (2) (3) (4)
On the map linked here, note the locations of Roma (Rome) and Latina in relation to the volcano at Albano (Vulcano Albano). Note also the location of Anzio on the Google map, linked here. It can clearly be seen that the volcano at Albano (marked with the red marker in the Google map) is located on the spreading or weakening end of the Ancona-Anzio fault line. With recent movement taking place along the Ancona-Anzio Line in the central part of Italy, just how long could it truly be before the landmass at Albano is weakened enough to let the magma explosively break through, once again? Will it happen before or after Cascadia cuts loose with its devastating mega-quake?
For further reading:
Current Expectations for a Cascadia Mega-Quake
https://cascadian.neocities.org/cascadiaquake.htm
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