| 1. |
- A. Marques, Ana F., et al.
(author)
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The Seven Sisters Hydrothermal System : First Record of Shallow Hybrid Mineralization Hosted in Mafic Volcaniclasts on the Arctic Mid-Ocean Ridge
- 2020
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In: Minerals. - : MDPI AG. - 2075-163X.
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Other publication (other academic/artistic)abstract
- We document the discovery of an active, shallow, seafloor hydrothermal system (known as the Seven Sisters Vent Field) hosted in mafic volcaniclasts at a mid-ocean ridge setting. The vent field is located at the southern part of the Arctic mid-ocean ridge where it lies on top of a flat-topped volcano at ~130 m depth. Up to 200 deg C phase-separating fluids vent from summit depressions in the volcano, and from pinnacle-like edifices on top of large hydrothermal mounds. The hydrothermal mineralization at Seven Sisters manifests as a replacement of mafic volcaniclasts, as direct intraclast precipitation from the hydrothermal fluid, and as elemental sulfur deposition within orifices. Barite is ubiquitous, and is sequentially replaced by pyrite, which is the first sulfide to form, followed by Zn-Cu-Pb-Ag bearing sulfides, sulfosalts, and silica. The mineralized rocks at Seven Sisters contain highly anomalous concentrations of ‘epithermal suite’ elements such as Tl, As, Sb and Hg, with secondary alteration assemblages including silica and dickite. Vent fluids have a pH of ~5 and are Ba and metal depleted. Relatively high dissolved Si (~7.6 mmol/L Si) combined with low (0.2–0.4) Fe/Mn suggest high-temperature reactions at ~150 bar. A delta-13C value of -5.4 permil in CO2 dominated fluids denotes magmatic degassing from a relatively undegassed reservoir. Furthermore, low CH4 and H2 (<0.026 mmol/kg and <0.009 mmol/kg, respectively) and 3He/4He of ~8.3 R/Racorr support a MORB-like, sediment-free fluid signature from an upper mantle source. Sulfide and secondary alteration mineralogy, fluid and gas chemistry, as well as delta-34S and 87Sr/86Sr values in barite and pyrite indicate that mineralization at Seven Sisters is sustained by the input of magmatic fluids with minimal seawater contribution. 226Ra/Ba radiometric dating of the barite suggests that this hydrothermal system has been active for at least 4670 +/- 60 yr.
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| 3. |
- Andersson, Ulf Bertil, et al.
(author)
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Emendment to the term complex in: “Guide for geological nomenclature in Sweden” (Kumpulainen 2016)
- 2022
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In: GFF. - : Taylor & Francis. - 1103-5897 .- 2000-0863. ; 144:3-4, s. 151-151
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Journal article (other academic/artistic)abstract
- Since the publication of Kumpulainen (2016), the Committeehave been alerted by the investigation and subsequent changesto the North American Stratigraphic Code concerning thelithodemic unit“complex”(Easton et al.2016; North Ameri-can Commission on Stratigraphic Nomenclature (NACSN)2017). These changes concern the introduction of the nomen-clature unit“Intrusive Complex”. In the original version(NACSN1983), as well as in the Swedish Guide for nomencla-ture (Kumpulainen2016), the unit“complex”is defined ascontaining at least two genetic classes of rocks, i.e., igneous,sedimentary, or metamorphic.
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| 6. |
- Bagriy, I.D., et al.
(author)
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H2 - Ecological source of decarbonization - The path to energy independence of Ukraine
- 2023
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Book (other academic/artistic)abstract
- The research studied the pressing problem of the fuel and energy strategy of the XXI century. For the first time, there was shown the diversity of the authors' approach to theoretical and applied problems of hydrogen energy. General issues of fundamental and applied aspects of hydrogen origin were covered. The study provides the results of scientific developments on hydrogen mapping performed within the framework of scientific and practical exploratory and geo-ecological research on more than 200 hydrocarbon objects both on land (including mining fields) and in marine water areas. Prognostic and search system criteria were substantiated, with hydrogen being used for the first time as a component of the complex of methodical solutions in the search practice. The research showed the importance of solving the problem of geo-ecological processes and accidents in mine workings and wells, connected to numerous disasters. According to numerous studies of mine massives, a set of preventive measures and criteria that prevent explosive processes was provided.The presence of a unique complex of natural components of hydrogen technology, solar and wind energy resources and fresh waters of the Danube lakes and the Danube was stated.The study emphasises the decisive role of Ukraine in the competition for primacy in scientific developments. For the first time in world practice, the implementation of global projects for the extraction and production of green and white hydrogen was substantiated.The technology was tested on numerous hydrocarbon deposits, water resources and mine workings and therefore has all the prospects for the effective application in the search and extraction of hydrogen. This monograph can be useful and informative for specialists in the fields of oil and gas geology, general and regional geology, hydrology, environmental protection, as well as for the students and postgraduate students of fuel and energy, oil and gas geological and hydrological areas, as well as for domestic and foreign investors.
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| 8. |
- Bergsten, Johannes, 1975-, et al.
(author)
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Coleoptera: Dytiscidae, diving beetles, tsikovoka
- 2022. - 1
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In: The new natural history of Madagascar. - Princeton : Princeton University Press. - 9780691222622 ; , s. 1024-1034
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Book chapter (other academic/artistic)
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| 9. |
- Bergsten, Johannes, 1975-
(author)
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Coleoptera: Haliplidae, crawling water beetles
- 2022. - 1
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In: The new natural history of Madagascar. - Princeton : Princeton University Press. - 9780691222622 ; , s. 1041-1043
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Book chapter (other academic/artistic)
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| 10. |
- Bergsten, Johannes, 1975-
(author)
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Coleoptera: Hydroscaphidae, skiff beetles
- 2022. - 1
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In: The new natural history of Madagascar. - Princeton : Princeton University Press. - 9780691222622 ; , s. 1050-1051
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Book chapter (other academic/artistic)
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