Parchmarks
Parch marks are a variation on cropmarks and soil marks where underlying archaeology shows though to the surface and may be observed, most easily from the air but also sometimes from the ground. They depend on thin soil and dry weather conditions to create a contrast between the area over the archaeology and the rest of the field, park or garden.
Parch marks are most commonly caused by buried stone or brick structures such as walls or paved areas. The stone inhibits the crop or grass roots in the overlying topsoil and the result is an area of weak growth which can show as a white or brown mark reflecting the shape of the archaeological structure underneath. In some cases, complex plans of villas, churches, Roman roads, long-demolished houses and industrial structures can be revealed in this way. As with cropmarks, further investigation using geophysics can reveal even more detail before any excavation takes place.
