Style, Chauvet and radiocarbon. (Method).

Style, Chauvet and radiocarbon. (Method). On Candamo In the case of LSCE at least, it is not surprising that the twodates obtained from Candamo were the same, since they were obtained fromthe same (mixed) sample. One way to explain the age discrepancy betweenLSCE and Geochron is to assume that the charcoal dated in the USAoriginated in a 15 000-year-old tree whereas the charcoal dated inFrance had its origins in a tree felled more than 15 000 years earlier.Another possibility is that pollution might have affected certainsamples and not others. After all, there is absolutely no evidence thatthe samples analysed by M. Hoyos, or dated at Gif And in the US, comefrom pigment of similar age and type. Not only were the samplescollected at different spots and several years apart, but since we knowthat the Candamo cave has long been open to visitors, pollution is afactor to be considered. On the other hand, since dates ranging from 12000 to 22 000 (LSCE, unpublished results) were obtained for some otherfigures (also sampled by Pr. Fortea-Perez) from the same Candamo panel,this strongly suggest that this cave may have been visited at differentperiods by prehistoric people and that some black pigments are a mixtureof charcoal of different ages, or that some of these pigments may havebeen contaminated by exogenous carbon. All of this shows that thedecoration of this cave is rather complex and that no systematicoverestimation of the [sup.14]C ages should be imputed Attributed vicariously.In the legal sense, the term imputed is used to describe an action, fact, or quality, the knowledge of which is charged to an individual based upon the actions of another for whom the individual is responsible rather than on the individual's to the LSCE. Itis not valid to use the Candamo ages as a litmus test litmus testn.A test for chemical acidity or basicity using litmus paper. for thereliability of radiocarbon dating of prehistoric cave paintings ingeneral. The results obtained by either LSCE or Geochron from Candamomay prove to be anomalous, but that has no bearing on Chauvet. On the date of Chauvet When the discovery of the Chauvet Cave The Chauvet Cave or Chauvet-Pont-d'Arc Cave is located at N 44�� 21' and E 4�� 29' 24", near Vallon-Pont-d'Arc, in the Ard��che d��partement, in southern France. It became famous in 1994 when a trio of speleologists found that it contained the fossilized remains of many animals, was announced and itsinitial dates were published in 1995 (Clottes et al. 1995), we naturallyapplied the necessary caution: `Only when a date can be confirmed bydifferent methods should it be considered valid' (Clottes 1993:21). In support of a date in the Aurignacian, about 30 000 years BP, wenoted the following points: * the originality of the themes and techniques in Chauvet make itdifficult to use stylistic criteria to date the cave art cave art:see Paleolithic art; rock carvings and paintings. ; * the sophistication so��phis��ti��cate?v. so��phis��ti��cat��ed, so��phis��ti��cat��ing, so��phis��ti��catesv.tr.1. To cause to become less natural, especially to make less naive and more worldly.2. of the art in Chauvet was remarkable, butcould be compared to that of the portable art in the Swabian Jura, whereivory statuettes had long been found in Aurignacian layers; * the animals represented on those statuettes (and on otherAurignacian sites in the Dordogne) recalled the abundant presence ofanimal species in Chauvet which become rare in French Gravettian andlater art (Clottes et al. 1995; Clottes 1996a; 1996b; 2001). * the similarity of themes and techniques used for the black, redor engraved animals did not allow us to distinguish different periods inthe art; * torch marks superimposed on a film of calcite calcite(kăl`sīt), very widely distributed mineral, commonly white or colorless, but appearing in a great variety of colors owing to impurities. covering earlieranimal images were dated to around 26 000 BP, a result corroborated byfurther torch mark analyses in another chamber: the parietal parietal/pa��ri��e��tal/ (pah-ri��e-t'l)1. of or pertaining to the walls of a cavity.2. pertaining to or located near the parietal bone.pa��ri��e��taladj.1. stratigraphy stratigraphy,branch of geology specifically concerned with the arrangement of layered rocks (see stratification). Stratigraphy is based on the law of superposition, which states that in a normal sequence of rock layers the youngest is on top and the oldest on the was thus consistent. All these facts and their consequences, despite stylistic argumentshaving early been expressed against them (Zuchner 1996), have beenendorsed by Bahn: "If just one date of 30,000 had been obtained forthe Grotte Chauvet in France, no one would have believed the result; itwas the series of dates, together with the later figures obtained fortorch marks on top of the calcite covering the art, which convincedeveryone despite the universal amazement" (Bahn & Vertut 1997:76) and "The early dates tally well with the sophisticated portableimagery known, from portable art in this period in south-west Germanyand elsewhere in France" (Bahn 1998: 164). In fact, if those earlydates "have caused surprise, this has been