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Vol. 19 (2016 year), No. 1, DOI: 10.21443/1560-9278-2016-1/1
Chernikov A. G., Libina N. V.
Prediction of structure and properties
of the deep array near the Kola uperdeep well
A new technique for building a model of the internal structure of rock mass has been developed. It is based on using the properties of Markov processes and data processing the earth's surface topography. The paper shows the opportunities of calculating speed 3D models and some of the cross-sections on the example of the area near the Kola superdeep well
(in Russian, стр.0, fig. 0, tables. 0, ref 0, Adobe PDF, Adobe PDF 0 Kb)
Vol. 21 (2018 year), No. 1, DOI: 10.21443/1560-9278-2018-21-1
Libina N. V., Nikiforov S. L.
Ice gouging effects on the eastern Arctic shelf of Russia
Results of the latest geological and geophysical marine cruises indicate activating of natural risks (or hazards) processes connected with ice gouging, permafrost melting, landslides, coastal thermoerosion and seismic activity. These processes represent great risks for all human marine activities including exploitation of the Northern Sea Route (NSR). One of the most dangerous natural processes is ice gouging, which results in the ploughing of the seabed by an underwater part of ice bodies. Ice gouging processes can create some emergency situation in the construction and operation of any underwater engineering structures. Natural seismoacoustic data obtained within the eastern Arctic shelf of Russia have recorded numerous ice gouging trails both in the coastal shallow and deep parts of the shelf as well. Modern high-resolution seismic devices have allowed receive detailed morphology parameters of underwater ice traces. The actual depth and occurrence of traces of the effect of ice formations on the bottom significantly exceed the calculated probability of occurrence according to ice conditions. Seismic data have allowed classify all these traces and subdivide them on modern coastal and ancient (or relict) deep ones. During Late Quaternary sea level down lifting the absence of cover glaciation did not exclude the presence of powerful drifting ice that produced ice gouging processes in the present deep part of the sea. Afterwards during sea level up lifting ice gouging follows to the sea level changes. In this case there could be destructed some dense clay dewatered sediment layer formed during the regression period. Further, during the repeated transgressive-regressive sea level fluctuations the generated ice traces could be frozen and thus preserved until our days. Modern coastal ice traces into marine shallow are the result of nowadays interaction of drifting ice and seabed that in conditions of global climate warming are activated and represent natural risks along the NSR.
(in Russian, стр.10, fig. 8, tables. 0, ref 20, adobe PDF, adobe PDF 0 Kb)
Vol. 22 (2019 year), No. 1, DOI: 10.21443/1560-9278-2019-22-1
Ul'yantsev A. S., Chickiryov I. V., Nikiforov S. L., Sorokhtin N. O., Melousov A. А., Ananiev R. A., Dmitrevsky N. N., Libina N. V.
Lithological characteristics of the modern sediments of the Pechora Sea
The Pechora Sea is of great economic importance for the Russian Federation. Knowledge of the history of the shelf of the Russian Western Arctic seas is impossible without studying the modern processes of sedimentation and lithological structure of the sections. Therefore, the spatial distribution and variety of types of bottom sediments was studied by direct methods of geological testing in August – September 2018 during the 38 route of the research vessel "Academician Nikolai Strakhov". The link of lithological types of bottom sediments to the forms of bottom topography of different origin was established. The characteristics of the late Quaternary sedimentary cover in the Pechora Sea were revealed. The sampling of bottom sediments of the Pechora Sea was carried out using a dredger and a shock ground tube. The sampling points were selected based on the materials of continuous seismic profiling and bathymetric bottom survey. As a result of the study, the following types of bottom sediments were identified: pelitic mud, aleurite-pelitic mud, clay, silt, sand, moraine deposits. The lithological characteristic of various types of the Pechora Sea modern sediments has been presented in the paper. It has been shown that in the most shallow water – the southern and central part of the Pechora Basin – psammitic facies dominate. This is connected with the intensive flow of sandy-silt material from the continent due to river runoff. In the northern – the deepest part of the Pechora basin – thin sediments (pelitic and aleurite-pelitic silts) are mainly distributed. The presence of moraine deposits in the southeastern part of the Pechora Sea suggests that there was a glacier here during the Late Valdaian, while the rest of the Pechora Basin was a lowland with a cryoarid subaerial landscape
(in Russian, стр.8, fig. 4, tables. 0, ref 6, Adobe PDF, Adobe PDF 0 Kb)
Vol. 23 (2020 year), No. 1, DOI: 10.21443/1560-9278-2020-23-1
Chickiryov I. V., Ulyantsev A. S., Nikiforov S. L., Sorokhtin N. O., Ananiev R. A. , Dmitrevsky N. N., Libina N. V., Kovalev G. A.
Comparative lithological characteristics of modern sediments of the Kara and Pechora Seas
Global climate warming and increased anthropogenic pressure on the Arctic shelf contribute to the development of thermoabrasive processes along the coast of the western sector of the Russian Arctic.Comprehensive geophysical, hydroacoustic, geological-geomorphological, and hydrophysical scientific studies were carried out within the Kara and Pechora Seas in June – July 2019, during the 41st cruise of the R/V Akademik Nikolai Strakhov.To test modern sediments, bottom grabbers and shock tube were used. The sampling points were selected based on the materials of continuous seismic profiling and bathymetric bottom survey.As a result of the studies, mapping of the relief and modern sediments within the Kara and Pechora Seas has been carried out and it has been found that the Pechora basin is characterized by various types of sediments and deposits (pelitic mud, aleurite-pelitic mud, clay, silt, sand, moraine deposits), and the Kara Sea is mainly inhabited by thin sediments (pelitic mud). A small amount of sand and siltstone among the bottom sediments of the Kara basin should be associated with an insignificant introduction of terrigenousclastic material from the continent and its deep water. The wide distribution in the southern and central parts of the Pechora Sea of psammiticfacies is due to its shallow water, intensive supply of a large amount of sand-silty material by river flow, processes of solifluction and thermal abrasion of the coasts. In 2020, the next flight of the R/V Akademik Nikolai Strakhov is planned to continue the study of the upper sedimentary stratum and topography of the seabed of the western sector of the Russian Arctic. The purpose of the study is to substantiate the most likely scenario for the development of changes in the natural environment on the shelf, associated primarily with a reduction in the area of ice cover.
(in Russian, стр.8, fig. 7, tables. 0, ref 9, AdobePDF, AdobePDF 0 Kb)