How Often Do Earthquakes Occur?

Courtesy of iris (now earth consortium)

Earth is an active place and earthquakes are always happening somewhere. In fact, the National Earthquake Information Center locates about 12,000-14,000 earthquakes each year! This fact sheet illustrates information on the frequency of earthquakes of various magnitudes, along with details on the effects of earthquakes and the equivalent energy release. On average, Magnitude 2 and smaller earthquakes occur several hundred times a day world wide. Major earthquakes, greater than magnitude 7, happen more than once per month. “Great earthquakes”, magnitude 8 and higher, occur about once a year.


  • Earthquakes are always happening somewhere.
  • For each step up in magnitude the annual number of earthquakes decreases (roughly) by a factor of 10. 
  • For each step up in magnitude an earthquake releases 30 times more energy.
  • While the number of earthquakes that can be detected and located each year has been increasing, this doesn’t mean that the annual average number of earthquakes has increased.     

this image can be found here –>>

March Math-ness marathon …. Dallas, TX – win $50!

If anything takes you to Dallas this March, make sure you participate in… The March MATHness Challenge:

This March marks the beginning of a great new way to engage children in grades 4-8 with math and STEM embedded in the environment around them – with a chance for them to win $50 every week as well!  The Challenge is open to children, school-based and out of school K-12 educators, parents and families. We’ve created a collection of over a hundred multi-media math walk stops across Dallas for children to explore and learn from, developed by us at the talkSTEM nonprofit alongside SMU, under the walkSTEM and MathFinder initiatives – with support from the National Science Foundation as well as several Dallas-based grant-giving organizations. Children and educators alike can download the free Otocast app to start visiting stops in 15 participating locations across Dallas and start earning raffle entries, whether independently or in teams with other classmates. For more information about this free opportunity, along with testimonials from teachers and other educators, come on over to

You can go on these math and STEM walks anytime you are in Dallas – even after the Challenge is over if you’d like to have the experience.  It’s all free, self-guided, and fun.  No need to book or coordinate anything!

Public Feedback Webinar – you’re invited!

The National Assessment Governing Board sets policy for the National Assessment of Educational Progress (NAEP), also known as The Nation’s report Card – the country’s largest ongoing assessment of student achievement. A key responsibility of the Governing Board is developing NAEP frameworks, which guide the content of NAEP assessments.

Revisions to the NAEP Science Assessment Framework, which determines what content and skills in science are to be assessed in grades 4, 8 and 12 will be implemented for the 2028 administration of the NAEP Science Assessment. Steering and Development Panels, which represent a diverse range of expertise and stakeholders, have been reviewing the framework for several months and outlined their initial recommendations, the first since 2005. 

As part of the process, a working draft of the recommended updates is made available for public review. In partnership with the Governing Board, we are hosting an informational webinar to share information about the updates and explain the steps for our network to share feedback. 

March 21, 2023 11:00 AM: Webinar for all audiences, focusing on updates to the NAEP Science Assessment Framework.

March 28, 2023 3:00 PM: Webinar for stakeholders interested in the intersection of science, engineering, and technology.

March 31, 2023 11:00 AM: Webinar for stakeholders in science education. 

April 11, 2023 11:00 AM: Webinar for all audiences, focusing on updates to the NAEP Science Assessment Framework.

For additional information, visit:

The Ides of March, Part 2

ECUADOR – A damaging, powerful magnitude M6.8 earthquake occurred yesterday, 03/18/2023 at 17:12 UTC onshore Ecuador. The epicenter is approximately 36 polar degrees away from Raspberry Shake Station R5DDF in Spring, TX. The quake was recorded very well – and rare – PcP** wave phase (P-wave which has been refracted thru the mantle, reflected off the outer core, and travelled back thru the mantle to the Earth’s surface at our precise location) and it is observed around 17:22 UTC. Shaking was felt as far away as Peru.

More information about the damages and human impact can be read HERE —>>

**Earth schematic edited from Univ of WI, River Falls

The Ides of March, Part 1

KERMADEC ISLANDS – a magnitude M7.0 earthquake occurred yesterday, 03/16/2023 at 00:56hrs UTC offshore the Kermadec Islands. Despite the shallow focal depth (~22m), the low-populated areas are not likely to have seen major damages. The event was recorded in Spring, TX at Raspberry Shake Station R5DDF, the Surface waves shown below, and a LP 0.08Hz filter applied.

March 1st – Girls in STEM “DAY ACROSS TEXAS”

Each March 1, Texas recognizes Texas Girls in STEM Day. The day marks a chance to celebrate and encourage the participation of girls in this state in fields related to science, technology, engineering, and mathematics — and is the result of House Bill 3435, passed by Representative Rhetta Bowers during the 86th Regular Session. The legislation encourages all across the state to embrace programs, ceremonies, and class instruction that emphasizes women in STEM-related careers. Texas Girls in STEM Day gives many young girls the opportunity to learn, ask questions, and dive deeper into subjects they may not have been encouraged to explore otherwise.