due to imperfectknowledge of the age of certain conventions in drawing or to anunhealthy reliance on Leroi-Gourhan's chronological sequence Noun 1. chronological sequence - a following of one thing after another in time; "the doctor saw a sequence of patients"chronological succession, succession, successiveness, sequencetemporal arrangement, temporal order - arrangement of events in time offour successive styles, which had always incorporated some majorimperfection--most notably in its ignoring the great age (more than 30000 years) of the sophisticated portable carvings of south-westGermany" (Bahn 1998: 168-9). The originality of Chauvet--whichmakes stylistic comparisons dubious at best--has been frequentlyrestated (Bahn & Vertut 1997: 153, 157, 191), as well as thespecific attribution of its art to the Aurignacian (Bahn & Vertut1997: 121, 140, 157, 206). Since our own initial publications, the work of the Chauvet team(Clottes 2001) has about doubled the number of animal figures known andhas more than trebled the number of radiocarbon dates. From this pointof view, the Chauvet Cave is the best-dated rock art site in the world.We have determined c. 40 dates, 10 obtained for pigments from cavedrawings and torch rubbings, the rest from charcoal found in abundanceon the ground (Valladas et al. 2001). The great majority can be groupedinto two tight clusters representing two time-periods a few thousands ofyears apart (32 500 - 30 000 and 27 000 - 26 000 years BP respectively).If the samples had been seriously contaminated, we feel that the rangeof dates would have been more scattered. Such consistent results can beattributed to the great number of samples available for dating and tothe fact that the cave was sealed by a rock-fall very early on and wasnot revisited until a few years ago (in contrast to Candamo). Since itsdiscovery every precaution has been taken to avoid pollution, a taskfacilitated by the fact that it is closed to the public. Zuchner's arguments (1996, 1999) are based on long-distancecomparisons and imply that stylistic characteristics are what used to becalled `type-fossils'. For this to be true, we should have tosuppose we definitely know the first time when such a technique or sucha theme was used, its precise duration and geographical spread (Clottes1996a; 2001: 213-14). This is far from being the case. He explains whathe sees as `discrepancies between radiocarbon and archaeologicaldates' (Zuchner 1996: 26) by the idea that `Magdalenian artistscollected fossil wood' or picked up charcoal made on the ground byprevious artists (Zuchner 1996: 26). But this runs against establishedfacts. We would have to suppose that all the directly dated animalfigures had been drawn with fossil wood Fossil wood is wood that is preserved in the fossil record. Over time the wood will usually be the part of a plant that is best preserved (and most easily found). Fossil wood may or may not be petrified. dated to more than 30 000 BPwhile a slightly later fossil wood (26-27 000 BP) was chosen for thetorches (Clottes 1996; 2001). All this is difficult to believe. The main arguments advanced by Pettitt and Bahn are now in the lineof Zuchner's and presuppose pre��sup��pose?tr.v. pre��sup��posed, pre��sup��pos��ing, pre��sup��pos��es1. To believe or suppose in advance.2. To require or involve necessarily as an antecedent condition. See Synonyms at presume. a fixed duration for some techniques,themes and conventions. That this is a dangerous way of reasoning isevidenced by what they say about the "engraved tectiform",called "another classic Magdalenian phenomenon". To quote justone example, we know several identical geometric signs in the CosquerCave The Cosquer cave is located in the Calanque de Morgiou near Marseille, France, not very far from Cap Morgiou. This cave, the entrance of which is located underwater nowadays, was discovered by Henri Cosquer in 1991. where the numerous radiocarbon dates have evidenced two mainperiods (one around 19 000 BP, the other around 27 000 BP), i.e. bothmuch earlier than the Magdalenian. On radiocarbon procedures The experimental protocols used at the Laboratoire ales Sciences duClimat et de l'Environnement (LSCE) have been published (Valladaset al. 1999; 2001) and we see no need to restate them here. We invitereaders to note the following points. First, dates from the humic acid Noun 1. humic acid - a dark brown humic substance that is soluble in water only at pH values greater than 2; "the half-life of humic acid is measured in centuries"humic substance - an organic residue of decaying organic matter fraction need not be unacceptable. In a comprehensive article thatcompared numerous dates obtained on charcoal and humic acid from thesame samples, Batten et al. (1986) concluded that the "`humic'acid dates can be reliable in a surprisingly frequent number ofsituations" and also noted that in some cases where the charcoaldate is younger, the associated humic acid fraction `relates moreclosely to the context of the sample'. But it is obvious that anygeneralizations are fraught with dangers and each case should beevaluated on the basis of properties specific to the sample. We have actually found the older dates for a given sample morereliable