Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-22T23:51:52.387Z Has data issue: false hasContentIssue false

Marine Radiocarbon Reservoir Effect in Southern Atlantic Iberian Coast

Published online by Cambridge University Press:  09 February 2016

José M Matos Martins*
Affiliation:
Laboratório de Radiocarbono, Campus Tecnológico e Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, ao km 139,7, 2695-066 Bobadela LRS, Portugal Faculdade de Ciências e Tecnologia, CIMA, Universidade do Algarve Campus de Gambelas, 8005-139 Faro, Portugal
António M Monge Soares
Affiliation:
Laboratório de Radiocarbono, Campus Tecnológico e Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, ao km 139,7, 2695-066 Bobadela LRS, Portugal
*
Corresponding author. Email: [email protected].

Abstract

Research concerning the variability of the marine radiocarbon reservoir effect (ΔR) in the southern Iberian Atlantic coast confirms the existence of different ΔR values for regions that correspond to different oceanographic conditions. Due to these oceanographic conditions, the southern Iberian Atlantic coast can be divided into 3 zones: the Barlavento (windward), where the coastal waters are influenced by an intense upwelling of the northeastern Atlantic circulation (positive ΔR values); the Sotavento (leeward), where an upwelling area of minor intensity occurs; and the Andalusian coast, where because of its configuration does not present any wind-driven coastal upwelling (negative ΔR values). For the first time, ΔR values were determined for the Sotavento coastal region and, at the same time, new ΔR values were calculated for the Barlavento and the Andalusian coast for the last 3000 yr taking into account the data already obtained but now using a new methodology for calculation. In this way, ΔR weighted mean values were determined for the 3 regions of the southern Iberian Atlantic coast: ΔR = +69 ± 17 14C yr (Barlavento), ΔR = −26 ± 14 14C yr (Sotavento), and ΔR = −108 ± 31 14C yr (Andalusian coast). These values are in accordance with the different oceanographic conditions prevailing in these coastal regions. The data also allow identification of a Bond event at 0.8 ka cal BP and a drastic change in the oceanographic conditions in the Barlavento and Andalusian coastal areas during the 5th millennium cal BP.

Type
Radiocarbon Reservoir Effects
Copyright
Copyright © 2013 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.)

