Toca da Boa Vista

Toca da Boa Vista (BA-082) is located within the municipality of Campo Formoso, 11 km east of the town of Lage dos Negros, in the State of Bahia, Brazil. It is part of the Chapada Diamantina mountain range. The area is karstified Salitre formation dolomite bedrock of the Una Group, the brazilian name of the Ediacaran, which is of Precambrian age, about 600 Ma old. This time at the end of the Precambrian was characterized by the beginning of multicellular life, and actually, the sedimentation of limestone was much different from the Mesozoic era. The microorganisms, which later reduced the amount of phosphates and sulfur in the loose sediment on the seabed before diagenesis started, did not yet exist. As a result, the chemistry of this dolomite is unique, and the high amount of phosphor and sulfur caused a unique process of cave formation. Groundwater set the sulfur free which was oxidized by microorganisms and created sulfuric acid, which again dissolved limestone. This process is called hypogene speleogenesis, where the acid which dissolves the limestone originates from the underground, the rock, instead of from the atmosphere.