POTENTIAL DIAMONDIFEROUS STRUCTURES IN SOUTHWESTERN PART OF EAST-EUROPEAN-PLATE (EEP) - ROMANIA

Diamondiferous intrusions occurs on or near old cratonic areas (Groves D.I., Geology, 1987).

EEP, which include the Moldavian Plate and continues southward up to the North of Black Sea) has a subduction coupling with Carpathian Chain (part of the Alpine Plate), as deduced from magnetotelluric cross sections, gravity and magnetic data. In the same time, drillings made in Black Sea areas has met metamorphic rocks beneath the shelf, which are similar with those met in the British Isles and in Central England (Garetchi R.G., 1983). In the north-eastern part of Romania (on the EEP) at Ivancauti (on the Prut Valley) and Siretel (left side of Siret Valley), new minerals have been identified, among which there are to be mentioned diamond paragenetic minerals: violet pyrope, gahnite, moissanite, etc (Balan M., 1981). These two areas present geophysical anomalies similar with those of Brodicevsk (Ukraine), which are diamondiferous ones. Also, at Barlad, Ionici, Gusitei Valley, Oltenesti, Hoceni, Huica et al .( 1979) identified small grains which present fluorescence similar with that of diamond. At Barlad Valley, the identified garnets present a violet-reddish color (pyrope?). Important sites has been identified on both sides of Prut and Siret rivers (Semenenko, 1970). To note that all these structures are disposed eastward of the Teisseyre – Tornquist Zone (TTZ) lineament.

Pyrope identified in Northern Moldavia is identically with the Ukrainian one, which has a kimberlitic nature (Alexeeva V.P.et al.(1965), Smirnov G.I. et al.((970), Bobrievici et al. (1975).

Heavy minerals analysis made on gravel samples preleved from Ivancauti and Siretel Valley (1993), has leaded to a silicate composition similar with those found at Sao Paolo (Brazil) (Harris J., Nature, 1997).

South- west border of EEP in Romania is not “an eroded root of an archaic continent-continent collision”, as in Limpopo belt; on the contrary, it is too much overburden by other geological formations.