Baku State University, Baku, Azerbaijan

N. A. Imamverdiev, Head of Department, Professor, Doctor of Geological and Mineralogical Sciences, inazim17@yahoo.com

T. G. Takhmazova, Associate Professor, Doctor of Philosophy in Earth Sciences

Azerbaijan State Oil and Industry University, Baku, Azerbaijan
V. M. Kerimov, Associate Professor, Candidate of Geological and Mineralogical Sciences
N. V. Pashaev, Dean, Associate Professor, Candidate of Geological and Mineralogical Sciences

The article discusses origin of epithermal gold and silver deposits in the Agduzdag ore field, Lesser Caucasus, Azerbaijan, and its potential prospects. It is found that low-temperature gold and silver, mercury and, probably, mercury–arsenite–antimony and copper–lead–zinc deposits and mineralizations of the Lesser Caucasus are connected in time with Neogene medium-acid rocks of high-potassium calc–alkaline magmatism. In faulting zones, these rocks experience hydrothermal alteration with formation of alternating facies of low-temperature propylite and quartzite. Gold mineralization is mainly connected with post-magmatic activity of subvolcanic Miocene–Pliocene formations. The explanatory arguments are: the close spatial relationship between the hydrothermally altered zones and subvolcanic connections; comparatively the same age and the presence of similar minerals and admixtures in compositions of ores and rocks; finally, the high gold content of subvolcanic rocks, ranging from 1.3–10 g/t at the average value of 5.03 g/t. The gold deposits in the test area adjoin the systems of long-standing north-to-south and north-to-east faults outlined by ring structures, and, mostly, the sites of their intersections. Such faults are the ore-controlling longitudinal Lachin–Bashlybel and lateral Terter faults, as well as the Kazykhanly–Agduzdag, Dalidag, Seutly and Agduzdag–Zog faults and related ring structures. Since Kd < 1, the main valuable elements concentrate not in rock-forming minerals but in residuum. As a result of metasomatic and postmagmatic hydrothermal processes, these elements can form their own deposits and mineralizations. The implemented petrological and geochemical research shows that the test area is promising in terms of new Au-, Ag-, Hg-, A-s, Sb-ore, Au-Cu-Mo-, Au-polymetallic, copper–polymetallic and complex deposits and ore occurrences.

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