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The end-Triassic extinction event (∼ 201.5 Ma) is one of the five major mass extinction events in Earth's history, however, considerable discussion continues on the exact causes and timing of the event. This is because, whilst certain geochemical data on T-J sections appears to be largely comparable globally, with for example a significant (up to 6‰) negative carbon-isotope (δ13C) excursion at the extinction horizon, more often than not other geochemical variations are neither uniform nor fully consistent between sections. Critical to this discussion is that the majority of the studied sections containing the end-Triassic extinction event are limited to shallow marine or terrestrial sections, which are prone to discontinuities and hiatuses. In this study, we present carbon isotopes (δ13Ccarb), total organic carbon (TOC), major and trace, mercury (Hg) and highly siderophile elements (HSE), osmium-isotope compositions and paleomagnetic data of a relatively less studied deep-marine T-J succession in the Budva Basin, Čanj, Montenegro. At Čanj, deep-marine Triassic limestones are abruptly interrupted by a ∼ 6 cm finely laminated clay layer, before transitioning to more argillaceous Jurassic red beds. The clay layer is interpreted to represent the end-Triassic extinction interval and is characterized by a negative carbon isotope excursion, relative heavy rare earth element (HREE) enrichment, Hg increase, HSE enrichment and a sharp shift to unradiogenic osmium-isotopic ratios. This establishes the Čanj section as a unique and well-preserved outcrop that exquisitely encapsulates the end-Triassic extinction in the Tethyan marine realm. The distinct geochemical markers recorded at Čanj are consistent with the Central Atlantic Magmatic Province as the main driver behind the end-Triassic extinction.

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 high-temperature 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.

This article belongs to the Special Issue Magnetic Nanoparticles as High-Frequency Nano-Heater., The scientific community has made great efforts in advancing magnetic hyperthermia for the last two decades after going through a sizeable research lapse from its establishment. All the progress made in various topics ranging from nanoparticle synthesis to biocompatibilization and in vivo testing have been seeking to push the forefront towards some new clinical trials. As many, they did not go at the expected pace. Today, fruitful international cooperation and the wisdom gain after a careful analysis of the lessons learned from seminal clinical trials allow us to have a future with better guarantees for a more definitive takeoff of this genuine nanotherapy against cancer. Deliberately giving prominence to a number of critical aspects, this opinion review offers a blend of state-of-the-art hints and glimpses into the future of the therapy, considering the expected evolution of science and technology behind magnetic hyperthermia., This work was supported by the NoCanTher project, which has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 685795. The authors acknowledge support from the COST Association through the COST actions “RADIOMAG” (TD1402) and “MyWAVE” (CA17115). D.O., A.S.-O. and I.R.-R. acknowledge financial support from the Community of Madrid under Contracts No. PEJD-2017-PRE/IND-3663 and PEJ-2018-AI/IND-11069, from the Spanish Ministry of Science through the Ramón y Cajal grant RYC2018-025253-I and Research Networks RED2018-102626-T, as well as the Ministry of Economy and Competitiveness through the grants MAT2017-85617-R, MAT2017-88148R and the “Severo Ochoa” Program for Centers of Excellence in R&D (SEV-2016-0686). M.B. and N.T.K.T. would like to thank EPSRC for funding (grant EP/K038656/1 and EP/M015157/1) and AOARD (FA2386-17-1-4042) award. This work was additionally supported by the EMPIR program co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation program, grant no. 16NRM04 “MagNaStand”. The work was further supported by the DFG grant CRC “Matrix in Vision” (SFB 1340/1 2018, no 372486779, project A02).

In this paper, a series of experiments are reported where ferrite nanoparticles were synthesized with different substitution percentages (5, 10, 15, or 20%) of Fe2+ by Co2+, Mn2+, or Ni2+ ions. Afterwards, the prepared nanoparticles were thermally treated between 50 and 500 &deg, C in air for 24 h in order to observe how doping influences the oxidation process induced by temperature elevation and access to O2. Nanoparticles were imaged before and after thermal treatment by transmission electron microscopy and were analyzed by X-ray diffraction, vibrating sample magnetometry, and M&ouml, ssbauer spectroscopy. Presented studies reveal that the amount and kind of doped transition metals (of replaced Fe2+) strongly affect the oxidation process of ferrite nanoparticles, which can govern the application possibility. Each transition element suppresses the oxidation process in comparison to pure Fe-oxides, with the highest impact seen with Ni2+.

