Estudo da distribuição dos minerais pesados existentes nos bancos de areia do Estuário dos Bons Sinais

Abstract

The present work was carried out in the sandbanks present along the Bons Sinais estuary, whose objective was to know the heavy minerals existing in the sediments of the same. Thirty (30) sediment samples were collected, in which seven heavy minerals were identified, among them the light heavy ones such as quartz, albite and muscovite which can also be considered heavy heavy, and the heavy heavy minerals enstatite, titanite , topaz and columbite and the latter two are considered gem or precious stone. Quartz and albite are distributed in all banks, this may be associated with their crystallography, density, stability and resistance to weathering, and the remaining minerals due to their density, some because they are associated with immature sediments and because they are rare for a long time. so that they are not distributed in all the banks that exist along the estuary of good signs. Quartz was the mineral that presented the highest percentage of 54.2%, although albite was surpassed in other points, such as in the port bank and in the chuabo dembe bank, which had a percentage of 50%, the enstatite that was only identified in the bank from the port with 26.4%, this may be associated with the type of clayey sediment that composes it, muscovite with 21.9%, titanite with 18.5%, topaz with 10.2% and finally columbite with only 1.2%. The percentages vary from each sampling point and reference that heavy minerals occur in fine fractions. And with regard to the speed of the tidal currents, a value of 0.16 m/s was obtained at the ebb of the spring tide, where more sediment transport occurs, which can somehow contribute to the distribution of heavy minerals in the estuary.