Hypogenic origin of Provalata Cave, Republic of Macedonia: a distinct case of successive thermal carbonic and sulfuric acid speleogenesis

Sulfur and oxygen isotopes in the gypsum deposits of the Provalata sulfuric acid cave (Macedonia)

“…The range of δ 34 S values is much wider than the previously reported values of -2.1 ‰ and -2.2 ‰ (Temovski et al, 2013). where it is more than three times larger.…”

“…Both phases are recognizable by distinct morphology and associated deposits, with phreatic morphologies covered by thick calcite coatings representative of the first phase, and vadose condensation-corrosion morphologies (feeders, half channels, pockets, cupolas), gypsum replacement crusts and other sulfate minerals (alunite, natroalunite, jarosite) formed as part of the second phase. Alunite and jarosite, which formed during the second phase, were Ar-Ar dated at ~1.5 Ma (Temovski et al, 2013). Preliminary sulfur isotope analysis from a sample of gypsum deposits gave values of -2.1 ‰ and -2.2 ‰ (Temovski et al, 2013).…”

“…Alunite and jarosite, which formed during the second phase, were Ar-Ar dated at ~1.5 Ma (Temovski et al, 2013). Preliminary sulfur isotope analysis from a sample of gypsum deposits gave values of -2.1 ‰ and -2.2 ‰ (Temovski et al, 2013). The cave is rich in gypsum deposits and, despite the old age of the SAS phase, they are quite well preserved, with intrusion of vadose waters notable only in a few locations where gypsum deposits have been mostly dissolved.…”

“…1). Provalata Cave has passages developed in marble during two geochemically different phases: the first due to cooling of CO 2 -rich thermal waters, and the second due to sulfuric acid dissolution, separated by filling of passages with clay deposits (Temovski et al, 2013). Both phases are recognizable by distinct morphology and associated deposits, with phreatic morphologies covered by thick calcite coatings representative of the first phase, and vadose condensation-corrosion morphologies (feeders, half channels, pockets, cupolas), gypsum replacement crusts and other sulfate minerals (alunite, natroalunite, jarosite) formed as part of the second phase.…”

“…The δ 34 S value of the sulfur in the speleogenetic gypsum depends on the pathways and processes which have occurred along the way, from the production of H 2 S, through oxidation to sulfuric acid, and deposition of gypsum. The original δ 34 S of the source H 2 S, if being A C C E P T E D M A N U S C R I P T above the water table (Temovski et al, 2013). As we cannot say much about the source of the H 2 S in the Provalata Cave, with nearby coal deposits considered as a possibility (Temovski et al, 2013), we will briefly review the processes and possible changes of the sulfur isotope values from when the H 2 S (aq) reached the cave, through its oxidation and sulfate deposition as gypsum.…”