References

Arruda, AM, Soares, AMM, Freitas, VT, Oliveira, CF, Martins, JMM, Portela, PC. In press. A cronologia relativa e absoluta da ocupação Sidérica do Castelo e Castro Marim. XELB 12. In Portuguese.Google Scholar
Ascough, PL, Cook, GT, Dugmore, AJ. 2005. Methodological approaches to determining the marine radiocarbon reservoir effect. Progress in Physical Geography 29(4):532–47.Google Scholar
Ascough, PL, Cook, GT, Dugmore, AJ, Scott, EM. 2007. The North Atlantic marine reservoir effect in the Early Holocene: implications for defining and understanding MRE values. Nuclear Instruments and Methods in Physics B 259(1):438–47.Google Scholar
Ascough, PL, Cook, GT, Dugmore, AJ. 2009. North Atlantic marine 14C reservoir effects: implications for late-Holocene chronological studies. Quaternary Geochronology 4(3):171–80.Google Scholar
Bronk Ramsey, C. 2009. Bayesian analysis of radiocarbon dates. Radiocarbon 51(1):337–60.Google Scholar
deMenocal, PB, Ortiz, J, Guilderson, T, Sarnthein, M. 2000. Coherent high- and low-latitude climate variability during the Holocene warm period. Science 288(5474):2198–202.Google Scholar
Diffenbaugh, NS, Sloan, LC, Snyder, MA. 2003. Orbital suppression of wind-driven upwelling in the California Current at 6 ka. Paleoceanography 18:1051, doi:10.1029/2002PA000865.Google Scholar
Ferreira, DB. 1984. Le Systeme Climatique de l'Upwelling Ouest Iberique. [Report #19 of the Linha de Acção de Geografia Física], Lisbon: Centro de Estudos Geográficos. INIC. 92 p.Google Scholar
Fiúza, AFG. 1982. The Portuguese coastal upwelling system. In: Actual Problems of Oceanography in Portugal. Lisbon: Junta Nacional de Investigação Científica e Tecnológica. p 4571.Google Scholar
Fiúza, AFG. 1983. Upwelling patterns off Portugal. In: Suess, E, Thiede, J, editors. Coastal Upwelling. Its Sediment Record. New York: Plenum. p 8598.Google Scholar
Fiúza, AFG, Macedo, ME, Guerreiro, MR. 1982. Climatological space and time variation of the Portuguese coastal upwelling. Oceanologica Acta 5:3140.Google Scholar
Ingram, BL. 1998. Differences in radiocarbon age between shell and charcoal from a Holocene shellmound in northern California. Quaternary Research 49(1):102–10.Google Scholar
Kennett, DJ, Ingram, BL, Erlandson, JM, Walker, P. 1997. Evidence for temporal fluctuations in marine radiocarbon reservoir ages in the Santa Barbara Channel, southern California. Journal of Archaeological Science 24(11):1051–9.Google Scholar
Martins, JMM, Martín, AM, Portela, PJC, Soares, AMM. 2012. Improving the 14C dating of marine shells from the Canary Islands for constructing more reliable and accurate chronologies. Radiocarbon 54(3–4):943–52.Google Scholar
Reimer, PJ, McCormac, G, Moore, J, McCormick, F, Murray, EV. 2002. Marine radiocarbon reservoir corrections for the mid- to late Holocene in the eastern subpolar North Atlantic. The Holocene 12(2): 129–35.Google Scholar
Reimer, PJ, Baillie, MGL, Bard, E, Bayliss, A, Beck, JW, Blackwell, PG, Bronk Ramsey, C, Buck, CE, Burr, GS, Edwards, RL, Friedrich, M, Grootes, PM, Guilderson, TP, Hajdas, I, Heaton, T, Hogg, AG, Hughen, KA, Kaiser, KF, Kromer, B, McCormac, FG, Manning, SW, Reimer, RW, Richards, DA, Southon, JR, Talamo, S, Turney, CSM, van der Plicht, J, Weyhenmeyer, CE. 2009. IntCal09 and Marine09 radiocarbon age calibration curves, 0–50,000 years cal BP. Radiocarbon 51(4): 1111–50.Google Scholar
Rogerson, M, Rohling, EJ, Weaver, PPE, Murray, JW. 2004. The Azores Front since the Last Glacial Maximum. Earth and Planetary Science Letters 222(3–4):779–89.Google Scholar
Russell, N, Cook, GT, Ascough, PL, Scott, EM, Dugmore, AJ. 2011. Examining the inherent variability in ΔR: new methods of presenting ΔR values and implications for MRE studies. Radiocarbon 53(2):277–88.Google Scholar
Soares, AMM. 1989. O Efeito de Reservatório Oceânico nas Águas Costeiras de Portugal Continental. Sacavém: Instituto de Ciências e Engenharia Nucleares. Instituto Nacional de Engenharia e Tecnologia Industrial. 135 p. In Portuguese.Google Scholar
Soares, AMM. 1993. The 14C content of marine shells: evidence for variability in coastal upwelling off Portugal during the Holocene. In: Isotope Techniques in the Study of Past and Current Environmental Changes in the Hydrosphere and the Atmosphere. Vienna: IAEA. p 471–85.Google Scholar
Soares, AMM. 2005. Variabilidade do “Upwelling” Costeiro durante o Holocénico nas Margens Atlânticas Ocidental e Meridional da Península Ibérica [PhD dissertation]. Faro: Faculdade de Ciências do Mar e do Ambiente, Universidade do Algarve. In Portuguese.Google Scholar
Soares, AMM. 2010. Comment on “Formation of chenier plain of the Doñana marshland (SW Spain): Observations and geomorphic model” by A. Rodríguez-Ramírez and C.M. Yáñez-Camacho. [Marine Geology 254 (2008) 187–196]. Marine Geology 275(1–4):287–89.Google Scholar
Soares, AMM, Dias, JMA. 2006a. Coastal upwelling and radiocarbon—evidence for temporal fluctuations in ocean reservoir effect off Portugal during the Holocene. Radiocarbon 48(1):4560.Google Scholar
Soares, AMM, Dias, JMA. 2006b. Once upon a time…the Azores Front penetrated into the Gulf of Cadiz. In: Proceedings of the 5th Symposium on the Iberian Atlantic Margin. Aveiro: Universidade de Aveiro. p 205–6.Google Scholar
Soares, AMM, Dias, JMA. 2007. Reservoir effect of coastal waters off western and northwestern Galicia. Radiocarbon 49(2):925–36.Google Scholar
Soares, AMM, Martins, JMM. 2009. Radiocarbon dating of marine shell samples. The marine radiocarbon reservoir effect of coastal waters off Atlantic Iberia during Late Neolithic and Chalcolithic periods. Journal of Archaeological Science 36(12):2875–81.Google Scholar
Soares, AMM, Martins, JMM. 2010. Radiocarbon dating of marine samples from Gulf of Cadiz: the reservoir effect. Quaternary International 221(1–2):912.Google Scholar
Stuiver, M, Braziunas, TF. 1993. Modeling atmospheric 14C influences and 14C ages of marine samples to 10,000 BC. Radiocarbon 35(1):137–89.Google Scholar
Stuiver, M, Polach, HA. 1977. Discussion: reporting of 14C data. Radiocarbon 19(3):355–63.Google Scholar
Stuiver, M, Pearson, GW, Braziunas, T. 1986. Radiocarbon age calibration of marine samples back to 9000 cal yr BP. Radiocarbon 28(2B):9801021.Google Scholar
Vargas, JM, García-Lafuente, J, Delgado, J, Criado, F. 2003. Seasonal and wind-induced variability of sea surface temperature patterns in the Gulf of Cádiz. Journal of Marine Systems 38:205–19.Google Scholar