Natalia Nikolaeva

• Pacific Oceanological Institute

The main goal of the study is to establish the spatial and temporal distribution of pyroclastic material from large explosive eruptions of the volcanoes of Kamchatka, the Kuril, and Aleutian Islands to create a generalized tephrochronological model and reveal patterns of explosive activity in this region. This paper presents new data on the composi...

The main goal of the study is to establish the spatial and temporal distribution of pyroclastic material from large explosive eruptions of the volcanoes of Kamchatka, the Kuril, and Aleutian Islands to create a generalized tephrochronological model and reveal patterns of explosive activity in this region. This paper presents new data on the composi...

The paper presents the results of multidisciplinary studies in the carbonate–barite mineralization area revealed on the western slope of the Kuril deep-water basin in the Sea of Okhotsk. Findings of carbonate concretions and barite in different age (Miocene–Holocene) deposits indicate that the bottom of this area hosted a long-lived center of gas–f...

The mineral composition of the heavy subfraction from surface sediments of the Okhotsk Sea was studied using both two detailed profiles (Magadan-Kuril Islands and Shantar Islands-Central Basin) and data from the Sakhalin Bay. The obtained data were analyzed using the methods of multivariate statistics, which allowed to identify the main association...

This paper is based on the results of a comprehensive investigations of sediments from seven cores sampled during the International Russian-Chinese Cruise 53 of the R/V “Akademik Lavrentyev” (2010) in the frames of the Russian-Chinese collaboration between the Pacific Oceanological Institute of the Far-Eastern Branch of the Russian Academy of Scien...

Tephra layers within marine sediments provide information on past explosive eruptions, which is especially important in the case of remote island arcs where data on proximal pyroclastic deposits can be scarce. Three Alaska-Aleutian tephras (labeled Br2, SR2, and SR4) were found in the late Pleistocene-Holocene sediments of the Bering Sea (north Pac...

The fullest summary on composition, age and distribution of 23 tephra layers detected and investigated in the Okhotsk Sea Pleistocene-Holocene deposits is presented. Seven tephra layers are surely identified with powerful explosive eruptions of volcanoes of Kamchatka, Kurile and Japanese Islands. For them, the areas of ash falls including which wer...

Heavy mineral associations from tephra layers in the Quaternary deposits of the Sea of Okhotsk and their chemical characteristics were studied by various techniques. It was shown that such investigations may have a bearing on the problems of tephrostratigraphic correlation. We assessed the possibility of application of the mineral composition of di...

В работе приводятся первые сведения о новом проявлении карбонатно баритовой минерализации, обнаруженной на участке метановых просачиваний в Охотском море на западном склоне Куриль ской котловины. Детально рассмотрены морфологические типы баритов, арагонитов и низкомаг незиальных кальцитов, приводятся результаты изучения изотопного состава углерод...

First data are reported on a new manifestation of carbonate–barite mineralization found at a site of methane emanations on the western slope of the Kuril Basin, Sea of Okhotsk. Morphological types of bar� ite, aragonite, and low�magnesian calcite are considered in detail; the results of carbon and oxygen isotope study of carbonate concretions and c...

First data are reported on a new manifestation of carbonate-barite mineralization found at a site of methane emanations on the western slope of the Kuril Basin, Sea of Okhotsk. Morphological types of barite, aragonite, and low-magnesian calcite are considered in detail; the results of carbon and oxygen isotope study of carbonate concretions and cru...

The mineral composition of the heavy fraction in surface sediments of the Laptev and East Siberian seas has been analyzed. The multivariate statistics methods were used to define the main heavy mineral assemblages with outlining regional differences in their compositions and principal factors responsible for the formation of sediment mineral affini...

The possible reconstruction of ancient sedimentary environments on the basis of heavy-minerals assemblages is presented by means of discriminant lithogeodynamic diagrams that compare modern and ancient sedimentary environments. This is exemplified by Mesozoic-Cenozoic deposits recovered from ODP cores obtained from the Philippine and Japan Seas, th...

The Sakhalin Slope Gas Hydrate Project (SSGH) is an international collaborative effort by scientists from Japan, Korea, and Russia to investigate natural gas hydrates (GHs) that have accumulated on the continental slope off Sakhalin Island, Okhotsk Sea. From 2009 to 2011, field operations of the SSGH-09, -10, and -11 projects were conducted. GH-bea...

Coring and seawater sampling sites

A sequence of 9 ash layers (tephra) found in the Middle-Late Pleistocene and Holocene sediments of the central Okhotsk Sea was established on the basis of glass chemical composition and refractive indices, grain-size distributions and heavy mineral assemblages. Five tephras were also characterized by rare earth element distributions. Volcanic sourc...

A sequence of 9 ash layers (tephra) found in the Middle-Late Pleistocene and Holocene sediments of the central Okhotsk Sea was established on the basis of glass chemical composition and refractive indices, grain-size distributions and heavy mineral assemblages. Five tephras were also characterized by rare earth element distributions. Volcanic sourc...

Manifestations of cold methane seeps, gas hydrates and carbonate precipitates are investigated within northeastern Sakhalin slope. Data on isotopic composition of carbon from methane, carbonate concretions and crusts have showed that methane has mainly biogenic origin due to microbial alteration of the organic matter. Gas composition (including gas...

This paper summarizes the results of combined studies in the areas of the occurrence of gas-fluid emanations in the water column, on the seafloor, and in the upper part of the sedimentary section on the northeastern slope of Sakhalin Island (Sea of Okhotsk). The phenomena typical of methane seeps were characterized in detail: the presence of acoust...

To identify the main sources of terrigenous sediments of the La Paz Lagoon, a description of the hydrology of the drainage basins and the mineralogy of the heavy fraction of the lagoon sediments is needed. In this work, 14 terrigenous sediment samples from the arroyos (dry streams) and 55 superficial marine sediment samples were collected from the...

Heavy mineral data of sediments from the marginal seas of the Western Pacific (Bering, Okhotsk, Japan, East China, Philippine, Banda, etc.), from the Tonga and Vanuatu Trenches and from adjacent areas have been evaluated using multivariate statistics and correlation, factor, cluster and discriminant analyses. The overall characteristics of heavy mi...

This paper reports specific mineralogical and geochemical characteristics of deposits from the local depressions of the Derugin Basin. They were formed in an environment with periodic changes from oxic to anoxic conditions and show evidence for the presence of hydrogen sulfide in bottom waters. The deposits of this type can be considered as a moder...

The distribution of mineral associations in the sediments of the Vietnamese shelf and continental slope is examined. Mineralogical provinces are defined and their characteristics are given. The principal regularities in formation of the mineral composition of sea sediments whose supplying provinces are situated in large part in the subequatorial be...