Picroilmenite in Kimberlites and Titanomagnetites of the Yakutian Diamond-Bearing Province: Magnetic and Mineralogical Analysis: Experiment, Theory, Applied Significance

This book examines picroilmenites and their ferromagnetic behavior in the kimberlites from the Yakut diamondiferous province. Picroilmenites are minerals used to identify the location of diamonds. The author shows a solid interpretation of the magnetic-mineralogical analysis of ferromagnetic minerals based on a large number of experimental data and modeling of the magnetic state. He also presents the problems of the variability of the composition of picroilmenites from various kimberlite pipes. Furthermore, this book proposes a method to estimate the distribution of the decay structures dimensions, according to the thermomagnetic analysis and coercive spectra of titanomagnetites with the magnetite-ulvospinel decomposition structures. This book will be useful for students and researchers working in the field of rock magnetism, as well as geologists and geophysicists.9

Metallic Iron in Basalts of the Malyi Yenisei Lava River: Results of Thermomagnetic Study

This paper shows that the mineral composition of dolerites affects their specific paramagnetic susceptibility. Two methods for calculating the specific paramagnetic susceptibility were proposed: one used the thermomagnetic analysis (TMA) curve and the other the Mi(B) curve. There was no significant difference between the results obtained with these two approaches. Application of the proposed methods to dolerite core samples showed that specific paramagnetic susceptibility can be used as the basis for correlation of sills. The composition of titanomagnetites in dolerites can be used as an accessory parameter.461-46

MINERAL COMPOSITION OF SABAKTY LAKE SEDIMENTS

In this study, we present lithology, mineralogy and scanning electron microscopy observations along a 294 cm sediment profile of the Lake Sabakty, with the objectives of understanding the geochemical processes and improving the paleohydrological and paleoecological information during the late Pleistocene and Holocene of the South Ural.23-2

Lacustrine sediments variability on the base of magnetic properties of lake Kandrykul

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Holocene paleoclimate history of Lake Bannoe (South Ural), from magnetic, geochemical investigation, and grain‐size characteristics

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Complex investigation of Lake Bannoe sediments (South Ural, Russia)

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Archaeomagnetic investigations in Bolgar (Tatarstan)

The objective of this study is to provide a well-dated point for a future palaeosecular variation (PSV) reference curve for western Russia. For this purpose archaeomagnetic and magnetic property analyses were carried out on a pottery kiln unearthed at the UNESCO World Heritage site of ancient Bolgar, having a rather precise age dating. The archaeological context provided an age between 1340 and 1360 C.E. The characteristic remanence vector was determined through alternating field demagnetisation and Thellier-Thellier palaeointensity experiments. Some innovations were introduced regarding palaeointensity. The check testing the equality of blocking and unblocking temperature was redefined. This allowed waiving the commonly used additional zero-field cooling steps during the Thellier-Thellier experiment. Another innovation concerns the calculation of archaeointensity at structure level. A Bayesian approach was introduced for averaging individual specimen archaeointensities using a prior probability distribution of unknown uncertainties. Next, an additional prior probability distribution was used to correct for cooling rate effects. This resulted in a lower uncertainty compared to common practice and in eluding time consuming cooling rate experiments. The complex magnetic mineralogy consists of maghaemite, multi-domain haematite and Al-substituted haematite. Some samples contained also some non-stoichiometric magnetite. The magnetic mineralogy was determined through hysteresis loops, backfield and remanence decay curves, measurements of the frequency dependence of magnetic susceptibility and through low temperature magnetisation curves. Accompanying hightemperature thermomagnetic analyses revealed an excellent thermo-chemical stability of the studied specimens. Directions obtained from alternating field demagnetisation and those extracted from archaeointensity experiments are congruent and have low uncertainties. The obtained archaeomagnetic results are fairly in agreement with global geomagnetic field models and contemporary PSV data of the wider area. The geomagnetic field vector obtained for ancient Bolgar is of high quality, deserving thus its inclusion in a future PSV reference curve for European Russia.255-29

Deposition rate effect on microstructure and perpendicular magnetic anisotropy of iron films prepared by ion-beam-assisted deposition

Thin films of iron with different thickness (⁓40-300 nm) were deposited on quartz and silicon substrates by using ion beam assisted deposition (IBAD) technique. The influence of film thickness and deposition rate on microstructure, magnetic phase composition and perpendicular magnetic anisotropy (PMA) of iron films were studied by electron microscopy, X-ray diffraction, Mössbauer spectroscopy, vibrating-sample magnetometry and differential thermomagnetic analysis. Shown, that phase composition and magnetic properties of films depend substantially on the deposition rate, and, in fact, don't depend on both film thickness and the type of substrate. The strong PMA is observed in iron films formed at low (~3 nm/min) and medium (~10 nm/min) deposition rates only. The microstructure is characterized by the presence of nanocrystalline grains of α-Fe phase, as well as a significant fraction of disordered iron phase and nonmagnetic oxide phase of FeO (up to 20%). The FeO phase occurs due to the reaction of iron atoms with the residual atmosphere of the vacuum chamber. Moreover, significant positive deformation (about 3%) of crystal lattice of α-Fe grains was observed. The effect of deposition rate on the crystallinity, phase composition and PMA in thin iron films we associate with the features of the IBAD process.108860-1-108860-