Soil and Archaeology

Soil is very important for archaeologists, because it provides a source of information about the past climate, vegetation and animals (ecofacts), as well as man-made artefacts such as ancient metal tools, coins etc.

Soil can preserve all kinds of things for thousands of years. However, its ability to do this depends on the soil conditions, especially the amount of water present in the soil throughout the time the items are buried. Waterlogged soils are particularly good at preserving objects, because they contain very little dissolved oxygen, which is needed by the soil organisms responsible for decay.

Searching for ‘ecofacts’ such as plant and animal remains, is a useful means of reconstructing how the ecology and environment of the surrounding land may have once been, and how it has changed. Fossilised snails and insects are particularly good for estimating past climate, whilst preserved pollen grains and seed can reveal which plant species made up the natural vegetation.

Additionally, soil and crop marks (best visible from the air in dry weather) are good indicators of past use of the land. These markings generally appear due to different levels of crop growth caused by buried structures such stone-walls and refilled ditches.