Control of the geomorphology and gas hydrate extent on widespread gas emissions offshore Romania

The Romanian sector of the Black Sea deserves attention because the Danube deep-sea fan is one of the largest sediment depositional systems worldwide and is considered the world's most isolated sea, the largest anoxic water body on the planet and a unique energy-rich sea. Due to the high sediment accumulation rate, presence of organic matter and anoxic conditions, the Black sea sediments offshore the Danube delta is rich in gas and thus shows Bottom Simulating Reflectors (BSR). The cartography of the BSR over the last 20 years, exhibits its widespread occurrence, indicative of extensive development of hydrate accumulations and a huge gas hydrate potential. By combining old and new datasets acquired in 2015 during the GHASS expedition, we performed a geomorphological analysis of the continental slope north-east of the Danube canyon compared with the spatial distribution of gas seeps in the water column and the predicted extent of the gas hydrate stability zone. This analysis provides new evidence of the role of geomorphological setting and gas hydrate extent in controlling the location of the observed gas expulsions and gas flares in the water column. Gas flares are today considered an important source of the carbon budget of the oceans and, potentially, of the atmosphere.

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Marine gas hydrates’ evolution after Middle Pleistocene: basin analysis of the Danube fan, Black Sea

Review of the Bulgarian Geological Society ◽

10.52215/rev.bgs.2020.81.3.184 ◽

2020 ◽

Vol 81 (3) ◽

pp. 184-186

Author(s):

Atanas Vasilev ◽

Nikola Botoucharov ◽

Petar Petsinski ◽

Rositsa Pehlivanova

Keyword(s):

Black Sea ◽

Gas Hydrates ◽

Gas Hydrate ◽

Deep Sea ◽

Geological Structure ◽

Basin Analysis ◽

Middle Pleistocene ◽

The Black Sea ◽

Sea Fan

The aim of this work is to reconstruct the variations of the total gas hydrate (GH) masses of the Danube deep-sea fan after 0.265 Ma BP. The PetroMod™ model developed in GEOMAR, Germany is for basin analysis of the Western Black Sea for 98 Ma. Geological structure is from 2D seismic of the Black Sea consortium “Geology without limits”. Results show a trend for total GH masses decrease after Middle Pleistocene and the role of the GHs as sink and source of methane.

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Niche partitioning of bacterial communities along the stratified water column in the Black Sea

MicrobiologyOpen ◽

10.1002/mbo3.1195 ◽

2021 ◽

Vol 10 (3) ◽

Author(s):

Mariia Pavlovska ◽

Ievgeniia Prekrasna ◽

Evgen Dykyi ◽

Andrii Zotov ◽

Artem Dzhulai ◽

...

Keyword(s):

Water Column ◽

Black Sea ◽

Bacterial Communities ◽

Niche Partitioning ◽

The Black Sea

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Research into Dissociation Zones of Gas Hydrate Deposits with a Heterogeneous Structure in the Black Sea

Energies ◽

10.3390/en14051345 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1345

Author(s):

Oleg Bazaluk ◽

Kateryna Sai ◽

Vasyl Lozynskyi ◽

Mykhailo Petlovanyi ◽

Pavlo Saik

Keyword(s):

