Аннотация:The Northeastern Transbaikalia is one of the largest
metallogenic provinces in Russia. It comprises three
world-class deposits: Fe-Ti-V Chiney, Zr-Ta-Nb Katugin,
and Cu Udokan. Besides these giant deposits there are
many small deposits and prospectings in this area. All
these deposits belong to the Paleoproterozoic epoch.
New data on the structure, geochemistry, and mineralogy
of these deposits were obtained by authors for the last
three decades. The main results demonstrate the huge
volume of basic-ultrabasic magmas intruded in sedimentary
rocks of the Udokan Supergroup. They formed intrusive
bodies; part of them are exposed on the surface as
the Chiney, Luktur, and Mylovskiy layered mafic-ultramafic
plutons. The chemical and mineralogical similarities
of massifs demonstrate the common source of their
parental magmas. It was found that Cu deposits in sandstones
are characterized by different chemical ore compositions
(Cu, Ag, Fe, Bi, Ni, Co, PGE) that demonstrate
the essential role of hydrothermal processes in their origin,
especially in Pravoingamakitskoe deposit. It was
suggested that not only magmatic fluids but metheoritic
water took place in ore origin due to their involving in
circulation under heating caused by a huge magmas volume
intrusion. Thus, the modern look of the deposits is a
result of many long-lived geological processes operating
in this area.