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ISSN 1075-7015, Geology of Ore Deposits, 2006, Vol. 48, No. 2, pp. 108–133. © Pleiades Publishing, Inc., 2006.
Original Russian Text © E.O. Groznova, M.G. Dobrovol’skaya, V.A. Kovalenker, K.V. Davydov, V.T. Bitarov, M.V. Razin, 2006, published in Geologiya Rudnykh Mestorozhdenii,
2006, Vol. 48, No. 2, pp. 126–154.
INTRODUCTION
Numerous Pb–Zn deposits (Sadon, Verkhnii and
Nizhnii Zgid, Arkhon, Kholst, and others) have been
known in the Sadon ore district, North Ossetia (Fig. 1)
for more than 150 years.
Extensive geological exploration of this district,
combined with geological mapping on various scales
and specialized geophysical surveying and geochemical
exploration of the adjacent areas, was conducted in
the last century. These works were aimed at providing
the Electrotsink plant in Vladikavkaz with ore. During
this period, geologists managed to establish the main
metallogenic features of the region and particular
deposits therein (Vardanyants, 1935; Chernitsyn, 1985);
to provide insights into the geological and structural
conditions of the ore localization (Gurbanov and Zembatov,
1978; Konstantinov, 1971; Nekrasov, 1980;
Bashkina, 2002); and to determine the composition,
zoning, and genesis of ore mineralization (Zlatogurskaya,
1958; Prokopenko, 1958; Sorokin, 1958; Chernopyatov,
1958; Khetagurov and Katova, 1972; Granovsky,
1982; Davydov and Granovsky, 1985; Dobrovol’skaya,
1987, 1989; Lyakhov et al., 1994).
Corresponding author: E.O. Groznova. E-mail:
[email protected]The forecasting of the hidden mineralization was of
great importance to the Sadon ore district (Azhgirei,
1958; Zlatogurskaya, 1960; Konstantinov, 1971; Konstantinov
et al., 2003). Azhgirei (1958) suggested that
the hidden deposits are controlled by transverse dislocations
and regarded the Dzhimidon area at the eastern
plunge of the anticline as the most promising target. Konstantinov
(1971) considered the contact zone between
Paleozoic granitoids and overlying volcanic sequences as
favorable for localization of Pb–Zn mineralization, including
hidden orebodies.
The expansion of prospects of the ore district at the
expense of hidden ore mineralization was confirmed by
further geological exploration. In particular, the blind
Yuzhny vein was found at the eastern flank of the
Arkhon deposit in the early 1960s, while the hidden
Bozang zone of high-grade Pb–Zn ore was discovered
in the Dzhimidon ore field in the mid-1980s.
The Bozang, Tsagarsar, and East Dzhimidon ore
zones are presently known within the Dzhimidon
deposit. The Bozang ore zone is the reference hidden
ore object in the Sadon district. The study of the geology,
orebody morphology, geochemical halos, wall
rock alteration, and ore composition in the Bozang
Mineralogy and
PT
Formation Conditions of Lead–Zinc Ore
at the Dzhimidon Deposit, North Ossetia
E. O. Groznova
a
, M. G. Dobrovol’skaya
a
, V. A. Kovalenker
a
,
K. V. Davydov
b
, V. T. Bitarov
b
, and M. V. Razin
a
a
Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry, Russian Academy of Sciences,
Staromonetnyi per. 35, Moscow, 119017 Russia
b
Sevosgeologorazvedka Federal State Unitary Geological Enterprise, pr. Kosta 82, Vladikavkaz,
362008 Republic of North Ossetia–Alania, Russia
Received August 10, 2005
Abstract
—The mineralogy and
PT
formation conditions of the Dzhimidon Pb–Zn deposit in the Sadon ore district
are considered. The deposit is localized in metamorphic rocks of the Buron Formation, which pertain to
the pre-Jurassic basement (lower structural stage) and are cut through by Upper Paleozoic granitoids, and in the
Lower Jurassic terrigenous sequence (upper structural stage). Orebodies as quartz–sulfide veins are mainly
hosted in the metamorphic rocks. Galena, sphalerite, chalcopyrite, pyrite, pyrrhotite, and arsenopyrite are the
most abundant sulfides, while quartz, carbonates, chlorite, sericite, and feldspar are gangue minerals. The bismuth
mineralization identified at this deposit for the first time is represented by diverse phases of the Ag–Pb–
Bi–S system. Five stages of the ore deposit formation are recognized: a premineral stage (quartz–feldspar),
three ore-bearing stages (pyrite–arsenopyrite, pyrrhotite–chalcopyrite–sphalerite, and arsenopyrite–sphalerite–
galena), and a postmineral stage (quartz–calcite); each stage comprises one or several mineral assemblages. The
study of fluid inclusions in quartz, calcite, and sphalerite of the premineral, ore-forming, and postmineral stages
has shown that the ore was deposited mainly from Na chloride solution with a salinity varying from >22 to