Sources and Provenances of Late Cenozoic Sand Deposits of the Ol’khon Island (Baikal Rift Zone)

Doklady Earth Sciences - Geochronological (LA–ICP–MS) U–Th–Pb studies of detrital zircon of the Late Cenozoic sand deposits on Ol’khon Island have been performed. It...     

Spatial structure of periodicity in the conifer tree radial increment in the Republic of Komi

Spectral analysis of tree ring data sets of Siberian spruce (Picea obovata) and Scots pine (Pinus sylvestris L.) was carried out to study the effects of climatic factors on the conifer tree radial growth in the territory of the Komi Republic. Analyses were performed for different natural subzones in the Komi Republic: the forest-tundra transition zone and the northern, middle, and southern taiga. The results show that several groups of periodicities can be found in the tree radial growth. One from groups of periodicities is related to internal processes in the atmosphere-ocean system; the other is related to the fluctuations in solar activity.     

Optical properties and crystal chemistry of synthetic rutile implanted with cobalt ions

Implantation of high-energy cobalt ions into plates of synthetic rutile has been studied, and absorption, luminescence, and luminescence excitation spectra have been recorded and interpreted. Long-wave luminescence (820 nm) of Ti _IV ³⁺ ions in rutile has been revealed; its intensity increased after the cobalt implantation. Analysis of luminescence and luminescence excitation spectra has allowed us to specify the scheme of electron energy levels of rutile and to establish the energy levels of impurity Ti³⁺ ions occupying vacant octahedrons with the C _2h symmetry in structure of the mineral.     

New data on continental crust age in the western part of the Aldan Shield: Results of Sm–Nd isotopic study of the Cenozoic sand deposits in the Chara and Tokkin Basins

It has been demonstrated on basis of Sm–Nd isotopic analyses of the Cenozoic sands from the Chara and Tokkin Basins in the eastern flank of the Baikal rift zone that the Chara–Olekma Geoblock of the Aldan Shield is an area of intense crust growing processes occurred not only in the Paleoarchaean but in the Mesoarchaean as well.     

Mammalian Tooth Marks on the Bone of Eutriconodontan Gobiconodon borissiaki (Mammalia,Gobiconodontidae) from the Lower Cretaceous of Mongolia

Doklady Earth Sciences - Tooth marks preserved on a dentary fragment of eutriconodontan Gobiconodon borissiaki Trofimov, 1978 from the Early Cretaceous Zuun-Höövör locality in...     

Two New Localities of Mesozoic Mammals in Russia (Krasnoyarsk Territory,Lower Cretaceous)

Doklady Earth Sciences - Two new localities of Mesozoic mammals have been discovered: Bol’shoi Ilek and the Berezovaya River (Russia, Krasnoyarsk Territory, Lower Cretaceous, Ilek Formation)....     

Geomorphology in the system of Earth sciences

We examine the question of determining the place of geomorphology in the system of Earth sciences. The study revealed that, in spite of the differences in understanding the subject matter of science, there are at least seven integrating and generally accepted techniques of geomorphological investigations themselves: orographic analysis, cartometry, remote analysis of hidden landforms, morphometry, geomorphological mapping, modeling of geomorphological systems and conceptual development of the methodology. Emphasis is placed on the important role of geomorphological mapping in understanding all processes on land cover and the history of its development, assessing the natural resources and natural hazards, and in forecasting the evolution of the landscape. The technique of representing results from geomorphological investigations as a geomorphological map requires developing a classification of topographic features and landforms, and publications of A. N. Lastochkin and his followers are specifically focused on this issue. The integrating role of N. A. Florensov’s ideas of concepts concerning the continental orogenesis and geomorphological formations is pointed out. The autonomy of geomorphology in the system of Earth sciences is demonstrated but it is emphasized that it is not possible to further develop geomorphological knowledge outside the province of related Earth sciences, primarily geology and physical geography. A substantiation is given to the exclusiveness of the object of study (topography of land cover) and the subject (main topographic properties: morphology, genesis, age, and morphogenesis processes) which can be analyzed solely by geomorphological research techniques and development models.