From SEG Wiki
Jump to navigation Jump to search

An imaginary terrain, depicted by a topographic map, can be used to visualize the traveltime configuration. Topographic maps provide information about elevation of the terrain’s surface above sea level. Elevation is represented on a topographic map by contour lines. In effect, the contour map of the terrain represents a scalar function. Each point on a contour line has the same elevation. In other words, a contour line represents a horizontal slice through the land surface. A set of contour lines tells you the shape of the land. For example, hills are represented by concentric loops, whereas stream valleys are represented by V shapes. Steep slopes have closely spaced contour lines, whereas gentle slopes have very widely spaced contour lines. The contour interval is the difference in elevation between adjacent contour lines.