caa a22 4500 477063969 CHVBK 20180405111407.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00192074 doi (NATIONALLICENCE)springer-10.1007/BF00192074 Nd-Sr isotopic and trace element study of rocks and fluids from the continental deep drilling Project (KTB), Germany [Elektronische Daten] [F. Teichmann, A. Basu] Geochemical analyses were interpreted on the dominant lithological units and on a deep crustal fluid from the Continental Deep Drilling Project (KTB) Pilot Hole, situated at the western margin of the Variscan Bohemian Massif. The biotite gneiss (from 384 m depth) shows a rare earth element pattern very similar to the European shale composite with Nd model ages of 940 Ma (CHUR) and 1.4 Ga (DM). The lamprophyre dike in the upper profile (1549 m), a nepheline and olivine normative basalt, is geochemically and isotopically similar to rocks from the Tertiary Central European Volcanic Province. The lower metabasite sequence (3575-4000 m), with an intrusion age of approximately 500 Ma, is made up primarily of highly metamorphosed subalkalic olivine basalts. The geochemical characteristics of the metabasites are a (La/Yb)N of 5-10, an La concentration of 20-50 times chondrite as well as (87Sr/86Sr)i of 0.7035-0.7038 and ɛεNd(T) of 4-6. These values suggest a depleted mantle source for the igneous precursors, evolving by assimilation-fractional crystallization processes with up to 25% of upper crust into the ultramafic, basaltic, and intermediate rock types of the metabasite sequence. The strong geochemical and chronological similarities between the KTB metabasites and rocks from the Münchberg Massif suggest that these units belong to the same lithological complex. The high salinity as well as the radiogenic 87Sr/86Sr ratio of 0.709413 in the KTB fluid from 4000 m depth might be the result of migrating fluids reacting with the regional Permo-Mesozoic evaporite deposits, followed by extensive Sr isotopic exchange with the upper crust. Springer-Verlag, 1996 KTB pilot hole nationallicence Metabasites Geochemistry nationallicence Sr-Nd isotopes nationallicence Fluid Lamprophyre nationallicence Teichmann F. Department of Earth and Environmental Sciences, University of Rochester, 14627, Rochester, NY, USA aut Basu A. Department of Earth and Environmental Sciences, University of Rochester, 14627, Rochester, NY, USA aut Geologische Rundschau Springer-Verlag 85/1(1996-03-01), 162-171 0016-7835 85:1<162 1996 85 531 https://doi.org/10.1007/BF00192074 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00192074 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Teichmann F. Department of Earth and Environmental Sciences, University of Rochester, 14627, Rochester, NY, USA aut NATIONALLICENCE 700 1- Basu A. Department of Earth and Environmental Sciences, University of Rochester, 14627, Rochester, NY, USA aut NATIONALLICENCE 773 0- Geologische Rundschau Springer-Verlag 85/1(1996-03-01), 162-171 0016-7835 85:1<162 1996 85 531 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer