Objective The oxygen isotopic composition of minerals is sensitive indicators for conditions of their formation. Until now, stable isotope studies largely have been focused on rock-forming minerals. Far less attention has been paid to accessory phases which are difficult to obtain in analytical amounts and which in many cases are difficult to decompose for isotopic analysis.Many rock - forming minerals can hardly preserve oxygen isotope ratios acquired during their formation due to later exchange processes. Preliminary results on some accessory phases (e.g. zircon) show very low mobility of oxygen and hence the potential of accessory phases to "look through" secondary processes in order to evaluate the conditions of primary processes, especially in high-grade terrains. Moreover, rock-forming minerals usually give little temporal constraints. Accessory minerals, however, frequently are the carriers of radiogenic isotopes and thus can be used to obtain age information. Therefore, an attempt to utilize different (radiogenic and stable) isotopic systems in one and the same accessory mineral could serve as a most promising tool to relate geochronological "events" with geological and petrological data.The aim of this project is to work out the base for use of accessory phases in stable isotope geochemistry. The main objectives of the planned study include(i) obtaining new data on oxygen isotopic fractionations between accessory phases and rock-forming minerals in rocks of different origin;(ii) development of new calibrations of oxygen isotopic geothermometers including accessory phases;(iii) determinations of oxygen mobility in accessory phases in relation to geological processes in comparison with mobility of elements used for dating (U-Pb, Sm-Nd, Rb-Sr).An attempt will be also made to reconstruct thermal and fluid evolution of high-grade metamorphic and ultrametamorphic Precambrian rocks (case studies from the Svecofennian Shield, South-West Greenland, East Antarctica, and the Ukrainian Shield) using oxygen isotopic distribution between accessory phases and other minerals in combination with petrological, geochronological and geochemical data. The planned studies should thus provide new insight into the origin and the time - temperature - fluid history of rocks in high-grade terrains, which in turn represent the key for the understanding of the geodynamic processes in the Earth crust. Programme(s) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Topic(s) 5 - Earth Sciences, Environment, Energy INTAS - INTAS Call for proposal Data not available Funding Scheme Data not available Coordinator Universitat Bonn EU contribution No data Address Poppelsdorfer Schloss 53115 Bonn Germany See on map Total cost No data Participants (4) Sort alphabetically Sort by EU Contribution Expand all Collapse all Copenhagen University Denmark EU contribution No data Address Oster Voldgade 5-7 1350 Copenhagen K See on map Total cost No data Institute of Precambrian Geology and Geochronology Russia EU contribution No data Address Makarova Nab., 2 199034 St. Petersburg See on map Total cost No data National Academy of Sciences of Ukraine Ukraine EU contribution No data Address Palladina Ave., 34 03142 Kiev See on map Total cost No data University of Lund Sweden EU contribution No data Address Solvegatan 13 223 62 Lund See on map Total cost No data