Viktor E. Chain Boeken

Having accepted an offer from Gebriider Borntraeger Publishing House to write on the geology of the USSR, I recognize the absence of recent works available outside the country. Many scientists struggle to access extensive Soviet literature due to language barriers. The last significant English translation was NALIVKIN's "Geology of the USSR," published in 1960, and since then, new data have emerged that challenge previous concepts across various Soviet regions. Notably, the understanding of the fold system structure has evolved with new theoretical geology insights, acknowledging the role of overthrust nappes and detailed studies of ophiolitic complexes as remnants of oceanic crust. Paleomagnetic studies indicate significant horizontal movements of ancient cratons. This work emphasizes tectonic structure, paleotectonics, and lithological formations, omitting detailed stratigraphic and paleontological data to maintain brevity. Readers are directed to comprehensive resources like "Geology of the USSR" and "Stratigraphy of the USSR" for further information. The publication also references the "Atlas of Lithologic-Paleogeographic Maps of the USSR" for paleogeography insights. The second part, expected in winter 1986/87, will cover Mesozoic and Cenozoic structures, including geosynclinal evolution and plate tectonics, appealing to geoscientists and related fields.

The first part of the ? Geology of the USSR? was published in 1985. Preparation of the second part took 8 years and was completed after the USSR ceased to exist. As such, the title of the second volume will be different but the area treated remains the same. During these years the geosciences have also continued to evolve as did the attitude of scientists involved in the process. For example, the geosyncline concept is now considered obsolete by the majority of workers. Nonetheless, the term geosyncline has been retired without creation of a new term for the initial stage of mobile belt development characterized by extension, spreading, subsidence, deep- water marine sedimentation and submarine volcanism. The terms ? fold belt? or ? orogen? are not, appropriate because not all orogens, such as the Central Asiatic Orogen, evolved from oceanic basins but from intracontinental areas instead. Due to the lack of a better designation the author has chosen to retain the terms ? geo-synclinal belt? and ? geosynclinal system?. But the use of these terms does not imply their fixist interpretation.