Wyniki wyszukiwania - BazTech

1

Anhydrite and gypsum in the Devonian and Permian evaporite lithofacies of Belarus : a review

Makhnach A., Shimanovich V., Streltsova G., Mikhajlov N.

Geological Quarterly

|

2014

|

Vol. 58, No. 3

577–590

EN

Anhydrite is widespread in the Prypiać Trough in the form of beds and nodules in the Subsaliferous Terrigenous and Carbonate formations (Eifelian and Frasnian), the Lower Saliferous Formation (Frasnian), the Intersaliferous and Upper Saliferous formations (Famennian). It is also present in the Asselian and Sakmarian (Lower Permian) deposits of the trough. The anhydrite is grey, blue, pink and orange. It has massive and, more rarely, horizontal bedding, and a fine- and micro-crystalline structure. Gypsum extends widely across the Orša Depression, Žlobin and Latvijas Saddles and partly in the Belarusian Anteclise, where it lies within the Eifelian deposits. It is also found in the Frasnian strata of the North-Prypiać Shoulder. As a component of facial analogue of the Upper Saliferous Formation gypsum forms the Bryniou deposit in the west of the Prypiać Trough. This mineral is also observed in the Oversaliferous Formation (Famennian) and in the Asselian and Sakmarian strata of the trough. There are spar, saccharoidal, alabastrine and selenitic varieties of gypsum. A medium to coarse crystalline structure is typical. The gypsum is grey, pink, yellow or orange.

2

Radiocarbon in elements of the landscape (Belarus)

Mikhajlov N., Kolkovskij V., Pavlova I., Luchina G.

Geochronometria

|

2004

|

Vol. 23

59-66

EN

It was found that in areas distant from an operating NPP the 14C concentration is characterized by values of 105-108 pMC. In the area of the Ignalina plant rather high 14C contents of vegetation (up to 150 pMC), and water of the lake Drisvyaty (127-154 pMC) connected by canals with the Ignalina NPP were noted. Biocarbonates (shells of lake mollusks Anadonta cygnaea and Dreissena, eggs poultry fed) are also enriched in radiocarbon. The concentrations of 14C in plants sampled in 1994-1996 in Gomel region (Chernobyl zone) are similar to those from the Ignalina NPP region and show increased values (up to 130-140 pMC). On the other hand, an emission of the radiocarbon resulted from the Chernobyl accident was recorded in the biosphere, at its concentrations increased toward the plant. So, 14C values were about 200 pMC near Minsk (May-June, 1986) and reached 600-700 pMC near Gomel. These data permit a realistic estimate of the concentrations of the radiocarbon emission at the instant of the accident. The radioisotope is well preserved and its redistribution occurs mainly due to biochemical processes. This is well shown by the radiocarbon distributions in a profile of the soil boggy medium.

3

Carbon isotopic composition of fresh groundwater in the territory of Belarus (in the context of its vulnerability estimation)

Mikhajlov N., Kolkovskij V., Pavlova I., Luchina G., Kolosov I.

Geochronometria

|

2004

|

Vol. 23

67-70

EN

Investigations of the distribution of the carbon isotopes (14C, 13C) at water intakes used for drinking water supply of Minsk (Quaternary and Upper Proterozoic aquifers complexes) and Gomel (Cretaceous and Paleogene aquifers) became the first stage of works aimed at the estimation of vulnerability of fresh groundwater aquifers in Belarus. The radiocarbon concentrations obtained and corrections for carbon stable isotopes were used to calculate the formal and corrected radiocarbon age (time of occurrence in an aquifer) of fresh groundwater of the studied aquifers. So, the most ancient radiocarbon age is characteristic of water samples from the Upper Proterozoic aquifer of Belarusian hydrogeological massif in the Minsk region (12,000-14,000 years). Fresh groundwater from the Cretaceous aquifer in the junction zone of the Pripyat artesian basin and Voronezh hydrogeological massif (Gomel region) show wider age range (7000-15,000 years). As aquifers of Belarus become younger, the groundwater isotope composition area comes more similar to the recent water area (II). An analysis of isotope ratios suggests (area I) that only a part of groundwater samples from Cenozoic aquifers (Paleogene and Quaternary Dnieper-Sozh horizon is found in the area of radioactive decay (this is more typical for water from Paleogene aquifer) and may corresponds to the actual time of its occurrence in an aquifer.

4

Sulphur isotopes in the basins with evaporites of chloride and sulphate types

Makhnach A., Mikhajlov N., Kolosov I., Gulis L., Shimanovich V., Demeneva O.

Biuletyn Państwowego Instytutu Geologicznego

|

1999

|

nr 387

47--48

5

Carbon, oxygen and sulphur isotopes as indicators of the evaporite process peculiarities

Makhnach A., Mikhajlov N., Kolosov I., Gulis L., Shimanovich V., Demeneva O.

Biuletyn Państwowego Instytutu Geologicznego

|

1999

|

nr 387

136--137