LITHOGENIC NATURE OF GOLD-BEARING MINERALIZATION IN PRE-CAMBRIAN PSEPHITES OF THE ROSTOV LEDGE, UKRAINIAN SHIELD
DOI: 10.24411/0869-5997-2019-10031
Keywords:
Rostov ledge, gold mineralization, Pre-Cambrian, conglomerates, sandstones, potassium geochemistry, epigenetic albitization.Abstract
The paper reviews the nature of gold mineralization in the upper Proterozoic conglomerates and sandstones of the upper part of the Sinyavsky series within the Rostov projection, Ukrainian shield. Uncomfortable upper and lower parts differ in the alkalinity type of clastic rocks. The lower part is characterized by potassium alkalinity type (Na2O/K2O < 1), the upper part displays abnormal sodium type (Na2O/K2O > 1). It is shown that rocks enrichment in sodium occurred as a result of epigenetic albitization due to sedimentogene sodium chloride of pore waters. Under metamorphism conditions, sodium is fixed in the newly formed albite while chlorine, without forming its own mineral phase, saturates the pore solution and, with its selectively high activity in respect to gold, contributes to its leaching and redistribution within the entire thickness, thereby creating prerequisites for ore cluster formation.
