Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-27T22:16:33.541Z Has data issue: false hasContentIssue false

Radiocarbon Dating Wooden Carvings and Skeletal Remains from Pitch Lake, Trinidad

Published online by Cambridge University Press:  31 October 2017

Fiona Brock*
Affiliation:
Cranfield Forensic Institute, Cranfield University, Defence Academy of the United Kingdom, Shrivenham, Oxon, SN6 8LA, United Kingdom
Joanna Ostapkowicz
Affiliation:
World Museum, National Museums Liverpool, William Brown Street, Liverpool, L3 8EN, United Kingdom School of Archaeology, University of Oxford, 36 Beaumont Street, Oxford, OX1 2PG, United Kingdom
Alex C Wiedenhoeft
Affiliation:
Center for Wood Anatomy Research, Forest Products Laboratory, One Gifford Pinchot Drive, Madison, WI, 53726USA
Ian D Bull
Affiliation:
Organic Geochemistry Unit, School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
*
*Corresponding author. Email: f.brock@cranfield.ac.uk.

Abstract

Since the mid-19th century, rare prehistoric wooden carvings and human skeletal remains have been dredged from Pitch Lake, Trinidad, during commercial asphalt mining. Establishing a chronology for these objects is challenging, due to both a lack of stratigraphic and contextual information and the necessity to completely remove any pitch to ensure accurate radiocarbon (14C) dates. A range of solvent extraction protocols was tested to identify the most suitable one for pretreating the Pitch Lake artifacts, and then applied to ten wooden objects and a human cranium recovered from the lake. Several of these objects yielded earlier dates than expected, raising concerns that pitch had remained after pretreatment and had affected the dates. Pyrolysis-GC/MS and optical microscopy techniques were applied to material from the human cranium, a weaving tool, and a small bowl. These techniques, as well as routinely applied laboratory quality assurance procedures, indicated that there was no residual pitch within the cranium or the weaving tool after pretreatment, giving confidence to the dates. However, the small bowl was observed to still be contaminated with pitch after extensive pretreatment, indicating that the date is too old and can only be considered as a terminus post quem.

Type
Method Development
Copyright
© 2017 by the Arizona Board of Regents on behalf of the University of Arizona 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Selected Papers from the 8th Radiocarbon & Archaeology Symposium, Edinburgh, UK, 27 June–1 July 2016

