How many detection centers are necessary to pinpoint the location of the epicenter of an earthquake?

Answer 1

Three at least. A cicle is drawn keeping that recording station as center. Two circles can cut at two places on their circumference, whereas three circles definitly cut at a common place, indicating the origin of earthquake place(epicenter).

Answer 2

3. Draw a dot in the middle of a piece of paper. This is the epicentre of your earthquake. Now imagine you have 1 detection centre (seizmographs is it?) that says this earthquake happened 5 miles away. Scale this down to 5 cm and draw a cross 5cm from your epicentre. Now draw a circle of radius 5 cm around this cross. This circle shows all the possible locations that, according to this one detection centre, the epicentre could be. Now say another detection centre says an earthquake happened 7 miles away. Again, scale down to 7cm and draw another cross 7cm from your epicentre. Draw your 7cm radius circle and you will see that the 2 circles you now have cross over at 2 points. These 2 points are the 2 places at which the earthquakes epicentre could be. However, you don't know which one it is. You need a third detection centre to tell you this. Hope this helps, not sure if I've explained it very well.

Answer 3

Seismographs do not pinpoint the epicentre of the earthquake, they pinpoint the centre of it. This is well below the surface. Once the location of the earthquake has been determined, the epicentre is the point on the surface directly above it. All you need for that is a map once the earthquake itself has been fixed.

Answer 4

Yes - a minimum of 3 will triangulate the epicentre by calculating the variances.

Answer 5

Probably 4 (like GPS) in order to also get the depth inside the earth.

Answer 6

at least 3

Answer 7

You need three to triangulate the position.