GEOLOGY

Detailed explanation-1: -True north, on the other hand is the direction from a given location to the north geographic pole. The angle between magnetic north and true north is called magnetic declination.

Detailed explanation-2: -If the Earth were not tilted on its axis of rotation, the declination would always be 0°. However, the Earth is tilted by 23.45° and the declination angle varies plus or minus this amount. Only at the spring and fall equinoxes is the declination angle equal to 0°.

Detailed explanation-3: -The difference is the 8° angle from True North to Magnetic North plus the 0° 23’ angle from True North to Grid North. Thus to convert from a magnetic bearing to a Grid North reference you would subtract 8° 23’.

Detailed explanation-4: -The magnetic inclination is the angle between the earth’s surface and the magnetic field lines. Magnetic declination is the angle between the magnetic north of the compass and the true north. The declination can be measured using a compass, the direct measurement method, and a map.