The Trembling Earth

now at

Tag Archives: san francisco

San Francisco 1906 + Today

Shawn Clover is back with a second installment of “The Earthquake Blend,” photo mashups from 1906 quake aftermath and today.

Photographer Shawn Clover, whose clever and chilling project “The Earthquake Blend” I’ve posted about before, has expanded the project with a second installment. Shawn describes the delay, explaining the exacting standards he strives for when recreating the photos. His perfectionism regarding vantage, lighting, and lack of new obstructions is what makes the photography so chilling. As in Part I, the juxtaposition of modern life in SF with scenes of the same locations just a few generations before presents a really eye-opening way of viewing earthquake risk, and bringing the threat to life. These photographs could easily constitute a quake awareness campaign throughout the city.

1906 + Today – The Earthquake Blend: Part II

Have a look through his second set of photo blends. They’re in turn amusing and terrifying. Brilliant work, Shawn.

Hat tip to Christoph Grützner of Paleoseismicity for bringing this to my attention


Fantastic Cal Academy Earthquake exhibit

Earlier this month the California Academy of Sciences–the superb science museum in San Francisco’s Golden Gate Park that efficiently and gracefully combines a natural history museum, science museum, aquarium, zoo/rain forest biodome, and immersive planetarium dome, all under one prairie-covered roof–unveiled its summer 2012 exhibit all about earthquakes.

The exhibit, titled EarthquakeLife on a Dynamic Planet, premiered on May 25, so naturally I was among the first in line at the museum’s Thursday evening 21+ “Nightlife” event the following week. Let me preface the review of this exhibit by saying that the weekly Nightlife event is absolutely brilliant. I could go on for a while about how much I admire the museum for engaging San Francisco’s intellectually and culturally curious population by revamping the museum-going experience with drinks and a DJ, and based on both its regular attendance and its critical acclaim I’m clearly not the only one. If you’re in the area or are ever travelling through on a Thursday evening, this is an absolute must.

Independent of the cocktails and dance music, the Earthquake exhibit is totally a blast, chock full of engaging interactive displays and invaluable quake education. With the wide array of purposes the Cal Academy serves, it certainly has mastered the concise exhibition of fundamental information. The exhibit races you through minerals, rocks, Earth structure, and plate tectonics–all with very touchable displays and materials–then gives a quick intro to global seismology with a circular digital touch display of Earth’s cross section upon which you can induce earthquakes to watch their waves bounce around inside the planet. A layman’s introduction to how and why earthquakes happen, just like that.

There-when-you-need-it wallet sized quake survival checklist from the Cal Academy

Next the exhibit gets right down to the practical essentials for its local attendees: how to prepare for and survive an earthquake. There are plenty of informational materials for the taking, including a wallet-sized reference card explaining what to have in your emergency kit and what to check for after an earthquake. The most effective display in the whole exhibit is the glass case containing all the essential components of an earthquake kit. To me this is an extraordinary way of conveying just how easy a quake kit is to put together because it gives visual reference for the amounts, sizes, and types of items that a kit should include. Seeing the objects laid out and the modest bin that they would fit in gave me a much more intuitive sense and helpful reference than a checklist ever has.

The biggest draw of the exhibit is unsurprisingly the earthquake simulator. At a crowded event the line may be daunting as only a few people are let in at a time for the ~3 minute experience, but who doesn’t love a good ride, and one with educational value? The premise is smart and relevant. They’ve outfitted a small Victorian living room with shelves, china, books, and light fixtures, and a window digitally overlooking the city. The narrator conveys details about the setting and characteristics of San Francisco’s two most noteworthy historic quakes, and hydraulics put you through them in an immersive and illuminating experience. At the very least it serves as a reminder for tremor-jaded San Franciscans what the Big Ones were like.

My favorite part, and imho the main reason to check out this exhibit, is the new planetarium show.

