69 Newgate Street, Bishop Auckland, Durham: Tree-ring Analysis and Radiocarbon Wiggle-matching of Pine Timbers
Author(s): Alison Arnold, Robert Howard, Cathy Tyers, Dana Challinor, Bisserka Gaydarska, Michael Dee
Tree-ring analysis was undertaken on 10 of the 12 samples obtained from the pine timbers to this roof. This analysis produced two site chronologies. The first site chronology (BSAASQ01) comprises seven samples and is 74 rings long overall, the second site chronology (BSAASQ02) comprises two samples and is 96 rings long overall. Although compared to an extensive body of reference data for pine, neither site chronology was considered conclusively dated by dendrochronology. The single remaining measured but ungrouped sample was also compared to the reference chronologies for pine, but again no secure dating was identified. Radiocarbon dating was undertaken on nine single-ring samples from two timbers represented in the tentatively dated site master chronologies. Wiggle-matching of these results suggests that the final ring of site master sequence BSAASQ01, formed in cal AD 1744–1757 (58% probability) or cal AD 1931–1945 (37% probability), while the final ring of site master sequence BSAASQ02 formed in cal AD 1742–1760 (59% probability), or cal AD 1855–1891 (30% probability), or cal AD 1930–1946 (6% probability). The tentative cross-matching identified for the site master chronologies by ring-width dendrochronology is thus supported independently by the radiocarbon wiggle-matching, allowing dating of BSAASQ01 to be accepted when it spans AD 1676–1749DR and dating of BSAASQ02 to be accepted when it spans AD 1655–1750 DR. The nine dated timbers are clearly coeval, but the wide variation in numbers of sapwood rings across Scandinavia means that it is not possible to estimate a felling date range for these timbers. Allowing for the missing sapwood, however, it is possible to suggest that the timbers used in the roof were felled in the latter half of the eighteenth century or possibly in the early nineteenth century.
- Report Number:
- 35/2024
- Series:
- Research Report
- Pages:
- 50
- Keywords:
- Dendrochronology Wiggle-Match Scientific Dating
