A column is a graphic representation of the several materials that we can find, in a determinate zone, as it has sedimented, the most ancient materials in the inferior part and the most modern in the superior part. To construct a stratigraphical column, it is necessary to measure in the field the thickness of all the shapes, starting on the lower and continuing towards the superior ones. It is necessary to avoid the tectonic structures that can remove a succession part or to duplicate it. In a map they can put on several columns, carried out in different places, in order to compare them and visualize how the sediments of a same age (color) change laterally of power (thickness) or of facies (type of sediment).

Imatge