Показаны фундаментальное и практическое значения этих исследований для решения узловых проблем геологии россыпей. Установлен и исследован особый подкласс аллювиальных россыпей золота, сформировавшийся в условиях нарушения процесса разделение кластогенного материала по гидравлической крупности и выявлены факторы, которые определяют этот процесс, мобильность золота, форму и условия локализации его концентраций.
Ключевые слова: золото, осадочные комплексы Украины, литогенетические процессы, морфология, пробность и гранулометрия золота, морфогенетическая классификация, трансформация золота.
Kovalchuk M.S. Gold in sedimentary complexes of Ukraine.- Manuscript.
The thesis is submitted to get doctor degree in Geology in specialty 04.00.21 - lithology. Institute of Geological Sciences of the National Academy of Sciences of Ukraine, Kyiv, 2003.
Gold-bearing of sedimentary thickness of Ukraine and typomorphizm of native gold contained in it were studied. Temporal, spatial, lithofacial and facial distribution of gold in sedimentary thickness of Ukraine, genetic types of gold-bearing, lithological peculiarities of auriferous complexes were established. Peculiarities of granulometry, morphology, micromorphology of the surface chemical composition of the native gold of different age and polygenetic sedimentary formations of the various structures of Ukraine were considered. New and unusual segregation’s from gold according to these indices were determined. Probable conditions of their forming were observed and the prognosis evaluation of territories for reconnaissance of their native gold-bearing manifestations were established. The granulometric and morphogenetic classifications of gold from sedimentary thickness of Ukraine was worked out for the first time. Six morphologic varieties of native gold (idiomorphic, hypidiomorphic, individuals with signs of skeletal growth and dendritoids, xenomorphic, heamiidiomorphic, fold with big diapasone of forms) are settled and main forms of their segregations (morphology, surface micromorphology, colour, granulometry, assay) are considered. A certain conditions for gold formation of different morphogenetic varieties are ascertained. The gold localization examples of certain morphogenetic types in sedimentary complexws of the Ukraine (region and age of sedimentary complexes) are given. The process of transforming the shape and morphology of the surface of gold in the processes of sedimentogenesis and the role of various factors which determined these processes were studied as well. The fundamental and practical significance of these researches for solving the principal problems in the geology of placer was shown. The special type of forming placers of gold in the conditions of breaking down the process for division of clastogene materials on the hydraulic coarseness was established. Factors determining this process, mobility of gold, shape and conditions of localization’s its concentrations of gold in the hypergenesis zone (area) and in processes of continental and marine sedimentogenesis were observed. The mechanism of gold placers formation associated with crusts of weathering erosion is examined in this paper. The feature of placerformation process is condition disturbance of clastic material division according to hydraulic size; thanks to this fact gold is “swimming” on the surface and carried away by flows of high density and viscosity at great distance. The factors, was influence this processes were considered. In this connection the author suggests to concentrate the gold paleoplacers prospecting in non graded fine-grained and high-clayey formations of fluvial, channel shoal, flood plain, oxbow-lake, lake and deltaic and coastal facies too. The most perspective formation complexes were characterized. The general scheme of the process of gold-bearing forming in them is presented. Geological-genetic types of auriferous formations are established. The reconnaissance criteria were workout (elaborated) and the recommendations for reconnaissance works were given too.