This morning at 12:09hrs UTC (7:09 am CST), Ecuador shook from a moderate magnitude mb 5.3 earthquake. The focal depth was approximately 33kms deep. Although the event was barely detected at Station E1TX, we were able to interpret our own mb magnitude perfectly matched compared to the USGS reported mb magnitude:
Station E1TX detected and recorded the M6.3 earthquake in New Zealand. Below, the red arrow points the first arrival, the PP wave phase. The surface waves are also clearly shown in 08:00 hour (UTC).
LISTEN to the Earth Break (in Montana), Part 4: We enjoy listening to the rocks strain and stress (sometimes break) during earthquakes. An infrequent event, please take a moment to listen to these (3) different audio files of the July 6, 2017 16:30hrs UTC MONTANA earthquake (Mww=5.9). Note that the files reflect time sped up three ways: x900 (1sec=15 minutes), x1800 (1sec=30 mins) and x3600 (1 sec=1 hour). Courtesy of EarthSound.
Listen to the Earth Part 5.
TWO TEACHABLE MOMENTs: During late June a swarm of small magnitude earthquakes occurred near West Yellowstone, MT. Hundreds of events with magnitudes less than M3.5 (mb) stirred the area for several weeks. Near Lincoln, MT, a large magnitude M5.9 (Mww) earthquake woke up residents across the State at 16:30hrs UTC (12:30 a.m. MST) and was approximately 14 kms deep.
Below is a snapshot of the event on the seismometer -and- a ground shaking intensity map based on reports from local citizens. Ground shaking was the most intense near the epicenter. Why was shaking felt so far across the Big Sky State?
This morning at 16:07hrs UTC (11:07 CST) a moderately sized earthquake shook Guatemala. It’s possible that this event, with a focal depth of 43kms, is a late aftershock of the magnitude 6.8 (Mww) earthquake on June 23, 2017 with a similar depth.
Karnes City, TX had their ground shaken this morning by a magnitude 3.0 (mb_Lg) earthquake at 09:00 hrs UTC (4:00 am CST). The event was approximately 5.5kms deep; it was recorded very well at Station E1TX.
Late this afternoon a magnitude 6.0 (Mww) earthquake occurred offshore Ecuador at 22:29hrs UTC and was 10kms deep. On the seismogram, you can distinctly see the P, PP, and then the PPP wave phases.
Hurricane Cindy made landfall on the Louisiana Gulf Coastline early Thursday at 22June2017. The storm, as expected, brought heavy rainfall and rough waters on the coastline. Station E1TX was close enough to “monitor” the track of the storm relative to Spring/Houston using the EQ-1 educational seismograph. As Cindy approached before landfall, you can observe an increase in the seismic amplitudes on the screenshots (slideshow below); once Cindy began heading to the East Coast, and thus further away from the Houston metro area, we begin to see the seismic amplitudes decrease over time. Fascinating!
For more information about Cindy’s landfall and continued track, see here —>> http://www.cnn.com/2017/06/22/us/tropical-storm-cindy-landfall/index.html
Another M6.8 (Mww) earthquake has damaged Guatemala now twice within 10 days. The epicenter was located near the 17/05/2017 event and it’s after shocks. The seismological community will be debating whether this earthquake is a different event, or a powerful after shock. Today’s earthquake had magnitude 6.2 (mb), occurred at 12:31 hrs UTC and was approximately 47kms deep. It is fascinating studying the seismogram.
TEACHABLE MOMENT: INTRAPLATE EARTHQUAKES
Beginning on 16June2017, and observing our earthquake tracking map until 22June2017, we have observed dozens of magnitude M>2.5 earthquakes across the Continental United States. These events are referred to as “intraplate earthquakes” because they occur far from a tectonic plate boundary. What geologic mechanisms cause these special earthquakes? What assumptions may we hypothesize if we observe a “swarm”, or cluster, of these events in one location?
Map ‘A’
After tracking the epicenters of global earthquakes for more than 50+ years, we note that earthquakes, and other surface features such as volcanoes, form a map pattern (Map ‘B’) allowing scientists to deduce the Theory of Plate Tectonics (see map below, author unknown). NOTE: the earthquakes in Map ‘A’ are far away from the distinct pattern of the tectonic plates – they are referred to as “intraplate earthquakes”.
Map ‘B’
