It's sort of like if you were to make a five layer cake with each cake layer being a different colour. If you looked at it from the side you would see all the different levels. A profile of a unit helps to understand the levels that the archaeologist dug as well as any change in human activity over time. See a profile. The provenience of the artifact or feature is recorded by an archaeologist in the fieldbook and on the artifact bag.
Provenience is important because it gives people a history on the object - where it was on the site.
Stratigraphy Stratigraphy refers to the interpretion of the layers in archaeological deposits. If the stratigraphy gets mixed up, for example, if someone digs a hole down into it then interpretation is much more difficult and sometimes impossible. Artifacts are no longer in context. By examining and analyzing the layers and the artifacts in them, archaeologists can learn how past people lived and what kinds of things they did. Tape Measure Tape measures are used for laying out grids over an archaeological site, for measuring the unit to make sure it is square, for measuring level depths and for measuring features from the corner of the unit.