Papers by Anastassia Borisova
Izvestiya, Atmospheric and Oceanic Physics
The morphostructural characteristics of the main taxa of southern Indian Ocean, such as the Del C... more The morphostructural characteristics of the main taxa of southern Indian Ocean, such as the Del Cano-Crozet, Conrad, and Kerguelen plateaus, are given based on structural-tectonic analysis. A depth map of the acoustic basement of the eastern part of the Afro-Antarctic megadepression is first built using the digitized NGDS database on the thickness of the sedimentary cover of the Indian Ocean, which is available on the Internet. A critical analysis of deep seismic sounding (DSS) data on the Kerguelen plateu hs been performed. A geochemical analysis of more than 100 samples of basalts, acidic rocks, and rocks of sedimentary origin, collected on the islands of the Kerguelen archipelago and raised by dredging and deep-sea drilling from the Kerguelen and Conrad plateaus, is carried out. The study has shown that the plateaus resemble the Madagascar Ridge in terms of morphostructure and a number of other features. It is concluded that these flat-topped horst massifs were the part of the "structural bridge" that connected Madagascar and the eastern part of mainland Antarctica no later than the Paleogene. A proposed alternative version of the geological interpretation of the deep seismic data states that the plateau has a relatively homogeneous structure along the strike, including a thick (at least 15-km) layer of continental crust. An analysis of the depth map of the acoustic basement made it possible to identify the depocenters of the relatively isolated Enderby, Shackleton and Labuan basins framing the Kerguelen Plateau on the southern side. The paragenetic connections of the Kerguelen Plateau with the basins indicate that the isolation of the Kerguelen Plateau from East Antarctica and the formation of the modern structure of the region began in the Late Cretaceous and ended with the last phase of tectonic activation in the Late Miocene-Pliocene. The results of geochemical analysis show that the geochemical and petrological anomalies of the plateau and islands are associated with the crust, and not with the mantle contamination, as well as with the continental nature of the Kerguelen Plateau.
Goldschmidt2021 abstracts, 2021
Goldschmidt2021 abstracts, 2021
Eos, 2021
Laboratory experiments serendipitously revealed a rock-forming process that might explain how the... more Laboratory experiments serendipitously revealed a rock-forming process that might explain how the first continental crust formed on Earth—and possibly on Mars.
Precambrian Research, 2019
Granophyric rocks on Earth are enigmatic and may be investigated by detailed sampling, empirical ... more Granophyric rocks on Earth are enigmatic and may be investigated by detailed sampling, empirical method and modeling. This work presents recent results on the 2445 ± 5 Ma Kivakka layered mafic-ultramafic intrusion in Northern Karelia, Russia, in particular, leucocratic lenses in the upper cumulative zone. Based on detailed sampling, mineralogical and petrologic investigation coupled with COMAGMAT petrologic modeling, the following sequence of the fractional crystallization of the main rock-forming minerals is established: olivine, olivine + orthopyroxene, orthopyroxene, orthopyroxene + plagioclase, orthopyroxene + plagioclase + augite, plagioclase + augite + pigeonite. We propose a petrologic model of the leucocratic granophyric rock origin from the residual melt produced at late stages of evolution of the Kivakka massif via closed-system fractional crystallization and convective mixing of magma in the chamber. Comparison of the granophyric rocks with lunar KREEP and granophyric rocks of other terrestrial massifs is performed based on the major and trace element composition of the rocks and minerals. We believe that the Proterozoic granophyric rock origin on Earth may be comparable to the origin of the lunar KREEP rocks due to high differentiation degree of the parental basaltic magma.
arXiv: Materials Science, 2020
Chromite is a key magmatic mineral frequently used as petrogenetic indicator of physico-chemical ... more Chromite is a key magmatic mineral frequently used as petrogenetic indicator of physico-chemical conditions of mafic magma crystallization. In this work, magnesiochromite and chromite solubility in a natural basalt and an iron-free haplobasalt was investigated at 1440°C and atmospheric pressure under controlled CO-CO2 gas mixtures corresponding to the range two log units below to two log units above the fayalite-magnetite-quartz buffer. The source of chromium was either natural chromite or synthetic Cr2O3, the latter reacting with the basaltic liquids to form a magnesiochromite. The highest concentrations of Cr in haplobasaltic melts are found in equilibrium with magnesiochromite, depending on redox conditions. In detail, at low fO2, liquids have high Cr contents, but the variation of log [Cr, ppm] is not a linear function of log fO2. Using our new data and data from the literature a model for Cr concentrations at chromite/magnesiochromite saturation in silicate melts has been devel...
