DBPapers
DOI: 10.5593/SGEM2014/B11/S5.057

COMPOSITION OF UPPERMOST CRUST BENEATH NORTHERN FENNOSCANDIA FROM INVERSION OF SEISMOLOGICAL DATA

I. Virshylo, E. Kozlovskaya, G.Prodaivoda, H. Silvennoinen
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-07-0 / ISSN 1314-2704, June 19-25, 2014, Book 1, Vol. 1, 427-434 pp

ABSTRACT
This work presents the result of velocity model inversion, which has been calculated from passive teleseismic LAPNET array data. The main aim of this investigation is to compute numerical model of dry uppermost mantle beneath Fennoscandia, which could explain known velocity model and has not disturbance with geological setting, mostly xenoliths composition and minerals equilibrium. Our calculations are based on multicomponent model with elastic minerals affected by pressure and heat flow. Elastic properties were calculated using method of conditional moments in isotropic approach. Heat flow affect was accounted by Gruneissen parameters formalism. Inversion procedure is realized by least-square method, which minimize misfit between calculated and previously inverted from traveltimes velocities. Understanding that inverted velocities obtained as a shift to 1D IASP model of bulk velocity, the initial model of mineral composition for such 1D distribution were calculate firstly. This model has not significant differences to garnet lherzolite composition in uppermost mantle (beneath Moho and above of 400 km depth level). Also another models such as eclogite has been checked.

Keywords:inversion, Fennoscandia, bulk velocity, shear velocity, uppermost mantle