Rich Briggs

US earthquake safety relies on federal employees’ expertise The US experiences violent earthquakes, but the damage and death toll is much lower than in many countries because of the work of federal seismologists and engineers.

“Earthquakes and the damage they cause are apolitical… we either prepare for future earthquakes or the population eventually pays the price... In the U.S., this preparation hinges in large part on the expertise of scientists and engineers in federal agencies…”

theconversation.com/us-earthquak...

A radar interferogram covering 17.5 to 23.5 degrees north, in Myanmar. Tightly clustered fringes delimit the likely 2025 earthquake rupture zone.

The whole #MyanmarEarthquake rupture in one interferogram! This is three consecutive wide swath frames of ALOS-2 data, provided by JAXA through agreement with NASA. The line-of-sight (LOS) is ~perpendicular to fault strike, so most of what you see is vertical motion at bends and steps of the fault.

USGS Myanmar earthquake remote surface rupture obervations 🔁REFRESH🔁

doi.org/10.5066/P1RY...

Offsets from Sentinel2 and Landsat pixel tracking ➡️ (slip blip at southern end; the rupture that can’t stop won’t stop)

On-fault offsets from high-res imagery ➡️ more detailed fault mapping

Surface ruptures of the Myanmar M7.7 earthquake mapped from space An extremely long rupture is confirmed

⚒️ 🧪

New satellite imaging of the Myanmar earthquake area confirms that the rupture was unusually long: ~500 km.

We discuss the data, the rupture, and the implications, in our latest post.

earthquakeinsights.substack.com/p/surface-ru...

Map of Myanmar area showing sharp color change along the fault running roughly north-south. Red on west side where land moved northward.

NASA JPL ARIA project analysis of data from Copernicus Sentinel-2 optical and Sentinel-1 radar images measured the slip on the Sagaing Fault in Myanmar. Quick preliminary map. More details later. Fault ruptured about 500 km (300 miles) in the magnitude 7.7 […]

[Original post on mastodon.social]

Screenshot of Myanmar M7.7 surface rupture map service

Remote surface rupture observations for the M7.7 2025 Myanmar earthquake - soft rollout!

doi.org/10.5066/P1RY...

Simple fault trace and slip distribution from pixel tracking, high-res from available imagery. Watch for updates!

⚒️ USGS and collaborators effort led by @nadinegrr.bsky.social 🙏

People working on laptops

Friday afternoon imagery session, missing @nadinegrr.bsky.social who was busy working the phones

Heartfelt thanks to the USGS crew and others (especially @wangyu-1979.bsky.social) for working hard behind the scenes the last few days to confirm the loooong Myanmar rupture for the response products. Surface rupture imagery is bonkers. What a tragedy for the folks there, sending ♥️💔♥️

Boom what a team 🤜🏼🤛🏼

Magical INSAR led us to rupture from the M5.8 Parker Butte Nevada earthquake. 1.5 km of surface rupture, right lateral, max offsets 2-5 cm, on NNW plane. Conjugate to NE trending aftershocks.

Curious about what the NVseismolab gets up to? Check out this video and follow us on Instagram for more behind the scenes action! 👉 www.instagram.com/share/BAV7Q5...

New trench excavated across the Alpine Fault at Blue Grey River. Definitely reverse dominant at this site. Thanks to @jameslagreca.bsky.social and Liv for their hard work. We were lucky with weather but eventually chased off by torrential rain.

⚒️ Looking for a PhD in numerical modeling about earthquake cycle and surface deformation using Discrete Element Modelling?
Join us at IPGP, open position to start next Fall 2025.
Possibilities of funding for master internship prior to PhD if needed.

For information and application, just email me.

⚒️ If you are puzzled by shallow slip deficit during strike-slip earthquakes, maybe diffuse deformation is part of the answer.
S. Antoine et al. revisited the Ridgecrest earthquake and got ride of almost all of the SSD by better accounting for off fault deformation.
dx.doi.org/10.1029/2024...

Web of Spider-Man comic 1

Ha, keeping with the theme - made me drag this one out

Nice work crew! 🩵🤎Nevada💚💙

SPOILER ALERT: Went out to collect perishable data around yesterday's M5.8 epicentral region. Preliminary results: Nobody feels aftershocks when @faultcreeper.bsky.social is driving. Afternoon frozen slushy river makes for extremely cool co-seismic features (new types? to document!). 1/2

Aftershocks of the 9 Dec 2024 M5.8 extending SE from the original trend

Ok Nevada, don’t start any of this conjugate faulting stuff. Stay chill little bro

Shout out to our field team who worked all night setting up temporary seismic stations near the epicenter of the ML 5.8 earthquake NNE of Yerington so we can better monitor aftershock activity.

Great post! Wabuska . . .ish? The aftershocks currently line up 5+ km south of the scarps mapped by Li et al. But yeah, it’s a complex distributed feature. We didn’t include the lineament in the 2023 NSHM update because of the considerable uncertainties in location, but it’s worth revisiting!

A shaky day for us here in Nevada with a M5.5 earthquake NNE of Yearington at 3:08pm. Did you feel the shaking? Report it here earthquake.usgs.gov/earthquakes/...

Earthquakes in Nevada 9 Dec 2024

USGS event sequence

Cool little blob of preceding seismicity

www.seismo.unr.edu/Earthquake

Oh and USGS has the Event Sequence tool now 🤜🏼🤛🏼 (link is fugly, scroll down at earthquake.usgs.gov/earthquakes/...

Ok cute little Monte Cristo-ish sequence, time to die down 😹

Nice stuff @nvseismolab.bsky.social 🙌🏽👊🏼

Epicenter

Aftershocks

Moment tensor

Nevada doing Nevada things - likely l-l s-s on unmapped NE trending structure near Desert Mtns. Mw 5.5 earthquake.usgs.gov/earthquakes/... Screenshots lol

An exciting PhD opportunity has come up w/ the Ngā Ngaru Wakapuke program in"Understanding earthquake sequences using near- and on-fault
paleoseismology on the western Marlborough Fault System". To work with leading paleoseismologists from VUW (J Howarth) & GNS. Contact k.clark@gns.cri.nz for pdf

Localization and Delocalization During Seismic Slip Seismic slip layers are ∼1 mm−1 cm thick, regardless of temperature, rock type, or depth, balancing heat production and dissipation Thicker earthquake slip layers are possible but cannot be detec...

New paper alert‼️

Prof. Heather Savage (UCSC) and Prof. Christie Rowe (UNR) characterized the size of slipping layers during earthquakes and how this influences the size of earthquake events through heat production and dissipation.

Check it out here: tinyurl.com/8xdj6wut

Tilted rock outcrop, conglomerate

Rock outcrop and lenticular clouds

Closeup rock outcrop and lenticular clouds

Bike and a rock

Rocks and clouds: Paleocene Green Mountain Conglomerate sitting on Paleocene/Upper Cretaceous Denver Formation. Oh and some cute lenticular clouds, and Red Rocks Amphitheater in the distance.

Classic Scott 1972 map: coloscisoc.org/wp-content/u...

I’m not an instructor but in moments of doubt I reach for Robert Stern’s line: “Subduction zones are descending limbs of mantle convection cells and are the dominant physical and chemical system of Earth's interior.” Then I get granular. Good luck and thanks for teaching the next generation!

Yellow lab with a lot of legs

Can confirm

Presumably grabbing a nap in between scarfing on dead things in the woods