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Just say in’ I can take this metaphor really far& I’ve got more puppy pile .gifs if anyone has follow-up questions.
Dirty secret:
We can only identify forequakes (smaller earlier quakes) retroactively.
It’s like a puppy kicks another, who then gets up and disturbs the rest of the pack. It’s all the same mechanisms, but we name the biggest movement as the main quake.
We can only identify forequakes (smaller earlier quakes) retroactively.
It’s like a puppy kicks another, who then gets up and disturbs the rest of the pack. It’s all the same mechanisms, but we name the biggest movement as the main quake.
Different geologic settings have different types of earthquakes, just like job demands led to puppy breeds with distinct characteristics.
Environment strongly influences what types of characteristics you’ll see. Even then, individuals can surprise us.
Environment strongly influences what types of characteristics you’ll see. Even then, individuals can surprise us.
Yes! At some point, with fewer and fewer fidgets, everything zonks into a nap.
Aftershocks decrease exponentially in both frequency & intensity — smaller puppy-wriggles to adjust less often.
Until the stress shifts & the pile awakens to start again.
Aftershocks decrease exponentially in both frequency & intensity — smaller puppy-wriggles to adjust less often.
Until the stress shifts & the pile awakens to start again.
Bonus:
The bigger the quake, the bigger the aftershock sequence. An M8 will have M7 aftershocks shortly after, but might still be triggering M3s a year later!
Like if a super-energetic puppy races by, you know the whole pack is riled up for a while.
The bigger the quake, the bigger the aftershock sequence. An M8 will have M7 aftershocks shortly after, but might still be triggering M3s a year later!
Like if a super-energetic puppy races by, you know the whole pack is riled up for a while.
Seismic waves as puppies:
P-waves: Alapaha, burly but surprisingly quick. These pressure waves push through it all & show up first.
S-waves: Dachshund, wriggly & cant swim. These shear waves scamper in second, but can’t get through the liquid outer core.
P-waves: Alapaha, burly but surprisingly quick. These pressure waves push through it all & show up first.
S-waves: Dachshund, wriggly & cant swim. These shear waves scamper in second, but can’t get through the liquid outer core.
Note:
Like S-waves trigger P-waves at mantel-core boundary, dachshunds will find creative ways to interact with water so you never forget them.
Like S-waves trigger P-waves at mantel-core boundary, dachshunds will find creative ways to interact with water so you never forget them.
Surface waves are the high-energy breeds that romp big.
Rayleigh: Shiba Inu. Unmistakable, stylish, and way too at peace with being weird. Rolls like the ocean.
Love: Huskies. Extremely precise movement, extreme destruction if you don’t pay attention & plan ahead.
Rayleigh: Shiba Inu. Unmistakable, stylish, and way too at peace with being weird. Rolls like the ocean.
Love: Huskies. Extremely precise movement, extreme destruction if you don’t pay attention & plan ahead.
We don’t know subsurface geology in perfect detail. We have a pretty good idea of what’s happening, but sometimes we don’t know about a fault until it moves. (1994 Northridge was on a previously-hidden fault.)
You’ve seen puppies. You know how this happens.
You’ve seen puppies. You know how this happens.
That same inherent uncertainty of reality is what makes forecasting tricky.
Part of why we can’t predict exactly where/when a quake will happen is because we don’t know if a puppy will nudge a squishy belly vs kick a sensitive nose, or how much stress it takes to break.
Part of why we can’t predict exactly where/when a quake will happen is because we don’t know if a puppy will nudge a squishy belly vs kick a sensitive nose, or how much stress it takes to break.
Seismic engineering, shakeout drills, early warning systems, and kits & plans are important for the same reason training dogs is important:
That much energy has a lot of destructive potential, with a scary ability to cause harm. Preparation is essential.
That much energy has a lot of destructive potential, with a scary ability to cause harm. Preparation is essential.
Getting at the maximum extent of earthquake influence means digging into white lies of simplification.
How far is too far? What is negligible? What is a fault, exactly?
This is going to take a lot of puppies. Ready to unlearn & dig deeper?
How far is too far? What is negligible? What is a fault, exactly?
This is going to take a lot of puppies. Ready to unlearn & dig deeper?
A fault is a weak point where rock breaks. but... it can also be a fault zone, a whole area of weakness. Technically 2 terms, but we’re sloppy about vocab.
Kinda like when you’ve got individual puppies, but they’re all together doing pretty much the same thing.
Kinda like when you’ve got individual puppies, but they’re all together doing pretty much the same thing.
Each puppy (& fault) is independent, but when they’re nearby you’re not really surprised when they feed off each other.
The San Andreas Fault is actually like a bajillion segments all tagged together — a run of puppies. Any could do their own thing, but they totally interact.
The San Andreas Fault is actually like a bajillion segments all tagged together — a run of puppies. Any could do their own thing, but they totally interact.
Instead of shuffling, let’s think of earthquakes as a howl. Tectonic setting & energy impact aftershocks.
A wee puppy howl might set off the household pack, but not the whole neighbourhood. But a full-grown aroo from the mountains? That might start the whole forest singing.
A wee puppy howl might set off the household pack, but not the whole neighbourhood. But a full-grown aroo from the mountains? That might start the whole forest singing.
Coulomb stress transfer is really complicated & involves a lot of factors we can only estimate indirectly. The uncertainty is enormous.
Wee pup gave a howl & has packmates nearby, but everyone else stayed silent. For now. But why? & for how long?
Wee pup gave a howl & has packmates nearby, but everyone else stayed silent. For now. But why? & for how long?
How close is close enough?
It depends.
For howling, the same room for sure, maybe a neighbourhood, but def not across the state.
For quake stress, within a few km for sure, maybe a few hundred km for big fault systems & long times, but not a continent.
It depends.
For howling, the same room for sure, maybe a neighbourhood, but def not across the state.
For quake stress, within a few km for sure, maybe a few hundred km for big fault systems & long times, but not a continent.
Things that make me proud:
None of the (many!) geophysicists who chill with me on Twitter chimed in with objections or corrections to my Earthquakes As Puppies explainer.
I passed my live peer review!
(moar questions = moar pups)
None of the (many!) geophysicists who chill with me on Twitter chimed in with objections or corrections to my Earthquakes As Puppies explainer.
I passed my live peer review!
(moar questions = moar pups)
Any time fluid is injected into the ground (fracking, wastewater), that mix of adding liquid to decrease friction while also adding stress is like fresh food in bowl on a freshly-polished floor.
Puppies you didn’t know you had will come running!
Puppies you didn’t know you had will come running!
The vast majority of earthquakes at at plate boundaries, just like most pups live with dog-lovers.
But sometimes we get intraplate quakes from relic faults (inherited pup), plate buckling (your heart was stolen by THAT pup), or human activity (puppy ads).
But sometimes we get intraplate quakes from relic faults (inherited pup), plate buckling (your heart was stolen by THAT pup), or human activity (puppy ads).
