If your only exposure to seismologists at work is through film and television, you can be forgiven for thinking they still lay out rolls of paper to examine lines of ink under a magnifying glass. The reality is far more interesting in a field that has eagerly adopted all available technology. A dramatic demonstration of modern earthquake data gathering, processing, and visualization was Tweeted by @IRIS_EPO following a central California quake on July 4th, 2019. In this video can see the quake’s energy propagate across the continental United States in multiple waves of varying speed and intensity. The video is embedded below, but click through to the Twitter thread too as it has a lot more explanation.
The acronym IRIS EPO expands out to Incorporated Research Institutions for Seismology, Education and Public Outreach. We agree with their publicity mission; more people need to know how cool modern seismology is. By combining information from thousands of seismometers, we could see forces that we could not see from any individual location. IRIS makes seismic data available to researchers (or curious data science hackers) in a vast historical database or a real time data stream. Data compilations are presented in several different forms, this particular video is a GMV or Ground Motion Visualization. Significant events like the 4th of July earthquake get their own GMV page where we can see additional details, like the fact this visualization compiled data from 2,132 stations.
If this stirred up interest in seismology, you can join in the fun of networked seismic data. A simple seismograph can be built from quite humble components, but of course there are specially designed chips for the task as well.
Continue reading “Watch Earthquake Roll Across A Continent In Seismograph Visualization Video”
If you’ve ever been in an earthquake you’d assume it would be pretty easy to detect one. If things are shaking, there’s an earthquake. In reality, though, a lot of things can shake a sensitive instrument that is detecting shaking, so — for example — mechanical sensors will produce a lot of false positives. Now, however, you can filter out errant vibrations and reliably detect earthquakes on a chip.
The Rohm BP3901 has two primary features. First, it supposedly eliminates false detections due to things like a heavy truck rumbling by. In addition, while most sensors must be mounted completely flat, the BP3901 has a compensation method for angle which lets you mount it as much as 15 degrees rotated in either direction and still get good results. That’s because the BP3901 is based on the combination of an accelerometer and a microcontroller in one package to detect movement, characterize it based on an algorithm and reacting through an I2C bus and an INT pin.
Rohm suggests you could power the BP3901 for about 5 years with two AA batteries with the example of averaging 10 three-minute wake up events a month. We aren’t sure why we want to detect an earthquake, but we think we do. Imagine a large sensor network sending back real-time data as an earthquake happens — something we saw last year using Raspberry Pi. That project used a Geophone as the detector, which could be replaced by this chip. Rohm plans to have “OEM quantities” for sale next month which we hope means we can get smaller quantities from distributors.
A lot of people spend a lot of time thinking about how to predict earthquakes, as we’ve seen before. Of interest, the ancient Romans may have had a way to deflect earthquakes, so they probably didn’t care as much about detecting them.
For those outside the rocking and rolling of California’s tectonic plate, earthquakes probably don’t come up on a daily basis as a topic of conversation. Regardless, the instrument to measure them is called a seismometer, and it’s entirely possible to build one yourself. [Bob LeDoux] has shared his article on how to build a Fluid Mass Electrolytic Seismometer, and it’s an impressive piece of work.
This is an instrument which works very differently from the typical needle-and-graph type seen in the movies. Fluid is held in a sealed chamber, with a restricted orifice in the center of a tube. The fluid level is monitored at each side of the orifice. When motion occurs, fluid levels change at either side which allows seismic activity to be measured.
Hooked up to some basic analog electronics, in this form, the device only shows instantaneous activity. However, it would be trivial for the skilled maker to hook this up to a datalogging setup to enable measurements to be plotted and stored. The entire project can be built with simple hand tools and a basic PCB, making it highly accessible.
It’s not the first time we’ve seen a seismometer, either – the Raspberry Shake project is a distributed network of sensors running on the Raspberry Pi.
The Raspberry Pi’s goal, at least while it was being designed and built, was to promote computer science education by making it easier to access a working computer. What its low price tag also enabled was a revolution in distributed computing projects (among other things). One of those projects is the Raspberry Shake, a seismograph tool which can record nearby earthquakes.
Of course, the project just uses the Pi as a cost-effective computing solution. It runs custom software, but if you want to set up your own seismograph then you’ll also need some additional hardware. There are different versions of the Raspberry Shake, the simplest using a single Geophone which is a coil and magnet. Vibrations are detected by sensing the electric signal generated by the magnet moving within the coil of wire. Other models increase the count to three Geophones, or add in MEMS accelerometers, you can easily whip one of these up on your own bench.
