National Gravity Network (NGN) is the network of Stations distributed within the Kingdom of Saudi Arabia where the measurement of gravity has been determined by absolute or relative methods. The main goal of NGN is to support geodetic activities in development and maintenance of the Vertical Reference Frames and geoid models for the Kingdom. NVN consists of the following elements:
- Absolute Gravity Network
- Relative Gravity Network
- Absolute Gravity Calibration Baseline
Absolute Gravity Network
Absolute Gravity Network (AGN) is established to define the absolute g-value (Gravity Reference) and its gradient (Calibration) from Gravity values observed directly at network stations with gravimetric techniques and instruments. The AGN was developed according to the second order, class one NGS standards and includes 41 stations with measured gravity values of accuracy 10 µGal.
Relative Gravity Network
Relative Gravity Network is established to densify measurements of absolute gravity by using relative gravimetric techniques and instruments. It is developed according to the NGS standards and includes 3836 stations with available gravity values of accuracy better than 20 µGal.
Gravity Calibration Baseline
Gravity Calibration Baseline is established was established to provide Calibration services for gravimetric techniques and instruments. It is developed according to the NGS standards and includes 14 stations with available gravity values of accuracy better than 10 µGal.
GCB Map with approximate locations (KMZ) To get data from NGN, follow steps described below:
- Download any of National Gravity Network (NVN) maps in KMZ format.
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Select required gravity stations located in the area of your interest.
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Request the data you need by using the email address: info@gcs.gov.sa using the information described above.