Oct 15, 2023Liked by Judith Hubbard & Kyle Bradley
The interferograms that I saw on LinkedIn had a noticeable phase discontinuity on the south side, so at least one of the first set of quakes ruptured to the surface on a north-dipping fault.
I think I found the post you're talking about - with a video showing the difference between ascending and descending, right? Do you have any ideas as to why the patterns are so different, in both location of deformation and number of fringes? I agree that the descending pass looks like it's capturing a short surface rupture (or fold scarp), but I'm puzzled about some of the variations.
I would like to express my appreciation for your informative updates on the Herat earthquakes. Your analysis has been invaluable, and I am grateful for your insights.
In your article, you mentioned that a larger earthquake could be triggered on either the same fault system or a larger one nearby. Today, several earthquakes of magnitudes 3.7, 3.5, and two 2.7 struck around Mashhad City, according to the Iranian Seismological Center (www.irsc.ut.ac.ir).
Given these recent events, I am curious to know your thoughts on the seismic activity in the region. Is there a high risk of a large earthquake in the region, particularly in Mashhad and Neyshabur, which both cities have been affected by major earthquakes in the past? What do these recent events tell us about the seismic activity in the region?
I would be grateful for any insights you can share.
Hi Emad, thanks for the kind words about our blog. It is always great to hear from people who live in or care about earthquake prone areas. Small earthquakes are common in eastern Iran, more common than around Herat in the recent past. The occurrence of small earthquakes really isn't enough of a signal to change any interpretation of earthquake hazard in the near term. The large majority of earthquakes are not foreshocks. So, the advice is to carry on life as per usual - but with the constant goal of always trying to improve resilience because earthquakes are inevitable in active regions. I view these kinds of small earthquakes as fortunate reminders that many of us (in earthquake prone regions) are living in borrowed time, and that anything we do today to improve our situation, even as simple as securing shelves or preparing an emergency kit, is a tremendous improvement versus doing nothing. I'm happy to pass on some links about earthquake preparation if you would find them useful. Best wishes! Kyle
Dear Kyle, Thank you so much for your informative reply.
The Herat earthquakes were completely felt in eastern Iran as well as Mashhad. Since then, people have been anxiously following the news related to the recent earthquakes.
I was particularly interested in your analysis of the repetition of 6.3 earthquakes. I had not found a proper explanation for this before, and your blog post helped me to better understand the situation.
I want to express my sincere gratitude for the important work that you are doing. Your research and analysis are helping to educate the public about earthquakes and to make our communities safer.
Most people in Mashhad are aware of the importance of earthquake preparedness, but their main concern is the safety of their homes and other structures, many of which are old and in need of reinforcement. They are also concerned about how the Iranian regime will manage the situation in the event of a major earthquake.
However, there are some positive developments. For example, earthquake preparedness is now taught in schools, and even young children are learning what to do in the event of an earthquake. My first-grade nephew recently explained to me what to do during an earthquake, which I found very encouraging.
These earthquakes definitely have me thinking about how we communicate such unusual sequences to emergency managers. I'm honest when I tell them that there is always a chance that an earthquake could be followed by another one the same size or larger. Having to say that again and again over a short period of time is something I haven't thought about and probably need to think about a bit more.
Yes, I first was in this situation with the 2019 Cotabato earthquakes in the Philippines - a woman I knew had family in the area, and her home there was damaged in the first earthquake. We talked about what to expect - only to be surprised by the three later earthquakes. I eventually applied for funding to work on those earthquakes because of that experience (the paper is in progress, but doesn't answer the question in a very useful way). I've been a lot more cautious ever since.
The interferograms that I saw on LinkedIn had a noticeable phase discontinuity on the south side, so at least one of the first set of quakes ruptured to the surface on a north-dipping fault.
I think I found the post you're talking about - with a video showing the difference between ascending and descending, right? Do you have any ideas as to why the patterns are so different, in both location of deformation and number of fringes? I agree that the descending pass looks like it's capturing a short surface rupture (or fold scarp), but I'm puzzled about some of the variations.
Thanks for another update on this earthquake sequence.
I would like to express my appreciation for your informative updates on the Herat earthquakes. Your analysis has been invaluable, and I am grateful for your insights.
In your article, you mentioned that a larger earthquake could be triggered on either the same fault system or a larger one nearby. Today, several earthquakes of magnitudes 3.7, 3.5, and two 2.7 struck around Mashhad City, according to the Iranian Seismological Center (www.irsc.ut.ac.ir).
Given these recent events, I am curious to know your thoughts on the seismic activity in the region. Is there a high risk of a large earthquake in the region, particularly in Mashhad and Neyshabur, which both cities have been affected by major earthquakes in the past? What do these recent events tell us about the seismic activity in the region?
I would be grateful for any insights you can share.
Thank you for your time and consideration.
Hi Emad, thanks for the kind words about our blog. It is always great to hear from people who live in or care about earthquake prone areas. Small earthquakes are common in eastern Iran, more common than around Herat in the recent past. The occurrence of small earthquakes really isn't enough of a signal to change any interpretation of earthquake hazard in the near term. The large majority of earthquakes are not foreshocks. So, the advice is to carry on life as per usual - but with the constant goal of always trying to improve resilience because earthquakes are inevitable in active regions. I view these kinds of small earthquakes as fortunate reminders that many of us (in earthquake prone regions) are living in borrowed time, and that anything we do today to improve our situation, even as simple as securing shelves or preparing an emergency kit, is a tremendous improvement versus doing nothing. I'm happy to pass on some links about earthquake preparation if you would find them useful. Best wishes! Kyle
Dear Kyle, Thank you so much for your informative reply.
The Herat earthquakes were completely felt in eastern Iran as well as Mashhad. Since then, people have been anxiously following the news related to the recent earthquakes.
I was particularly interested in your analysis of the repetition of 6.3 earthquakes. I had not found a proper explanation for this before, and your blog post helped me to better understand the situation.
I want to express my sincere gratitude for the important work that you are doing. Your research and analysis are helping to educate the public about earthquakes and to make our communities safer.
Most people in Mashhad are aware of the importance of earthquake preparedness, but their main concern is the safety of their homes and other structures, many of which are old and in need of reinforcement. They are also concerned about how the Iranian regime will manage the situation in the event of a major earthquake.
However, there are some positive developments. For example, earthquake preparedness is now taught in schools, and even young children are learning what to do in the event of an earthquake. My first-grade nephew recently explained to me what to do during an earthquake, which I found very encouraging.
Thank you again for your time and expertise.
All the best, Emad
These earthquakes definitely have me thinking about how we communicate such unusual sequences to emergency managers. I'm honest when I tell them that there is always a chance that an earthquake could be followed by another one the same size or larger. Having to say that again and again over a short period of time is something I haven't thought about and probably need to think about a bit more.
Yes, I first was in this situation with the 2019 Cotabato earthquakes in the Philippines - a woman I knew had family in the area, and her home there was damaged in the first earthquake. We talked about what to expect - only to be surprised by the three later earthquakes. I eventually applied for funding to work on those earthquakes because of that experience (the paper is in progress, but doesn't answer the question in a very useful way). I've been a lot more cautious ever since.