July 13, 2019– Mary Greeley News – A shallow earthquake of magnitude 5 struck 21 miles north of Jijel, Algeria, near Mediterranean Sea at a depth of 10 km, according to the U.S. Geological Survey. An earthquake of this magnitude is moderate.
Location 37.132°N 5.775°E
Depth uncertainty ± 6.5 km
It struck at Jul 13, 2019 at 09:56:35 AM UTC. USGS reports that this quake event was manually reviewed, but not details were given.
On the USGS felt report 9 people reported this earthquake. EMSC had 4 felt reports.
Witness location : جيجل (Algeria) (45 km S from epicenter)
“it was a slight trembling… I felt it but my husband didnt..came to this website to confirm”
Witness location : Bejaïa (Algeria) (77 km SW from epicenter)
“Feel good in BEJAIA city”
Witness location : أميزور (Algeria) (101 km SW from epicenter)
“A very small shake الحمد لله”
The Mediterranean is ultimately prone to tectonic (and volcanic) activity as a result of the collision of the African plate into the western portion of the Eurasian plate. For the past 65 million years or so, this collision has proceeded, producing the Alps, which are still growing, and closing the Tethys Sea which once separated both continents.
Today, the Mediterranean Sea is the remnant of the Tethys and it too is shrinking as the African plate continues to drive north at about 2.5cm per year. The boundary between these plates is not clear cut however, and as a result, the Mediterranean region is criss-crossed with active fault-lines and it is these, along with plate movements, which create a complex tectonic setting and produce the region’s earthquake risk.
Significantly however, the tectonics of the region are not at all that like those in Indonesia or Japan. In the Pacific and Indian Oceans, the tectonic hazard results largely from subduction, where one plate is driven beneath another. Large earthquakes are common at subduction boundaries, and often result in massive displacement at the ocean bed which generates very large tsunamis.
Although there are areas of subduction in the Mediterranean, the scale is much smaller meaning less displacement and smaller tsunamis. Scientists have, in fact, suggested that the 1908 Sicily tsunami was not directly a result of displacement at all, but rather the result of an earthquake-generated landslide on the seabed.
Mary Greeley News
credit: In part with https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2009GL039135