Abstract

After describing the situation and access routes to the Páramo de Pisba region, general geology is studied physiologically, stratigraphically, and structurally. In the Socotá-Páramo de Pisba trajectory, two well-differentiated sets of sandstones can be distinguished. The first one can be seen from Socha towards the East along the road to the páramo; the second one appears in the páramo region itself. The first one is preliminarily assigned a Tertiary age (Guaduas and Bogota Formation) and the second one a Cretaceous age, correlated with the Cocuy sandstones.

The deposits of phosphate material occur in the localities of Motuba and El Tablón, in the paramo zone. In Motuba, there is a 3-meter-thick limestone bank with small alteration zones in the upper part where a brown phosphate material has been concentrated. The analysis of this material gave 9.06% of P205 and that of the limestone of the bank 0.40%. The amount of phosphate material is so small that it is of no interest in mining. In El Tablón, four phosphate strata were found, the richest had 12.69% P205 in the analysis. Because of its low phosphorus content and its small tonnage, the El Tablón deposit is also of no interest as a possible source of phosphates.