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The Kleivan and Sjelset granitic complexes are two composite plutons, containing both orthopyroxene and biotite (± hornblende) facies, emplaced in the Sveconorwegian (Grenvillian) high-grade basement of SW Norway. A structural study of these two plutons, based on the anisotropy of magnetic susceptibility (AMS) technique and combined with high-precision U-Th-Pb zircon dating, is presented here. Geochronological data demonstrate a rapid emplacement of successive magmatic pulses in the Kleivan complex (from 936.94 ± 0.42 Ma to 935.62 ± 0.67 Ma) and, on the contrary, a non-negligible rest period (∼3.2 Ma) in the construction of the Sjelset complex that was formed by two pulses emplaced, respectively, at 935.67 ± 0.37 Ma and 932.43 ± 0.75 Ma. Locally discordant magnetic fabrics in the latter pluton confirm this rather protracted construction time. Thermomagnetic and hysteresis measurements supporting the AMS data indicate a magnetic mineralogy dominated by a multidomain, Ti-poor titanomagnetite, except in samples having a very low magnetic susceptibility. The susceptibility magnitudes, paramagnetic to ferromagnetic in agreement with the rock magnetic data, rely on the petrographic rock-types and on the alteration degree. Image analysis confirms that the magnetic fabric is usually coaxial with the shape fabric in both complexes, supporting the use of AMS as a proxy for the petrofabric orientation. Combined with micro- and macrostructural data, the magnetic fabric demonstrates that the Kleivan and Sjelset granitic complexes have their internal fabrics largely dominated by tectonic strain. Models of synfolding emplacement coeval with the last stage of Sveconorwegian contraction recorded in the area are proposed for the two plutons.

In presented paper magnetite nanoparticles (MNP), with various types of surface stabilizers has been fabricated. Nanostructures were obtained by thermal decomposition of Fe(acac)3 precursor in organic solutions. Five types of long-chain carboxylic acids and four types of amines were used for stabilization of nanoparticles. It was also tested, how surfactant concentration influences on the nanoparticles morphology and its properties. Obtained nanoparticles were examined by X-ray diffraction, Transmission Electron Microscopy and Infrared spectroscopy. Magnetic properties of the nanoparticles were tested by Mossbauer spectroscopy and Vibrating Sample Magnetometry. Magnetization and Mossbauer measurements show how stabilizer layer influence the magnetic state of particles. It has been analyzed the importance of the C C chain length, its spatial configuration or compound properties on magnetic state of the particles for few examples. From tested agents as a best, giving most even in shape and well distributed nanoparticles, hexylamine was selected.

In this paper, we have tested the application of magnetic susceptibility measurements in Cu-Ag-Zn-Pb-(Fe)-mineralized carbonates of the BIe subgroup (Democratic Republic of Congo) as an efficient tool for regional and global high-resolution stratigraphic correlations in the Neoproterozoic marine carbonates. To achieve this goal, we integrate the low-field magnetic susceptibility (XLF) data with facies analyses, geochemistry and isotope stratigraphy. The microfacies analyses of two cores, Tshinyama#S70 and Kafuku#15, drilled in the early Neoproterozoic carbonates of the Mbuji-Mayi Supergroup reveal a deep carbonate ramp setting associated with a microbial/stromatolitic mid-ramp environment. High-resolution stratigraphic correlations using magnetic susceptibility and C-isotope curves established for both cores, 190 km apart, suggest a sedimentary hiatus at the base of the Tshinyama#S70 succession. C-O and Sr isotopes and Sr/Ca and Fe abundances show that a diagenetic meteoric overprint affected the series of the Tshinyama#S70 core and a thermal effect related to mineralizing fluids affected the Kafuku#15 core carbonates.

