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2019-04-22, M6.1, Philippines
On the 22nd April 2019 an earthquake with magnitude 6.1 occurred at 09:11:11 UTC (17:11 local time) in Northern Philippines. The earthquake was at a depth of 20km and centered near the town of Castillejos in Zambales Province, west of Manila, the capital city. It has been reported that at least 11 people died. Strong earthquakes happen regularly in this region that are caused by the colliding tectonic plates -the Philippine Sea plate is bordered by the larger Pacific and Eurasia plates and the smaller Sunda plate.
Another earthquake occurred on the 23rd April at 05:37:52 (UTC) (1.37pm local time) measuring M6.4, with the epicentre at San Julian in eastern Samar. The US Geological Survey (USGS) said the quake measured magnitude 6.4 and there were no immediate reports of casualties or damage.
The earthquake was recorded at seismic stations worldwide, including stations of the Irish National Seismic Network (INSN), see seismic waveforms below (select figure to enlarge).
2018-11-30, M7.0, Alaska
An earthquake of magnitude 7.0 occurred in Southern Alaska, on the 30th November 2018 at 8:29 a.m. local time (17:29:28 UTC). The quake was centred about 11km north of Anchorage, the largest city in the state, according to the US Geological Survey (USGS). A series of aftershocks was recorded following the initial shock, which had a depth of 40.9km, the USGS said. Around 300,000 people live in Anchorage with 100,000 in the surrounding area. A tsunami warning issued for the Cook Inlet and southern Kenai Peninsula regions was later cancelled.
This earthquake occurred in the Alaska-Aleutian subduction zone, on a fault within the subducting Pacific slab.
The earthquake was recorded at seismic stations worldwide, including stations of the Irish National Seismic Network (INSN), see seismic waveforms below (select figure to enlarge).
2018-08-19, M8.2, Fiji Region
On the August 18, 2018, M 8.2 earthquake near Fiji occurred as the result of deep, normal faulting approximately 560 km beneath the South Pacific Ocean several hundred kilometers to the west of the Tonga Trench. There were no reports of casualties.
Earthquakes that have focal depths greater than 300 km are commonly termed “deep-focus†earthquakes. Deep-focus earthquakes cause less damage on the ground surface above their foci than similar-magnitude shallow-focus earthquakes, but large deep-focus earthquakes may be felt at great distance from their epicenters.
The earthquake was recorded at seismic stations worldwide, including stations of the Irish National Seismic Network (INSN), see seismic waveforms below (select figure to enlarge).
2018-08-05, M6.9, Indonesia
On 5th August, 2018, an earthquake measuring magnitude 6.9 occured in the Lombok Region, Indonesia at 18:46 local time. Latest media reports that at least 91 people have been killed, many more have been injured and thousands of houses have been destroyed or damaged throughout the region. It hit just a few days after shallow M6.4 on July 28 in which 17 people died.
The earthquake was recorded at seismic stations worldwide, including stations of the Irish National Seismic Network (INSN), see seismic waveforms below (select figure to enlarge).
2018-02-25, M7.5 Papua New Guinea
On 25th February, 2018, an earthquake measuring magnitude 7.5 occurred at 4a.m local time, in a rural, jungle area of the Southern Highlands in New Guinea, Papaua New Guinea. It wasn’t immediately clear if there was damage. No tsunami watches or warnings were issued because of the quake.
At the location of this earthquake, the Australia plate is converging with the Pacific plate and it occurred as the result of thrust faulting at shallow a depth. Thrust-faulting events of the size of the February 25th, 2018 earthquake are typically about 85×30 km (length x width).
The earthquake was recorded at seismic stations worldwide, including stations of the Irish National Seismic Network (INSN), see seismic waveforms below (select figure to enlarge).
2018-02-06, M6.4 Taiwan
On 6th February, 2018, an earthquake measuring magnitude 6.4 occurred northeast of Hualien, Taiwan. So far at least seven people have been killed and more than 250 injuries have been reported. Aftershocks continue to occur in Taiwan since the earthquake.
Taiwan lies in a region of complex tectonics near the intersection of three major tectonic plates – the Philippine Sea plate to the east and southeast, the Eurasia plate to the north and west, and the Sunda plate to the southwest. The February 6th 2018 earthquake is the largest in a sequence of events in the same region over the past several days. Because of its plate boundary location, Taiwan commonly experiences moderate-to-large earthquakes.
The earthquake was recorded at seismic stations worldwide, including stations of the Irish National Seismic Network (INSN), see seismic waveforms below (select figure to enlarge).
2018-01-23, M8.0 Gulf of Alaska
A major earthquake with magnitude 8.0 occurred in the Gulf of Alaska on the 23rd January 2018 at 09:31:41 UTC at a depth of about 25km. A tsunami warning was issued but has been cancelled. The Aleutian arc extends approximately 3,000 km from the Gulf of Alaska in the east to the Kamchatka Peninsula in the west. It marks the region where the Pacific plate subducts into the mantle beneath the North America plate. This subduction is responsible for the generation of the Aleutian Islands and the deep offshore Aleutian Trench. The Aleutian arc is a seismically active region, evidenced by the many moderate to large earthquakes occurring each year.
The earthquake was recorded at seismic stations worldwide, including stations of the Irish National Seismic Network (INSN), see seismic waveforms below (select figure to enlarge).
Further information is available from the following webpages:
EMSC: https://www.emsc-csem.org/Earthquake/earthquake.php?id=642932
GFZ: https://geofon.gfz-potsdam.de/eqinfo/event.php?id=gfz2018boxy
USGS: https://earthquake.usgs.gov/earthquakes/eventpage/us2000cmy3#origin
More information about the INSN is available via this link.
VAL - Kerry
IMAY - Mayo
