Geological cross-sections

Geological cross-sections are graphical representations of the distribution of rock units in vertical planes cut through landscapes. Cross-sections extrapolate the boundaries between rock units above and below ground. This chapter provides practical advice on how to create geological cross-sections through the interpretation of maps with an emphasis on recognizing the key features that reveal the orientation of boundaries and structures. Topography lines can be sketched with reasonable accuracy rather than transferred from maps. The use of sketch cross-sections as an interpretative diagram is introduced, and examples given to illustrate how these can be used in field notes to assist in the analysis of geological structures.