The oldest preserved geologic map is the Turin papyrus (1150 BCE), which shows the location of building stone and gold deposits in Egypt.

Trend and plunge are often notated as PLUNGE → TREND (for example: 34 → 86 indicates a feature that is angled at 34 degrees below the horizontal at an angle that is just east of true south). The arrow is oriented in the downgoing direction of the linear feature (the 'trend') and at the end of the arrow, the number of degrees that the feature lies below the horizontal (the 'plunge') is noted. Trend and plunge are used for linear features, and their symbol is a single arrow on the map. In the azimuthal system, strike and dip are often given as 'strike/dip' (for example: 270/15, for a strike of west and a dip of 15 degrees below the horizontal). The angle that the bed makes with the horizontal, along the dip direction, is written next to the dip line. Strike and dip symbols consist of a long 'strike' line, which is perpendicular to the direction of greatest slope along the surface of the bed, and a shorter 'dip' line on side of the strike line where the bed is going downwards. Orientations of planes are measured as a 'strike' and 'dip', while orientations of lines are measured as a 'trend' and 'plunge'. Geologists take two major types of orientation measurements (using a hand compass like a Brunton compass): orientations of planes and orientations of lines.

A standard Brunton Geological compass, used commonly by geologists

Geologic cross section maps