What is a satellite survey?
Satellite survey remote sensing utilise satellite imagery which have been processed using commercial geographic information system software. Three-space co-ordinate maps are generated, with an accuracy determined by the datum position accuracy and optical resolution of the satellite platform.
Are satellite surveys accurate?
Generally speaking, the accuracy of Static GPS Baseline measurements are one part per million, meaning that a 30 kilometer distance can be measured with about 30 mm of uncertainty.
How is a topographic survey performed?
All survey points are measured by the instrument with an onboard feature code list. For example, the surveyor can string survey points to create an outline of a building with a specific code. GPS and laser scanning equipment can also be used, subject to the site specification and terrain.
What is the use of GPS in surveying?
GPS is especially useful in surveying coasts and waterways, where there are few land-based reference points. Survey vessels combine GPS positions with sonar depth soundings to make the nautical charts that alert mariners to changing water depths and underwater hazards.
What is triangulation method in surveying?
Triangulation is a surveying method that measures the angles in a triangle formed by three survey control points. Each of the calculated distances is then used as one side in another triangle to calculate the distances to another point, which in turn can start another triangle.
Do I need a topographic survey?
Topographic surveys are typically carried out when an area is being assessed for new construction or the addition of new development. The survey is invaluable for showing what the land looks like now, and how it will impact design and construction.
How long does a topographic survey take?
Once the site work is done, the processing and QC of your drawings back at the office can take 1-2 days. So, around a week in total. For a premium, we can offer weekend surveys and get things out a bit quicker if you’re really pushed for time.
What is topographic method?
Topographic Surveying. determining the relative locations of points (places) on the earth’s surface by measuring horizontal distances, differences in elevation and directions.
What is the working principle of GPS?
The working/operation of the Global positioning system is based on the ‘trilateration’ mathematical principle. The position is determined from the distance measurements to satellites. From the figure, the four satellites are used to determine the position of the receiver on the earth.
How is a topographical survey of a property done?
The Surveyor in making topographic surveys uses accepted terrestrial or GPS surveying methods. Topographic surveys that additionally depict the location of property lines must also be in compliance with the current standard for property surveys. 3.
How are satellite images used in surveying and surveying?
Using satellite images, PhotoSat’s proprietary processing methods enable exploration targeting through the clear and reliable identification of alteration minerals. Accurate topographic mapping and surveying of a mining exploration project requires a significant investment of time and resources.
What can you do with the USGS topoView?
As the years passed, the USGS produced new map versions of each area. TopoView shows the many and varied topographic maps of each of these areas through history. This can be particularly useful for historical purposes, such as finding the names of natural and cultural features that have changed over time.
Where can I find topographic maps from the USGS?
Geologic mapping and topographic mapping at the USGS have a long tradition together (see 1888 report ). The NGMDB project is proud to assist the NGP in bringing these maps to the Web. The maps shown through topoView are from the USGS’s US Topo series and earlier Historical Topographic Map Collection (HTMC).