The Baja Verpaz Ophiolitic Belt in Guatemala
Description
The Baja Verapaz ophiolite complex (BVP) is one of the six ophiolites in Guatemala associated with the Motagua Suture Zone (MSZ). The MSZ represents the NW corner of the Caribbean Plate with ages of obduction ranging from post Triassic to Tertiary in a west - east direction. The geological information of BVP presented in this publication is the result of the mapping efforts of the team of Nichromet Guatemala, S.A. directed by Ricardo Valls, P. Geo., together with the interpretation of the aeromagnetic survey recently completed by the Company with the financial support of CVRD. This includes a model of the geological evolution of the complex as well as an updated stratigraphic column for Central Guatemala. Nickel-cobalt laterites are the most important ore resource in this area. A typical laterite profile consists of 10 to 12 meters of a "Limonitic Horizon", followed by a leached zone called the "Mottled Zone", with thickness from 0 to 2 meters. The Mottled Zone contains the "Stoneline" and is usually enriched in heavy metals like gold, chromite, and platinum group metals. The "Saprolite Horizon" is located below the Mottled Zone and ranges from 15 to 20 m thick. It overlies the "Saprock" with thickness of one to two meters. The "Saprock" grades transitionally into the unaltered bedrock. Full lateritic profiles develop only over serpentinized olivine-rich rocks. Because of their young age, Guatemalan laterites still contain large amounts of magnetite. Aeromagnetic surveys are therefore effective not only as a mapping tool, but also to locate new lateritic targets. Satellite image interpretation is another technique used for the location of laterites. Finally, the Company recently completed a lineament analysis that merged all this information and defined several new lateritic targets within the ophiolitic complex.