As real-life experimental data on natural ventilation of atmospheric pollution levels in urban street canyons is still scarce and has proven to be complex, this study, experimentally evaluated the impact of an urban street canyon opening on local atmospheric pollution levels, during a 2-week field campaign in a typical urban street canyon in Antwerp, Belgium. Besides following up on atmospheric particulate matter (PM), ultrafine particles (UFPs) and black carbon (BC) levels, the magneto-chemical PM

Soil magnetic measurements are used increasingly to estimate the impact of airborne, combustion-related particulate matter (PM) pollution in dense measurement grids. Although many studies have proven the potential of topsoil magnetic measurements in environmental monitoring, their application is not straightforward when factors such as parent material or land use have to be accounted for. Often, the influence of land use on the soil magnetic signal is circumvented by targeting forest soils, where deposited magnetic particles are best preserved in the topsoil. However, when large forests are absent, e.g. in densely populated areas or environments with more heterogeneous land use, this approach often impedes reliable and comprehensive spatial sampling. We evaluated if topsoil magnetic pollution mapping across different land use classes, against a homogeneous geological environment of sandy soils, could help increase the spatial reliability of results in regional scale surveys. Although detailed magnetic property analysis and evaluation of trace metal concentrations in soils on arable land, forest and pasture showed the impact of atmospheric pollution, topsoil susceptibility measurements did not allow delineating the magnetic footprint of PM pollution. Land use strongly influenced the distribution of magnetic particles through soil, and the evaluation of anomalous magnetic topsoil enhancement required the integration of downhole susceptibility soundings. We conclude that topsoil susceptibility mapping remains a useful tool to evaluate PM pollution impact, yet its application potential across land use classes is limited. (C) 2019 Elsevier B.V. All rights reserved.

The discovery of Kef en-Naga site, an open-air human occupation in northeastern Algeria, was favored by a sandstone quarrying where work truncated much of the archaeological sequence on its cross-section. A multidisciplinary rescue excavation conducted on this site provided, for the first time in the region, the evidence of superimposition of two stratigraphic levels (lower and upper) of sandy clay deposits formed in humid paleoenvironmental conditions. Besides, XRD analysis show that a large amount of hematite (Fe2O3) is localized at the lower level of the stratigraphic section, where iron is found in oxide form due to the moisture. As for rock magnetic property characterization analysis, the various magnetic parameters have strong values in the upper level, and the grains are small-sized. However, various magnetic parameters are lower at the lower level and the magnetic grain concentration is reduced. Although the site is lacking faunal and carpological remains, thereby depriving us of reliable dates, the two stratigraphic levels are correlated to the Holocene according to archaeological and paleoenvironmental considerations. The lower level likely corresponding to an early Epipaleolithic culture marked by the production of microliths using a microburin blow technique, while the upper level is related to a subsequent Epipaleolithic phase, characterized by the disappearance of microburin blow technique, the dominance of an industry on flakes and the existence of pressure debitage.

Depositional changes are studied in three sections encompassing the Danian–Selandian transition, Loubieng (France), Zumaia (Spain) and Sidi Nasseur (Tunisia), using magnetic susceptibility as a proxy. Additional rock-magnetic analyses are used to avoid ambiguous interpretation of magnetic susceptibility. The magnetic susceptibility, measured on 90 to 270 samples per section, is mainly controlled by paramagnetic minerals and linked to detrital input. Major increases in the detrital input are correlated to the end of the Latest Danian Event, a hyperthermal, and to the Danian–Selandian boundary. In Loubieng, two gradual increases in magnetic susceptibility within limestones beds precede the major detrital input increases, and start synchronously with the beginning of the Latest Danian Event and the onset of haematite deposition around the Danian–Selandian boundary, respectively. This haematite is suspected to be of primary origin based, among other things, on low magnetic viscosity values, which is used here as an indicator of diagenetic origin in haematite and goethite. The red levels where haematite is interpreted to be of primary origin could be linked to the hyperthermal event previously hypothesized for the basal Selandian. The comparison of the magnetic susceptibility, chemo- and biostratigraphic data between the three sections highlights the condensed nature of the sedimentation around the Danian–Selandian boundary in the sections of the Atlantic realm. The lower part of the Selandian shows a particularly low sedimentation rate at Zumaia compared to Loubieng and Sidi Nasseur. The latter displays the most complete record of the three.

