Anthony Lomax
@alomaxnet.bsky.social
Earthquake happenings+tidbits, maps, machine learning.I'm ALomax Scientific: earthquake monitoring and analysis
🤑OPEN ACCESS🤑 In a new paper, lead by Sylvert Paul, we precisely relocate the 2021 M 7.2 Nippes, Haiti, earthquake sequence using broadband and low-cost, citizen-hosted, seismometers.
Strain is partitioned on strike-slip, reverse, and obliquely-slipping faults.
authors.elsevier.com/sd/article/S...
Strain is partitioned on strike-slip, reverse, and obliquely-slipping faults.
authors.elsevier.com/sd/article/S...
November 14, 2025 at 7:33 AM
🤑OPEN ACCESS🤑 In a new paper, lead by Sylvert Paul, we precisely relocate the 2021 M 7.2 Nippes, Haiti, earthquake sequence using broadband and low-cost, citizen-hosted, seismometers.
Strain is partitioned on strike-slip, reverse, and obliquely-slipping faults.
authors.elsevier.com/sd/article/S...
Strain is partitioned on strike-slip, reverse, and obliquely-slipping faults.
authors.elsevier.com/sd/article/S...
A longer sonification with slower sound rate factor (1000) gives a clearer and more detailed impression of the evolution of the "drumbeat" seismicity, which continues with increasing frequency right up to the largeest (landslide failure?) signal, but not after.
August 14, 2025 at 1:48 PM
A longer sonification with slower sound rate factor (1000) gives a clearer and more detailed impression of the evolution of the "drumbeat" seismicity, which continues with increasing frequency right up to the largeest (landslide failure?) signal, but not after.
... inspired by this seismogram at earthquake.alaska.edu/major-landsl...
August 13, 2025 at 6:47 AM
... inspired by this seismogram at earthquake.alaska.edu/major-landsl...
Amazing how the precursor seismicity has a very regular drum-beat with increasing rate of occurrence. This is clear in a sonified version:
August 13, 2025 at 6:46 AM
Amazing how the precursor seismicity has a very regular drum-beat with increasing rate of occurrence. This is clear in a sonified version:
M7.3 #Earthquake offshore of #Kamchatka #Russia 20 min after M6.7 event in same area. alomax.free.fr/projects/ear...
July 20, 2025 at 7:04 AM
M7.3 #Earthquake offshore of #Kamchatka #Russia 20 min after M6.7 event in same area. alomax.free.fr/projects/ear...
Not many stations nearby on this map:
ds.iris.edu/gmap/#startt...
ds.iris.edu/gmap/#startt...
June 24, 2025 at 1:03 PM
Not many stations nearby on this map:
ds.iris.edu/gmap/#startt...
ds.iris.edu/gmap/#startt...
no comment
www.theguardian.com/technology/2...
www.theguardian.com/technology/2...
June 1, 2025 at 6:41 AM
no comment
www.theguardian.com/technology/2...
www.theguardian.com/technology/2...
Doesn't this mean that the bar for France in this graph should be about 3x longer if we want to compare R&D effort and potential impact?
May 5, 2025 at 9:58 AM
Doesn't this mean that the bar for France in this graph should be about 3x longer if we want to compare R&D effort and potential impact?
Rapid, first-motion mechanism shows strike-slip faulting.
alomax.free.fr/projects/ear...
alomax.free.fr/projects/ear...
April 23, 2025 at 10:23 AM
Rapid, first-motion mechanism shows strike-slip faulting.
alomax.free.fr/projects/ear...
alomax.free.fr/projects/ear...
April 23, 2025 at 10:05 AM
April 23, 2025 at 9:59 AM
I think that is a bug, not a feature. Magnitude uncertainty is more like +/- 0.2 or 0.3. It will be interesting to learn what happened. earthquake.usgs.gov/earthquakes/...
* BTW, I though you were *outdoors* in colorful (colourful) attire an watching political speeches at Coachella! 😜
* BTW, I though you were *outdoors* in colorful (colourful) attire an watching political speeches at Coachella! 😜
April 14, 2025 at 7:00 PM
I think that is a bug, not a feature. Magnitude uncertainty is more like +/- 0.2 or 0.3. It will be interesting to learn what happened. earthquake.usgs.gov/earthquakes/...
* BTW, I though you were *outdoors* in colorful (colourful) attire an watching political speeches at Coachella! 😜
* BTW, I though you were *outdoors* in colorful (colourful) attire an watching political speeches at Coachella! 😜
We examined and discussed these issues in the paper "Major California faults are smooth across multiple scales at seismogenic depth" seismica.library.mcgill.ca/article/view...
April 2, 2025 at 1:19 PM
We examined and discussed these issues in the paper "Major California faults are smooth across multiple scales at seismogenic depth" seismica.library.mcgill.ca/article/view...
Surface rupture of bsky.app/profile/maxv... suggests a remarkably smooth & geometrically simple rupture surface at depth: Black line is a simple spline controlled only by the two blue points.
Perhaps important implications for large earthquake rupture physics & why this may be a super-shear rupture.
Perhaps important implications for large earthquake rupture physics & why this may be a super-shear rupture.
April 2, 2025 at 11:53 AM
Surface rupture of bsky.app/profile/maxv... suggests a remarkably smooth & geometrically simple rupture surface at depth: Black line is a simple spline controlled only by the two blue points.
