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SeismoDome: Shaking Up Seismology Through Sight + Sound

What better way to dive into seismology than to suddenly find yourself in the Earth’s core gazing up at its shaking crust? To see seismic waves bouncing back and forth through the center of the Earth and spreading along its surface? To hear and feel the rich and rapidfire rattling as shocks travel around the world?

In 2005, What better way to dive into seismology than to suddenly find yourself in the Earth’s core gazing up at its shaking crust? To see seismic waves bouncing back and forth through the center of the Earth and spreading along its surface? To hear and feel the rich and rapidfire rattling as shocks travel around the world?

In 2005, geophysicist Dr. Ben Holtzman + sound designer Jason Candler teamed up to create the Seismic Sound Lab, providing an immersive multisensory experience of the Earth’s quaking. The project most recently culminated in SeismoDome—an epic sight + sound journey through five earthquakes, as experienced from way out in space to deep inside the Earth—which premiered at the famed Hayden Planetarium. The initial seed for this undertaking was planted in part by the devastating Sumatra–Andaman earthquake, the third largest earthquake ever recorded, directly hitting 14 countries and triggering earthquakes as far away as Alaska. Holtzman, who studies rock mechanics at Lamont-Doherty Earth Observatory, recalls:

It was the first time in my life that the research I was involved with had any implications for humans. I started to get much more interested in communicating seismology, and the scale of Earth science, to the public.

The Earth’s outer layer is fractured into an array of tectonic plates that are in steady slow motion as a result of the constant convection of the mantle—the molten rocky layer that lies beneath the surface. Mantle convection [a process similar to boiling] creates a current that forces some plates to push together as others pull apart at boundaries dubbed faults. As two or more of these plates interlock and push against each other, energy builds and concentrates along the fault line. Eventually, the fault reaches its breaking point, at which point the plates suddenly move or lurch under the stress, releasing all that pent up energy in the form of seismic waves that radiate out from the source.

left: The Earth’s surface is broken up into tectonic plates, which are constantly shifting due to mantle convection beneath the crust. right: Mantle convection is the result of mantle rocks melting and cooling due to the drastic temperature difference between the Earth’s piping hot core [~ 4,030 °C] and its far cooler crust [200 °C].

Every day, the Earth is rattled by several hundred nearly imperceptible earthquakes, ranking magnitude 2 or lower on the Richter scale. While we can’t always feel the tremors beneath our feet, scientists have long tracked these disturbances using instruments known as seismometers, which measure ground motion over time. Arrays of seismometers have been strategically placed around the globe, recording a steady stream of measurements that give us insights into how seismic waves behave. This vibrational information is the raw material for Candler and Holtzman’s quaky compositions.

While science tends to privilege sight over our other senses—relying on graphical representations and illustrated models to visualize data and convince an audience of a given result—we experience the world with more than just our eyes. Consequently, data visualization comes with certain limitations. According to Holtzman: “Our eyes have excellent resolution in gradients of light and color, and much worse resolution in time. Conversely, while our ears don’t have great resolution in pitch, they have really good resolution in time.” This sensory tradeoff lies at the heart of SeismoDome’s special power. By marrying sight and sound, Holtzman and Candler have crafted an utterly rich and multi-layered experience of the data at hand. Holtzman notes:

We would give these spiels, trying to find the right words to say that these are waves traveling around the Earth, and that sense of motion you’re getting is the result of these waves moving from one seismometer to another. But when we finally got the sound synched with the visuals, we suddenly found that we didn’t have to explain anything. The sights and sounds just said it all for us.

The team employs a multi-channel circle of speakers to craft a well-rounded sonic experience, feeding data from seismic stations around the world into each speaker. The result is a spatially accurate ring of sound that allows your ears to trace the waves as they propagate along and through the Earth. To complement the sounds, they use that same set of data to create visual models of seismic activity. Click the video below for just one look at the result.

SeismoDome rendering of seismic data from California recorded over six years, conveying the magnitude of these ubiquitous events sonically through tone + duration and visually through size + color gradation.

