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A flight of marine terraces along the Cuban coast records Quaternary sea-level highstands and a general slowly uplifting trend during the Pleistocene. U/Th dating of these limestone terraces is difficult because fossil reef corals have been affected by open system conditions. Terrace ages are thus often based on geological and geomorphological observations. In contrast, the minimum age of the terraces can be constrained by dating speleothems from coastal mixing (flank margin) caves formed during past sea-level highstands and carving the marine limestones. Speleothems in Santa Catalina Cave have ages >360ka and show various cycles of subaerial-subaqueous corrosion and speleothem growth. This suggests that the cave was carved during the MIS 11 sea-level highstand or earlier. Some stalagmites grew during MIS 11 through MIS 8 and were submerged twice, once at the end of MIS 11 and then during MIS 9. Phreatic overgrowths (POS) covering the speleothems suggest anchialine conditions in the cave during MIS 5e. Their altitude at 16m above present sea level indicates a late Pleistocene uplift rate of

Unusual speleothems resembling giant mushrooms occur in Santa Catalina Cave, Cuba. Although these mineral buildups are considered a natural heritage, their composition and formation mechanism remain poorly understood. Here we characterize their morphology and mineralogy and present a model for their genesis. We propose that the mushrooms, which are mainly comprised of calcite and aragonite, formed during four different phases within an evolving cave environment. The stipe of the mushroom is an assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts that were subsequently encrusted by cave clouds (mammilaries). More peculiar is the cap of the mushroom, which is morphologically similar to cerebroid stromatolites and thrombolites of microbial origin occurring in marine environments. Scanning electron microscopy investigations of this last unit revealed the presence of fossilized extracellular polymeric substances (EPS) – the constituents of biofilms microbial mats. These organic microstructures are partially mineralized with Ca-carbonate, suggesting that the mushroom cap formed through a microbially-influenced mineralization process. The existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence of phototrophs) has interesting implications for the study of fossil microbialites preserved in ancient rocks, which are today considered as one of the earliest evidence for life on Earth.

Durante la spedizione organizzata da La Salle 3D – International Team, Photo, Video and Documentation nel Dicembre 2012 sono state studiate diverse grotte nei pressi di Matanzas, sulla costa settentrionale dell’Isola di Cuba a circa 90 km ad E dell’Avana. In particolare nella Cueva de Santa Catalina è presente una ricchissima associazione di speleotemi tra cui le comuni stalagmiti, stalattiti, colonne, vaschette, colate e perle di grotta, di recente formazione nelle attuali condizioni vadose, ma anche forme più rare come cave clouds, coni, calcite flottante, folia e “funghi” formatisi in tempi passati quando la grotta era parzialmente allagata. Sono le ultime ad aver reso famosa la grotta in tutto il mondo. In questo lavoro vengono illustrate le caratteristiche mineropetrografiche di questi rari speleotemi, che insieme alla morfologia degli stessi, portano ad ipotizzare l’ambiente molto particolare in cui si sono formate.

Unusual speleothems resembling giant mushrooms occur in Cueva Grande de Santa Catalina, Cuba. Although these mineral buildups are considered a natural heritage, their composition and formation mechanism remain poorly understood. Here we characterize their morphology and mineralogy and present a model for their genesis. We propose that the mushrooms, which are mainly comprised of calcite and aragonite, formed during four different phases within an evolving cave environment. The stipe of the mushroom is an assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts that were subsequently encrusted by cave clouds (mammillaries). More peculiar is the cap of the mushroom, which is morphologically similar to cerebroid stromatolites and thrombolites of microbial origin occurring in marine environments. Scanning electron microscopy (SEM) investigations of this last unit revealed the presence of fossilized extracellular polymeric substances (EPS)—the constituents of biofilms and microbial mats. These organic microstructures are mineralized with Ca-carbonate, suggesting that the mushroom cap formed through a microbially-influenced mineralization process. The existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence of phototrophs) has interesting implications for the study of fossil microbialites preserved in ancient rocks, which are today considered as one of the earliest evidence for life on Earth., Frontiers in Earth Science, 4, ISSN:2296-6463