Archaeology Underwater: The NAS Guide to Principles and Practice

BASICPRINCIPLES – MAKING THEMOST OF THECLUES 27

which was adapted from the study of geological strata,
can be summarized by the concept that a context which
physically overlays another context is the later (figure 4.8
and 4.9).

On a particular site, the principles of stratigraphy are

used to establish a sequence of above–below relationships,

thereby placing all the contexts (and, therefore, events)

into the order in which they occurred. Stratification can

be studied at different scales using the same basic theory.

Examining the layering of contexts in a scour pit may

reveal many clues about large-scale changes to a deposit.

Applying the same approach to the sediments between

individual timbers can be just as revealing about equally

fundamental processes in the formation of the site.

The principles of stratigraphy provide a framework

within which archaeological investigations are conducted.

They do not impose rigid boundaries on the way in

which stratification is investigated. Applying them effec-

tively requires a willingness to combine such principles

with a good understanding of the nature of the contexts

under investigation. For example, the nature of strati-

fication in mobile sediments is likely to be very different

to that in stable contexts. The application of stratigraphy

to a site on a rocky sea-bed will not be exactly the same

as its application to a deep urban deposit on land. But

the value of the exercise, its aims and fundamental prin-

ciples, will be precisely the same (figure 4.10). See chap-

ter 8 for information about how to record stratigraphy

(Harris matrix).

Site 1

Function

Date

Origin

Use

Associated

activities

Transport Type 1

Function

Date

Origin

Use

Associated

activities

Transport

Site 2

Function

Date

Origin

Use

Associated

activities

Transport

Site 3

Function

Date

Origin

Use

Associated

activities

Transport

Figure 4.7 Typology: knowledge about the appearance and character of a type of object is accumulated from a num-
ber of sites, which each contribute different elements. (Based on original artwork by Kit Watson)

1 m (39 in)

N

0

Figure 4.8 Stratigraphy from above: from the overlap it can
be concluded that the grave is earlier than the wall. (Based
on originalartwork by Ben Ferrari)