Trenches are usually used to expose bedrock buried under shallow outcrops and are often dug across the bedrock extension or mineralization zone under investigation.

Trenches are ideal complements to RAB and RC drilling, i.e. When structural data from trench mapping is needed to supplement lithological information obtained from boreholes. In some cases, this work is done with the aim of completely removing the shallow overburden and reaching large areas of bedrock. This is done with bulldozers or by cutting with high-pressure water hoses. Then it is possible to examine and sample the bedrock in more detail. Because the process is environmentally destructive and reclamation can be costly, extensive excavation is typically performed when a target mineralization zone has been defined and there are specific sampling or geological problems that require This type of complete removal is to achieve the result. In mining, trenching is usually used in order to prepare samples from inside the trenches and for more detailed investigations in the exploration stages.