Stratification (archeology) in the context of "Spit (archaeology)"

In the field of archaeology, a spit is a unit of archaeological excavation with an arbitrarily assigned measurement of depth and extent. It is a method of excavation employed without regard to the archaeological stratigraphy that may (or may not) be identifiable at the archaeological site under investigation. The method of excavating in arbitrary spits is most frequently encountered at site excavations which lack any visible or reconstructable stratigraphy in the archaeological context, or when excavating through intrusive or fill deposits.