3d plot of earthquakes in Ferrara-Modena-Bologna

The earthquakes that recently hit my hometown and region triggered a natural sequence of minor quakes. Thanks to the available data, I was able to plot the 3d representation of the ipocenters. Red points represent all the quakes from the start of the seismic sequence to the 3rd of June. Points in purple represent particularly strong quakes (5.0 or higher). Blue squares represent cities. I suggest to enable the 720p version.

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Earthquake shakes my city

The readers of my blog will certainly know that I am extremely responsive to the earthquakes and the destruction they leave behind. I covered the Japanese quake in rather detail, exploring the seismic activity as it developed. The Japanese quake was deeply emotional for me, and I lived in Tokyo for just one year. This time it hit my city, my home town.

Ferrara is a rather small city in Italy, sitting in the Pianura Padana, one of the very few flat areas in Italy. It’s a nice city with a nice university and a surrounding countryside focusing on rural traditions that are hundred years old. Due to the proximity to the Po river, the major source of danger are floods. Our city, and its inhabitants are deeply unprepared for a quake, both psychologically and technically. The last major quake in the area dates back to 1570, where it contributed to the decline of the city.

The one happened a few days ago is a major quake. With 6.0 Richter, it’s the maximum you can get from the local geological situation. The Po valley is actually hiding, under a pile of sediments deployed by the river, the interaction between the Apennins and the Alps. The quake that hit the city arises from this interaction. Damages are considerable, in particular in the West side of the province, close to the epicenter. Seven people lost their lives. A lot of buildings, churches and towers often dating back to the middle ages collapsed. Even a part of Ferrara’s iconic castle collapsed. The loss of the historical heritage is immense. The loss for the people’s houses are atrocious and hit a population which is among the oldest in Italy. The psychological effect has been considerable, but people organized, with courage, equilibrium and commitment.

Now more than ever, I ask anyone willing to provide support to perform a donation at the public donation fund from the newspaper Il Resto del Carlino and TG5.

A translation for the fields:

  • Intestatario: account owner
  • Banca: Bank
  • Causale: reason for transfer

Apparently there is no BIC available. I will update this post if I find more information about it. I will try to perform a donation tomorrow, and I will certainly have to find it.

Edit: Apparently any BIC for the bank will work. Your online banking should propose the correct one depending on the bank name (at least mine does). I decided skip the donation, and instead I am organizing to go there and provide some help to the locals.

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SeisMac and Quake-Catcher Network – turn your mac into a seismograph

Occasionally, I get to find very interesting scientific apps for the Mac. In light of the recent events, SeisMac is definitely one of those. While not technically useful for the general public, it is a very important application for research.

All Mac laptops include the so-called Sudden Motion Sensor, a Micromechanical system (MEMS) accelerometer. This sensor is a very cheap integrated circuit which can be found in iPhones, iPod touch, the WiiMote, and many others gadgets. In the case of laptops, its main purpose is to park the hard drive head in case of a sudden drop, reducing the chance of damage to hard disk platters due to impact with the reading head. The sensor can however be queried and used for many other applications, from the facetious (like LiquidMac) to the more serious, like SeisMac. The idea is to use the Sudden Motion Sensor to detect earthquakes, effectively converting your laptop in a seismometer. It is interesting to see how sensitive the Sudden Motion Sensor can be. This is a tracking of my laptop with SeisMac

SeisMac image

The nervous, black oscillations you see on the left hand side are produced by a fan on my table, which I then removed. As you can see, these oscillations are uniform on the x, y and z axes. The single spike along the z axis you see in the center it’s me doing a touchpad click to take a screenshot, and the series of strong impulses on the right it’s again me, typing the filename. Don’t be deceived by the stronger than usual gravity. I never calibrated the reading, so the absolute values can be wrong.

