Earthquake Insights

Find our new posts at  https://earthquakeinsights.substack.com/ . Why the move? Substack offers better features - including the option to post high-resolution pdfs, which we hope to take advantage of soon.

About an hour ago, a M4.3 earthquake occurred in northeastern India, with shaking also felt in SE Nepal and NW Bangladesh. Although this area has various kinds of active tectonics, the earthquake occurred within the (relatively) stable Indian Plate.

In this op-ed for Anadolu Agency, I explain how the fact that we can’t measure the stress state on faults means that we can’t know when little earthquakes, which occur every day, will grow into big ones.  

Has there been more seismicity around the Black Sea since the Feb. 6 earthquakes? Answer: reported seismicity has been a little higher than usual, but that kind of variability is well within the range of normal and may partially due to network reporting.

  In 1985, an eruption at Nevado del Ruiz in Colombia triggered deadly mudflows - lahars - that killed more than 20,000 people. That volcano is showing signs of life once again.

I've spent a lot of time looking at earthquakes in Southeast Turkey, where the Feb. 6 Turkey-Syria earthquake sequence occurred. What about the rest of the country? This map shows all magnitude 3+ earthquakes (blue=before Feb. 6, red=after), active faults, and crustal motion recorded by GPS.

Today's M4.2 earthquake in Oklahoma is a reminder of the oil production in the area, which has caused a surge of seismicity - including a M5.7 in 2011 and a M5.8 in 2016.

Today's M6.3 earthquake off the west coast of Panama occurred at the junction of three plates: the Panama, Cocos, and Nazca Plates. The Cocos Plate subducts northeast below Panama; the Nazca Plate subducts east below South America.

A M4.5 earthquake south of San Francisco, near Hollister, caused intensity 4-5 shaking right around the epicenter, with intensity 2-3 more broadly across the region.

It has been nearly two months since the Feb 6 Turkey-Syria earthquakes. What do aftershocks look like now? This map shows recorded seismicity above M2.5. Red = events since April 1.

A M6.1 earthquake just occurred near the west coast of Sumatra, Indonesia. At 85 km depth, this event has likely produced fairly wide-spread, but low intensity shaking.

A M6.5 earthquake occurred below the eastern coast of Russia's Kamchatka peninsula today. More than 200k people likely felt strong shaking, and some damage to infrastructure is expected.

I have heard from a number of people in Lebanon and Syria that they were feeling more shaking than usual... but no earthquakes were showing up in my usual earthquake catalogs. So I decided to go looking for other catalogs, and I found: Israel's !

A M7 earthquake occurred an hour ago in Papua New Guinea. Here, the Australian Plate is colliding with the Pacific Plate, and ... it's complicated, and extremely seismic.

Why did a M5.5 earthquake occur today in the Flores Sea, north of the island of Sumbawa, Indonesia and 100 km NE of Tambora volcano?

Today's M4.5 earthquake near Samandağ, Turkey, is the largest aftershock in the region since March 1. This area was hit by shaking in the M7.8 mainshock on Feb 6, the triggered M7.5 on the same day, and then a damaging M6.3 aftershock on Feb 20.

Yesterday's M4.6 earthquake in Nepal occurred near the eastern edge of the 2015 M7.8 Nepal earthquake zone. The mainshock on April 25, 2015 was followed by a large aftershock on May 12, 2015 - yesterday's quake was close to that aftershock location.

A M4.6 earthquake just occurred between the cities of Gaziantep and Osmaniye, Turkey. Aftershocks of this magnitude are fairly common since the Feb. 6 earthquakes, but not so much in this region - this is the biggest aftershock in the region in over 3 weeks.

Do you wish you could sign up for earthquake early warnings, but there isn't a system in your country? Android phones have a built-in alert system that uses the accelerometers in the 2+ billion Android phones around the world.

A M6.3 earthquake just occurred off the coast of Chile. Not damaging - it's too far offshore. The earthquake occurred within the rupture area of the M8.8 2010 Maule, Chile earthquake (shown in red and yellow).