References

REFERENCES

Ambrose, SH. 1990. Preparation and characterization of bone and tooth collagen for isotopic analysis. Journal of Archaeological Science 17(4):431451.Google Scholar
Atwooll, AW, Broome, DC. 1954. Trinidad Lake Asphalt. 2nd revised edition. London: The Baynard Press.Google Scholar
Aufderheide, AC, Nissenbaum, A, Cartmell, L. 2004. Radiocarbon date recovery from bitumen-containing Egyptian embalming resins. JSSEA 31:8796.Google Scholar
Boomert, A. 1984. The Pitch Lake in History. Naturalist 5(11):2127.Google Scholar
Boomert, A, Harris, PO. 1984. The Pitch Lake in Archaeology. Naturalist 5(11):3445.Google Scholar
Brock, F, Bronk Ramsey, C, Higham, T. 2007. Quality assurance of ultrafiltered bone dating. Radiocarbon 49(2):187192.Google Scholar
Brock, F, Higham, T, Ditchfield, P, Bronk Ramsey, C. 2010. Current pretreatment methods for AMS radiocarbon dating at the Oxford Radiocarbon Accelerator Unit (ORAU). Radiocarbon 52(1):103112.Google Scholar
Coltrain, JB, Harris, JM, Cerling, TE, Ehleringer, JR, Dearing, M-D, Ward, J, Allen, J. 2004. Rancho La Brea stable isotope biogeochemistry and its implications for the palaeoecology of late Pleistocene, coastal southern California. Palaeogeography, Palaeoclimatology, Palaeoecology 205:199219.Google Scholar
Dee, MW, Brock, F, Bowles, AD, Bronk Ramsey, C. 2011. Using a silica substrate to monitor the effectiveness of radiocarbon pretreatment. Radiocarbon 53(4):705711.Google Scholar
Flournoy, DS, Kirk, TK, Highley, TL. 1991. Wood decay by brown-rot fungi: changes in pore structure and cell wall volume. Holzforshung 45(5):383388.Google Scholar
Fox-Dobbs, K, Stidham, TA, Bowen, GJ, Emslie, SD, Koch, PL. 2006. Dietary controls on extinction versus survival among avian megafauna in the late Pleistocene. Geology 34(8):685688.Google Scholar
Friscia, AR, Van Valkenburgh, B, Spencer, L, Harris, J. 2008. Chronology and spatial distribution of large mammal bones in pit 91, Rancho la Brea. Palaios 23(1/2):3542.Google Scholar
Fuller, BT, Fahrni, SM, Harris, JM, Aisling, BF, Coltrain, JB, Gerhart, LM, Ward, JK, Taylor, RE, Southon, JR. 2014. Ultrafiltration for asphalt removal from bone collagen for radiocarbon dating and isotopic analysis of Pleistocene fauna at the tar pits of Rancho La Brea, Los Angeles, California. Quaternary Geochronology 22:8598.Google Scholar
Fuller, BT, Harris, JM, Farrell, AB, Takeuchi, G, Southon, JR. 2015. Sample preparation for radiocarbon dating and isotopic analysis of bone from Rancho La Brea. Science Series 42:151167 Natural History Museum of Los Angeles County.Google Scholar
Fuller, BT, Southon, JR, Fahrni, SM, Harris, JM, Farrell, AB, Takeuchi, GT, Nehlich, O, Richards, MP, Guiry, EJ, Taylor, RE. 2016. No evidence of domestic dog burial with “La Brea Woman”. PaleoAmerica 2:5659.Google Scholar
Ho, TY, Marcus, LF, Berger, R. 1969. Radiocarbon dating of petroleum-impregnated bone from tar pits at Rancho La Brea, California. Science 164(3883):10511052.Google Scholar
Languri, GM, van der Horst, J, Boon, JJ. 2002. Characterisation of a unique “asphalt” samples from the early 19th century Hafkenscheid painting materials collection by analytical pyrolysis MS and GC/MS. Journal of Analytical and Applied Pyrolysis 63(1):171196.Google Scholar
Longin, R. 1971. New method of collagen extraction for radiocarbon dating. Nature 230:241242.Google Scholar
Newson, LA. 1976. Aboriginal and Spanish Colonial Trinidad: A Study in Culture Contact. London: Academic Press.Google Scholar
O’Keefe, FR, Fet, EV, Harris, JM. 2009. Compilation, calibration, and synthesis of fauna and floral radiocarbon dates, Rancho La Brea, California. Contributions in Science 518:116.CrossRefGoogle Scholar
Ostapkowicz, J, Bronk Ramsey, C, Brock, F, Higham, T, Wiedenhoeft, AC, Ribechini, E, Lucejko, JJ, Wilson, S. 2012. Chronologies in wood and resin: AMS 14C dating of pre-Hispanic Caribbean wood sculpture. Journal of Archaeological Science 39:22382251.Google Scholar
Ostapkowicz, J, Brock, F, Weidenhoeft, AC, Snoeck, C, Pouncett, J, Baksh-Comeau, Y, Schulting, R, Claevs, P, Mattielli, N, Richards, M, Boomert, A. (In press). Black pitch, carved histories: radiocarbon dating, wood species identification and strontium isotope analysis of prehistoric wood carvings from Trinidad’s Pitch Lake. Journal of Archaeological Science Reports.Google Scholar
Quiles, A, Delqué-Količ, E, Bellot-Gurlet, L, Comby-Zerbino, C, Ménager, M, Paris, C, Souprayen, C, Vieillescazes, C, Andreu-Lanoë, G, Madrigal, K. 2014. Embalming as a source of contamination for radiocarbon dating of Egyptian mummies: on a new chemical protocol to extract bitumen. ArchaeoSciences, revue d’archéométrie 38:135149.Google Scholar
Staff, RA, Reynard, L, Brock, F, Bronk Ramsey, C. 2014. Wood pretreatment protocols and measurement of tree-ring standards at the Oxford Radiocarbon Accelerator Unit (ORAU). Radiocarbon 56(2):709715.Google Scholar
Stafford, TW Jr, Hare, PE, Currie, L, Jull, AJT, Donahue, DJ. 1991. Accelerator radiocarbon dating at the molecular level. Journal of Archaeological Science 18:3572.Google Scholar
Ward, JK, Harris, JM, Cerling, TE, Wiedenhoeft, A, Lott, MJ, Dearing, M-D, Coltrain, JB, Ehleringer, JR. 2005. Carbon starvation in glacial trees recovered from the La Brea tar pits, southern California. PNAS 102(3):690694.Google Scholar
Whitehead, N. 1997. The Discoverie of the Large, Rich and Bewtiful Empyre of Guiana. Transcribed, annoted, and introduced by Whitehead NL. Manchester: Manchester University Press.Google Scholar
Wiltshire, WW. 2007. The Commercial Development of Trinidad Lake Asphalt. Laventille: SCRIP-J Printers, Ltd.Google Scholar