Littoral dripstone and flowstone--non-spelean carbonate secondary deposits

Abstract

Speleothem-like dripstone and flowstone deposits can form in the non-spelean environments of marine notches on tropical carbonate coastlines. Hereby termed "littoral dripstone" and "littoral flowstone" to distinguish them from genuine cave deposits, they reflect the basic speleothem types: draperies, stalactites, stalagmites, and columns. Nevertheless, these formations lack the luster and crystallinity of cave analogues, and are not nearly as well-developed, dense, and massive. They are composed of layered microcrystalline aragonite and calcite, are generally highly porous, and invariably overlie dissolutional and bioerosional karren. Because true speleothems, often found in the remnants of solution voids breached by coastal erosion, are also commonly present in the modern littoral environments on tropical carbonate islands, they could be confused with littoral dripstone and flowstone deposits. The distinction between the two is crucial, because the true speleothems are indicators of karst cave paleoenvironments, while littoral dripstone and flowstone are contemporary parts of the modern coastal landscape.

Speleothems in a wave-cut notch, Cayman Brac, British West Indies: The integrated product of subaerial precipitation, dissolution, and microbes

“…2), on sea cliffs (Taboroši et al, 2006), and in wave-cut notches (Antonioli et al, 2002;Taboroši and Stafford, 2003). In order to separate them from cave speleothems, those found on sea cliffs and in wave-cut notches have been referred to as "non-vertical stalactites" and "stalactite tufa" (Bull and Laverty, 1982), "tufa-like speleothems" (Ford, 1989), "gigantic stromatolite stalactites" (Forti, 2001), "outside stalactites" (Sweeting, 1978;Taboroši and Hirakawa, 2004), "remora" (Pentecost, 1993), "littoral dripstones" and "littoral flowstones" (Taboroši and Stafford, 2003), or "exposed stalactites and stalactitic tufa" (Taboroši et al, 2006). Herein the prefix "notch" is used to distinguish them from similar structures that form on cliff faces and in caves.…”