SeisMac is great, and you can configure its sensitivity to disregard human-generated events and catch the big deal when the quake strikes, but it does not beat another similar program, with a very interesting distributed project behind it: the Quake Catcher Network. The idea is simple, but very powerful: laptops and desktops volunteering to be part of the network constantly collect seismic data through the Motion Sensor, and alert a central server of any movement. If the laptop is moved, hit, or a local, non-seismic event occurs (such as a truck passing by), the signal will be considered by the central server as spurious due to its locality. However, if multiple unrelated laptops feel the same event, the server will validate it as an actual quake. Knowing the position of each laptop it is possible to obtain the intensity of the quake at each location, the speed of propagation, and the kind of oscillation. All these data provide precious details not only on the quake itself, but also on the terrain and the buildings, a very important dataset to improve prevention and emergency response.

Additional Links

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Plotting seismic events in Japan in 2D and 3D

I just saw this very interesting and shocking movie reporting the quakes rattling Japan from 9th to 14th of March.

The amount of events after the big one, at 1:17, is devastating. I wanted to see more, adding the third dimension. I tinkered with wget, bash, gnuplot and ffmpeg to produce this less visually appealing but scientifically important data representation

What you see is the hypocenter (latitude, longitude and depth) of each quake from the 6th to 17th of March. Data were gathered from the Japan Meteorological Agency web pages for the purpose of personal use and research. Red points are surface quakes (from 0 to -20 km), green are medium depth (-30 to -50) and blue are deep quakes (-60 to -80). You can clearly see the very steep subduction zone as a sharp feature digging into the Earth crust. It’s a real tragedy we have to pay such high price associated to these data, but these data from previous events are the ones that allowed many lives to be saved today.

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The Japanese quake

Yesterday around 14.30 a big quake hit the Sendai area in Japan, followed by a tsunami and a contiguous stream of additional shocks. I immediately contacted friends in Tokyo and they are all fine. Transportation in Tokyo is interrupted, and so is communication. I don’t know any more details. I just have news from a friend.

Plates under Japan. Tokyo is marked with a red dot.

Tokyo and the whole of Japan lays in the so called pacific ring of fire, an area of violent seismic and vulcanic activity due to the pacific tectonic plate subducting with the continental plates on the american and asian sides. The very existence of Japan is due to this subduction, creating the arched set of islands as a consequence of the arising volcanic activity. Tokyo, with a grand total population of 30 millions in the metropolitan area, sits right on a triple trench junction, basically a ticking bomb with an historical average timer of approx. 100 years. Unfortunately this quake is unlikely to reset the timer. The Tokai zone, where this triple junction develops, is further South. Japan as a whole sits on a subduction-powered ticking bomb, and you are reminded often about it. In the year I spent in Tokyo, I experienced a dozen quakes strong enough to be felt.

I could have been there now if I continued my employment at NII. Words fail me. It’s a place I called home for a year, a place I learned to know somehow, and now it has changed completely. Places I visited are now under water, and landmarks I used to see every day are scarred. I am deeply, deeply sad. I know that the people of Japan will shrug this tragedy away with their restless efficiency and poised philosophy, and I wish them all the best.

My final remark wants to remember that it is due to the Japanese productivity and dedication, the advanced planning and organization, the technological level of engineering and the compliance to building regulation that hundred of thousands of lives were saved today. Engineers and builders are the real heroes in this catastrophe, years before it struck. Hands that do are those which make life better.

Edit: Please donate to the Japanese Red Cross today, through google. They need your help. The situation is getting worse and worse.

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Large quake occurs near Chile.

A magnitude 8.8 quake occurred in Chile. A tsunami warning has been issued. Very good details, and a map of the predicted height of the tsunami across all the pacific can be found at Phil Plait’s blog.

Apparently, Japan is not concerned about the Tsunami, which should hit around 3 AM GMT (12AM Japanese time). The advisories from the Japanese meteo/quake agency has no information about any critical measures to be taken.

Yesterday, a weaker but still relevant quake hit the island of Okinawa, in the south of the Japanese Archipelago.

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