The super high-tech Morrison Planetarium projection dome has been repurposed for the time being from space to the Earth’s interior.

Produced entirely in-house, it’s titled Earthquake, Evidence of a Restless Planet, and has breathtaking visuals, a great soundtrack, and an impeccable script. Sweeping vistas and maps illuminate the geography of quakes around the bay area and around the world, and expert visualizations of real earthquake computer simulations bring modern research to life. The real strength of the documentary is how it ties global tectonics in to local relevance, including the risk and history of life in the bay area. It also emphasizes the profound connection between the forces that cause earthquakes and features of the planet that have enabled the evolution of humanity and the development of civilization. You just must go see it. It also includes a super humbling re-creation of the 1906 earthquake from the center of Market Street, and a brilliant little live interlude to get you up to speed on current seismicity. I adore planetarium shows, and this one is the best I’ve ever seen (although I may be biased toward the subject matter). Watch the trailer below, and tell me you don’t want to sit back and go soaring through these smartly illustrated lessons.

Earthquake, Evidence of a Restless Planet – Trailer

I hardly have the time or space to say all the good things I want to about this exhibit, so let me simply conclude by telling you you have to go see it, and let it speak for itself. The exhibit doesn’t take much time to peruse, but you can’t miss the planetarium show. I’ll be going back again, and I’ll be trying to buy the DVD of this show once I can. If you live in Northern California you have no excuse. If you live a bit farther away… you barely have an excuse.

Has anyone seen it yet? What did you think?

Earthquake photo mash-ups

San Francisco-based photographer Shawn Clover came up with a creative project: not only did he re-create classic photos of the 1906 earthquake’s destruction from the same vantage points as the original shots, but he’s blended the old and new together in surreal, oddly amusing, and moderately alarming photo stitches.

"Two girls stand before the partially destroyed Sharon Building in Golden Gate Park while students work on their art projects inside." Photograph blend by Shawn Clover. More can be found at

From the photographer’s website:

Where was the exact spot the photographer stood? What was the equivalent focal length of his camera’s lens combined with the film medium? How high off the ground was the camera? Where was the sun in the sky? Everything needs to be precise when layering two photos on top of each other.

Have a look at the whole collection:

Shawn Clover – The Earthquake Blend

The fascinating perspectives capturing the destroyed “then” and the recovered “now” would make a superb earthquake awareness campaign, don’t you think?

Urban Planning for Earthquakes – Safe Enough to Stay

SPUR, the imaginatively abbreviated San Francisco Planning and Urban Research Association, released a report in February outlining suggestions for San Francisco to cope with its inevitable destructive quakes. The report results from consultation with experts in relevant fields and agencies from the USGS and CalEMA to _________

105th Anniversary of SF’s 1906 quake

5:12 a.m. PDT this morning marked the 105-year anniversary of “the San Francisco earthquake,” the >400 km rupture of the northern San Andreas fault that began just offshore and propagated along the fault in both directions for several minutes, all the while churning and twisting the blossoming city above it.

Maximum shaking intensity as a result of the 1906 earthquake: the results of a large concerted effort by the USGS and several California universities to simulate major earthquake ruptures throughout the state

It’s helpful to take a moment and reflect upon the reality of the event. I get the impression that such high-profile events lose their meaning as we talk so commonly about them. “The 1906 quake” is surely a part of the California lexicon, if not the country or world, however it still stuns me to realize that this event did happen. Just a century ago the gleaming city of San Francisco was shaken to its core and burned even further. We have come a long way (basically the whole way) in understanding earthquakes since then, and we now construct buildings with mitigation of earthquake risk in mind, but in America we have yet to be tested by another such earthquake so near a huge population center.

To help transcribe the impact of that turn-of-the-last-century event into modern consciousness, my friend John McDaris among a group at Carleton College’s Science Education Resource Center compiled an awesome array of informative and illustrative resources for the quake’s centennial 5 years ago. These include photos, videos, maps, and–most importantly–animations. I encourage eye-opening perusal of all of them, but especially the animations of modern structures subjected to the shaking of the 1906 earthquake.