Izvestiya, Atmospheric and Oceanic Physics
Izvestiya, Atmospheric and Oceanic Physics, 2020
A comprehensive analysis of extensive primary (morphological, geological, geophysical, and geoche... more A comprehensive analysis of extensive primary (morphological, geological, geophysical, and geochemical—including deep-sea drilling) data provides deep insight into the morphostructure, geology, and evolution of the West Australian Ridge (WAR) (or Broken Ridge), which unambiguously testify to its continental origin. The northeastern slope was distinguished additionally to two previously known main morphostructural elements of the ridge: the northern and southern slopes. It is inclined towards the Naturaliste abyssal plain and structurally forms its northwestern framing. It has been established that the morphology of the slopes is caused by the peculiarities of the tectonic development of the adjacent basins. It is determined that the sedimentary cover of the central part of the northern slope contains a lower (basal) seismoacoustic complex, which has not been exposed by deep-sea drilling and formed no later than the Early Cretaceous. The final subsidence of individual fragments of the ridge and the formation of its present-day morphostructure, as well as the structural-tectonic rearrangement of the adjacent areas, occurred at the youngest phase of tectonic activation in the Late Miocene–Pliocene.
Minerals
The solubility of Pt in CO-CO2 fluid was studied experimentally at P = 50–200 MPa and T = 950 °C.... more The solubility of Pt in CO-CO2 fluid was studied experimentally at P = 50–200 MPa and T = 950 °C. A mixture of MgC2O4 and MgCO3 was used as a source of the fluid. Upon the reaction of the Pt capsule walls and the fluid, a carbonyl of platinum is formed. The use of the high-temperature quartz ceramics as a fluid trap avoids the effect of mechanical contamination with Pt from the eroded capsule walls. The total content of platinum in the porous fluid traps was measured by the Electrothermal Atomic Absorption (ET-AAS) method. In some experiments, the local analysis of traps was carried out by the Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) method. The composition of fluid in bubbles captured in an albite glass trap was studied by micro-Raman spectroscopy. On the capsule walls and MgO, Pt “whiskers” of submicron diameter were observed, which were formed as a product of carbonyl decomposition during quenching. About 5–15% of carbonyl withstands quenching resul...
Mineralogy and Petrology
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
European Journal of Mineralogy, 2021
Recent advances in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) open n... more Recent advances in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) open new perspectives for quantification of trace metals and metalloids in mineral-hosted fluid inclusions and glasshosted gas bubbles. This work is devoted to a new method applied to quantify element concentrations (at partsper-million and weight percent levels) in natural and synthetic fluid inclusions and gas bubbles by using only an external calibrator in cases where internal standardization is unavailable. For example, this method can be applied to calculate element (metal and metalloid) concentrations in carbonic (C-O-H) fluid inclusions and bubbles. The method is devoted to measuring incompatible (with the host mineral and glass) trace elements originally dissolved into the trapped fluid. The method requires precise estimation of the fluid density, the inclusion/bubble volume or average radius, and measurement of the laser ablation crater radius by independent microanalytical techniques as well as accurate data on the concentration of major/minor elements compatible with the host mineral (or host glass). This method, applicable for analyses of hydrous carbonic fluid inclusions and gas bubbles hosted in silicate minerals and glasses, relies on the absence of a matrix effect between fluid, host mineral and daughter phases (silicate, oxide or sulfide) and the external calibrator (e.g., reference silicate glasses) during the LA-ICP-MS analysis, an assumption validated by the use of femtosecond lasers.
Geology, 2021
Hadean zircons, from the Jack Hills (Western Australia) and other localities, are currently the o... more Hadean zircons, from the Jack Hills (Western Australia) and other localities, are currently the only window into the earliest terrestrial felsic crust, the formation of which remains enigmatic. Based upon new experimental results, generation of such early crust has been hypothesized to involve the partial melting of hydrated peridotite interacting with basaltic melt at low pressure (<10 km), but it has yet to be demonstrated that such liquids can indeed crystallize zircons comparable to Jack Hills zircon. We used thermodynamic and geochemical modeling to test this hypothesis. The predicted zircon saturation temperatures of <750 °C, together with the model zircon Th, U, Nb, Hf, Y, and rare earth element (REE) contents at 700 °C, δ18OVSMOW (Vienna standard mean ocean water) signatures, and co-crystallizing mineral assemblage were compared to those of the Jack Hills zircon. This comparison was favorable with respect to crystallization temperature, most trace-element contents, and...
Thermodynamics of Geothermal Fluids, 2013
arXiv: Geophysics, 2020
To constrain a contribution of deep carbonated mantle, to fractionation of Hf relative to rare ea... more To constrain a contribution of deep carbonated mantle, to fractionation of Hf relative to rare earth elements (REE) in volcanic series, we examine available high-quality data on major, trace element and Nd-Hf isotope compositions of primitive lavas and glasses erupted during preshield, postshield and mostly rejuvenated stage of the Hawaiian hot spot (Pacific Ocean). Strong variations of Hf/Sm, Zr/Sm, Ti/Eu, K/Th, Nb/Th, La/K and Ba/K in the lavas are not features of the melt equilibration with residual amphibole or phlogopite, and cannot be due to variable degrees of batch or dynamic melting of uncarbonated lherzolite source. Enrichment in REE, Th and Ba relative to K, Hf, Zr, Ti and Nb together and low Si, high Na, K and Ca contents in the Hawaiian lavas are compositional features of carbonated mantle lithospheric to asthenospheric peridotite source affected by carbonatite metasomatism. In contrast, major and trace element signatures of most primitive preshield- and postshield-stag...