Black Sea ◽

Gas Hydrate ◽

Computer Modelling ◽

Interpolation Method ◽

Methodological Approach ◽

The Black Sea ◽

Heterogeneous Structure ◽

Offshore Area ◽

Gas Hydrate Deposits ◽

Hydrate Deposit

Ukraine is an energy-dependent country, with less that 50% of its energy consumption fulfilled by its own resources. Natural gas is of paramount importance, especially for industry and society. Therefore, there is an urgent need to search for alternative and potential energy sources, such as gas hydrate deposits in the Black Sea, which can reduce the consumption of imported gas. It is necessary to refine the process parameters of the dissociation of gas hydrate deposits with a heterogeneous structure. The analyzed known geological–geophysical data devoted to the study of the offshore area and the seabed give grounds to assert the existence of a significant amount of hydrate deposits in the Black Sea. An integrated methodological approach is applied, which consists of the development of algorithms for analytical and laboratory studies of gas volumes obtained during the dissociation of deposits with a heterogeneous structure. These data are used for the computer modelling of the dissociation zone in the Surfer-8.0 software package based on the data interpolation method, which uses three methods for calculating the volumes of modelling bodies. A 3D grid-visualization of the studied part of the gas hydrate deposit has been developed. The dissociation zone parameters of gas hydrate deposits with different shares of rock intercalation, that is, the minimum and maximum diameters, have been determined, and the potentially recoverable gas volumes have been assessed. The effective time of the process of gas hydrate deposit dissociation has been substantiated. The obtained research results of the dissociation process of gas hydrate deposits can be used in the development of new technological schemes for gas recovery from the deep-water Black Sea area.

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The configuration of the Pontus Euxinus in Ptolemy's Geography

History of Geo- and Space Sciences ◽

10.5194/hgss-11-31-2020 ◽

2020 ◽

Vol 11 (1) ◽

pp. 31-51

Author(s):

Dmitry A. Shcheglov

Keyword(s):

Black Sea ◽

The Black Sea ◽

North East ◽

The Earth ◽

Open Sea ◽

Straight Line ◽

Key Points ◽

Similarities And Differences ◽

Types Of Information ◽

Constituent Elements

Abstract. This article aims to explain how Ptolemy could have constructed a map of the Pontus Euxinus (Black Sea), as described in his Geography, under the assumption that his sources were similar to those that have come down to us. The method employed is based on the comparison of Ptolemy's data with corresponding information from other ancient sources, revealing the most conspicuous similarities and differences between them. Three types of information are considered as possible “constituent elements” of Ptolemy's map: latitudes, coastline lengths, and straight-line distances. It is argued that the latitudes Ptolemy used for the key points determining the overall shape of the Pontus (Byzantium, Trapezus, the mouth of the Borysthenes and the Cimmerian Bosporus, the mouth of the Tanais, etc.) were most likely inherited from earlier geographers (Eratosthenes, Hipparchus, and Marinus). In exactly the same way, Ptolemy's data on the circumference of the Pontus and the length of the coastal stretches between the key points (from the Thracian Bosporus to Cape Karambis, Sinope, Trapezus, and the mouth of the Phasis, etc.) closely correlate with the corresponding estimates reported by other geographers (Eratosthenes, Artemidorus, Strabo, Pliny, Arrian, and Pseudo-Arrian), which implies that Ptolemy drew on similar coastline length information. The shortening of Ptolemy's west coast of the Pontus (from the Thracian Bosporus to the mouth of the Borysthenes) relative to the corresponding distances reported by other sources is explained by his underestimation of the circumference of the Earth. The lengthening of Ptolemy's north-east Pontus coast (from the Cimmerian Bosporus to the mouth of the Phasis) can, in part, be accounted for by his attempt to incorporate the straight-line distances across the open sea reported by Pliny. Overall, Ptolemy's configuration of the Black Sea can be satisfactorily explained as a result of fitting contradictory pieces of information together that were inherited from earlier geographical traditions.

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A BEM for the Hydrodynamic Analysis of Oscillating Water Column Systems in Variable Bathymetry

Energies ◽

10.3390/en13133403 ◽

2020 ◽

Vol 13 (13) ◽

pp. 3403 ◽

Cited By ~ 3

Author(s):

Kostas Belibassakis ◽

Alexandros Magkouris ◽

Eugen Rusu

Keyword(s):

Boundary Element Method ◽

Water Column ◽

Black Sea ◽

Bottom Topography ◽

The Black Sea ◽

Device Performance ◽

Oscillating Water Column ◽

Energy Potential ◽

Hydrodynamic Analysis

In this work, a novel Boundary Element Method (BEM) is developed and applied to the investigation of the performance of Oscillating Water Column (OWC) systems, taking into account the interaction of the incident wave field with the bottom topography. The modelling includes the effect of additional upwave walls and barriers used to modify the resonance characteristics of the device and improve its performance as the U-OWC configuration. Numerical results illustrating the effects of depth variation in conjunction with other parameters—such as chamber dimensions as well as the parameters associated with the turbine and power take-off system—on the device performance are presented and discussed. Finally, a case study is presented regarding the potential installation of an OWC in a selected port site in the Black Sea, characterized by a good wave energy potential, on the coast of Romania.

