On the geology of the southern part of the Macarena
DOI:
https://doi.org/10.32685/0120-1425/bolgeol6.1-3.1958.285Keywords:
Bauxite, layer, diamonds, cross stratification, Guayabero formation, plateausLicense
Copyright (c) 1958 Servicio Geológico Colombiano
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This work is licensed under a Creative Commons Attribution 4.0 International License.
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Abstract
The Sierra de La Macarena is located between latitudes 2° 10' and 3° 20' and longitudes 73° 40' and 74° 05' West of Greenwich. Sediments cover its southern part from the Recent to Upper Cretaceous age. Pebbles, conglomerates, and sandstones with cross-stratification, shales, and quartzite sandstones predominate with a general gentle dip to the East ranging between 3° and 4°. The presence of Siphogenerinoides clarki in the jasper pebbles confirms its Maastrichtian - Campanian age, as well as the finding of some pollen association in the shales of the Losada Formation, speak in favor of the Paleocene. Once the correlation of the La Macarena Formation with the Roraima Formation is proven, there is the possibility of finding economically exploitable diamonds in the pans and terraces of the rivers and streams that descend from La Macarena without violating its status as a national reserve.
An extensive area is covered by a pisolitic bauxite deposit up to 73% A12O3, veiled by a layer of iron oxide (limonite) about 0.6 m thick, with an iron content (Fe2O3) of 51.44%.
References
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