Geological interpretation of eastern Cuba laterites from an airborne magnetic and radioactive isotope survey

Abstract

In eastern Cuba area several geophysical techniques have been applied to distinguish the main geological characteristics of the laterites which are of economical importance for the extraction of iron, nickel and chrome. The geophysical measurements include an aeromagnetic survey and thorium (eTh), potassium (K) and uranium (eU) isotope measurements. The results of gamma spectrometer measurements make a distinction between laterite reservoirs. The application of the magnetic and isotope methods allowed the determination of the distribution and development of the laterite crust, as well as the determination of hydrothermal alterations affecting the laterites, which is very useful for mining exploration and exploitation. Such alterations indicate the presence of silicates, which have negative effects on the metallurgic process. It is known that laterite crust has a high content of eU and eTh. From the content of the isotope abundance (eU and eTh) it was possible to infer that Moa laterites were formed before the Mayari Region. From the measurements it was also possible to infer the origin, thickness and age of the lateritic crust.