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Page 1: Strange results give rise to strange discussions

Strange results give rise to strange discussions

In iiiir paper Kutlroc~rrhuri ~ k r r i 1 i g (11 I ~ P C h i - F r t r r & i d

hwndirij, , I / i h t , . S w i h v h 7 i I l i e Si dt , . b) Lars Brunnberg and Gdraii Poisnert. in BOI-[MJ 21. X9 9h ( 1997) u e presented radioc;irbon h t e , of organic I prriostrdcuni) and inorganic (shell carbonate) fraction\ from I'orrimdrti ( YiildiiiJ (rr( L I

shells from 'I well-defined stratigraphic ldqer iii a v a n e d glacial cia! dated to 10.370 \ m e jsara RP Ih t ing results from a lish ykeleton f o u n d iii ;I correTponding clay \ a r \e time inrenal Mere also prcteritetl These dates were conipared H i t h existing calibr,ition ddca a, uell ac u.ith the Swedish cla! \ ;me t i m e scale

In the ~Iiscus~ion \be h a l e taken the reserroir d l e c t s into c o i i ~ i J c r a ~ ~ o ~ ~ The obtained radiocxbon ages ;ire compared both . r i t t i [he clay b a n e time scale m d \\ith similar nieawre- niencs reported from terrestrial material. Since the age of the carbiinate frdction i s higher t h m the cLi) \ a r \ e date. a snialler diferrnce \\ill q p c a r uhen a correction for thc re\ervoir etTect

i s applied An) reservoir cHect wi l l normally make the mea- sured dge higher than the 'real' one.

For thc organic materiiil [ periosti-acuni and fish skeleton). on the other hand. which i s younger than the clay varve date. a i q q u dr [ / t~ r~ ,11w wi l l be obtained when the reservoir effect is subtracted. We have to reduce the measured age with the correction f,ictor. which means that the discrepancies, instcad of 1000 )car\ which u e h a l e written (page 95, first column \econd paragraph). will be 2000 years. We regret this mistake and the confusion it may have caused the readers. Unfortu- natel) the comparison bet\\een dating methods and dated m;ite- rial in our piper no\\ conies out more unaspected than berim.

Lorr RI ri t i t i /wrq. D ipurr i~ i iw~ < I / Q i u ~ r ~ ~ r t i i r r v Rc.~eurv.h, Storhholtn 1 ; i i i . i , r511j . O i l e t t ~ ~ i i r i r n 6.7. S- 113 22 Stockholtn, Su~&n: Gbrirw P o , 51i~'rr. Tlic Srrdhr,x Lirhornrorj ' . L'tiii-o.sitr of L ~ J ~ s ~ u . 811.1-

. . . $ 7 i. S- 731 .?I ~ ~ j J / J S d i l . S I I &I I , .Voi.mrher, 1992.