CIMARRONA FORMATION, UPPER MESOZOIC IN CUNDINAMARCA, COLOMBIA

Cimarrona Formation is a set of coarse-grained sandstones to calcareous conglomerate; at the base, not compacted yellow sandstone, fine to medium grain over a homogeneous sequence of grey mudstone and strongly oxidized sandstone. There are a normal sequence of alternated fine grain sandstones, calcareous, compact, few thickness, and presence of small nodules. Over it the grain size is increased up to gravel (0.10 m.) with bands of oxidation. To the top calcareous lutites, limestone in strata up to 0.15 m. At the top a calcareous rock, coarse to conglomeratic grain with high fossil contain of approach 5,40 m. of thickness.

The main outcrops of Cimarrona Formation in the West of Cundinamarca described by Martinez & Vargas, 1978 along W flank of syncline named Guaduas-Dindal on La Paz-El Dindal road. Also, surrounding Los Monos andChorrillo Streams; in addition, at the low part of the high mountain named “Alto del Trigo.”

The stratigraphical place of Cimarrona Formation is over Plaeners member of the Olini Group and under the Tertiary Seca Formation.

The deposition of Cimarrona Formation indicated periods of deposition in calm and other periods of energy increment demonstrating gradual change of facies from marine to shadow platform as transition. The first geological note created by Washburne & White, 1922 and after, Porta J. De, 1965 re-defined it.

Miscellaneous fault from the North to the South in this area are representing the main tectonic and structural characteristics affecting the Cimarrona Formation putting Early Cretaceous in contact with Early Tertiary.

Finally, Cimarrona Formation looks a potential project for the oil industry with an acceptable oil trap conditions.