Always impressed with the quality and speediness of your response posts! Using your host fault guess and the first interferogram from COMET, Kelian Dascher-Cousineau and I found a bit of surface rupture in Planet labs imagery: https://www.planet.com/stories/tibet-surface-rupture-aSrfDSvNR (slide to see pre and post-earthquake imagery). The length I was able to clearly map (which is a bit more than shown in this image) is still very modest (and segmented!) compared to the size of the event. I assume better data and more careful mapping in the future will show more.
I hope you know Mike Searle who has done decades of field and structural geology in the Himalaya, Tibet, and adjacent ranges of Asia. Mike has a lot to say on detachment and normal faults to the south of the recent M 7.1 earthquake near Tingri. Mike's photos of the world's highest mountain and nearby peaks are spectacular and the structural overlays informative. Jay Namson and I met Mike years ago on a field trip in Tibet. I'm always amazed on how much he has accomplished and revealed about the geology of this region.
Excellent article, but please fix the date (year) in the first paragraph. Oddly enough I didn't notice it when I read the article in English, but only after I went to check Google's Tibetan translation.
Oops! I guess we're not quite ready for the new year. Thanks, it has been fixed. I have upgraded your account to "paid" status for one month as thanks!
Why, thank you so much! I have also shared your article in some private earth science discord servers to which I belong—I hope it may net you some paid subscribers in return.
Again I find myself in awe of your (collective-I presume more than one mind and probably AI are involved) ability to produce and provide comprehensive and deeply documented and data rich analysis of current seismic activity. Thanks. One humble question I’m looking to answer is the velocities this shallow event produced. Was the epicenter ground movement rapid?
Hi John, yes, you can see the rupture fronts in Figure 4 (bottom) - they show how many seconds had passed since the start of the rupture. The slip happened within ~20 seconds.
And, yes, there are two of us - but no AI! We usually each take one part of the story and then merge and edit. It would be much harder as one person! That happens sometimes but it's usually a joint effort.
Thanks so much Ms. Hubbard. I was reading USGS data when you posted this but hadn’t determined V yet, so thanks. So if total slip was 1.6 meters over 20 seconds then 8 cms per second… The ‘94 Northridge is my standard so if my rudimentary calculation is somewhat accurate then this was much slower by comparison. And congratulations to you two on your professional accomplishment in these works.
Ah, the 20 seconds is actually something else - it represents how long it took for the rupture to propagate from the origin to the end of the fault (about 40 km away) - so about 2 km/s. I am not sure about the rate of slip at a specific location, but surely happens over a much shorter period of time.
Always impressed with the quality and speediness of your response posts! Using your host fault guess and the first interferogram from COMET, Kelian Dascher-Cousineau and I found a bit of surface rupture in Planet labs imagery: https://www.planet.com/stories/tibet-surface-rupture-aSrfDSvNR (slide to see pre and post-earthquake imagery). The length I was able to clearly map (which is a bit more than shown in this image) is still very modest (and segmented!) compared to the size of the event. I assume better data and more careful mapping in the future will show more.
Thanks, Alba! We mentioned your work in our update post - I hope that's okay.
Kyle and Judith,
I hope you know Mike Searle who has done decades of field and structural geology in the Himalaya, Tibet, and adjacent ranges of Asia. Mike has a lot to say on detachment and normal faults to the south of the recent M 7.1 earthquake near Tingri. Mike's photos of the world's highest mountain and nearby peaks are spectacular and the structural overlays informative. Jay Namson and I met Mike years ago on a field trip in Tibet. I'm always amazed on how much he has accomplished and revealed about the geology of this region.
https://lnkd.in/gwyDnN9U
Colliding Continents: A Geological Exploration of the Himalaya, Karakoram, and Tibet https://a.co/d/8pt8mYZ
Excellent article, but please fix the date (year) in the first paragraph. Oddly enough I didn't notice it when I read the article in English, but only after I went to check Google's Tibetan translation.
གཞིས་རྩེའི་མི་མང་ལ་ཉེན་ཁ་ཁྱོན་ནས་མ་ཡོང་བར་ཤོག
Oops! I guess we're not quite ready for the new year. Thanks, it has been fixed. I have upgraded your account to "paid" status for one month as thanks!
Why, thank you so much! I have also shared your article in some private earth science discord servers to which I belong—I hope it may net you some paid subscribers in return.
Excellent update! Informative historic background too on cross section studies. Thanks!
Again I find myself in awe of your (collective-I presume more than one mind and probably AI are involved) ability to produce and provide comprehensive and deeply documented and data rich analysis of current seismic activity. Thanks. One humble question I’m looking to answer is the velocities this shallow event produced. Was the epicenter ground movement rapid?
Hi John, yes, you can see the rupture fronts in Figure 4 (bottom) - they show how many seconds had passed since the start of the rupture. The slip happened within ~20 seconds.
And, yes, there are two of us - but no AI! We usually each take one part of the story and then merge and edit. It would be much harder as one person! That happens sometimes but it's usually a joint effort.
Thanks so much Ms. Hubbard. I was reading USGS data when you posted this but hadn’t determined V yet, so thanks. So if total slip was 1.6 meters over 20 seconds then 8 cms per second… The ‘94 Northridge is my standard so if my rudimentary calculation is somewhat accurate then this was much slower by comparison. And congratulations to you two on your professional accomplishment in these works.
Ah, the 20 seconds is actually something else - it represents how long it took for the rupture to propagate from the origin to the end of the fault (about 40 km away) - so about 2 km/s. I am not sure about the rate of slip at a specific location, but surely happens over a much shorter period of time.
Ah! Yes!!very important difference. Thanks for clarifying my misrepresentation of the facts and misunderstanding.
Typical ground motion velocities near a magnitude 7 shallow earthquake epicenter are around 1 meter per second.
Thanks. That helps me put the ‘94 Northridge 170cms/second velocity in a proper perspective as well as this subject event.