POSC Specifications Version 3.0 |
Epicentre Standard Values ref_north_axis_direction |
identifier | description | source | version | status |
---|---|---|---|---|
ref _version .identifier | ||||
true | The north direction as defined by the true north pole. The true north pole is an average of the actual measured north axis, which is the axis of rotation of the earth. | POSC | epicentre 2.1 | current |
magnetic | The north direction as defined by the magnetic north pole at the time of the measurement. The magentic north pole is the direction that a magnet will point to when freely rotating. | POSC | epicentre 2.1 | current |
local grid | The north direction is defined by the coordinate grid in the projection coordinate system. | POSC | epicentre 2.1 | current |
geodetic north | The north direction is the axis of symmetry of the ellipsoid that is used to define the geodetic coordinate system. | POSC | epicentre 2.1 | current |
unknown | It is not known which of the above is used to define the north direction. | POSC | epicentre 2.1 | current |