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The information obtained from measuring gravity can be used in several fields of application, such as calculation of levelling data, geoid determination and geological mapping.
Levelling
Gravity must be known in order to be able to calculate heights above the sea from spirit levelling. When levelling, instruments and rods are set up and by means of a level, which means that the levelling becomes dependent on the vertical line, i.e. the direction of gravity. The irregularities in the gravitational field mean that the surfaces that are perpendicular to the vertical lines are not parallel along the levelling line. This in turn means that a balance between two points gives slightly different results along different paths. In order to obtain unambiguous values for the heights, one must include gravity in altitude calculations.
The geoid
Gravity is of fundamental importance for the problems associated with the geoid, its determination and use.
Exploration
Local variations in the gravitational field can reveal mineral deposits in the earth's crust. Greater than normal gravity values can, for example, indicate ore deposits and lower values can indicate oil or gas deposits.
Geological mapping
When mapping for geological maps, gravity measurements are used to obtain the boundaries between different kinds of rock. For this purpose, a local densification of the nationwide network is often carried out.
Calibration
Sometimes knowledge of gravity is needed for technical reasons. It is needed, for example, when using sensitive measuring devices in which balance weights are included. Lantmäteriet receives, because of this, some inquiries annually about gravity in various places in Sweden.