Questions: Stratigraphic Interpretation in Archaeology

Question 1

An excavator finds Roman pottery sherds in what appears to be a Bronze Age deposit. What is the most archaeologically sound interpretation?

• A. Romans traded with Bronze Age peoples, and this confirms that contact
• B. The dating of the Bronze Age deposit must be wrong — it is actually Roman
• C. A Roman-period pit or feature cut through the Bronze Age layer, depositing the sherds below ground level as intrusive material
• D. Bioturbation mixed artifacts from the two periods into the same layer

Answer: (C)

This is the classic intrusive feature scenario. A pit, well, or burial dug during the Roman period would cut through earlier Bronze Age deposits. When infilled, Roman material is deposited physically below the Roman surface but within what otherwise appears to be Bronze Age stratigraphy. The archaeologist must identify the cut — the boundary where the Roman feature intersects the Bronze Age deposit — and associate the pottery with the feature, not the layer. Option A assumes the association is real when it is a product of disturbance. Option D is possible but bioturbation typically moves small objects (seeds, small bones), not pottery sherds.

Question 2

An arrowhead is recovered by a looter at an archaeological site and sold. What information is permanently lost that proper excavation would have preserved?

• A. The arrowhead's material composition and manufacturing technique
• B. Its stratigraphic position, spatial associations with other objects and features, and layer sequence — its context
• C. Its approximate age, which can still be determined by typological analysis
• D. Its function, which can still be inferred from its form

Answer: (B)

The arrowhead's material, manufacture, and typology survive and can be analyzed regardless. What is permanently and irrecoverably lost is context: which layer it came from (relative date), what objects it was found with (association), what feature it was near (function clues), and its spatial orientation. Was it in a burial, implying ritual use? In a midden, implying food procurement? In a forge deposit, implying manufacture? Context answers these questions; the object alone cannot. Context is the primary source of meaning — often more important than the object itself.

Question 3

An artifact removed from its stratigraphic context can still yield information about its manufacturing techniques and material composition, but has permanently lost its contribution to relative dating sequences.

• T. True
• F. False

Answer: True

Correct on both counts. Compositional analysis (XRF, SEM), typological comparison, and use-wear analysis can all be applied to decontextualized objects. What cannot be recovered is chronological and associative information: its layer, its neighbors, its feature association. A Bronze Age pot analyzed in isolation tells you about Bronze Age pottery-making; the same pot in situ tells you about a specific community at a specific time engaged in specific activities. The loss is real, permanent, and irreversible.

Question 4

Because layers accumulate from bottom to top, any artifact found in a lower layer at a site is typically older than any artifact found in an upper layer.

• T. True
• F. False

Answer: False

The law of superposition applies to undisturbed deposits, but real archaeological sites are full of disturbances. Intrusive features — pits, wells, post-holes, burials — cut through earlier layers and deposit later material at lower physical depths. A Bronze Age burial cut into a Neolithic deposit places Bronze Age skeletal remains physically below the level of the Neolithic material. Bioturbation can also move artifacts vertically. Physical depth is not the same as date; interpreting stratigraphy requires identifying cuts, recognizing intrusions, and distinguishing primary from secondary deposits.

Question 5

What does 'archaeological context' mean, and why is it described as irreplaceable?

Model answer: Archaeological context is an artifact's stratigraphic position (which layer it came from), its spatial relationships with other artifacts and features, and its associations within the broader assemblage. It is irreplaceable because excavation destroys the stratigraphy: digging removes the layers and their relationships permanently. Once a site is excavated, those spatial and stratigraphic associations cannot be reconstructed — there is no material remaining to re-examine. Context is not merely helpful background information; it is where most of an artifact's historical meaning resides.

The phrase 'stratigraphy is a document destroyed in the reading' captures the fundamental asymmetry. Unlike a book that can be re-read, an archaeological deposit is consumed by the act of excavation. This is why careful, systematic recording — layer by layer, feature by feature, artifact by artifact — is the ethical and methodological core of archaeological practice. A poorly excavated site represents a permanent loss of knowledge, because the one-time opportunity to read its stratigraphy has been squandered.