Frontiers in Earth Science, 2021
Editorial on the Research Topic Magma-Rock and Magma-Mush Interactions as Fundamental Processes o... more Editorial on the Research Topic Magma-Rock and Magma-Mush Interactions as Fundamental Processes of Magmatic Differentiation Virtually all terrestrial magmas, in all geodynamic settings, interact, sometimes profoundly, with surrounding rocks during their generation, residence at depth, and ascent through the asthenosphere and lithosphere. This results in inevitable interactions (exchanges of heat and matter) described as magma/melt-rock or magma/melt-mush interactions. The major processes that happen when silicate magma is in contact with surrounding rocks were first defined in the pioneering studies of Bowen (1928) who identified two types of reactions: partial melting of the wall rocks and mineral dissolution in silicate melt. These reactions, which are ubiquitous during magma evolution, are commonly referred to as 'assimilation' (DePaolo, 1981), but may more broadly be called open-system processes. Assimilation, magma mixing, degassing, magma-rock and fluid-rock interactions control magma and fluid composition, metal and volatile contents, and magma physical-chemical properties and mobility. Consequently, the interactions influence volcanic activity, ore deposit formation, growth of the crust, and terrestrial climate. However, the degree, rates, and mechanisms of these reactions are poorly quantified owing to a lack of natural and experimental data and predictive models. This research volume 'Magma-Rock and Magma-Mush Interactions as Fundamental Processes of Magmatic Differentiation' is devoted to documenting recent achievements in the fields of kinetics and thermodynamics as well as the petrologic and geochemical consequences of magma-rock, meltrock, and melt-mush interactions. New observations of natural systems and laboratory experimental approaches that address how magma, melt, mush and rock interact are represented by seven articles (Baudouin and Parat; Borisova et al.; Boulanger et al.; Pistone et al.; Sanfilippo et al.; Tassara et al.; Borisova et al.). Examples of these types of interactions include mantle metasomatism (Baudouin and Parat), mineral-melt reaction in the planetary ultramafic protocrust (Borisova et al.) and in the terrestrial mantle (Borisova et al.; Sanfilippo et al.), melt-mush interaction in the crust (Pistone et al.), and thermal and chemical modification of preexisting mushy magma by intrusion of high specific enthalpy (enthalpy per unit mass) magma (Boulanger et al.). The melt-rock interactions also affect the redox state of percolating melts that may become enriched in ore-forming metals (Tassara et al.).
arXiv: Earth and Planetary Astrophysics, 2020
Current theories suggest that on Earth and, possibly, on other terrestrial planets early in their... more Current theories suggest that on Earth and, possibly, on other terrestrial planets early in their history, the first continental crust may has been produced by direct melting of hydrated peridotite. However, the conditions, mechanisms and necessary ingredients of such production remain elusive. To fill this gap, we have conducted experiments of serpentinite melting in the presence of variable proportions of basaltic melt, at typical conditions of the shallow lithosphere and asthenosphere. These experiments revealed formation of silica-rich liquids, which are similar to tonalite-trondhjemite-granodiorite magmas (TTG) identified in modern terrestrial oceanic mantle settings. Our results suggest a new mechanism of aqueous fluid-assisted partial melting of peridotite that may have operated on the early Earth and Mars just after the solidification of an ultramafic-mafic magma ocean, leading to the formation of the first embryos of continental crust. The proposed mechanism of the continen...
The EGU General Assembly, 2011
Syn-eruptive monitoring of volcanic fluid, pyroclastic and aerosol phases is one of the main appr... more Syn-eruptive monitoring of volcanic fluid, pyroclastic and aerosol phases is one of the main approaches to predict explosivity and duration of a current eruptive event. To constrain the fluid source as well as the pre- and syn-eruptive evolution of fluid - magma system of the 2010 Merapi volcano (Indonesia), we investigated the chemistry of pyroclasts and ashes collected on northern and western slopes on 9th November 2010 (originated from 5th to 6th November 2010 ash falls). The samples have been polished and investigated using a scanning electron microscopes (coupled with the automatic analyzer of particles by the program "Esprit" working in the module "Feature" in GET). Major element compositions were determined by electron microprobe analysis using two CAMECA SX50 equipped with SAMX automation and wavelength-dispersive spectrometer (WDS) in GET and ISTO. The first data demonstrates common presence of quartz (0.2 - 0.3 %), plagioclase (51 - 60%), alkaline felds...
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Papers by Anastassia Borisova