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Equilibration technique suitable for a large amount of samples is described for hydrogen and oxygen isotope analyses of ground ice, especially ice wedges, including the sampling strategy and the analytical procedure as well as the calibration of the Finnigan MAT Delta-S mass spectrometer in June, 1999. Since for future analyses of ice wedges, a higher sampling resolution with limited sample volume is required, the limit of the equilibration technique for small water sample sizes of between 0.05 and 5 ml was checked. For water samples smaller than 1 ml, corresponding to a molar ratio [H2O]/[H2] of smaller than 0.994, a balance correction has to be applied. The experimental errors due to partial evaporation during evacuation, the balance calculation of the isotope equilibration process, the linearity as well as memory effects of the mass spectrometer for samples with large differences in delta18O and deltaD are tackled in this paper. In the polar regions of Northern Siberia without Late Pleistocene and Holocene glaciation, ground ice is used as an archive for paleoclimate studies. First results of stable isotope measurements on ice wedges clearly show a shift towards heavier isotopes and thus warmer winter temperatures as well as a change in the source of the precipitation between Late Pleistocene and Holocene. These results indicate the high potential of ground ice for paleoclimate studies.

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Das Menderes Massiv ist ein alpinotypes Gebirge derWest-Tfirkei und besteht aus drei tektonisch-lithologischen Einheiten, die in den ,,Gneisskern, und in die ,,Schieferhfille,~ und ,,Marmorhfille,~ gegliedert werden. Diese Arbeit berichtet fiber Isotopenanalysen, die an einer metasediment/iren und migmatitischen Gesteinsserie yore Sfidrand (Typ A) und an einer metatonalitischen bis metagranitischen Gesteinsserie yore Nor&and des Menderes Massivs (Typ B) durchgefiihrt wurden.Die Rb-Sr-Gesamtgesteinsisochrone der Gesteine (Typ A) definiert ein Alter yon 502 + 10 Ma und ein initiales S7Sr/S6Sr-Isotopenverh~.lmis yon 0.71174 _+ 73. Dieser AIterswert wurde als Zeitraum der Migmatisierung interpretiert. Die Rb-Sr-Gesamtgesteinsisochrone der Gesteine (Typ B) ergibt ein Alter yon 471 __ 9 Mabei einem initialen 87Sr/86Sr-Isotopenverh~ilmis yon 0.70684 +_ 25, wobei dieser Alterswert als Intrusionsalter gedeutet wird.Der Zeitraum der Kristallisation alpiner Mineralparagenesen wird dutch einen mittleren Rb-Sr-Hellglimmeralterswert yon 56 _ 1 Ma erfa~t. Die Hellglimmer aus dem Gesteinstyp B ergeben Rb-Sr-Mischalter yon 120-230 Ma, die im Zeitraum zwischen der mittelalpinen und der kaledonischen Metamorphose liegen. Die Biotite aus den beiden Gesteinstypen (A und B) definieren einen mittleren Rb-Sr-Alterswert yon 37 4-1 Ma, der als das alpine Abkiihlalter interpretiert wird.Die AbstractThe Menderes Massif, located in the Alpine orogen of Western Turkey, has three litho-structural units, a basal ,,gneiss core% a ,,schist mantle,~ covering the gneiss core, and an overlying ,,marble mantle~,. This study reports isotopic data from samples of rnetasediments and migmatites from the southern (Type A) and of tonalitic to granitic metaigneous rocks from the northern Menderes Massif (Type B).Type A rocks define a Rb/Sr whole rock isochron age of 502 q-10 Ma and an initial STSr/S6Sr ratio of 0.71174 _+ 73. This is interpreted as the age of migmatization. Type B rocks give a Rb/Sr whole rock isochron age of 471 _+ 9 Ma with an initial SVSr/S6Sr ratio of 0.70684 + 25, which we interpret as the intrusion age.K-White micas from rock type A give an average Rb/Sr mineral age of 56 +_ 1 Ma, which can be interpreted as the formation age of the Alpine mineral paragenesis. K-white micas from rock type B give Rb/Sr mixed ages of 120-230 Ma between Alpine and Pan-African orogenies. Biotites from both rock types yield an average Rb/Sr age of 37 4-1 Ma, which is interpreted as an Alpine cooling age.The oxygen isotope ratios of type A rocks range from 10.4 to 14.6%o, and of type B from 8.9 to 11.8%o. The oxygen and strontium isotopic compositions together clearly distinguish rocks of types A and B. Compositions of type A rocks suggest a crustal origin: type B rocks have compositions transitional between those of crustal and mantle-derived materials.