Calculator Inputs
Choose a calculation mode. Then enter the required seismic values.
Output Metrics
Each whole magnitude step equals ten times higher wave amplitude.
A one unit increase releases about 31.6 times more energy.
Helpful for teaching, comparison, and quick seismic interpretation.
Magnitude Trend Graph
This graph shows relative amplitude and relative energy growth across magnitudes 1 to 9.
Example Data Table
| Case | Amplitude (mm) | Distance (km) | Magnitude | Estimated Energy (J) |
|---|---|---|---|---|
| Local micro event | 0.20 | 12 | 1.26 | 4.57E+06 |
| Minor felt quake | 1.50 | 30 | 3.64 | 1.68E+10 |
| Moderate regional event | 8.00 | 85 | 5.82 | 3.15E+13 |
| Strong damaging event | 18.50 | 120 | 6.82 | 9.94E+14 |
Formula Used
The calculator uses educational forms of standard local magnitude relations. For amplitude and distance mode, it applies:
Here, Aum is seismic amplitude in micrometers and D is epicentral distance in kilometers.
For energy mode, the calculator applies:
This returns seismic energy E in joules from magnitude M.
For comparison mode, it uses:
These relationships explain why small magnitude changes can represent much stronger earthquakes.
How to Use This Calculator
- Select the required calculation mode.
- Enter amplitude and distance, or enter one or two magnitudes.
- Press Submit to display the result above this form.
- Review the derived metrics, event class, and formula summary.
- Use the CSV button to export result data.
- Use the PDF button to save a printable report view.
This tool supports classroom work, quick checks, and simple reporting. It does not replace formal seismological inversion methods.
About Richter Scale Analysis
The Richter scale expresses earthquake size using a logarithmic magnitude system. It was developed for local events and instrument-based comparisons.
Because the scale is logarithmic, the difference between magnitude values is not linear. A moderate increase can mean much stronger ground motion.
Magnitude estimates depend on instrument response, wave type, path effects, and site conditions. This calculator offers simplified educational estimates for quick interpretation.