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ABSTRACT. The paper presents a comparison of U-series and radiocarbon dates of speleothems collected in several caves in central and southern Europe and southeast Africa. Despite a large spread of dates, mainly due to contamination with younger carbon, the group of corresponding 14 C and 230 Th/U ages of speleothem samples seems to be coherent with the previous suggestion of large deviation between the 14 C and the absolute time scale between 35 and 45 ka BP. This agrees with the result of frequency analysis of published 14 C and 230 Th/U ages of speleothem.

Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. China, and is then applied to an undated stalagmite from southern Poland. 46The new method will not replace high-precision U-Th measurements, 47 because the precision of the technique is difficult to quantify. However, it 48 provides a means for dating certain stalagmites undateable by 49 conventional U-Th methods and for refining coarse U-Th chronologies. 50 51

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Pruner: Podrobna magnetostratigrafska analiza sige iz Sneaene jame, Kamniπko-Savinjske alpe, Slovenija Sneaena jama je velika vodoravna fosilna epifreatiËna jama. Leaei v grebenu Raduhe, V delu Kamniπko-Savinjskih Alp v SV Sloveniji. V bliaeini vhoda je v jami v okrog 3 m visok prerezu razgaljeno zaporedje plasti sig s πtevilnimi prekinitvami rasti in izdatno terigeno komponento v spodnjem delu. V 2,4 m dolgem zveznem profilu smo vzeli zaporedne vzorce , ki smo jih prouËili z termalno demagnetizacijsko metodo in metodo spreminjajoËega magnetnega polja. Magnetostratigrafske analize so pokazale 7 normalnih in 6 reverznih magnetocon. Magnetne lastnosti se dobro ujemajo z litoloπko mejo v profilu sige. Spodnji del profila kaaee veËjo magnetno susceptibilnost in moËnejπo remanentno magnetizacijo. Sprememba lastnosti v profilu nakazuje pomembno paleogeografsko spremembo v Ëasu nastajanja sige. Starost sige sega izven dosega datacijske metode alfa spektrometriËne analize U razpadne vrste; ravnoteaeje U izotopov pa nakazuje starost veËjo od 1,2 Ma. Najbolj verjetna starost sige, ki jo dobimo z korelacijo s primerjavo z geomagnetno Ëasovno skalo je bodisi 3,0 do 5,0 ali 1.8 do 3.6 Ma. Starost jame lahko primerjamo z nekaterimi brezstropimi jamami na krasu v JZ Sloveniji, kjer sedimentacijo v jamah postavljamo v mesinsko obdobje. Sneaena jama je bila dvignjena v sedanjo viπino z mlajπimi (plio-pleistocenskimi) dvigovanji Alpskega loka.

Caves are important markers of surface evolution, since they are, as a general rule, linked with ancient valley bottoms by their springs. However, caves can only be dated indirectly by means of the sediments they contain. If the sediment is older than common dating methods, one has to use multiple dating approaches in order to get meaningful results. U/Th dating, palaeomagnetic analysis of flowstone and sediment profiles, cosmogenic dating of quartz pebbles, and mammalian dating allowed a robust estimate of speleogenesis, sediment deposition, climatic change at the surface, and uplift history on the Periadriatic fault line during the Plio-Pleistocene. Our dates indicate that Snežna jama was formed in the (Upper) Miocene, received its sedimentary deposits during the Pliocene in a rather low-lying, hilly landscape, and became inactive due to uplift along the Periadriatic and Sava faults and climatic changes at the beginning of the Quaternary. Although it is only a single cave, the information contained within it makes it an important site of the Southern Alps.