Reverse stratigraphy (sometimes known as inverted stratigraphy) is the result of a process whereby one sediment is unearthed by human or natural actions and moved elsewhere, whereby the latest material will be deposited on the bottom of the new sediment, and progressively earlier material will be deposited higher and higher in the

stratigraphy Stratigraphy is a branch of geology concerned with the study of rock layers ( strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithost ...

. Such events can be triggered by

rockslide A rockslide is a type of landslide caused by rock failure in which part of the bedding plane of failure passes through compacted rock and material collapses ''en masse'' and not in individual blocks. Note that a rockslide is similar to an avalanc ...

tree throw In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are u ...

s, or other events which cause the strata of a deposit to be flipped or reversed. In archeological

excavations In archaeology, excavation is the exposure, processing and recording of archaeological remains. An excavation site or "dig" is the area being studied. These locations range from one to several areas at a time during a project and can be condu ...

a common cause of inversions in the stratigraphy is the collapse of walls on river banks or other raised mounds where deposits which have been cut through behind the wall prior to collapse slip over the collapsed structure resulting in the structure being under the deposits that originated earlier in time. In this case care must be taken to re-

context Context may refer to: * Context (language use), the relevant constraints of the communicative situation that influence language use, language variation, and discourse summary Computing * Context (computing), the virtual environment required to s ...

the slipped deposits so the event of slippage appears in the correct place stratigraphically in the

Harris matrix The Harris matrix is a tool used to depict the temporal succession of archaeological contexts and thus the sequence of depositions and surfaces on a 'dry land' archaeological site, otherwise called a 'stratigraphic sequence'. The matrix reflect ...

. There are numerous process that can reverse the stratigraphy or more accurately redeposit it. Many rely on slope processes, however other instances where deposits containing material later than overlying deposits occur in such features as drains or hypocaust systems. In these instances a clear understanding of the direction of "UP" and site formation processes is essential. Drains or hypocaust systems often have later material deposited within them during their "use", which may be much much later than either their initial construction or indeed the construction, use and disuse of the floors above them. Other human intervention, such as altering the ground level for architectural purposes by way of filling, can lead to an inversion of the stratigraphic layers.Rowe, J. (1961)
Stratigraphy and Seriation.
American Antiquity, 26(3), 324-330. doi:10.2307/277399

References

{{DEFAULTSORT:Reverse Stratigraphy Stratigraphy Methods in archaeology

See also

References