Objectif This research project will study a new phenomenon discovered by Russian scientists: the unprecedented enrichment of 3He (up to 10-7 cc/g) in microdiamonds from metamorphic rocks of the Kokchetav massif (northern Kazakhstan) so that the 3He/4He ratio exceeds that in the solar wind by a factor of 1,000 and is equal to 0.7.The research activities to be carried out concern He isotope analysis; isotope investigations of other noble gases and elements; investigation of Li and U distribution in the diamond containing rocks; and geological and mineralogical investigations. Scientists from the Central Research Institute of Geological Prospecting for Base and Precious Metals of the Russian Geological Committee (Moscow) and the Kokchetav Geological Survey (Kokchetav) will provide samples of the microdiamonds and their host rocks and carry out mineralogical and petrographic investigations. In the Vernadsky Institute of Geochemistry and Analytical Chemistry (Moscow), the Open University (Milton Keynes) and the Max-Planck-Institut für Chemie (Mainz) will perform a complex investigation of isotopic composition of He, Ne, Ar, Xe, C, N and H in the microdiamonds and their host rocks. The Max-Planck-lnstitut für Kernphysik (Heidelberg) will search for peculiarities in the chemical compositions of the bulk samples and explore the distribution of Li and U by means of radiography in conjunction with the Vernadsky Institute.The overall aim of these investigations is to find an explanation for enormous excess of 3He in microdiamonds and to provide information on the occurrence and origin of microdiamonds in metamorphic rocks.The expected result is to obtain an acceptable explanation for the diamond formation in the metamorphic rocks and for the nature of the 3He excess in the microdiamonds such as to locate precisely the excess 3He in the samples by identifying correlation with another element. The work will be published in leading international journals and reported at appropriate conferences. Programme(s) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Thème(s) 52 - Geochemistry Appel à propositions Data not available Régime de financement Data not available Coordinateur Open University Contribution de l’UE Aucune donnée Adresse Walton Hall MK7 6AA Milton Keynes Royaume-Uni Voir sur la carte Coût total Aucune donnée Participants (3) Trier par ordre alphabétique Trier par contribution de l’UE Tout développer Tout réduire Central Research Institute of Geological Prospecting for Base and Precious Metals Russie Contribution de l’UE Aucune donnée Adresse 113545 Moscow Voir sur la carte Coût total Aucune donnée Russian Academy of Sciences Russie Contribution de l’UE Aucune donnée Adresse 117975 Moscow Voir sur la carte Coût total Aucune donnée State Holding Company Marjan Kazakhstan Contribution de l’UE Aucune donnée Adresse 475015 Kokchetav Voir sur la carte Coût total Aucune donnée
