Well-dated fluvial sequences as templates for patterns of handaxe distribution : understanding the record of Acheulean activity in the Thames and its correlatives.

The use of Acheulean (handaxe) typology as a cultural and temporal marker has been a topic of controversy in recent decades, with many archaeologists continuing to reject such an approach out of hand. Much of the controversy stems, however, from difficulties in reconciling the archaeological record from Quaternary sediments with a flawed and overly simplified chronostratigraphical template. With the adoption of the ‘expanded chronology’ based on the marine oxygen isotope record, underpinned by biostratigraphical and geochronological dating, has come the recognition of a meaningful progression of artefact types, such as the first appearance of Levallois technique, attributed to MIS 9–8 over widespread parts of the Old World. More recently it has been established that assemblages in Britain with twisted ovate handaxes in significant numbers represent MIS 11 occupation, while those with significant proportions of cleavers and ‘ficron’ handaxes appear to be correlated with deposits formed at around the time of the MIS 9 interglacial. The recognition of such patterns stems largely from the well-dated Thames sequence; it should not be confused with the previous use, in the mid-20th century, of archaeological typology as a crude dating indicator based on a relative refinement of tool making. Key means of age constraint for the Thames sequence have been mammalian assemblage zones representing the last four interglacial cycles, molluscan biostragraphy and amino acid racemization dating of molluscan material, especially the calcitic opercula of the gastropod Bithynia tentaculata, thus providing a framework within which the archaeological patterns can be identified.