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Thank you for sharing this, Eric! So happy to see NiSAR helping the community in action.

Dr. Eric J. Fielding, PhD @ericjfielding.bsky.social · 28/06/2026

Reposted by Baoning Wu

NASA-ISRO SAR (NISAR) satellite imaged Venezuela June 25. NISAR SAR interferometry (InSAR) enabled calculation of surface displacement. Displacements have red tones for east and blue tones for west, with white in middle near-zero over fault rupture. Fault ruptured far to east under ocean. #venezuela

Map of north-central Venezuela with NISAR line-of-sight displacement map shown in false color varying from red to white to blue. Red land moved east (towards satellite) and blue land moved west. InSAR only measures land, so ocean and lakes have no measurements. Background map from Google satellite natural-color images on land and bathymetry in ocean.

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SPECFEM @specfem.org · 28/06/2026

This is very cool! Thanks for sharing. There are a lot of coda waves. Are the coda generated by the 3D velocity structure near the source? One impression I have after analyzing the seismogram of this earthquake is that it is more complicated than normal.

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Reposted by Baoning Wu

#shakemovie simulation - Venezuela Mw7.5 event using the USGS finite-fault solution #specfem3d

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Hi Edwin, just in case you haven’t seen (you probably have), do you think your structural complexity explanation could be related to the complex fault geometry around that “gap” shown in this screenshot? It is from Gabriela Quintana Sánchez on LinkedIn. @faultydata.bsky.social

But these are just my thoughts, let me know what you think of it. It is a confusing situation but I feel that we could learn a lot from it.

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Third, two events’ waveforms overlap and the duration of total P wave train is long, but not abnormally long. So although there may be some slow down of the rupture. There is likely no a completely stop and restart of the rupture. Scientifically, I think a single event may be a better description.

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And second, when I go look at back-projection results, finite fault, and InSAR results, I would say this is one event. There are probably two stand-alone high-slip/radiation energy patches, but we see those in other earthquakes as well, which are mostly characterized as one event.

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Yes, I agree. The scientific question is what I’ve been following in the past two days. There is some issue with the two events description. First, when I go look at the waveforms where the USGS report seeing a pick for the second M7.5 event, It is definitely imaginable, but they are not clear.

Made a first-motion focal mechanism for the M7.2 Venezuela earthquake. Seems consistent with the initial rupture fault shown by InSAR.

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So to clarify, my “Seems like a normal SINGLE event with multiple asperities” statement is not solely based on this Peking University finite fault model. And I am not saying this model is correct 100%. But this is another evidence that is consistent with the multi-asperity picture to 1st order.

Thank you for explaining Morgan. I should be more careful in saying what I said. The statement about multi asperity in a single rupture is a synthesis after I seeing several other dataset and analysis from multiple groups, including finite fault, back-projection, C and L band InSAR. aftershocks.

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Preliminary finite fault inversion results by Yuhe Liu at Peking University pku-geophysics-source.group/htmls/202606... Seems like a normal SINGLE event with multiple asperities.

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Harold Tobin @haroldtobin.bsky.social · 27/06/2026

You explained well, Harold. Thanks for doing this for NBC. The "two-event" story is confusing.

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Reposted by Baoning Wu

An explanatory article from @evanbush.bsky.social at NBC News about the Venezuela earthquake(s). www.nbcnews.com/science/eart... ⚒️

Screenshot of text from the article reading: “Tobin said scientists are still weighing whether Wednesday’s sequence was indeed a doublet, though the USGS described it as such.

“It’s actually a subject of lots of discussion right now among seismologists about whether to call it two earthquakes or one earthquake with multiple phases or pulses of energy,” Tobin said, adding that the debate was a little semantic.”

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added magnitude - circle size correspondence.

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A replot of the latest aftershock locations from FUNVISIS (Jun-26 night, California). It seems that there is a gap between the east rupture and the west rupture. One needs a Python script to download the catalog, using the link that the browser uses. www.funvisis.gob.ve/monitor.html

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We may actually test that! I think the InSAR data should have enough resolution to see depth segmentation, right?

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These are useful information. Thanks for sharing, Brandon.