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The results of the study of the distribution of gold and silver in the main sulfide minerals of the Kadjaran mine of the copper-molybdenum-porphyry formation are presented. The regularity of the behavior of gold and silver was revealed and a forecast estimate of the gold-silver content of the lower horizons of the deposit was given. Gold and silver are unevenly distributed in the vertical range of horizons 2175-1965 m (above sea level). At the upper horizons (above the 2175 horizon), Au and Ag show selective accumulation in chalcopyrite, at the lower horizons (2150-2050 m), in addition to chalcopyrite, they also accumulate in pyrite and molybdenum; moreover, with depth (2050-1985m), the storage capacity of molybdenum and chalcopyrite continues to increase. А significant enrichment of the lower horizons of the deposit (below the horizon of 1965 m) with Au and Ag is unexpected, since their contents are largely limited by concentrations of copper ores, the ratio of which to molybdenum steadily decreases with depth. The studies carried out on distribution of Au and Ag in the main industrial sulfides of Kadjaran copper-molybdenum deposit made it possible to single out the main patterns of their distribution., Periodico di Mineralogia, Vol. 92 No. 1 (2023)

In this contribution, we focus on the Oligocene to Miocene structural evolution of the giant Kadjaran porphyry Cu-Mo deposit and its epithermal overprint. This evolution was controlled by long-lived regional faults during the Cenozoic tectonic and magmatic evolution of the Meghri-Ordubad composite pluton located in the southernmost Lesser Caucasus. We discuss the ore-bearing fracture network characteristics related with the deposit-scale ore-controlling structures in the frame of regional strike-slip faults. Stereonets summarizing the orientations of different generations of mineralized veins allow us to constrain the favorable fracture network environment for ore-formation at the giant Kadjaran deposit. During the middle - late Oligocene, NNE-oriented shortening created the major ~N-S- and NE-oriented steeply dipping ore-controlling deposit-scale faults under dextral strike-slip tectonics. The gently to moderately dipping NE-, ~N-S- and ~E-W-oriented fracture networks along the steeply dipping deposit-scale faults were the most important structural control for the emplacement of the main porphyry stockwork mineralization. These deposit-scale ore-controlling faults were reactivated during the early Miocene under WNW-oriented shortening and NNE-oriented extension. The progressive anticlockwise rotation of paleostress orientations from middle - late Oligocene to early Miocene was linked to re-organization of tectonic plates during Arabia-Eurasia collision.

Степень разрушений и потерь, вызванных Спитакским землетрясением 1988 г., и ее магнитуда ( M = 6.9) были несоизмеримы. Очень важно знать, каков реальный уровень сейсмического риска г. Гюмри (бывш. г. Ленинакан) в настоящее время, каких потерь можно ожидать, если подобное или более сильное землетрясение произойдет в наши дни. Авторами для г. Гюмри разработаны наиболее вероятные сценарии землетрясений путем комплексной оценки сейсмической опасности. На основе анализа реальных данных потерь и разрушений, вызванных Спитакским землетрясением, выбраны подходящие параметры для оценки уязвимости зданий и сооружений региона, которые необходимы для применения в программном комплексе ELER. Для трех выбранных сценариев землетрясения в пределах г. Гюмри с помощью программного комплекса ELER определены потери и различные степени разрушения зданий и сооружений. The degree of damage and losses caused by the Spitak earthquake (1988) and its magnitude ( M = 6.9) were not commensurate. It is very important to know what the real level of seismic risk in Gyumri city (former Leninakan city) is now, and what losses the city could expect if a similar or stronger earthquake occurred nowadays. To answers this question the scenarios of the most probable earthquakes for Gyumri city has been developed based on a comprehensive assessment of seismic hazard. Based on the analysis of real data on losses and damages caused by Spitak earthquake, the correct values of the required parameters used in ELER software for assessing the vulnerability of buildings and structures of the region have been selected. For the three selected earthquake scenarios of the Gyumri city the expected losses and varying degrees of damages have been calculated using ELER software. Степень разрушений и потерь, вызванных Спитакским землетрясением 1988 г., и ее магнитуда ( M = 6.9) были несоизмеримы. Очень важно знать, каков реальный уровень сейсмического риска г. Гюмри (бывш. г. Ленинакан) в настоящее время, каких потерь можно ожидать, если подобное или более сильное землетрясение произойдет в наши дни. Авторами для г. Гюмри разработаны наиболее вероятные сценарии землетрясений путем комплексной оценки сейсмической опасности. На основе анализа реальных данных потерь и разрушений, вызванных Спитакским землетрясением, выбраны подходящие параметры для оценки уязвимости зданий и сооружений региона, которые необходимы для применения в программном комплексе ELER. Для трех выбранных сценариев землетрясения в пределах г. Гюмри с помощью программного комплекса ELER определены потери и различные степени разрушения зданий и сооружений. Russian Academy of Scienses