. . . "4"^^ . "2890"^^ . . . . . "The goal of proposed study is to establish the petrogenetic evolution of the intraplate nephelinite to tephrite series (37-30 Ma), characteristic in high- and low-Ti contents and located in the riftogenic setting. The high-Ti rock types are characterized not only by distinctive high TiO2 contents (2.6-5.0 wt%), but also by Ti/Y ratios >500, similarly to basaltic (or tholeiitic) rocks in the LIPs. The low-Ti types exhibit <2.6 wt% TiO2 and Ti/Y ratio<500. Petrological and geochemical studies (electron microprobe, determination of trace elements using ICP-MS, INAA, PIGE and PIXE methods, Sr-Nd-Pb, oxygen stable isotopes, and K-Ar age determination) will be accomplished to constrain the comagmatic relations to one or several magmatic sources (degree of decompression melting, magmatic mixing/mingling and of lithospheric contamination). Rock magnetic properties and opaque mineralogy will contribute to interpretation of lava flows with both normal and reversal magnetic polarity."@en . . . "geochemistry; high-Ti and low-Ti basaltic rocks; xenoliths; trace elements; Sr-Nd-Pb isotopes; magnetic properties of rocks; Bohemian Massif; Oh\u0159e(Eger)rift"@en . "Geochemie, petrografie a magnetick\u00E9 vlastnosti alkalick\u00FDch bazaltoid\u016F bohat\u00FDch/chud\u00FDch titanem z vnitrodeskov\u00E9 riftogenn\u00ED pozice"@cs . "1"^^ . . . "2890"^^ . "2007-01-01+01:00"^^ . "2009-12-31+01:00"^^ . "3"^^ . "0"^^ . "4"^^ . . "Geochemistry, petrography and rock magnetic properties of the high- and low-Ti alkaline basalts from intra-plate riftogenic setting"@en . "C\u00EDlem je stanovit petrogenetick\u00E9 aspekty vzniku a krystalizace nefelinit\u016F a\u017E tefrit\u016F (37-30 mil. let) s vysok\u00FDmi a n\u00EDzk\u00FDmi obsahy Ti, je\u017E se vyskytuj\u00ED v intradeskov\u00E9 riftogenn\u00ED pozici. Tyto alkalick\u00E9 bazaltoidy jsou charakterizov\u00E1ny obsahy TiO2 v rozsahu 2,6- 5,6 hm. %), a pom\u011Brem Ti/Y >500 a podobaj\u00ED se plateau bazalt\u016Fm z velk\u00FDch vulkanick\u00FDch provinci\u00ED. Z\u00E1m\u011Brem studie bude vy\u0159e\u0161it tak\u00E9 problematiku vzniku typ\u016F chud\u00FDch titanem (<2,6 % TiO2) a s pom\u011Brem Ti/Y <500. Proto bude vyu\u017Eito z\u00E1kladn\u00ED petrografick\u00E9 a geochemick\u00E9 studium (elektronov\u00E1 mikrosonda, stanoven\u00ED stopov\u00FDch prvk\u016F pomoc\u00ED ICP-MS a INAA, stanoven\u00ED st\u00E1\u0159\u00ED K-Ar metodou, vyu\u017Eit\u00ED izotopick\u00FDch pom\u011Br\u016F Sr,Nd a Pb, v\u010Detn\u011B studia magnetick\u00FDch vlastnost\u00ED hornin). Bude testov\u00E1na komagmati\u010Dnost k jednomu nebo n\u011Bkolika magmatick\u00FDm zdroj\u016Fm, odli\u0161nost krystaliza\u010Dn\u00EDho v\u00FDvoje (stupe\u0148 dekompresn\u00EDho taven\u00ED, magmatick\u00E9 m\u00ED\u0161en\u00ED, kontaminace litosf\u00E9rou)."@cs .