Alkali extraction of archaeological and geological charcoal: evidence for diagenetic degradation and formation of humic acids

Charcoal forms a crucial source of archaeological and palaeoenvironmental data, providing a record of cultural activities, past climatic conditions and a means of chronological control via radiocarbon (¹⁴C) dating. Key to this is the perceived resistance of charcoal to post-depositional alteration, however recent research has highlighted the possibility for alteration and degradation of charcoal in the environment. An important aspect of such diagenesis is the potential for addition of exogenous “humic acids’ (HAs), to affect the accuracy of archaeological and palaeoenvironmental reconstructions based upon chemical analyses of HA-containing charcoal. However the release of significant quantities of HA from apparently pristine charcoals raises the question whether some HA could be derived via diagenetic alteration of charcoal itself. Here we address this question through comparison of freshly produced charcoal with samples from archaeological and geological sites exposed to environmental conditions for millennia using elemental (C/H/O) and isotopic (δ¹³C) measurements, Fourier Transform Infrared Spectroscopy (FTIR) and proton Liquid-State Nuclear Magnetic Resonance (¹H NMR). The results of analyses show that the presence of highly carboxylated and aromatic alkali-extractable HA in charcoal from depositional environments can often be attributable to the effects of post-depositional processes, and that these substances can represent the products of post-depositional diagenetic alteration in charcoal.     

Stable Carbon and Nitrogen Isotope Variability of Bone Collagen to Determine the Number of Isotopically Distinct Specimens

Journal of Archaeological Method and Theory - Archaeological and palaeontological excavations frequently produce large quantities of highly fragmentary bone. These bones can help to answer...     

London’s Olympic waterscape: capturing transition

The waterways of London are an essential component of the city, with the River Thames playing a prominent role in the heritage, history and identity of place. The upcoming 2012 Olympics are highlighting the Lea Valley waterways in east London as another important part of London’s waterscape, expanding London’s global presence as a ‘water city’. As part of the Creative Campus Initiative, we undertook a project based on the broad themes of water, London and the Olympics that would give voice to the changes taking place. The result is London’s Olympic Waterscape, a 20-minute film comprising both ‘expert’ interview material discussing broad themes and developments and an embodied record of our engagement with the Olympic area during a brief period in the construction process. The present article is about the journey we took through and around the east London ‘Olympic’ waterways as we attempted to capture this transitional moment on video.     

Reviews

Joseph Rykwert, The Dancing Column. On Order in Architecture, Cambridge, Mass. and London: The MIT Press, 1996. xviii + 598 pp., 316 b. & w. illus. ISBN 0–262–18170–3. £49.95.

Janet Lang and Andrew Middleton (eds.), Radiography of Cultural Material, Oxford: Butterworth‐Heinemann, 1997. xii + 193 pp., 23 col. and 157 b. & w. illus. ISBN 0–7506–2621–6. £45.00.

Chris Rojek and John Urry (eds.), Touring Cultures: Transformations of Travel and Theory, London and New York: Routledge, 1997. x + 214 pp., 11 b. & w. illus. and 1 fig. ISBN 0–415–111225–0. £13.99.

Peter Mandler, The Fall and Rise of the Stately Home, New Haven and London: Yale University Press, 1997. viii + 523 pp., 99 b. & w. illus. ISBN 0–300–06703–8. £19.95.

Susan M. Pearce (ed.), Experiencing Material Culture in the Western World, London and Washington: Leicester University Press, 1997. xiv + 274 pp., 1 b. & w. illus. ISBN 9–7185–0022–9. £18–99.

Steven Parissien, Station to Station, London: Phaidon, 1997. 240 pp., 191 col. and 146 b. & w. illus. ISBN 0–7148–3467‐X. £39.99.

David Phillips, Exhibiting Authenticity, Manchester and New York: Manchester University Press, 1997. xi + 234 pp., 61 b. & w. illus. ISBN 0–7190–4797–8. £16.99.

Phillip Lindley (ed.), Sculpture Conservation: Preservation or Interference?, Aldershot, England: Scolar Press, 1997. xxxii + 237 pp., 18 figs., 97 b. & w. and 65 col. illus. ISBN 1–85928–254–7. £35.00.

George (Rip) Rapp Jr. and Christopher L. Hill, Geoarchaeology: the Earth‐science Approach to Archaeological Interpretation, New Haven and London: Yale University Press, 1998. xiii + 274 pp., 80 figs. ISBN 0–300–07075–6. £28.00.

Brian J. Shaw and Roy Jones (eds.), Contested Urban Heritage: Voices from the Periphery, Aldershot, Brookfield USA, Singapore, Sydney: Ashgate, 1997. ix + 205 pp., 19 figs, 42 b. & w. illus. ISBN 1–85972–554–6. £37.50.

Dianne Sachko Macleod, Art and the Victorian Middle Class: Money and the Making of Cultural Identity, Cambridge: Cambridge University Press, 1996. xx + 530 pp., 8 col. and 76 b. & w. illns. ISBN 0–521–55090–4. £65.00.

Nicholas Barton, Stone Age Britain, London: B. T. Batsford in association with English Heritage, 1997. 144 pp., 7 figs., 16 col. and 113 b. & w. illus. ISBN 0–7134–6846–7. £15.99.

Paul Bidwell, Roman Forts in Britain, London: B. T. Batsford in association with English Heritage, 1997. 128 pp., 12 col. and 80 b. & w. illus. ISBN 0–7134–7100‐X. £15.99.

Peter Marsden, Ships and Shipwrecks, London: B. T. Batsford in association with English Heritage, 1997. 128 pp., 11 col. and 85 b. & w. illus. ISBN 0–7134–7536–6. £15.99.

Trevor Rowley, Norman England, London: B. T. Batsford in association with English Heritage, 1997. 144 pp., 12 col. and 94 b. & w. illus. ISBN 0–7134–8060–2. £15.99.     

The use of OSL dating in unstructured sands: the archaeology and chronology of the Hutton Sands at Canteen Kopje (Northern Cape Province, South Africa)

Archaeological research at the site of Canteen Kopje, Northern Cape Province, South Africa, has focused on the rich Earlier Stone Age assemblages recovered from the Younger Vaal Gravels. This paper presents the results of excavation and optically stimulated luminescence (OSL) dating of the overlying Hutton Sands. We discuss the evidence for colonial period interaction between diamond miners and indigenous groups at the site, as well as the presence of an earlier phase of terminal Middle Stone Age/early Later Stone Age occupation. The OSL analyses demonstrate the potential distortion of OSL ages due to substantial bioturbation and its effect on the dating of archaeological sites situated in unconsolidated sands.