Five sec tions from the Kielce Re gion of the Holy Cross Moun tains and one core from a bore hole drilled in the nearby west ern Me so zoic Mar gin re veal the best rec og nized de pos its from the De vo nian/Car bon if er ous bound ary in ter val. In four sec tions: Ruda Strawczyñska, Bolechowice IG 1, Zarêby IG 2 and Kowala, the De vo nian/Car bon if er ous bound ary is lo cated within a con tin u ous se ries of deep-wa ter car bon ates, whereas in the two re main ing: Ostrówka Quarry and the Jab³onna IG 1 borehole, the De vo nian/Car bon if er ous bound ary in ter val con tains strati graphic gaps re sult ing from lack of de po si tion in sub marine con di tions. The biostratigraphic po si tion of the analysed up per most De vo nian and low er most Car bon if er ous suc ces sion is de ter mined by as sem blages of cono donts, micro spores and deep-wa ter ostracodes of the Thuringian eco type. A dis tinctive suc ces sion of con tem po ra ne ous fauna as sem blages and lithofacies types is trace able from Holy Cross Mts. to Rhenish Mas sif. The main ex tinc tion oc curred dur ing a trans gres sion-pro moted an oxia, which then re verted in glacigenic re gres sion. The anoxic con di tions are well-ex pressed at Bolechowice and Kowala suc ces sions.

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Geological mapping and regional geochemical prospection on a scale of 1:50,000, covered an area of about 4,000 km 2 in the Zamtyn Nuruu region of the eastern Mongolian Altay. Northern part of the region is formed by the Lake Zone Terrane, the southern by the Gobi Altay Terrane; these two units are separated by the Bogd fault. The panned-concentrate heavy mineral survey was combined with the dry stream-sediment geochemistry, both being complemented by lithogeochemical sampling. The dry stream-sediment geochemistry proved to be a suitable method for regional prospection in semiarid to arid areas of Mongolia. The morphology and composition of placer gold grains were studied in order to estimate the distance from the primary source, and to constrain the nature of prospective primary mineral deposits. Based on the results of the regional geochemical survey and geological mapping, follow-up works were focused on prospective areas including the reconnaissance field works, detailed geochemical sampling, and geophysical measurements. New occurrences and signs of Au, Cu, Zn and (Ba)-As-Sb-Hg mineralizations were discovered. The ascertained goldbearing mineralizations are represented namely by Au and Au-(Ag) quartz veins in basic metavolcanic rocks of the Neoproterozoic Khan Taishir and volcanic rocks of the Permian Delger Khangay formations. Gold locally accompanies vein-disseminated base metal mineralization in some Proterozoic and Lower Palaeozoic formations. A prospective occurrence of clastic gold in Mesozoic conglomerates and sandstones was found at the northern edge of the Zamtyn Nuruu around the Samoandamba Uul. The geochemical survey has revealed a contrast in occurrence of ore indices between the two terranes formig the studied area. While the Lake Terrane and, especially, the Neoproterozoic Khan Taishir Formation are rich in gold and base metal showings, the Gobi Altay Terrane is barren.

Results of palynological studies of the Lower Devonian siliciclastic deposits of the Barcza Beds (Upper Pragian-Lower Emsian) from two abandoned quarries at Barcza in the Holy Cross Mts. is presented. Based on miospores, the biostratigraphic position of the tuffite horizon from the Barcza profile was defined as the early Emsian AB (annulatus-bellatulus) palynological Zone.

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