Hachured contour lines are circular lines on a topographic map that have little teeth, or hash marks, that point into a depression that is below a higher elevation. Also known as depression contours, common geologic features indicated by hachured contour lines include craters and cones of volcanoes.Know More
Concentric circles with hachure marks in the middle denote a hill with a depression on top. For instance, the top line of concentric circles could indicate 1,397 feet above sea level. The next, inner contour line could indicate an elevation of 1,200 feet above sea level. The next innermost circle could be 1,000 feet high. The two contour lines inside the line of 1,397 feet would have hachures to indicate lower elevations inside a high elevation on the map. Small hachure marks point towards the inside of the concentric circles.
Sometimes, hachure contour lines repeat the previous elevation simply because cartographers denote a downslope rather than an upslope. Elevations that decrease, rather than increase, within concentric circles are indicated by red dots with specific elevation numbers. Nearby points with definitive elevations have blue dots to mark higher points than those of the depression.
The term hachure comes from the French word "hacher," which means "to chop up" or "to hatch," as with a hatchet. This connotes small lines that cut a larger line into smaller pieces on a topographic map.Learn more about Drawing
Contour lines on a map indicate elevation or depth. Numeric notations on contour lines refer to the level of elevation, or height above sea level.Full Answer >
A depression contour line is a marking on a map indicating a low point of land completely surrounded by more elevated land. The area is represented by closed concentric lines. The inner depression contour lines indicate lower elevations, with the elevation increasing with each outer layer.Full Answer >
On topographic maps, V-shaped contour lines that point downhill indicate sharp, narrow ridge lines. Ridge lines help people recognize areas of high and low ground when hiking, fishing, hunting or engaging in other outdoor activities.Full Answer >
The term "contour interval" refers to the vertical distance between contiguous contour lines in terms of elevation. Commonly illustrated on a topographic map, the elevations between contour lines are uniformly spaced along vertical distances.Full Answer >