<p>The magnitude of an earthquake is related to the total energy released, therefore to estimate it from a seismogram you need to know the distance to the source. In the case of the <a href="https://en.wikipedia.org/wiki/Richter_magnitude_scale" rel="nofollow noreferrer">Richter scale</a> for example, the relationship between magnitude and seismogram amplitude is defined for a standard distance.</p>

<p>If you have only one seismograph, you can not triangulate the location of the source (<a href="https://en.wikipedia.org/wiki/Hypocenter" rel="nofollow noreferrer">hypocenter</a>). Therefore, you can not estimate the magnitude of a seismic event (Richter or <a href="https://en.wikipedia.org/wiki/Moment_magnitude_scale" rel="nofollow noreferrer">moment magnitude</a>).</p>

<p><strong>But you can estimate the <a href="https://en.wikipedia.org/wiki/Seismic_intensity_scales" rel="nofollow noreferrer">local seismic intensity</a> of the event</strong> at the particular location of your instrument. With the accelerometer data you can easily measure the <a href="https://en.wikipedia.org/wiki/Peak_ground_acceleration" rel="nofollow noreferrer">peak ground acceleration</a>, that can be used to estimate the intensity in any of the <a href="https://en.wikipedia.org/wiki/Seismic_intensity_scales" rel="nofollow noreferrer">existing scales</a>. For example, the peak ground accelerations associated to each intensity level in the commonly used <a href="https://en.wikipedia.org/wiki/Mercalli_intensity_scale" rel="nofollow noreferrer">Mercalli intensity scale</a> are:</p>

<p><a href="https://i.sstatic.net/F6aGo.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/F6aGo.png" alt="table of intensities"></a></p>

<p>Those <em>g</em> values would be easy to calculate with the accelerometer data and proper calibration constants.</p>

<p><em>Table taken from the Wikipedia page for <a href="https://en.wikipedia.org/wiki/Peak_ground_acceleration" rel="nofollow noreferrer">peak ground acceleration</a></em></p>

<p>You might want to have a look at <a href="https://earthscience.stackexchange.com/questions/4681/characterizing-earthquakes-using-accelerometer-data">this question</a>. There are some nice answers and references that you might find useful.</p>

CC BY-SA 3.0
2018-03-03T21:17:37.360Z
2018-03-06T00:16:08.117Z
2018-03-06T00:16:08.117Z
Camilo Rada
<p>I'm using ADXL345 accelerometer with Raspberry Pi to build a seismograph. I've successfully hooked it up and can plot the accelerometer data in three axis. Is there any way to express these data in the form of the magnitude of an earthquake, of course, at the point of sensing? I know that it might be imprecise, but any representation would be helpful (e.g. Richter scale), and how to accomplish that.</p>

CC BY-SA 3.0
2017-03-03T17:26:41.547Z
You will need to work on scaling and interpretation, but in theory what you propose will work.  I worked in inertial navigation in the 80's, with gyros and accelerators, and we would routinely plot earthquakes when running table tests.  It was impressive to see, but standard seismographs were much easier to read and interpret even with the high accuracy acceleratorometers we used.  I would tend to expect you could achieve detection of near events, but not high accuracy of magnitude or range.
dlb
CC BY-SA 3.0
2017-03-03T21:43:30.183Z
these two articles may help you scroll down to data and resources for the first one for directions. http://srl.geoscienceworld.org/content/87/1/186 And this one includes more construction oriented instructions http://www.instructables.com/id/This-Seismometer-is-no-toy/
John
CC BY-SA 3.0
2017-03-06T11:04:09.993Z
@dlb I need more data on how to do the scaling, since I'm not a geologist, but an engineer.
yode
CC BY-SA 3.0
2017-03-06T11:07:50.727Z
@John I've seen these two papers before. In the first one, the scaling wasn't done. In the second one, I don't need to construct actual seismograph, only to use already hooked-up accelerometer.
yode
<earthquakes><seismology><instrumentation><in-situ-measurements><diy>
Using accelerometer as a seismograph
yode
# Using accelerometer as a seismograph

(Asked by: username_0 on 2017-03-03)

I'm using ADXL345 accelerometer with Raspberry Pi to build a seismograph. I've successfully hooked it up and can plot the accelerometer data in three axis. Is there any way to express these data in the form of the magnitude of an earthquake, of course, at the point of sensing? I know that it might be imprecise, but any representation would be helpful (e.g. Richter scale), and how to accomplish that.

**Tags:** earthquakes, seismology, instrumentation, in-situ-measurements, diy

> **Comments:**
> **username_1**: You will need to work on scaling and interpretation, but in theory what you propose will work.  I worked in inertial navigation in the 80's, with gyros and accelerators, and we would routinely plot earthquakes when running table tests.  It was impressive to see, but standard seismographs were much easier to read and interpret even with the high accuracy acceleratorometers we used.  I would tend to expect you could achieve detection of near events, but not high accuracy of magnitude or range.  
> **username_2**: these two articles may help you scroll down to data and resources for the first one for directions. http://srl.geoscienceworld.org/content/87/1/186 And this one includes more construction oriented instructions http://www.instructables.com/id/This-Seismometer-is-no-toy/  
> **username_0**: @username_1 I need more data on how to do the scaling, since I'm not a geologist, but an engineer.  
> **username_0**: @username_2 I've seen these two papers before. In the first one, the scaling wasn't done. In the second one, I don't need to construct actual seismograph, only to use already hooked-up accelerometer.  

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## 1 answers

### Answer by username_3 on 2018-03-03. Score: 7 | Accepted answer

The magnitude of an earthquake is related to the total energy released, therefore to estimate it from a seismogram you need to know the distance to the source. In the case of the [Richter scale](https://en.wikipedia.org/wiki/Richter_magnitude_scale) for example, the relationship between magnitude and seismogram amplitude is defined for a standard distance.

If you have only one seismograph, you can not triangulate the location of the source ([hypocenter](https://en.wikipedia.org/wiki/Hypocenter)). Therefore, you can not estimate the magnitude of a seismic event (Richter or [moment magnitude](https://en.wikipedia.org/wiki/Moment_magnitude_scale)).

**But you can estimate the [local seismic intensity](https://en.wikipedia.org/wiki/Seismic_intensity_scales) of the event** at the particular location of your instrument. With the accelerometer data you can easily measure the [peak ground acceleration](https://en.wikipedia.org/wiki/Peak_ground_acceleration), that can be used to estimate the intensity in any of the [existing scales](https://en.wikipedia.org/wiki/Seismic_intensity_scales). For example, the peak ground accelerations associated to each intensity level in the commonly used [Mercalli intensity scale](https://en.wikipedia.org/wiki/Mercalli_intensity_scale) are:

[![table of intensities](https://i.sstatic.net/F6aGo.png)](https://i.sstatic.net/F6aGo.png)

Those *g* values would be easy to calculate with the accelerometer data and proper calibration constants.

*Table taken from the Wikipedia page for [peak ground acceleration](https://en.wikipedia.org/wiki/Peak_ground_acceleration)*

You might want to have a look at [this question](https://earthscience.stackexchange.com/questions/4681/characterizing-earthquakes-using-accelerometer-data). There are some nice answers and references that you might find useful.


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