Gathering the Data

A single small plane carries the instruments used to take radiometrics and magnetics measurements. Although gravity measurements can be collected from an aircraft, greater sensitivity and accuracy is obtained from ground surveys. The aircraft flies at a set height in order to take measurements at a given height above the ground. The plane will typically fly about 80-100m above the ground along survey lines around 200-400m apart. When the aircraft approaches a hill followed by a valley, ideally it must maintain its height at 80-100m above the hill then drop down into the valley to maintain a constant height above the ground. In practice this may be difficult because a plane can only climb 50 metres over one kilometre. Where the terrain is too severe, a helicopter is used. The cost of a helicopter is much greater than that of a plane.

Flight path to Ground level

During a survey, data for an entire area is collected at points along these survey lines. This data is then processed to remove non-geological background information (mentioned below) for the specific data type.

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