Diversity of Gold Deposits, Geodynamics and Conditions of Formation: A Perspective View

Abstract

Gold occurs in a wide range of deposit types and settings. In the last decade, significant progress has been made in the definition, classification, characterization, thereby aiding understanding of the main gold deposit types. The present work aims to provide an update on the current state of knowledge on the different types of gold deposits models, geodynamics, their mode of formation and the condition suitable for their formation Several subsets of gold deposits are distinguished from one another on the bases of and their main geological models and their mode of formation described. Gold deposits of magmatic-hydrothermal origin are classified into Porphyry, Epithermal, Skarn, Iron Oxide-Copper-Gold and Intrusion related deposits; those of hydrothermal origin are Orogenic, Volcanogenic Massive Sulphide deposits, and Carlin-type; while those of Sedimentary Origin are placers. In terms of the major Period of gold deposit formation, the Mesoarchean was the largest gold period. Other gold peaks followed, particularly in the Neoarchean, Paleoproterozoic and Paleozoic while numerous and diverse gold deposit types were formed during the Cenozoic era.Wide varieties of geodynamic contexts in which each of the gold deposits are formed being explained while the conditions favourable for its formation are also being summarized. With the recent rise in the price of gold, mining companies and research centers continue to provide lighting of the key geology features of then ore-forming environments and the key geologic manifestations of the different deposit types.

Typomorphism of Native Gold (Geological-Industrial Types of Gold Deposits in the North-East of Russia)

“…For gold-quartz veins GIT deposits localized in granitoids, the structure of native gold is coarse-grained with rare simple and polysynthetic twins and patchy heterogeneity, presumably associated with the incorporation of microparticles of native Bi, which, unlike gold, undergoes intense etching even in air (Figure 7). A similar type of patchy heterogeneity for gold from deposits in granitoids was previously described in [8].…”

“…V.M. Kreiter's followers continued working in this direction [3][4][5][6][7][8]. They showed that the geological and industrial grouping of deposits is determined by their geological homogeneity and belonging to certain gold formations-groups of deposits with a similar material composition of ores and genesis.…”

Stages of Gold Deposits Formation in the Precambrian of the North-Eastern Fennoscandia

“…Two main stages of the formation of gold deposits are identified in the north-eastern part of the Fennoscandian Shield, the Neoarchean and the Paleoproterozoic, and these stages correspond well to the main global stages of gold deposit formation in the Precambrian (2.7-2.5 and 2.1-1.8 Ga [87][88][89][90]). The Paleoproterozoic stage was more important in the region, as, at this stage, the gold deposits formed not only in the Proterozoic greenstone belts, but in those Archean belts as well, which were involved in the Svecofennian tectonic processes in Paleoproterozoic.…”

Gold in Ferromanganese Deposits from the NW Pacific

“…The highest gold concentrations (up to 230 ppm) have been observed within the Papua New Guinea economic zone near Lihir Island [17]. The maximum Au content in this deposit is comparable to the content in bonanza gold deposits [3].…”

“…The sources of gold deposits are rocks with gold concentrations exceeding those of the earth's crust contents by 2-3 times or more. In nature, there are several mechanisms for the extraction and transport of gold from the mantle and from rocks of various geneses by hydrothermal fluids, including from lithified marine deposits, starting with the Precambrian [2,3]. At the same time, in many continental regions of the world, there are deposits with hyperenrichment of quartz veins in gold ("bonanza" ores, "bonanza" veins) [4,5] The concentration of gold in river water is 0.0001 µg/L, and in the ocean it is 0.00002 µg/L or 0.0000001 µmol/L [6].…”