Genesis of paleokarst and strata-bound zinc-lead sulfide deposits in a Proterozoic dolostone, northern Baffin Island, Canada

Society Cliffs Formation; episodes of karstification since its deposition. During the first karst episode an evaporite solution-collapse breccia formed ubiquitously on the western Borden Peninsula. During the second karst episode a holokarst developed and an integrated cave system was formed. The caves subsequently were filled with sulfides and carbonate minerals; several interesting sedimentary structures exist in the zinc-lead sulfide deposits. The ore fluid and contained metals are postulated to have been derived during a late-stage dewatering of the black shale that underlies the Society Cliffs Formation. Sulfide deposition may have been caused by chemical reduction of sulfate that existed in the ore fluid when the fluid entered hydrocarbon-filled caves. During the third and fourth episodes of karstification, only merokarst developed in the Society Cliffs Formation. Karst effects which formed during these episodes include oxidized sulfide deposits and surface solution corridors.--Modified journal abstract.