scholarly journals The Origin of Hydrocarbon Gases in the Lovozero Nepheline-Syenite Massif (Kola Peninsula, NW Russia), as Revealed from He and Ar Isotope Evidence

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 830
Author(s):  
Valentin Nivin
Keyword(s):  
Practical Interest ◽  
Fluid Phase ◽  
Lovozero Massif ◽  
Hydrocarbon Gases ◽  
Geological Processes ◽  
Argon Isotopes ◽  
History Of ◽  
High Concentrations ◽  
Helium And Argon Isotopes ◽  
Gaseous Hydrocarbons

The occurrence of hydrocarbon gases (HCG) in unusually high concentrations for magmatic complexes, in the Lovozero and some other alkaline massifs, is of both geochemical and practical interest. The nature of these gases, despite the long history of research, remains the subject of debate. As an approach to solving this problem, we studied the coupled distribution of occluded HCG and the recognized tracers of various geological processes, such as helium and argon isotopes. The extraction of the gas components trapped in fluid micro-inclusions was carried out by the mechanical crushing of rock and mineral samples. A positive correlation was found between the 3He/4He and CH4/C2H6 ratios, whereas a negative correlation of the latter was found with the 36Ar concentration, which in turn was directly related, in varying degrees, to the content of HCG and most strongly with pentanes. Conjugacy of the processes of the heavier gaseous hydrocarbons, a loss of the deep component of the fluid phase and dilution of it with the atmogenic component was established. In the absence of a correlation between CH4 and 3He, the value of the CH4/3He ratio in the Lovozero gas substantially exceeded the estimates of it in gases of a mantle origin, and mainly corresponded to the crustal values. However, in some samples, a small fraction of mantle methane was allowed. The peculiarities of the relationships between hydrocarbon gases and the isotopes of noble gases indicate a sequential process of abiogenic generation and transformation of HCG at the magmatic and post-magmatic stages during the formation of the Lovozero massif. The obtained results confirm the usefulness of this approach in solving the origin of reduced gases in alkaline igneous systems.

Magnetite (U-Th-Sm)/He dating: analytical challenges and application

2021 ◽  
Author(s):  
Marianna Corre ◽  
Martine Lanson ◽  
Arnaud Agranier ◽  
Stephane Schwartz ◽  
Fabrice Brunet ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Subduction Zones ◽  
Major Elements ◽  
Western Alps ◽  
Planetary Science ◽  
Mantle Xenoliths ◽  
Transform Faults ◽  
Geological Processes ◽  
History Of ◽  
Geochronological Constraints

<p>Magnetite (U-Th-Sm)/He dating method has a strong geodynamic significance, since it provides geochronological constraints on serpentinization episodes, which are associated to important geological processes such as ophiolite obductions, subduction zones, transform faults and fluid circulations. Although helium content that range from 0.1 pmol/g to 20 pmol/g can routinely be measured, the application of this dating technique however is still limited due to major analytical obstacles. The dissolution of a single magnetite crystal and the measurement of the U, Th and Sm present at the ppb level in the corresponding solution, remains highly challenging, especially because of the absence of magnetite standard. In order to overcome these analytical issues, two strategies have been followed, and tested on magnetite from high-pressure rocks from the Western Alps (Schwartz et al., 2020). Firstly, we purified U, Th and Sm (removing Fe and other major elements) using ion exchange columns in order to analyze samples, using smaller dilution. Secondly, we performed in-situ analyzes by laser-ablation-ICPMS. Since no solid magnetite certified standard is yet available, we synthetized our own by precipitating magnetite nanocrystals. The first quantitative results obtained by LA-ICP-MS using this synthetic material along with international glass standards, are promising. The laser-ablation technique overcomes the analytical difficulties related to sample dissolution and purification. It thus opens the path to the dating of magnetite (and also spinels) in various ultramafic rocks such as mantle xenoliths or serpentinized peridotites in ophiolites.</p><p>Schwartz S., Gautheron C., Ketcham R.A., Brunet F., Corre M., Agranier A., Pinna-Jamme R., Haurine F., Monvoin G., Riel N., 2020, Unraveling the exhumation history of high-press ure ophiolites using magnetite (U-Th-Sm)/He thermochronometry. Earth and Planetary Science Letters 543 (2020) 116359.</p>