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Modeling the distribution of nitrogen species and isotopes in the water column of the Black Sea

Marine Chemistry ◽

10.1016/j.marchem.2008.01.006 ◽

2008 ◽

Vol 111 (1-2) ◽

pp. 106-124 ◽

Cited By ~ 19

Author(s):

S.K. Konovalov ◽

C.A. Fuchsman ◽

V. Belokopitov ◽

J.W. Murray

Keyword(s):

Water Column ◽

Black Sea ◽

The Black Sea ◽

Nitrogen Species

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Hans Werner Lissmann, 30 April 1909 - 21 April 1995

Biographical Memoirs of Fellows of the Royal Society ◽

10.1098/rsbm.1996.0015 ◽

1996 ◽

Vol 42 ◽

pp. 235-245

Keyword(s):

Black Sea ◽

Russian Revolution ◽

The Black Sea ◽

North East ◽

The First World War ◽

The Family ◽

Northern Shore ◽

The Russian Empire ◽

The Village ◽

First World

Hans Lissmann overcame extraordinary difficulties to become one of the pioneers of experiments on animal locomotion and the discoverer of the electric sense of fishes. The Russian Empire He was born on 30 April 1909 at Nikolayev, a Black Sea port near Odessa. Most of what we know of his early life comes from two typewritten memoirs, written in 1944 when he was interned. He was the younger of the two sons of German parents, Robert Lissmann, an exporter of grain, and his wife Ebba. A photograph taken in 1913 or 1914 shows a prosperous family formally posed with the boys dressed immaculately and impractically, entirely in white. Until Hans was five the family lived in Nikolayev and in Novorossiysk, another port on the northern shore of the Black Sea. He spoke Russian with his parents and French with his grandparents. Then, after the outbreak of the First World War in 1914, the family was sent to Kargala, a village near Orenburg on the edge of the Urals, 1100 miles north-east of Nikolayev. There they were interned as aliens among a population of Tartars, Bashkirs and Kirghis. Hans learned some Tartar, and was also taught German. Drawings that he made there show a village of log buildings inhabited by men in turbans, and a rider on a Bactrian camel. Their mother taught the boys arithmetic and languages, and arranged for them to be introduced to biology by an interned zoologist and a botanist who took them into the surrounding countryside on summer afternoons. She supported the family by teaching in the village school when her husband was arrested and taken away for several months. The Russian Revolution came, and Kargala was captured and recaptured several times by the Reds and Whites.

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The Baron de Baye's Antiquities from North-east Russia and Siberia

The Antiquaries Journal ◽

10.1017/s0003581500004601 ◽

1923 ◽

Vol 3 (1) ◽

pp. 52-60

Author(s):

Ellis H. Minns

Keyword(s):

Eighteenth Century ◽

Black Sea ◽

The Black Sea ◽

North East ◽

Black Sea Coast ◽

East Russia ◽

The Crimea ◽

Northern Russia ◽

Sea Coast ◽

West European

The archaeology of the Black Sea coast quickly attracted attention when the Russians conquered the Crimea at the end of the eighteenth century, and the Scythic barrows of the Steppes began to be carefully excavated almost as soon; but it was not till the fifties and sixties that the less imposing antiquities of northern Russia found any one to study them even among Russians. West European interest naturally came later, the pioneers were first the Finn Aspelin in the seventies and next the Baron de Baye, who about 1890 sought to throw light from the East upon the Merovingian and other Teutonic styles which were his special province.

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