Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 76. (Budapest 1984)

Embey-Isztin, A.: Texture types and their relative frequencies in ultramafic and mafic xenoliths from Hungarian alkali basaltic rocks

Textural properties of spinel lherzolite and harzburgite xenoliths As we have seen, this group of xenoliths are available in great quantities for the purposes of the statistical investigation only at four localities in Hungary (Fig. 1). At three of these localities the host rock is basaltic tuff (Szentbékálla, Szigliget, Gérce), while in the case of Bondoró-hegy it is a basanite. The chemistry of these inclusions is very similar to those described from other parts of the world (e. g. Ross et al. 1954; WHITE, 1966; KUTOLIN & FROLOVA 1970; CARTER 1970 and many others). Thus the mg-number of nodular olivines varies between 89.30 and 92.07, that of the orthopyroxenes being slightly higher (EMBEY-ISZTIN 1978). In the following, textural properties of the inclusions originating from the four localities will be separately discussed. Fig. 1. Map of the young alkali basaltic region of Transdanubia : 1 = basaltic tuff, 2 ^basaltic lava flow. 3 = thrust fault