A SHORT HISTORY OF PALEONTOLOGY IN TURKEY, PART I: FROM THE NINETEENTH CENTURY TO THE COLLAPSE OF OTTOMAN TURKEY

2021 ◽  
Vol 40 (1) ◽  
pp. 158-201
Author(s):  
VOLKAN SARIGÜL
Keyword(s):  
Nineteenth Century ◽  
Petroleum Exploration ◽  
Stratigraphic Analysis ◽  
Coal Beds ◽  
Geological Processes ◽  
Natural History Collection ◽  
History Of ◽  
Ottoman Turkey ◽  
The Rich ◽  
Military Engineering

ABSTRACT Modern paleontology in Turkey appeared in the early nineteenth century, together with the first modern geological studies. The fossils collected in these studies were initially used to establish biostratigraphy and to make the first geological maps of the country. Paleontologists were involved in these studies from the beginning; the earliest identifications of new animal and plant taxa from Turkey occurred in the same century along with the detailed descriptions of the rich and diverse Turkish fossil record. Aside from the academic studies, some paleontologists also took part in the economic side by contributing to stratigraphic analysis of coal beds or participating in petroleum exploration. All these pioneering works on the geology and paleontology of Turkey were done by foreigners; however, the outcomes of this newly introduced science were quickly appreciated by Ottoman Turkey. During the middle of the nineteenth century, the first text mentioning geological processes was written by the head scholar of the Imperial School of Military Engineering, while the first geology classes began to be taught under the Imperial Medical School in Istanbul, in which the first natural history collection was also established. Unfortunately, not a single original study in paleontology was produced by Ottoman citizens, with the notable exception of an Austrian immigrant of Hungarian descent, possibly because of a lack of a real interest in earth sciences.

Meiobenthos as indicator of gaseous hydrocarbons reservoirs existing under the seabed of the Black Sea

2021 ◽  
Author(s):  
Valentina Yanko ◽  
Anna Kravchuk ◽  
Irina Kulakova ◽  
Tatiana Kondariuk
Keyword(s):  
Black Sea ◽  
Abiotic Factors ◽  
Taxonomic Composition ◽  
The Black Sea ◽  
Northwestern Part ◽  
Hydrocarbon Gases ◽  
The Sustainable Development ◽  
Dual Analysis ◽  
Gaseous Hydrocarbons ◽  
Physical And Chemical

<p>This <span>presentation</span> represents a case study that reviews research into the relationship between meiobenthos distribution and concentrations of hydrocarbon gases (HG), primarily methane, in the sediments of the northwestern part of the Black Sea, including gases released by mud volcanoes and gas seeps. Evidence forming the basis of this research comes from meiobenthos here represented by 29 species of benthic foraminifers, 7 species of ostracods, and 44 species of nematodes. The potential use of these meiobenthic organisms as indicators of gaseous hydrocarbons reservoirs existing under the seabed is evaluated according to two linked axes, namely the dual analysis of abiotic factors (physical and chemical parameters of the water column, gasmetrical, geochemical, lithological, and mineralogical properties of the sediments) and biotic characteristics (quantitative and taxonomic composition of foraminifers, nematodes, and ostracods). Studies of this kind have been directed toward developing interdisciplinary methods to improve the search for HG accumulations, especially methane, under the seabed. Development of such methods might have substantial socio-economic importance for the economy of Ukraine as well as that of other Black Sea countries, and such methods might also contribute to the sustainable development of Black Sea ecosystems.</p>

Magmatic-Hydrothermal Fluids

Elements ◽  
2020 ◽  
Vol 16 (6) ◽  
pp. 401-406 ◽  
Author(s):  
Andreas Audétat ◽  
Marie Edmonds
Keyword(s):  
Metal Content ◽  
Fluid Phase ◽  
Volcanic Eruptions ◽  
Hydrothermal Systems ◽  
Ore Deposits ◽  
Hydrothermal Fluids ◽  
Geological Processes ◽  
Mineral Growth ◽  
Fluid Saturation ◽  
Fluid Phase Equilibria

Magmatic-hydrothermal fluids play a key role in a variety of geological processes, including volcanic eruptions and the formation of ore deposits whose metal content is derived from magmas and transported to the site of ore deposition by means of hydrothermal fluids. Here, we explain the causes and consequences of fluid saturation in magmas, the corresponding fluid-phase equilibria, and the behavior of metals and ligands during the transition from magma to an exsolved hydrothermal fluid. Much of what we know about magmatic-hydrothermal systems stems from the study of fluid inclusions, which are minute droplets of fluids trapped within minerals during mineral growth.

In the Air

2020 ◽  
pp. 35-75
Author(s):  
George Oppitz-Trotman
Keyword(s):  
Knowledge Transfer ◽  
Early Modern ◽  
Christopher Marlowe ◽  
Practical Interest ◽  
Literary Interpretation ◽  
Early Modern Europe ◽  
Frankfurt Am Main ◽  
History Of ◽  
Moral Lesson ◽  
Unique Ability

Few plays insist more adamantly upon a connection between travel and moral loss than The Tragical History of Doctor Faustus. Here it is argued that the play written by Christopher Marlowe was performed by the English Comedians in Frankfurt-am-Main as early as Autumn 1592, and that it remained in their repertoire throughout the 1590s—before an English play-text was published (in 1604), indeed before its first recorded English performance (in 1594). The play’s unique ability to reconcile a wide array of comic materials to a powerful moral lesson recommended it to itinerant theatre groups. Yet the tonal unevenness of the extant English editions has been an evergreen concern for editors and critics. Having established that the play was performed abroad and thus adapted for many different audiences and scenarios, this chapter suggests that the confusing middle of the extant text(s) represents the modularity of its structure in the 1590s. Marlowe’s ultimate source had been published in Frankfurt in 1587, and merchants at the city’s fair had practical interest and expertise in contracts of all kinds. The performance of the English play there raises many exciting new questions not only of literary interpretation but also of knowledge transfer in early modern Europe.

THE CONCENTRATION AND ACCUMULATION OF LIPIDS IN THE TUMOR COMPONENT OF A TUMOR–HOST ORGANISM, WALKER CARCINOMA 256 IN ALBINO RATS

1952 ◽  
Vol 30 (3) ◽  
pp. 163-172
Author(s):  
Eldon M. Boyd ◽  
H. D. McEwen
Keyword(s):  
Life History ◽  
Lipid Analysis ◽  
Albino Rats ◽  
Host Organism ◽  
History Of ◽  
Marked Accumulation ◽  
High Concentrations ◽  
Walker Carcinoma ◽  
Accumulation Of Lipids ◽  
Host Component

A study was made of the lipid concentration and accumulation in the tumor component of a tumor–host organism at progressive intervals during its growth using Walker Carcinoma 256 in albino rats. At the end of each of 7, 14, 21, and 28 days of tumor growth, and covering the entire life history of Walker Carcinoma 256, 10 tumor–rat organisms were sacrificed and appropriate sections of the tumor removed for differential lipid analysis by oxidative micromethods. The outstanding feature revealed in these studies was the maintenance, throughout its life history, of high concentrations of phospholipid, free and esterified cholesterol in Walker Carcinoma 256, and the increasing accumulation of large amounts of these lipids in the tumor component of the tumor–host organism. There was no marked accumulation of neutral fat which, in the tumor, declined to almost l/10th its initial concentration concurrently with the visible loss of storage fat in the host component. A day or two before death, the central core of the tumor appeared necrotic, its concentration of phospholipid declined and its concentration of free cholesterol rose. Otherwise, the lipid composition of the tumor was uniform throughout the cross section.

scholarly journals Helium in the Australian liquefied natural gas economy

2018 ◽  
Vol 58 (1) ◽  
pp. 209 ◽  
Author(s):  
Christopher J. Boreham ◽  
Dianne S. Edwards ◽  
Robert J. Poreda ◽  
Thomas H. Darrah ◽  
Ron Zhu ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Natural Gas ◽  
Economic Value ◽  
Industrial Process ◽  
Sedimentary Basins ◽  
Liquefied Natural Gas ◽  
Hydrocarbon Gases ◽  
Apparent Loss ◽  
Argon Isotopes ◽  
Northern Carnarvon Basin