because of the permanent risk of contamination byrecently-deposited carbon and consequent age-reduction. Exposed pigmentscan be polluted by later organic materials, some of which can resist thechemical treatment meant to eliminate them. Some samples are so smalland fragile that a sufficiently rigorous pre-treatment can dissolve thetarget material too. In such cases the humic acid fraction, whichconsists in part of original charcoal which had been dissolved in analkaline environment and re-precipitated, will give a more nearlycorrect greater age. For this reason we retained the older humic aciddates in some samples from both Altamira and Chauvet. We are fully aware that no individual and no technique can claiminfallibility and despite the best of intentions things can go wrong,but all anomalous results have an explanation. It is certainly right toinsist on corroboration of dates through scientific co-operation. In themany years since the Chauvet cave was discovered, the LSCE atGif-sur-Yvette has participated in international inter-laboratorycomparison studies and determined thousands of dates for numerous sitesof different periods. Any tendency of our methodology to systematicallyover-estimate dates would have come to light a long time ago. Whatshould be stressed is the need to make sure that the materials submittedto different dating laboratories are aliquots of the same homogeneoussample. References BAHN, P.G. 1998. The Cambridge illustrated history of prehistoricart The perspective and/or examples in this article do not represent a world-wide view. Please [ edit] this page to improve its geographical balance. . Cambridge: Cambridge University Press Cambridge University Press (known colloquially as CUP) is a publisher given a Royal Charter by Henry VIII in 1534, and one of the two privileged presses (the other being Oxford University Press). BAHN, P.G. & J. VERTUT. 1997. Journey through the Ice Age.London: Weidenfeld & Nicolson. BATTES, R.J., R. GILLESPIE, J.A.J. GOWLETT & R.E.M. HEDGES.1986. The AMS AMS - Andrew Message System dating of separate fractions in Archaeology, Radiocarbon28, 2A: 698-701. CLOTTES, J. 1996a. The Chauvet Cave dates implausible?International Newsletter on Rock Art 13: 27-9. --1996b. Thematic changes in Upper Palaeolithic art: a view fromthe Grotte Chauvet, Antiquity 70: 276-88. --1999. The Chauvet Cave dates, in A.F. Harding (ed.), Experimentand design. Archaeological studies in honour of John Coles: 13-19.Oxford: Oxbow. --(Ed.). 2001. La Grotte Chauvet. L'art des origines. Paris:Seuil. CLOTTES, J., J.-M. CHAUVET, E. BRUNEL-DESCHAMPS, C. HILLAIRE, J.-P.DAUGAS, M. ARNOLD, H. CACHIER, J. EVIN, P. FORTIN, C. OBERLIN, N.TISNERAT & H. VALLADAS. 1995. Les peintures paleolithiques de lagrotte Chauvet-Pont d'Arc (Ardeche, France): datations directes etindirectes par la methode du radiocarbone, Comptes rendus del'Academie des Sciences de Paris 320 (series IIa): 1133-40. CLOTTES, J., B. GELY & Y. LE GUILLOU. 1999b. Complementaryiconographic information from the Chauvet Cave, International Newsletteron Rock Art 24: 4-8. HEDGES, R.E.M., I.A. Law, C.R. BRONKS & R.A. HOUSLEY. 1989. TheOxford accelerator mass spectrometry accelerator mass spectrometryn.Mass spectroscopy in which a particle accelerator is used to disassociate molecules, ionize atoms, and accelerate the ions. facility: technical developments inroutine dating, Archaeometry 31: 99-113. LORBLANCHET, M. & P.G. BAHN. 1991. Rock art studies: thepost-stylistic era. Where do we go from here? Rock Art Research 8: 65. --1993. Introduction, in M. Lorblanchet & P.G. Bahn (ed.), Rockart studies: the post-stylistic era. Where do we go from here?: v-viii.Oxford: Oxbow. Monograph 35. VALLADAS, H., J. CLOTTES, J.M. GENESTE, M. GARCIA, M. ARNOLD, H.CACHIER & N. TISNERAT-LABORDE. 2001. Evolution of prehistoric caveart, Nature 413: 479. VALLADAS, H., N. TISNERAT, H. CACHIER & M. ARNOLD. 1999.Datation directe des peintures prehistoriques par la methode du carbone14 en spectrometrie de masse par accelerateur, Supplement 1999 de laRevue d'Archeometrie. 39-44. VALLADAS, H., N. TISNERAT-LABORDE, H. CACHIER, M. ARNOLD, F.BERNALDO DE QUIROS, V. CABRERA-VALDES, J. CLOTTES, J. COURTIN, J.FORTEA-PEREZ, C. GONZALES-SAINZ & A. MOURE-ROMANILLO. 2001.Radiocarbon AMS dates for Paleolithic cave paintings, Radiocarbon 43,2B: 977-86. ZUCHNER, C. 1996. The Chauvet Cave. Radiocarbon versus Archaeology.International Newletter on Rock Art 13: 25-7. --1999. La cueva Chauvet, datada arqueologicamente, Edades, Revistade Historia 6: 167-85. Helene Valladas & Jean Clottes * * Clottes, Conservateur general du Patrimoine, 11 rue du Fourcat,09000 Foix, France. * Valladas, Laboratoire des Sciences du Climat et del'Environnement, UMR UMR Unite Mixte de Recherche (French: Mixed Unit of Research )UMR University of Missouri - RollaUMR Upper Mississippi RiverUMR Uniform Methods and Rules (US Department of Agriculture)UMR Unit Manning Report CEA-CNRS, Batiment 12, Avenue de la Terrasse La Terrasse is a commune in France, located in the d��partement of Is��re and the r��gion of Rh?ne-Alpes. Its residents are known as Terrassons.Coordinates: ,91198 Gif-sur-Yvette Cedex, France. Received 29 May 2002; Revised 2 September 2002; Accepted 3 January2003.