An evocative screenshot from a simulation of the Golden Gate Bridge as it would have been shaken by the actual 1906 earthquake. Fortunately the display is exaggerated 100 times for illustration

Have at it! Happy anniversary.

[Update: 4/18/11 3:33pm] In an amusing little fluke of nature (or is it? –it is.) San Francisco had a nice little 3.4 jolt today, centered squarely within the San Andreas fault zone just south of the city. Mother Nature’s tip-o-the-hat to all our commemorations, if you want to think of it that way. To my utter disappointment it didn’t ripple the ground quite hard enough to make it rattle Davis, but plenty o’ San Franciscans got a mid-day jostling.

USGS "shakemap" showing instrumentally recorded shaking amplitude during this afternoon

Don’t make too much of this; M3-4 earthquakes are par for the course in the Bay Area: just as likely to occur any other day. Plenty more have happened not on major anniversaries.

Footage of the March 11 tsunami around the Pacific

Plenty of news organizations have been collecting the extensive footage of last week’s tsunami generated by the M8.9 earthquake in Japan, so following along with them is a great way to keep up with the utterly humbling images from the interface between humanity and this planet’s powerful nature.

In particular the BBC has compilations of video from Japan, CNN has a scary view, and the L.A. Times has some footage from the California coast.

A good place to start is with the BBC’s superb explanatory video describing how tsunamis form. Despite the ocean-wide impact of Friday’s tsunami ($50 million in damage along even the CA coast alone), the risk that the U.S. faces from a locally-generated tsunami varies depending on where you live. In particular, although the entire west coast is a tectonic plate boundary, only the northern portion of it is a subduction zone, capable of producing the huge displacements of the seafloor that spawn tsunamis. An L.A. Times article begins to explain that SoCal’s earthquakes don’t pose a tsunami threat.

Here are a couple of humbling tsunami videos from Japan that I haven’t seen widely circulated on the major English news networks. In each of these the incessant and ever-increasing influx of water is almost unbearable to watch and gives a clear sense of the power behind this natural phenomenon.

You can find the other videos here and in this overwhelming film posted on facebook.

Our plight here on the west coast of the U.S. pales in comparison to the utter destruction Japan is facing, but footage of the surge coming ashore in California and Oregon serves as an eye-opening reminder of the tsunami’s power. In this beautiful video we see the surge in sea level coursing through San Francisco Bay toward the coast of Berkeley.

In that video the incoming water has slowed and risen into an elegant series of waves, which crash ashore onto an exposed beach. The waves immediately inundate the shoreline, revealing the elevated sea level driving them. You’ll also notice sharp waves reflected from the shore, crossing the incoming waves almost perpendicularly. Great illustration of constructive and destructive interference.

The tsunami surges into San Francisco Bay on the morning of March 11. The bay bridge and hilly SF skyline are visible in the background. Photographed by Steven Winter. Thanks to for highlighting it.

There are many more videos of the wave entering San Francisco Bay, as well as some great time lapse views of other coastal areas, and an impressive shot of one surge barreling through Santa Cruz Harbor that clearly illustrates how so much damage was done by a relatively small wave.

Tidal gauge stations and buoys are another great way to view the effects of the wave all around the Pacific. In Japan, tide gauges are still recording rapidly oscillating water levels along the shore. These hardly compare to the water levels associated with the initial onset of the tsunami, but the Pacific ocean is still clearly in much more tumult than it was in the relaxed days before the quake.

Tidal gauging station from the central coast of Japan on March 11, recording the onset of the tsunami. The green line below is the "risidual," which is effectively the difference between the water level and the expected tide.

Check out other tidal records from Japan yourself:

Thanks to friends, relatives, and colleagues alike for directing my attention to some of these amazing perspectives.

%d bloggers like this: