Oleg Vsevolodovich Levchenko

Russian Academy of Sciences | RAS · PP Shirshov Institute of Oceanology

The 85∘E Ridge associated by the free-air gravity low into a meridional orientation. However, there are two gravity lows south between of 4∘N and 3∘S the nature of which remains a subject of discussion. This article presents the results of density and magnetic modeling based on the data of the expedition SO258/2 with RV Sonne. An analysis of the mo...

The geophysical survey in cruise# 42 of R/V Akademik Boris Petrov (2017) at the polygon near Site 758 ODP clarified significantly knowledge about the bottom topography of the northern segment of the Ninetyeast Ridge. It is crossed by E–W transversal linear troughs, apparently being young tectonic fractures. The morphology of the narrow elevated blo...

This paper provides information on the integrated geophysical, sedimentological, and hydrophysical investigations, passing meteorological and biological observations in the Eastern Tropical Atlantic during the cruise 63d of the R/V “Akademik Ioffe” in October–December 2022. The preliminary scientific results are discussed.

A combination of a high sediment input and intense bottom currents often leads to the formation of contourites (sediments deposited or significantly reworked by bottom currents). Both of these components are present in the Vema Fracture Zone valley which is the most important passageway for the distribution of the Antarctic Bottom Water from the We...

The linear Ninetyeast Ridge (NER) is the longest oceanic intraplate volcanic edifice and main feature in the Eastern Indian Ocean. Many seamounts are located on the ridge, whose origin and age remain unclear due to the lack of samples of the bedrock of which they are composed. Carbonate sedimentary caps on these seamounts prevent their direct geolo...

High fluvial input combined with specific topographic and oceanographic settings in the Caspian Sea create favorable conditions for contourite deposition. For the first time in its middle portion, contourite deposits have been observed in high-resolution seismic profiles. Various types of contourite drifts and mixed depositional systems have been r...

Contourites are sediments deposited or substantially reworked by the persistent action of bottom currents which are capable of forming a wide range of erosional and depositional features on the seafloor. The study of contourites is a multidisciplinary topic linking physical oceanography and marine geology. While near-bottom circulation is an import...

A zircon with an age of ~2.9 Ga, much older than all existing dates, has been discovered for the first time in basalts of the Afanasy Nikitin Rise. Such an ancient age is typical of continental crust rocks of Western Hindustan or Antarctica. Analyses have revealed the geochemical similarity of magmas of the Conrad and Afanasy Nikitin rises and thei...

On August 6, 2021, the chief researcher of the IO RAS, Doctor of Geological and Mineralogical Sciences, Professor Ivar Oskarovich Murdmaa turned 90 years old. The main focus of I.O. Murdmaa is the study of bottom sediments of seas and oceans, their lithology, mineralogy, deposition processes, facies and formations, the theory of oceanic sedimentoge...

The study of geomorphology and seismic structureSeismic structure of the Ioffe Drift area was undertaken on the basis of high-resolution sub-bottom profiling data, an old low-resolution single-channel seismic profile, and single-beam and multibeam bathymetric data. The drift occupies the central part of a tectonic ridge related to the Florianopolis...

The focus area of this monograph is the central part of a tectonic ridge within the Florianopolis (Rio Grande) Fracture ZoneFracture zones in the southern Brazil BasinBrazil Basin. The ridge is swept by the bottom current of the Lower Circumpolar Deep WaterLower Circumpolar Deep Water (LCDW) propagating from the Argentine BasinArgentine Basin to th...

По результатам научно-исследовательских экспедиций ИО РАН (2010-2017 гг.) в Центральной и ЮЗ Атлантике с использованием узколучевого параметрического профилографа SES 2000 deep составлен атлас наиболее типичных волновых картин (акустических образов) отложений верхней части осадочного чехла. Атлас содержит более примеры акустических образов с описан...

The Osborn Plateau is a large intraplate elevation in the eastern Indian Ocean, which has been poorly studied by geological and geophysical methods. On cruise SO258/1 aboard the R/V Sonne, new data were collected by Parasound seismic processing, multibeam survey, and, for the first time, dredging. Faults in the sedimentary cover, which extend to th...

According to the data of hydro-magnetic surveying and satellite altimetry, using the original technology for solving the inverse problem, 2D models of the magnetic layer for three latitudinal profiles crossing the submarine plateau of Osborne in the southern, central and northern parts were constructed. Density modeling for these three profiles was...

High-resolution seismoacoustic and multibeam data revealed a large field of sediment waves covering the Santa Catarina Plateau on the Brazilian Southern Margin. Within the field several zones were determined: a zone of large sediment waves (up to 70 m in height), a zone of smaller sediment waves (15–30 m in height) and a zone of buried sediment wav...