Australia is about to become the premier global exporter of liquefied natural gas (LNG), bringing increased opportunities for helium extraction. Processing of natural gas to LNG necessitates the exclusion and disposal of non-hydrocarbon components, principally carbon dioxide and nitrogen. Minor to trace hydrogen, helium and higher noble gases in the LNG feed-in gas become concentrated with nitrogen in the non-condensable LNG tail gas. Helium is commercially extracted worldwide from this LNG tail gas. Australia has one helium plant in Darwin where gas (containing 0.1% He) from the Bayu-Undan accumulation in the Bonaparte Basin is processed for LNG and the tail gas, enriched in helium (3%), is the feedstock for helium extraction. With current and proposed LNG facilities across Australia, it is timely to determine whether the development of other accumulations offers similar potential. Geoscience Australia has obtained helium contents in ~800 Australian natural gases covering all hydrocarbon-producing sedimentary basins. Additionally, the origin of helium has been investigated using the integration of helium, neon and argon isotopes, as well as the stable carbon (13C/12C) isotopes of carbon dioxide and hydrocarbon gases and isotopes (15N/14N) of nitrogen. With no apparent loss of helium and nitrogen throughout the LNG industrial process, together with the estimated remaining resources of gas accumulations, a helium volumetric seriatim results in the Greater Sunrise (Bonaparte Basin) > Ichthys (Browse Basin) > Goodwyn–North Rankin (Northern Carnarvon Basin) accumulations having considerably more untapped economic value in helium extraction than the commercial Bayu-Undan LNG development.

Albumin absorption by canine bronchial epithelium

1989 ◽  
Vol 66 (6) ◽  
pp. 2772-2777 ◽  
Author(s):  
L. G. Johnson ◽  
P. W. Cheng ◽  
R. C. Boucher
Keyword(s):  
Gel Filtration ◽  
Fluid Phase ◽  
Bronchial Epithelium ◽  
Bathing Solution ◽  
Michaelis Constant ◽  
Airway Epithelia ◽  
Ussing Chambers ◽  
Bronchial Epithelia ◽  
Surface Liquid ◽  
High Concentrations

Albumin concentrations in airway surface liquid are low compared with plasma. To investigate the mechanisms that generate albumin gradients across airway epithelia, we have investigated whether active albumin absorption is a feature of bronchial epithelia. Freshly excised canine bronchi were mounted in Ussing chambers and short-circuited. Permeability coefficients of 14C-labeled canine albumin (Palb) were measured in the mucosal-to-submucosal (M----S) and submucosal-to-mucosal (S----M) directions in conductance-matched tissues. Mean steady-state values for Palb in the absorptive (M----S) direction (5.97 +/- 1.89 x 10(-7) cm/s) were significantly greater than rates in the S----M direction (1.09 +/- 0.41 x 10(-7) cm/s). Simultaneous measurements detected no asymmetry of transport of the fluid phase marker [3H]inulin. Gel filtration chromatography demonstrated that the majority of the radiolabel released into the submucosal bathing solution represented albumin fragments. Albumin fragments per se were not transported because no asymmetries in permeabilities of albumin fragments isolated from spontaneous degradation of tracer were detected. Decreasing the temperature of the bathing solution from 37 to 4 degrees C completely inhibited net albumin absorption. [14C]albumin transport was saturated by addition of high concentrations of unlabeled albumin (estimated Michaelis constant = 1.6 x 10(-3) M). These results demonstrate that albumin is absorbed by a low-affinity process that may contribute to the maintenance of low albumin concentrations in secretions.

β2-Glycoprotein I: Target antigen for ‘antiphospholipid’ antibodies. Immunological and molecular aspects

Lupus ◽  
1998 ◽  
Vol 7 (2_suppl) ◽  
pp. 5-9 ◽  
Author(s):  
Y Sheng ◽  
DA Kandiah ◽  
SA Krilis
Keyword(s):  
Antiphospholipid Syndrome ◽  
Antiphospholipid Antibodies ◽  
Fluid Phase ◽  
Target Antigen ◽  
Phospholipid Membranes ◽  
Anionic Phospholipid ◽  
Glycoprotein I ◽  
High Concentrations ◽  
Molecular Aspects ◽  
Anionic Phospholipid Membranes

It has become clear that β2-glycoprotein I (β2GPI) is the most common and best-characterised antigenic target for ‘antiphospholipid’ (aPL) autoantibodies. These antibodies preferentially bind β2GPI that has been immobilised on anionic phospholipid membranes or certain synthetic surfaces. These surfaces appear to act by increasing antigen density to allow binding of intrinsically low-affinity anti-β2GPI autoantibodies. Binding of β2GPI in fluid phase is weak and requires high concentrations of β2GPI. Our understanding of the pathophysiology of the ‘Antiphospholipid’ Syndrome (APS) has increased exponentially with the number of studies into the interactions of aPL antibodies and β2GPI.

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