The entire setup will fit nicely on a coffee table as well, making it much smaller (and cheaper) than a comparable professional seismograph. Once all of the Raspberry Shakes around the world were networked together, it gives an accurate, real-time view of seismic activity anywhere you can imagine. If you’ve ever been interested in geology or just want to see where the latest earthquake was, check out their projects. But you don’t need even a Raspberry Pi to see where the earthquakes are, thanks to a Hackaday Prize entry all you need is a Twitter account.
Thanks to [Rich Cochran] aka [AG6QR] for the tip!
Seismic waves travel through the Earth’s crust at about four kilometers a second. Light travels through fiber at about 200,000 kilometers per second. Taking network lag into account, it’s possible to read a Tweet about an earthquake a few seconds before the shaking starts. This is the concept behind an XKCD strip and a project for the Hackaday Prize.
[Zalmotek]’s Earthquake Validation Gadget is an Internet-connected box designed for those few seconds between asking yourself, ‘is this an earthquake’ and saying, ‘yeah, this is totally an earthquake’. Inside this wall-mounted box is both a sensitive vibration sensor and a microcontroller connected to the Internet. If the vibration sensor goes off, it checks the Internet — the USGS website is a great start, by the way — for any large, local earthquakes. If there’s a possibility that shaking is an earthquake, lights and sirens go off, telling you to take cover.
The idea of an ‘earthquake warning device’ isn’t new. The USGS has a system in place for just this sort of thing. It’s good to see independent researchers working on this, though, and it makes for a great entry to the Hackaday Prize.
Nepal | 25 April 2015 | 11:56 NST
It was a typical day for the 27 million residents of Nepal – a small south Asian country nestled between China and India. Men and women went about their usual routine as they would any other day. Children ran about happily on school playgrounds while their parents earned a living in one of the country’s many industries. None of them could foresee the incredible destruction that would soon strike with no warning. The 7.8 magnitude earthquake shook the country at its core. 9,000 people died that day. How many didn’t have to?
History is riddled with earthquakes and their staggering death tolls. Because many are killed by collapsing infrastructure, even a 60 second warning could save many thousands of lives. Why can’t we do this? Or a better question – why aren’t we doing this? Meet [Micheal Doody], a Reproductive Endocrinologist with a doctorate in physical biochemistry. While he doesn’t exactly have the background needed to pioneer a novel approach to predict earthquakes, he’s off to a good start.
He uses piezoelectric pressure sensors at the heart of the device, but they’re far from the most interesting parts. Three steel balls, each weighing four pounds, are suspended from a central vertical post. Magnets are used to balance the balls 120 degrees apart from each other. They exert a lateral force on the piezo sensors, allowing for any movement of the vertical post to be detected. An Arduino and some amplifiers are used to look at the piezo sensors.
The system is not meant to measure actual vibration data. Instead it looks at the noise floor and uses statistical analysis to see any changes in the background noise. Network several of these sensors along a fault line, and you have yourself a low cost system that could see an earthquake coming, potentially saving thousands of lives.
[Michael] has a TON of data on his project page. Though he’s obviously very skilled, he is not an EE or software guy. He could use some help with the signal analysis and other parts. If you would like to lend a hand and help make this world a better place, please get in touch with him.
Continue reading “We Have A Problem: Earthquake Prediction”
[Andrea] built a seismic wave detector that warns of a possible impending earthquake. Because P waves travel much faster than the “make everything shake” S waves, building a device that detects P waves serves as an early warning system that alerts building occupants to go under a door frame. [Andrea]’s build detects these fast-moving P waves and only took an hour to make.
Last August, those of us on the east coast of the US had to live through Quakepocalypse, a magnitude 5.9 earthquake centered around Middle of Nowhere, Virginia. For those of us who have decided to stay, rebuild, and put our garden chairs upright again (so brave…), [Andrea]’s build could have been very useful.
The mechanics of the build is very simple: a pair of springs and levers are electrically wired together so that whenever there’s a sudden shock, a buzzer goes off. It’s very similar to an ancient Chinese earthquake detector that detects P waves by dropping a ball into a frog’s mouth.
While we’re not sure if a few of [Andrea]’s devices would be needed to detect P waves coming in off-axis, the build is simple enough to build dozens of them. Check out the video of the build in action
after the break here.