Depending on where in the world you live, earthquakes take on drastically different significance. Here in New York, our planet’s rumblings hardly cross my consciousness, whereas just across the country, entire cities were built with earthquake resiliency heavily in mind. Nevertheless, the above video gives you an immediate appreciation—a real gut feeling—that earthquakes shake us all. In addition to the surface waves that travel along the Earth’s surface, seismic waves can traverse the Earth’s core, bouncing back and forth through its interior in the form of body waves that can reach the opposite side of the world in as fast as a half hour! Below, you can see and hear the rolling of the waves as they echo through the globe as a result of the 2011 Tohoku earthquake.

The video above visually simulates body + surface wave propagation resulting from the 2011 Tohoku earthquake, while using scaled seismographic data to create those real, rumbling sounds.

In addition to the Tohoku and Sumatran earthquakes, SeismoDome systematically steps you through three other earthquakes that have occurred over the last decade: the 2010 Haitian earthquake, the 2013 Kamchatka earthquake, and the 2006 Parkfield earthquake. To develop a multidimensional appreciation for each catastrophe, the SeismoDome team has translated data from a variety of vantage points. Far out in space, you can watch the waves ricochet through the Earth’s core, the sounds less pronounced, like a far-off thundering. But deep in the belly of the planet, the sounds engulf you, rattling your seat as your eyes and ears trace the trajectory of the seismic disturbances. And then, far on the opposite side of the planet, you stare in amazement as you see and hear the blips and beeps that correspond to far off, ground-breaking devastation. “We wanted to put you a little more in touch with the planet, so you realize it’s got a mind of its own. It’ll quake wherever and whenever the hell it wants to,” Candler remarks, to which Holtzman adds: “It’s a real reminder of the scale of us compared to something like an earthquake. I like doing it in the planetarium for that reason—it shakes you out of your usual sense of time and space.”

As I was sitting in that planetarium, literally being shaken by all the data, I couldn’t help but wonder at the fact that despite the dramatic scale of this geological phenomenon—despite the enormous body of ever-updating + widely-accessible data—seismology still faces a great many open questions, chief among them being: How can we come to predict when and where an earthquake will occur? Holtzman explains:

I like the weather analogy. Weather is a very complex interaction of many different systems, but we can measure everything–wind speed, temperature, pressure–which we put into predictive models. But we still can’t predict the weather, like when exactly it will rain. With earthquakes, however, the measurements aren’t very direct and they’re not at the right time and length scale. But even still, that analogy is a little ill-posed because with earthquakes, the scale you’re interested in is not something like whether it’s going to rain. Instead, you want to predict where the individual rain drops are going to hit, which is impossible.

It’s challenges like this—the big, looming questions—that send out ripples filled with smaller questions, which make up all those lines of inquiry that ultimately coalesce into seismology: questions about our Earth’s internal composition, about the dynamics of wave propagation, about our own role in altering these larger-than-us geological systems. All the complexity and nuance of the problem is reflected in SeismoDome’s sounds—in the crazy ebb and flow of those data-triggered pops and bleeps and booms.

Illuminating these gaps in our understanding is, to me, what cultivates a certain sense of excitement and awe, rallying curious minds behind a given problem as they develop an appreciation for the magnitude of the mysteries science endeavors to solve. Personally, it’s these sorts of open questions that drove me to biology, and have since sent me down several science-y rabbit holes, including the seismological cave I emerged from just now to write this. Perhaps this is cheesy, but it’s almost like the emotional equivalent to the sentiment behind John F. Kennedy’s famous “ask not what your country can do for you—ask what you can do for your country” … except with science.

So with that in mind, I was extremely excited to hear what the Seismic Sound Lab has in store. In the spirit of learning through tinkering, the team is currently developing a series of portable prototypes to allow you to create your own interactive SeismoDome microenvironment! Holtzman shares:

The format that most interests me is Exploratorium-type exhibits where you play with the data. Doing these shows is great and fun and exciting, but I think people learn much more when they sit there and play with the data, changing it to figure out why something sounds different. They don’t realize what they’re learning as they’re doing it, but it’s those experiments that stick with them.

To learn more about the Seismic Sound Lab and stay in the loop, be sure to check out seismicsoundlab.org, and for a neat guide to how SeismoDome was created, visit the Sounds of Seismology!