Cyrkon w utworach Zagłębia Żytawskiego .

Abstract

ZIRCON IN THE FORMATIONS OF THE ŻYTAWA BASIN Summary Analysis of heavy minerals found to occur in Tertiary and Quaternary formations of the Żytawa basin has demonstrated that :these formations are rich in zircon. The content of this mineral has been calculated in 4 fractions: 0.50 - 0.25 mm, 0.25 - 0.12 mm, 0.12 – 0.16 mm and 0.06 - 0.03 mm. Zircon is concentrated mainly in the fractions0.12 - 0.06 mm and 0.06 - 0.03 mm. Particularly strong concentration of this mineral has been found to occur in the Tertiary formations, in which the zircon content in two finer fractions frequently exceeds 90% by volume m the entire mass of heavy minerals (without; opaque minerals). In order to calculate the zircon content in the whole sample, without separating it into fractions, 5 analyses have been made. These demonstrate that the zircon content ranges here from 12.20 to 44.30% by volume. Both Rumburk and Zawidów granites are a source of zircon found In the Tertiary and Quaternary formations. Such a considerable concentration of zircon in the Tertiary formations is also a result of the elimination of other, less resistant minerals, mainly due to the weathering process and abrasion during water transportation.