Perhaps important implications for large earthquake rupture physics & why this may be a super-shear rupture.
Perhaps important implications for large earthquake rupture physics & why this may be a super-shear rupture.
The surface rupture suggests an extremely smooth and geometrically simple rupture surface at depth.
[Black line is a simple spline controlled by only the two blue points]
Perhaps important consequences for large earthquake rupture physics and why this may be a super-shear rupture.
[Black line is a simple spline controlled by only the two blue points]
Perhaps important consequences for large earthquake rupture physics and why this may be a super-shear rupture.
April 2, 2025 at 10:37 AM
The surface rupture suggests an extremely smooth and geometrically simple rupture surface at depth.
[Black line is a simple spline controlled by only the two blue points]
Perhaps important consequences for large earthquake rupture physics and why this may be a super-shear rupture.
[Black line is a simple spline controlled by only the two blue points]
Perhaps important consequences for large earthquake rupture physics and why this may be a super-shear rupture.
Same seismogram at Garni, Armenia (~5000 km from the earthquake) without filtering. alomax.free.fr/webtools/sgw...
March 28, 2025 at 7:19 AM
Same seismogram at Garni, Armenia (~5000 km from the earthquake) without filtering. alomax.free.fr/webtools/sgw...
M7.7 #earthquake #Myanmar High-frequency seismograms suggest around 2 minutes of rupture duration (and shaking) for the first, main event alomax.free.fr/webtools/sgw...
March 28, 2025 at 7:14 AM
M7.7 #earthquake #Myanmar High-frequency seismograms suggest around 2 minutes of rupture duration (and shaking) for the first, main event alomax.free.fr/webtools/sgw...
Anthony Lomax @alomaxnet.bsky.social
·
1m
probably really about 5 sec of shaking, judging by the
RaspberryShake seismometer in the shed
·
1m
probably really about 5 sec of shaking, judging by the
RaspberryShake seismometer in the shed
March 18, 2025 at 6:01 PM
Anthony Lomax @alomaxnet.bsky.social
·
1m
probably really about 5 sec of shaking, judging by the
RaspberryShake seismometer in the shed
·
1m
probably really about 5 sec of shaking, judging by the
RaspberryShake seismometer in the shed
Felt that one. Quite a long duration of shaking (5-10sec?) for an M4 #earthquake. SE #France
www.emsc-csem.org/Earthquake_i...
www.emsc-csem.org/Earthquake_i...
March 18, 2025 at 5:52 PM
Felt that one. Quite a long duration of shaking (5-10sec?) for an M4 #earthquake. SE #France
www.emsc-csem.org/Earthquake_i...
www.emsc-csem.org/Earthquake_i...
For more details, see the Seismica paper ☝️, or this poster summarizing the method and results from the paper: zenodo.org/records/1151...
March 4, 2025 at 2:12 PM
For more details, see the Seismica paper ☝️, or this poster summarizing the method and results from the paper: zenodo.org/records/1151...
Based on patterns in the surrounding seismicity, the *seismicity-stress* procedure images fault slip for earthquakes as well as crack opening due to magmatic or fluid movement. The method can also image very large earthquakes, such as the 2023 M7.8 and M7.5 Kahramanmaraş, Turkey (Türkiye) events:
March 4, 2025 at 2:12 PM
Based on patterns in the surrounding seismicity, the *seismicity-stress* procedure images fault slip for earthquakes as well as crack opening due to magmatic or fluid movement. The method can also image very large earthquakes, such as the 2023 M7.8 and M7.5 Kahramanmaraş, Turkey (Türkiye) events:
This *seismicity-stress* procedure constructs 3D maps of finite-faulting slip potential by correlating point-source ΔCFS kernels across the distribution of seismicity around the earthquake:
March 4, 2025 at 2:12 PM
This *seismicity-stress* procedure constructs 3D maps of finite-faulting slip potential by correlating point-source ΔCFS kernels across the distribution of seismicity around the earthquake:
Under the Coulomb failure stress criteria, earthquake fault slip occurs when shear stress is sufficiently high and normal stress sufficiently low. Large earthquake rupture will favor triggering of surrounding aftershocks within the positive lobes (red) of change in Coulomb failure stress (ΔCFS).
March 4, 2025 at 2:12 PM
Under the Coulomb failure stress criteria, earthquake fault slip occurs when shear stress is sufficiently high and normal stress sufficiently low. Large earthquake rupture will favor triggering of surrounding aftershocks within the positive lobes (red) of change in Coulomb failure stress (ΔCFS).
NLL-SSST-coherence high-precision earthquake location catalog for the 2025 #Santorini #Amorgos #earthquake swarm.
Based on data from Institute of Geodynamics of the National Observatory of Athens (NOA-IG).
Download & details: doi.org/10.5281/zeno...
Based on data from Institute of Geodynamics of the National Observatory of Athens (NOA-IG).
Download & details: doi.org/10.5281/zeno...
March 3, 2025 at 6:37 AM
NLL-SSST-coherence high-precision earthquake location catalog for the 2025 #Santorini #Amorgos #earthquake swarm.
Based on data from Institute of Geodynamics of the National Observatory of Athens (NOA-IG).
Download & details: doi.org/10.5281/zeno...
Based on data from Institute of Geodynamics of the National Observatory of Athens (NOA-IG).
Download & details: doi.org/10.5281/zeno...