After a long break, during the 42nd cruise of R/V «Academic Boris Petrov» (2017), the Shirshov Institute of Oceanology RAS has resumed full-scale geophysical research in the Indian Ocean. Along with bathymetric and seismoacoustic surveys, the cruise resulted in more than 10 000 km of profiles obtained during the modular hydro-magnetic survey. The m...

The Osborne Plateau is a large intraplate elevation in the eastern part of the Indian Ocean, which has been poorly studied by geological and geophysical methods. In cruise SO258/1 on RV Sonne, were collected new data with Parasound seismic profiling and multi-beam echo sounder survey. Fractures in the sedimentary cover, which extend to the bottom su...

Studies of acoustic anomalies in the water column and seismoacoustic anomalies in the Quaternary sediments of Pechora sea and their relationship with deep hydrocarbon sources were conducted by the Institute of Oceanology of the Russian Academy of Sciences and the Geological Institute of the Russian Academy of Sciences in the 38th cruise of RV “Acad...

New geophysical data were obtained in 2017 in cruise #SO258/2 of RV Sonne in the Central Indian Basin between 81° and 84°E. Total length of collected geophysical profiles (bathymetry, seismoacoustic profiling, magnetometry, gravimetry) is about 6,500 miles. Deep seismic sounding was carried out along N-S profile by 375 m long, which extends on the...

New geological-geophysical data were obtained during Cruise SO258 leg 1 of the R/V SONNE carried out in the eastern part of the Indian Ocean in 2017. This expedition was part of the research project INGON, which is a collaboration between the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI) and the GEOMAR Helmholtz Cent...

Cruise SO258/1 of the R/V Sonne (Germany) along a route from Fremantle, Australia, to Colombo, Sri Lanka, was carried out between June 7 and July 9, 2017 for geological and biological research in the Eastern Indian Ocean. The scientific staff included 33 researchers from ten countries (Germany, Australia, USA, UK, Switzerland, France, Taiwan, Canad...

The 42nd cruise of RV Akademik Boris Petrov was carried out from January 5 to March 29, 2017 along the route Tianjin (China) – Singapore - Suez (Egypt) - Kaliningrad (figure), in which studies of the lithosphere, hydrosphere and atmosphere were made. The expedition was carried out simultaneously with return of the vessel back to Russia (Kaliningrad...

Комплексными исследованиями (эхолотирование, сейсмопрофилирование, магнитометрия) в 42 рейсе НИС «Академик Борис Петров» (2017 г.) была исследована подводная гора в основании западного склона древнего северного сегмента Восточно-Индийского хребта в районе 0.5° с.ш. В результате выполненных исследований выявлены особенности морфологии, разломной тек...

A high resolution seismic survey carried out by the Shirshov Institute of Oceanology, Russian Academy of Sciences in 2004–2012 near the foot of the continental slopes of the Derbent Basin (Middle Caspian) revealed evidence for active accumulation of contourites in the Pliocene–Holocene. The discovery of these forms and deposits in the Middle Caspia...

Facts confirming the hypothesis of contourite sediment infill of the Equatorial Mid-Ocean Canyon (EMOC) are presented. We examined two cores recovered in Cruises 37 and 43 of the R/V Akademik Ioffe (2012, 2013). The cores recovered upper Quaternary miopelagic clays on the EMOC floor (AI-3149) and the adjacent abyssal plain (AI-2620). The study of t...

Petrological–geochemical study showed that the alkaline-ultramafics of the Jetty Oasis (rift zone of the Lambert glacier, East Antarctica) are similar in the age (117–110 Ma) and geochemistry to the ultrapotassic alkali basalts of eastern India (Jharia and Raniganj intrusions). Alkaline magmatism in India and Antarctica is related to the activity o...

The study of magmatism and tectonic structure of the East Indian or Ninetyeast Ridge (NER) reveals the geochemical similarity of mantle sources for the NER and Kerguelen Plateau melts. Magmas related to the Kerguelen plume were derived from an enriched mantle source, whereas the NER tholeiitic basalts originated from a source contaminated by a depl...

The high-resolution SES-2000 deep seismic profiles performed by R/V Akademik Ioffe (2010) recorded a calcareous contourite drift over the Florianopolis fracture zone ridge, South Atlantic, named the Ioffe Drift. Core AI-2436 retrieved from the drift summit recovered calcareous nannofossil–foraminiferal ooze contourites with small amounts of fine-gr...

The main goal of this work is to gain better understanding of interplay between gravity-driven sedimentation processes and those related to bottom currents on the Brazil continental rise during the Late Quaternary. The study embraces an area close to the Sao Tome seamount (21°-23° S) that is located on the continental rise in the SW Brazil Basin (S...

