This report documents the attempts to conduct amino acid racemization analysis for age estimation. It is concluded that while Pennington is clearly younger than all other sites, it is difficult to assess how much younger as the shells have suffered dissolution. We suggest that Norton Farm is MIS 7a, that Portfield Pit is MIS7 and that Portfield Pit Tr 31-10-96 Unit VII younger than other Portfield Pit samples. The remainder of putative MIS 7 sites contain only one or two species none of which occurs at more than one other site. These sites are Oving, Yeoman's Road, Lepe and Selsey. None of these is convincingly younger (but there is a significant caveat that we do not know enough about racemization in the species we have studied). On the basis of Macoma data alone, it seems difficult to separate Oving, Yeoman's Road, and Portfield Pit. The remaining three sites Red Barnes, Harnham, and Brooks Field North all have higher ranges in their DL values. It is difficult to say more than all three sites are MIS9, although given the cold-stage character of Harnham, the DL data are not inconsistent with an MIS8 assignment. However if Red Barnes and Brooksfield North are MIS9, it is unlikely that Harnham is MIS10. The other site Brighton, Civic Centre, has only one species (Littorina) which we have not worked with before. The values for Gix and Asx are higher than other marine species (believed to be MIS7), but the values for Ala are lower. Given this variation it is not safe to make an assignment for this species.
|English Heritage Centre for Archaeology
- Amino-acid Racemisation
- Animal Remains