The introduction to the special issue of the journal provides a brief description of the organization of geological education in Irkutsk, closely connected with the development of geological science in the south of Eastern Siberia, the current state of the geological faculty, and the authors' vision of the future faculty in connection with demands for scientific and industrial geological work in society.

The name of the famous geologist and teacher Alexander Vladimirovich Lvov (1871-1941) is well known not only to specialists, but also to everyone who is interested in the history of scientific research in Siberia. Lviv stood at the origins of the creation of geological education in Irkutsk, created a scientific school of engineering geology and permafrost science in Siberia, participated in the study of minerals in the Baikal region and mining conditions of the construction and operation zone of the Trans-Siberian Railway. One of the areas of his research was to participate in the exploration of sites for the construction of hydroelectric power plants in the Angara region.

The history of studying the Botogol graphite deposit has been going on for more than a century. Geologists of Irkutsk State University N.A. Florensov, M.M. Odintsov, V.S. Sobolev and V.P. Solonenko, who later became world-famous scientists, made a great contribution to understanding the genesis and structure of this unique deposit. They worked at the field during the Great Patriotic War, when graphite was a strategic raw material and the country's industry was in dire need of it.

75 years have passed since the discovery of the diamond placer on the Sokolina Spit in the valley of the Vilyu River, located 6 km upstream from the village of Krestyakh, which forced the search to be moved from the territory of the Irkutsk region to the Sakha region (Yakutia). This discovery was made on August 7, 1949 by the party of Grigory Feinstein, who at that time was part of the Tunguska expedition, led by Mikhail M. Odintsov, the initiator of the diamond search on the Siberian platform, who in the autumn of 1949, after defending his doctoral dissertation, was appointed the first dean of the independent geological faculty. 5 years later, on August 21, 1954, a young woman from ALL over Leningrad, Larisa A. Popugaeva, discovered the first indigenous diamond source in Siberia, the Zarnitsa kimberlite pipe, using the pyrope method of searching on the advice of Alexander A. Kukharenko. 70 years have passed since that date.

This paper presents studies of lecturers from the Geological Faculty of Irkutsk State University performed in Mongolia at different times. In 1957–1958, the study of the consequences of the Gobi-Altai earthquake that occurred in Mongolia on December 4, 1957, led to the discovery by N.A. Florensov and V.P. Solonenko of a new scientific direction – paleoseismogeology. The idea of using seismic dislocations newly formed during a strong earthquake to assess past seismic events in the area with similar structures of the geological past was eventually supplemented by American paleoseismogeologists that opened seismic structures by trenches and dated seismic events using the ¹⁴C method. In the 1970s, lecturers of the faculty A.G. Kuznetsov, V.A. Suldin and others participated in the work of the Soviet-Mongolian complex Khovsgol expedition. They compiled a geological map of the Khovsgol region and assessed the territory's prospects for phosphorites and bauxites. These works were of practical importance and served as a basis for hydrogeologists, paleoseismogeologists, biologists, soil scientists, chemists and other specialists, who took part in the expedition's work. In the 2001–2024, the authors of this paper substantiated the spatial and temporal change in mantle sources of volcanic rocks of the latest geodynamic stage of the Earth's evolution in Mongolia and linked the origin of lithosphere deformations in the Baikal Rift System with the development of processes in the Japan-Baikal geodynamic corridor.

At the end of the sixties, the Laboratory for Modeling Geological Processes was created for the purpose of mathematical analysis of oil and gas information.

The article gives a brief characteristic of the work of the department, the history of its organisation, describes the directions of scientific geochemical research, staff composition and academic disciplines on bachelor's and master's degrees in geology and geochemistry, research forms of work with students.

Sixty years have passed since the geologists graduated from Irkutsk State University, but they still warmly remember the time of admission, student life, and the specifics of the educational process. During their studies, thanks to the active and wise participation of the teaching staff, students deservedly approached the level of specialists capable of solving professional production tasks. The successes achieved in the work biography of everyone allow the university and the faculty to be deservedly proud of their graduates.

Educational geological practices are a natural continuation of theoretical classroom training. The article reconstructs the history of their conduct since the founding of the Faculty of Geology of the ISU, describes the main methodological aids, lists all teachers-heads of practices, types and methods of their conduct, as well as gives a brief summary of their psychological and professional peculiarities of their conduct and significance for students — future geologists.

The paper presents a review of Pb isotope data on bitumens, kerogens, and oils. The diagrams of Pb isotopes distinguish isochron families, discrete clusters, and continuous extended trends of data points. Arguments are given in favor of Pb isotopic homogenization with the output of isochron Pb–Pb dating under hydrothermal conditions during lead separation from uranium into ore minerals simultaneously with the enrichment of bitumen with uranium. From families of data points of oils and kerogen, the Pb isotope diagrams reveal discreteness of source components that have not undergone general Pb isotopic homogenization under catagenesis conditions. Continuous, extended trends in Pb isotopes are identified and interpreted in terms of the global evolution of the Earth's mantle and crust. For oils from Europe and adjacent marine areas, Pb-isotope mixture of components is determined. In North Sea, mixing between Precambrian basement rocks and Jurassic black shales is traced that demonstrates a common European oil component (CEOC) that has a high μ (²³⁸U/²⁰⁴Pb) – HIMU and significantly different from the common mantle reservoir (CMR) of intraplate volcanic rocks from Europe with adjacent Africa and Arabia. In contrast to this relationship between components, extended trends of oils from the Liaohe field of Northeast China are similar to those of the ELMU and LOMU mantle components of the Cenozoic volcanic rocks from Asia. It is suggested that bitumen, kerogens, and oils of this field are generated by deep mantle fluid flows. The review was done in frame of the interactive preparation of a paper with master's students of the Geological Faculty of Irkutsk State University.