A digital elevation model (DEM) of the White Sea has been constructed based on navigational maps on different scales. The maps have been scanned, and their raster images have been processed. The isobaths have been vectorized, and attribute tables have been created. The vector layers have been transformed from map projections to geographical coordin...

The high-resolution seismic profiling during cruise 32 of the RV “Akademik Ioffe” (2010) discovered a large elongated contourite drift on the ridge of the Rio Grande fracture zone (Brazil Basin, western South Atlantic). This sedimentary body with a thickness up to 300 m, named Ioffe drift, is traced at water depth range from 3790 to 3980 m. Five se...

La presa Cerro Prieto, relativamente una pequeña reserva de agua en el noreste de México, es uno de los principales recursos de agua potable para Monterrey, ciudad con una población cerca de cuatro millones de habitantes. Se llevó a cabo un estudio de sísmica de alta resolución en esta reserva de agua con un equipo SES-2000 que utiliza un efecto ac...

New multibeam bathymetry data and multichannel seismic profiles over 7 detailed survey sites collected during cruise no. KNOXRR06 of the R/V Rodger Revelle in 2007 fundamentally expanded the concepts about the structure of the sedimentary cover of the Ninety-East Ridge, which were based on the results of previous studies. They allow making a step f...

Seismoacoustic investigations with a high-resolution parametric echo-sounder “SES 2000 deep” carried out on cruises 33, 35, and 37 of the R/V Akademik Ioffe revealed several erosional-depositional contourite systems on the São Paulo Plateau escarpment and its toe in the South Atlantic. Two contourite terraces related to interfaces between different...

In the period from September 23 until October 21, 2011, during the 35th cruise of the R/V Akademik Ioffe, combined with the vessel being run in the begin� ning of the 2011–2012 tourist season in the Antarctic, the regular studies in the framework of the seismofa� cies analysis of the Atlantic’s Quaternary deposits dur� ing transatlantic runs were p...

Altogether, 16 specialists participated in the expe� dition: seven from the Institute of Oceanology of the Russian Academy of Sciences, three from the Institute of Geology of the Russian Academy of Sciences, three from the Institute of Atmosphere Physics of the Rus� sian Academy of Sciences, two from Pomeranian Uni� versity, and one from Innomar Te...

High-resolution seismic profiles collected by Parasound and SES-2000 deep profilers during Cruise 26 of the R/V Akademik Sergei Vavilov (2009) along the continental slope base of South America, NW Africa, and West Europe are correlated with the deep-sea drilling boreholes. Lithofacies interpretation of the Quaternary deep-water seismic facies of he...

Acoustically stratified seismic images are widely used in studies of sedimentation mechanisms producing thick sedimentary aprons on continental rises. However, insuffcient vertical resolution of seismic records commonly restricts a more detailed interpretation of individual reflectors within accumulations to reconstruct specifc short-term sedimento...

Most of the hydrocarbon fields in the oceanic and thinned suboceanic crust are associated with deep-seated faults. This fact might be caused by methane formation under the serpentinization of the upper mantle rocks and its transfer to the sedimentary cover with hydrotherms. The northern part of the Indian Ocean deformation zone may be of considerab...

A major scientific expedition in the Indian Ocean was accomplished onboard RV Roger Revelle (KNOX06RR) to investigate the evolution of the Ninetyeast Ridge and to understand the spreading activity particularly in close proximity to the Kerguelen hotspot. Comparison of the magnetic anomaly data of both the Central Indian and Wharton basins with synt...

The Caspian Sea is a hydrocarbon basin of great value. Its most remarkable geohazards are: shallow gas accumulation, seismicity, gravity mass transport, and near-bottom sediment transport (both water and turbidity currents). Every natural process is responsible for some geological forms, which can be seen on seismic sections. High-resolution seismi...

New high-resolution seismic reflection profiles collected on the western slope of the Caspian Sea during cruises of RV “Rift” in 2004, 2006 and 2007 allowed the identification of regional sedimentary processes formed its present morphologic and structural image. The upper, gentle part of the slope, from the shelf edge to 400m water depth, was forme...

The Ninetyeast (or East Indian) Ridge is one of the longest aseismic volcanic ridges in the World Ocean and one of the longest linear structures of the Earth. It is 200 km wide on average, and it extends in the meridional direction via the entire eastern part of the Indian Ocean for almost 5000 km. The ridge is distinctly expressed in the bottom to...

Ninetyeast Ridge (NER) is a linear volcanic ridge in the Indian Ocean thought to have formed by hotspot volcanism on the northward?drifting Indian plate. Geological data from the ridge are sparse, so its tectonic evolution is poorly known. We studied satellite-derived gravity data, seismic reflection profiles, and multibeam bathymetry to examine NE...