The structure and composition of the upper mantle strongly influence magma generation processes initiated by plumes or subduction. Interactions of melts and fluids from plumes with mantle roots in different environments change both compositions and structure of the asthenosphere and lithosphere and transform the melts. Xenoliths extracted by magmas on their way to the surface and allow us to reconstruct the polybaric conduits, chamber systems and wall rocks. We welcome talks presenting the results of investigations devoted to
1) reconstruction of the structures and compositions of the mantle roots based on PT estimates and detailed geochemistry of mantle and lower crustal xenoliths in of deep seated magmas such as alkali basalts and kimberlites;
2) reconstruction the conditions and substrate of primary and contaminated mantle magmas using whole rock geochemistry as well as trace-element and isotope geochemistry of xenocrysts and phenocrysts;
3) discussion of the nature and development of metasomatic agents;
4) models for the origin of the stratification of asthenospheric roots reconstructed from petrological and geophysical data and their influence on the evolution of mantle melts;
5) links between high P-T experiments under mantle conditions and data obtained from the petrology of natural xenoliths and magmas;
6) models of rising mantle melts, xenoliths and xenocrysts including diamonds based on theoretical and petrological data;
7) thermodynamic and mathematic modeling of heterophase interaction at the top of mantle plumes;
8) oxygen fugacity of mantle rocks: fluctuation and mechanisms;
9) vertical motions of the melts and solids including ascent of mantle diapirs;
10) mantle roots of the large igneous provinces