Learn more about just a few GREAT “Girls in STEM” Events across the State this year–>>>

STEM for Girls at Abilene Christian University

STEM Girl Day at UT Austin

Texas Science Festival 2023

Women In Tech Texas 2023

Girls Exploring Math and Science (GEMS) at The Houston Museum of Natural Science

Girls in Science – FREE SUMMER CAMP (Woods Hole, MA)

Applications are now open for our 2023 Girls in Science Fellowship! This fully-funded 7-day summer opportunity empowers young women from MA to explore different paths in science. They’ll work with WHOI scientist Laela Sayigh and other STEAM professionals to investigate marine mammal bioacoustics. Selected applicants will reside for one week in August as a cohort in Woods Hole, MA, building relationships with their fellows and professional role models – women of all backgrounds in various STEAM careers. Register for the info session to learn more!

Learn more:

“Sorry, out busy, try again later.”

“Are we having more earthquakes lately?”

Depends – how long of a timeframe does “lately” equal? A month? year? Decade? Era? Many large, powerful earthquakes have been in the news lately…. it does seem like the Earth “is busy” and we should “ask again later.” This month is not yet over, and we have already recorded several large magnitude, global events here in Spring, TX at Raspberry Shake Station R5DDF. Take a look ~ unless otherwise noted, no significant damages or human loss was incurred from these events.


Why save the best for last (in the month)? These INTRIGUING OBSERVATIONS were made at Station R5DDF; apparently, a few polar degrees does matter to epicentral distance….take these events shown in Figures 1a and 1b – both earthquakes had the same magnitude (M7.0), occurred in the same region of the World AND had similar hypocenter depths – NOTE that one event was detected and recorded at our site location, and the other event was not. How can we explain these observations?

Figure 1a. January 08, 2023, 12:32 UTC – (Vanuatu) A magnitude M7.0 earthquake occurred in this area of the Ring of Fire. A 0.2 to 1.2 Hz BP filter has been applied to the extracted seismogram – no apparent signal is observed. The epicentral distance is approximately 104 polar degrees away from Spring, TX.

Figure 1b. January 18, 2023, 06:06 UTC – (Indonesia) The same magnitude, an M7.0, earthquake occurred in nearby Indonesia. The same 0.2 to 1.2 Hz BP filter has been applied to the extracted seismogram. The epicentral distance of this event is approximately 128 polar degrees away. How can we explain these two observations?


Figure 2. January 09, 2023, 17:47 UTC – (Indonesia) A very powerful magnitude M7.6 earthquake occurred in Indonesia – not a new geologic experience for the region. A 0.5 Hz LP filter has been applied to the extracted seismogram.

Figure 3. January 20, 2023, 11:23 UTC – (Guadeloupe, Caribbean Sea) a large magnitude M6.2 earthquake occurred offshore this tiny island – the hypocenter was approximately 166km deep. A 0.5 Hz LP filter has been applied to the extracted seismogram.

Figure 4. January 20, 2023, 22:09 UTC – (Argentina) a very powerful magnitude M6.8 (and deep!) earthquake shook this Country. A 0.5 Hz LP filter has been applied to the extracted seismogram.

Figure 5. January 24, 2023, 18:37 UTC – (Argentina) a strong after-shock (also, deep) earthquake occurred near the main shock’s epicenter. The magnitude M6.4 event caused little to no damage because the epicenter was not nearby populous areas. A 0.8 Hz LP filter has been applied to the extracted seismogram.

Listen and Learn

This week I had the honor to participate as a Judge for the 2023 SCI://TECH Science Fair — Earth and Environmental Sciences Division, Junior High. This annual competition is organized by the Education for Tomorrow Alliance (EFTA). This year’s focus was to 1. encourage and empower student participants to learn the Scientific Method, and 2. build self-confidence in their presentation skills. Listening and having an engaging dialogue was my top priority – I heard about very interesting investigations – see pics for a sample of the projects I had the pleasure to evaluate. Students’ images and names have been purposefully removed to protect privacy. WHAT A GRAND DAY!

Education for Tomorrow Alliance engages the business community with local private and public schools, offering 13 science, technology, engineering, and math competitions and events. Run as a partnership of EFTA volunteers and local educators, the SCI://TECH Exposition includes one of the largest regional science fairs in the nation reaching thousands of students each year and qualifying students to compete in the Science & Engineering Fair of Houston, as well as state and international competitions. 

The “quiet” Pacific Northwest

OFFSHORE OREGON – yesterday, Jan 11, 2023 at 10:17 UTC, a magnitude M5.0 earthquake occurred offshore Oregon. No felt shaking has been reported yet. The hypocenter was shallow at 10 km depth. Observations at RS Station R5DDF in Spring, TX that the event was not detected – with confidence. See the extracted seismogram below – a 0.2 to 0.8 Hz BP filter has been applied.

THE DATA APPEARS TO BE “MISSING” ….WHY IS THIS INTERESTING? So glad you asked 😉 Scientific theories are built on (1) what we think we know, (2) what we don’t know and (3) how much we don’t know that which we don’t know 😆 In other words, we can make reasonable deductions and inferences about the Earth when we **don’t** detect earthquakes – they enable us to ask the “WHY?” questions…. why weren’t the seismic waves detected at my location? why is the Earth filtering out the signal? why wasn’t shaking felt onshore? And many more inquiries – I believe that it is far more fascinating to ask the “WHY?” questions when data is “missing” (is it really missing?).

Understanding boundary conditions in a scientific inquiry is just as important as discovering the obvious phenomena.

#whereismywiggle, #whatsthatwiggle