Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Jaworska J.

Powiadomienia systemowe

Sesja wygasła!

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: Wapno Salt Dome

Sortuj według:

Ogranicz wyniki do:

An oxygen and sulfur isotopic study of gypsumfrom the Wapno Salt Dome cap-rock (Poland)

Jaworska J.

Geological Quarterly

2010

Vol. 54, No 1

25-32

The stable isotope compositions of oxygen and sulfur from gypsum samples derived from borehole cores of the Wapno Salt Domecap-rock have been determined. The d18O values were measured (for both the SO4 and the H2O) in bulk samples of gypsum(CaSO4 2H2O) and in its dehydrated equivalents (CaSO4). The SO4 is enriched in the heavy oxygen isotope, which unequivocally indicates the Zechstein sea as the place of origin of the sulfate. The variable δ18O values of the H2O (water of crystallization) indicate different conditions (and stages) of diagenetic processes of these samples, primarily recrystallization (hydration) episodes. Two groups ofgypsum were distinguished: (1) a group in which the δ18O values of H2O range between -9.0 and -10.2‰ (interpreted as gypsum in equilibrium with recent or subrecent meteoric water), (2) a group in which the d18O values of the H2O were less than -10.2‰ (this gypsum hasrecrystallized in the presence of water enriched in the light isotopes of oxygen). In addition, in one single analysis the δ18O value of the H>sub>2O amounts to -5.6‰ (gypsum with mixed isotopic composition).

Pochodzenie stylolitów w gipsach z czapy wysadu solnego Wapna

Jaworska J.

Przegląd Geologiczny

2006

Vol. 54, nr 2

166-169

Stylolites have been found in a core sample from the gypsum cap rock of the Wapno salt dome (figs 1-3) at a depth of 40 m below the land surface. These structures are inclined at 40-45ş to the core axis and cut by neomorphic gypsum crystals. Stylolites are products of the solution pressure. They commonly occur in carbonates but are very rarely encountered in evaporates, thus the origin and preservation of these structures in the cap rock of Wapno dome are interesting problems. Lithostatic pressure near the surface where the cap rock has been formed is insufficient to develop stylolites. Thus stylolites (fFigs 4-5) in gypsum cap rock of the Wapno salt diapir are probably early diagenetic structures preserved in a fragment of Zechstein anhydrite of Z2 or Z3 cyclothems. This anhydrite block with stylolites have been carried inside intruding salt masses to the top ofWapno dome. Halite and other easy soluble minerals had been dissolved, but the anhydrites with preserved stylolites have been incorporated in the cap rock and secondary altered into gypsum, similarly to the phenomenon found in Gorleben Salt Dome by Bäuerle et al. (2000).