Abismo de Simão Dias (Furna do Dorinha, SE-08)

Known in Simão Dias, in inland Sergipe, as Furna do Dorinha, this cavity is listed in the National Cave Registry under the name Abismo de Simão Dias (SE-08). In the 1990s, the now-defunct Centro Espeleológico de Alagoas, a pioneering group in Sergipe caving, carried out explorations and dives in the shaft.

Inside, a huge speleothem curtain drops from the highest part of the shaft to near the water level. The inner lake is 14.20 m long and 9.90 m wide. Its water has a high salt concentration, which makes it dense, and is supersaturated with calcium carbonate, because the cave is formed mainly of carbonate rocks.

On 13 and 14 December 2016, a mission with the Sergipe Public Prosecutor's Office, the Fire Department and the Federal University of Sergipe set up a floating platform and dived in the lake, confirming the existence of submerged conduits. During that dive, tyres, PVC pipes, logs and branches were found in the lake, and a motorcycle fuel tank still holding fuel, which never leaked, was removed from the water. A fossilised tortoise shell of the genus Geochelone was also found in the shaft, and judging by its degree of fossilisation the animal would have lived in the late Pleistocene or early Holocene. The specimen is kept at the Paleontology laboratory of the Federal University of Sergipe.