GEOLOGY, GEOCHEMISTRY AND AGE OF A CU-MO-BEARING GRANITE AT KABELIAI,SOUTHERN LITHUANIA

A Cu-Mo-bearing granitoid belonging to the concealed Precambrian cryst alline basement of Lithuania has been dated by the U-Pb zircon method and investigated geochemically. The granitoid is located at Kabeliai i n southernmost Lithuania and forms part of a granitoid complex recogni zed as the Marcinkonys batholith. The Kabeliai granite is composed of quartz, plagioclase, microcline and biotite and shows a granitic to ad amellitic peraluminous/metaluminous composition with dominantly 1-type chemistry. U-Pb dating of zircon yields an age of 1505 +/- 11 Ma, whi ch is considered to reflect the crystallization age of the granite. Th e Kabeliai granite displays several similarities in terms of geologica l setting, chemistry and age with certain granitoids in northeastern P oland (Mazury complex) and northwestern Belorussia (Mostovsky, Kamensk y and Vydgodsky plutons), which are considered ''rapakivi-like'' in th e literature. It is, however, uncertain whether proper rapakivi granit es really exist in these areas as none of these granitoids displays th e common characteristics of rapakivi granites (A-type chemistry, wibor gitic textures, associated Sn-Be-Pb-Zn-Cu mineralizations). We specula te that the 1.4-1.5 Ga granites southeast of the Baltic Sea rather mig ht be correlated with granites of comparable age and geochemical chara cter in southwestern Sweden. Another possible alternative is that the granitoids in Lithuania may not be correlated with any part of the Fen noscandian Shield.