To find the epicenter (the point on the earth's surface where an earthquake begins) during earthquakes, one need to view the seismogram (a record of the ground motion), and at least two other seismographs recorded for the same earthquake. Other instruments such as a map, a compass for sketching circles on the map, a ruler, and a pencil will also be used.
The following are the steps of the triangulation process in the correct order to find the epicenter during earthquakes:
Step 1: Subtract the time of P wave arrival from S wave arrival.
Step 2: See what the time difference is equal to in distance on a seismic wave chart.
Step 3: Draw circles representing the distances from at least three seismograph stations to the epicenter on a map.
Step 4: Find the point where all 3 circles intersect, and you've found the earthquake's epicenter.
The Appalachian Range includes Allegheny Mountains.<span>
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1. My predictions about the changes in sea level have been relatively close to the actual rise of the sea waters, though it has been different than the general predictions of the numerous models of the countries. The predictions that I have made about the rise of the sea level have been based on the rate of melting of the polar ice, but also on the isostatic rebound that occurs because of it, and the influence that the greenhouse gasses have on the global temperature. The estimates that I made were showing a rise of only few centimeters, unlike the several meters predicted by most of the models. The closest model to what I have predicted is the Russian model, which is very different than the others.
2. The sea level variations are not very easy to predict, nor do they have any particular cycle that is repeating on approximately the same time. There are numerous factors that influence the variations of the sea level, such as the global temperature, with higher temperature meaning higher sea levels, and lower temperature meaning lower sea levels. The isostatic rebound of the continental land masses should also be taken in consideration, as the continents lift up when they don't have pressure on top of them from the ice, and sink down when they do have large ice masses on them, thus it can influence where the water can penetrate and where it can't. The position of the landmasses, composition of the atmosphere, as well as the geological activities, all have big influence on the variations of the sea levels, be it going up or down.