A topographical survey is an assessment to determine the configuration of the earth's surface. It generally concerns the relief of the earth (or moon, planet or asteroid), which can also include artificial and natural feature such as hills, valley, depressions, streams, dams, bridges and buildings. The recording of relief or terrain involves determining the terrestrial or three-dimensional space position of points and the distances and angles between them. A graphic representation of the relief of an area is called a topographic map, which will be constructed from data which shows the horizontal and vertical locations plotted in the survey. Digital surface models and digital terrain models can show the 3D representation of the results of a topographical survey, with or without objects such as plants or buildings.
A topographical survey is a form of land surveying which measures the elevation of plots on a particular piece of land, which are presented as contour lines on a plot. A topographical survey uses astheodolites, dumpy levels and clinometers, which will measure the distances and angles between points. Direct surveys such as these can be manual or GIS-based, the latter being a computerised system used to capture, store, manipulate, analyse, manage and present the findings of the topographical survey.
A topographical survey may be conducted for a number of reasons. The plotting of points in a horizontal coordinate system such as latitude, longitude and altitude may be commissioned by architects or engineers before building or installing drainage They are also carried out for other reasons such as archaeological digs, reclamation projects, military planning and geological exploration.
A topographical survey is a form of land surveying which measures the elevation of plots on a particular piece of land, which are presented as contour lines on a plot. A topographical survey uses astheodolites, dumpy levels and clinometers, which will measure the distances and angles between points. Direct surveys such as these can be manual or GIS-based, the latter being a computerised system used to capture, store, manipulate, analyse, manage and present the findings of the topographical survey.A topographical survey may be conducted for a number of reasons. The plotting of points in a horizontal coordinate system such as latitude, longitude and altitude may be commissioned by architects or engineers before building or installing drainage They are also carried out for other reasons such as archaeological digs, reclamation projects, military planning and geological exploration.
There are other types of topological survey than a direct survey. Some studies are carried out at a distance from the subject area, called remote sensing. Aerial and satellite imagery are a part of geovisualisation. Aerial and satellite imagery use a non-visual spectra of light to determine the lie of the land, showing vegetation and other land use information in a more detailed way. Photogammetry can be used to survey a 3D surface by using a number of photographic images taken from different positions, usually from different passes of an aerial flight.
Radar and sonar are used to generate Digital Elevation Models. Using sonar to determine the terrain of the ocean floor is an example of sonar mapping in use. A light detection remote sensing technique is another method being used in topography, which uses a laser instead of radio waves.
Topography is also used in medical practice, for brain mapping, measuring the curvature of conea, and superficial human anatomy. It is also used in mathematics when measuring the variables in a map or space.
Radar and sonar are used to generate Digital Elevation Models. Using sonar to determine the terrain of the ocean floor is an example of sonar mapping in use. A light detection remote sensing technique is another method being used in topography, which uses a laser instead of radio waves.
Topography is also used in medical practice, for brain mapping, measuring the curvature of conea, and superficial human anatomy. It is also used in mathematics when measuring the variables in a map or space.
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