The age curves of sulfur and oxygen isotopes in marine sulfate and their mutual interpretation

Barite, BIFs and bugs: evidence for the evolution of the Earth’s early hydrosphere

“…In contrast, deposits younger than 2.4 Ga have higher and more variable N 34 S sulfate , ranging from 4 to 39x (Fig. 1), similar to values in the late Proterozoic and Phanerozoic [18]. Sedimentary sul¢des also have a large range in N 34 S, from 330 to 60x [13,19,20].…”

Oxygen and sulphur isotopes of gypsum from the Mogilno Salt Dome cap-rock (Central Poland)

“…The frac tion ation dis tin guishing dis solved cal cium sulphates in oce anic wa ter from gyp sum or anhydrite is neg li gi ble (Thode and Mon ster, 1965;Raab and Spiro, 1991), so that re cently de pos ited sulphates in ma rine evaporite bas ins have the same d 34 S value as the sea wa ter (Claypool et al, 1980). The d 34 S val ues for cal cium sulphates in the geo log i cal past have changed, but the gen eral trends (S-iso tope age curve), in clud ing mi nor os cil la tions (Niel sen, Oxygen and sulphur isotopes of gypsum from the Mogilno Salt Dome cap-rock (Central Poland) 255 1989), are well-known (see Claypool et al, 1980;Holser et al, 1989;Strauss, 1999Strauss, , 2004. Zechstein evaporites are char ac ter ized by min i mum d 34 S val ues for the Phanerozoic (close to 10-12‰; see Garcia-Veigas et al, 2011).…”

“…The 18 O/ 16 O ra tio in evaporites has changed slightly over geo log i cal time and the gen eral trend is known. The re sul tant O-iso tope age curve can be used to de ter mine the time of evaporite pre cip i ta tion, and Zechstein evaporites show, like the d 34 S val ues, a min i mum d 18 O value for the Phanerozoic, close to 10‰ (see Claypool et al, 1980). This is con sis tent with the ox y gen-iso tope data for Zechstein evaporites from north east ern Po land (polyhalite) (10.0-13.5‰; Peryt et al, 2005), south west ern Po land (9.4-10.4‰; Vovnyuk and Czapowski, 2007) and West Poland (9.4-15.5‰ in anhydrite;Peryt et al, 2010).…”

Mineralogy, geochemistry and sulfur isotope characterization of Cerro de Maimón (Dominican Republic), San Fernando and Antonio (Cuba) lower Cretaceous VMS deposits: Formation during subduction initiation of the proto-Caribbean lithosphere within a fore-arc

“…high as 7.0 ‰; all the δ 34 S values are consistently lower than that of the starting seawater sulfate, of ~15 ‰ during the Cretaceous (Claypool et al, 1980). Sulfides from Cerro de Maimón returned lower values and more reduced scatter of δ 34 S than those analyzed from the San Fernando and Antonio deposits.…”