This is because the waves fade as they get further away from the epicentre.
Energy in seismic waves is lost as they travel through the ground. As such the further they travel from the epicentre of the earthquake, the greater the energy loss and the less damage they can do.
At the epicentre which, is the central point from which it originates.
The proximity of the epicentre to populated or urban areas will effect the damage caused as the closer the earthquake's epicentre, the more energy will be retained by the earthquake waves and so the greater their capacity to cause damage.
The tectonic plates placed deep inside earth's crust [range may vary, say 5-100km]. As such, epicentre is defined as the centre point of the tectonic activity projected on earth's surface. Thus the epicentre can also lie on the surface of Sea/ Ocean also. Ocean water remains only up to 10 to 12 km deep [maximum being Marina Trench]The tectonic activity lies much below !!The epicentre is the point on the earth's surface directly above the earthquake's focus or hypocentre (the point within the earth where the fault rupture or movement actually occurs).As such, the seismic waves produced by an earthquake radiate away from this point. This is similar to the way waves or ripples in a pond move outwards in concentric circles from the point where you throw a stone into the water.
The time difference in arrival between P and S waves can help determine the distance to an earthquake epicenter. For each second of difference, the earthquake is roughly 7.5 kilometers away. So, a time difference of, for example, 10 seconds would indicate the earthquake is approximately 75 kilometers away.
The epicentre of an earthquake is the point on the earth's surface away from which the seismic waves produced by an earthquake radiate. This is similar to the way waves or ripples in a pond move outwards in concentric circles from the point where you throw a stone into the water. As such the epicentre is the point on the earth's surface directly above the earthquake's focus or hypocentre (the point within the earth where the fault rupture or movement actually occurs).
The town in Haiti was approximately 78 miles (125 kilometers) away from the epicenter of the earthquake.
Energy in seismic waves is lost as they travel through the ground. As such the further they travel from the epicentre of the earthquake, the greater the energy loss and the less damage they can do.
The S-P time method is perhaps the simplest method seismologists use to find an earthquake's epicenter. +++ No it's not. That finds its Focus. The Epicentre is the point of maximum movement on the land surface above the slip itself.
All other factors being equal, the seismic waves will be felt most strongly at or near to the epicentre of the earthquake.
Your standing on it! P-waves travel faster than S-waves through the Earth. As such the further away a seismometer station is from the epicentre of an Earthquake, the larger the difference between arrival times will be. By the same logic this means that the closer you get to the epicentre, the smaller the difference in arrival time will be until your at the epicentre when the difference will be zero!
At the epicentre which, is the central point from which it originates.
According to the US Geological Survey (USGS), the Earthquake was felt up to 50 km away from the epicentre. Please see the related link for a contour map of earthquake intensity from the USGS.
P-waves and S-waves are released by an earthquake at the same time and travel out from the epicentre in all directions. However P-waves travel faster than S-waves so the further away from the earthquake's epicentre the greater the lead the P-waves have on the S-waves. Observation of the seismogram trace at the seismometer station will allow the scientists to find the P-wave and S-wave arrival times and measure the difference between them. As the P-waves are faster they always arrive first (hence their name - primary wave). The greater the difference between the time that the P-waves and S-waves first arrive (i.e. the greater the lead the P-waves have), the further the distance to the epicentre. They are able to use the time difference along with an estimate of the speed of the P-waves and S-waves to find the distance from the station to the earthquakes epicentre. For more information on this please see the related question.
The proximity of the epicentre to populated or urban areas will effect the damage caused as the closer the earthquake's epicentre, the more energy will be retained by the earthquake waves and so the greater their capacity to cause damage.
The tectonic plates placed deep inside earth's crust [range may vary, say 5-100km]. As such, epicentre is defined as the centre point of the tectonic activity projected on earth's surface. Thus the epicentre can also lie on the surface of Sea/ Ocean also. Ocean water remains only up to 10 to 12 km deep [maximum being Marina Trench]The tectonic activity lies much below !!The epicentre is the point on the earth's surface directly above the earthquake's focus or hypocentre (the point within the earth where the fault rupture or movement actually occurs).As such, the seismic waves produced by an earthquake radiate away from this point. This is similar to the way waves or ripples in a pond move outwards in concentric circles from the point where you throw a stone into the water.
The time difference in arrival between P and S waves can help determine the distance to an earthquake epicenter. For each second of difference, the earthquake is roughly 7.5 kilometers away. So, a time difference of, for example, 10 seconds would indicate the earthquake is approximately 75 kilometers away.