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1 School of Biological and Earth Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK bessgonz{at}livjm.ac.uk
2 Department of Geography, Science Laboratories, The University of Durham, South Road, Durham DH1 3LE, UK
3 School of Education, Community and Social Science, Liverpool John Moores University, I. M. Marsh Campus, Liverpool L17 6BD, UK
4 Centre for Manx Studies, 6 Kingswood Grove, Douglas, Isle of Man IM1 3LX, UK
5 Department of Geography, The University of Liverpool, P.O. Box 147, Liverpool L69 3BX, UK
New multidisciplinary work at Phurt in the north of the Isle of Man using stratigraphy, radiocarbon dating, pollen, diatoms, foraminifera and archaeology has reevaluated the sedimentological and archaeological sequence located in a series of basins containing organic peats, silts and sands at the south end of the Flandrian Ayres raised beach succession. From this work it is clear that all the Mesolithic finds from the beach have been reworked and are not significant in terms of human occupation in this area and there is no evidence for human modification of the Mesolithic vegetation from Phurt. The radiocarbon dates for the middle peat fit into the Neolithic phase and although all the in situ artifacts are from layers above the peat from a sandy palaeosol, these layers are likely to have been deposited rapidly after the peat formation. Although the artifacts are Middle Neolithic in typology it is considered that the dates from the peat are not inconsistent with the archaeological dating framework.
The pollen indicates an early woodland phase but there are indicators of the close proximity of the sea from coastal pollen taxa, foram test linings in the upper peat layer and diatoms. In the middle peat tree pollen was much less frequent, there was a wide range of open ground herb taxa, mainly of freshwater type but again there were salt marsh taxa present, indicating the close proximity of the sea. In the upper organic horizon and the burnt mound profiles the lack of coastal pollen must indicate a relative sea-level drop. The depositional environment envisaged to account for the litho- and pollen stratigraphy in these small basins is predominantly a freshwater lake behind shingle bars, with the close proximity to seaward of a saltmarsh. On occasions there must have been brackish water in these lagoons and a marine connection through the shingle barrier based on the diatom evidence, which is similar to the interpretation at nearby Lough Cranstal. This is in contrast with the Liverpool Bay sequences where there is evidence for several marine transgressions, but in both areas the coastal or near coastal environments indicate much well preserved evidence for Neolithic and Bronze Age occupation and vegetational alteration by these populations.
