How to use the earthquake distance from s-p interval calculator
Estimate how far away an earthquake is from the time gap between P and S waves. Enter s–p arrival time difference, p-wave speed, s-wave speed in the fields above; the distance to earthquake are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “S-P time distance”, “how far was the earthquake”, “seismograph distance calculator”, “calculate earthquake distance from s-p interval”, “find distance to earthquake”.
Formula
Variables
- sp — S–P arrival time difference (s)
- vp — P-wave speed (km/s)
- vs — S-wave speed (km/s)
Worked example
With s–p arrival time difference = 10 s, p-wave speed = 6 km/s, s-wave speed = 3.5 km/s, the calculator gives distance to earthquake ≈ 84 km; distance to earthquake ≈ 52.19516 miles.
Frequently asked questions
What is the earthquake distance from s-p interval calculator used for?
Estimate how far away an earthquake is from the time gap between P and S waves. It helps with questions such as “S-P time distance”, “how far was the earthquake”, “seismograph distance calculator”.
What is the formula for the earthquake distance from s-p interval calculation?
Distance to earthquake (km) = sp × vp × vs / (vp-vs). Distance to earthquake (miles) = [Distance to earthquake] × 0.621371. Here sp is s–p arrival time difference (s), vp is p-wave speed (km/s), vs is s-wave speed (km/s).
What inputs do I need for the earthquake distance from s-p interval calculator?
You need s–p arrival time difference in s, p-wave speed in km/s, s-wave speed in km/s. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the earthquake distance from s-p interval calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the earthquake distance from s-p interval result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.