As real-life experimental data on natural ventilation of atmospheric pollution levels in urban street canyons is still scarce and has proven to be complex, this study, experimentally evaluated the impact of an urban street canyon opening on local atmospheric pollution levels, during a 2-week field campaign in a typical urban street canyon in Antwerp, Belgium. Besides following up on atmospheric particulate matter (PM), ultrafine particles (UFPs) and black carbon (BC) levels, the magneto-chemical PM10 composition was quantified to identify contributions of specific elements in enclosed versus open street canyon sections. Results indicated no higher overall PM, UFP and BC concentrations at the enclosed site compared to the open site, but significant day-to-day variability between both monitoring locations, depending on the experienced wind conditions. On days with oblique wind regimes (4 out of 14), natural ventilation was observed at the open location while higher element contributions of Ca, Fe, Co, Ni, Cu, Zn and Sr were exhibited at the enclosed location. Magnetic properties correlated with the PM10 filter loading, and elemental content of Fe, Cr, Mn and Ti. Magnetic bivariate ratios identified finel-grained magnetite carriers with grain sizes below 0.1 μm, indicating similar magnetic source contributions at both monitoring locations. Our holistic approach, combining atmospheric monitoring with magneto-chemical PM characterization has shown the complex impact of real-life wind flow regimes, different source contributions and local traffic dynamics on the resulting pollutant concentrations and contribute to a better understanding on the urban ventilation processes of atmospheric pollution.

The Lower Carboniferous Mobarak Formation in the Alborz Basin (northern Iran) was deposited along the northeastern margin of Gondwana in a carbonate ramp setting. This paper focuses on the Tournaisian stratigraphic interval of this formation that crops out at the Jaban section in the southwestern Central Alborz Basin. The following facies associations, representing different ramp palaeoenvironments, have been identified: (1) mudstone-wackestone outer-ramp facies; (2) crinoidal to skeletal grainstone-packstone mid-ramp facies; (3) peloidal to crinoidal grainstone-packstone inner-ramp facies; and (4) coastal facies, which include a variety of microbial laminated to oncoidal grainstones and mudstones with evaporitic pseudomorphs. This ramp profile was affected by frequent storms that were responsible for the formation of several skeletal to non-skeletal shoals in the distal mid-ramp to the most proximal inner-ramp areas. The development of the skeletal to non-skeletal shoals along the sea side of the ramp formed a semi-enclosed lagoon sensitive to the influence of both high tides and storm surges.The magnetic susceptibility (xin) of all the samples was measured and compared with that of the facies from which the sample was taken. There is a clear link between xin and the facies; the average xin values were higher for the distal facies than for the proximal facies. The xin profile of this Lower Carboniferous carbonate sequence reflects stratigraphic variations in response to relative changes in sea level and the input of detrital materials. In the context of the sequence stratigraphic framework, the average xin values for lowstand and transgressive systems tract deposits are higher than for the highstand systems tract deposits. The clear link between xin and facies indicates at least a partly preserved primary xin signal related to the detrital inputs. However, to obtain a better understanding of the nature and origin of the minerals carrying the xin, we performed hyster- esis measurements on selected samples. It appears that the xin signal is mainly carried by low- coercivity ferromagnetic minerals such as magnetite, with a mixture of relatively coarse grains (detrital fraction) and ultra-fine grains (probably formed during diagenesis).

International audience; Limestones at the Puech de la Suque Global Boundary Stratotype Section and Point (GSSP) of the Givetian–Frasnian boundary show a drastic change towards much higher magnetic susceptibility values in the Givetian rocks. Different rock magnetic parameters indicate that ferromagnetic minerals are the main controlling factor. The ferromagnetic fraction is composed of low- (magnetite-type) and high-coercivity (hematite and goethite) phases. Confirmed by the spectral reflectance, high coercivity minerals are fluctuating along the section with a higher abundance in the basal Frasnian. These phases may be of secondary origin and produced during burial stage. The magnetite-type phase contains two different grain-size populations. The identified that Stable Single-domain/Superparamagnetic (SSD/SP) particles are of diagenetic origin and their amount decreases slightly upwards. A second group of magnetite grains correspond to coarse-grained particles identified using the squareness v. coercive force plot. It is tentatively suggested here that these particles present throughout the section are of primary origin. On the contrary, the paramagnetic minerals underwent a clear diagenetic overprinting and may represent secondary minerals. The presence of a primary ferromagnetic carrier allowed the use of spectral analyses, leading to the detection of spectral peaks at 1.25 and 4 cycles/m, which can be interpreted as the result of 405-kyr and 100-kyr eccentricity forcing, respectively.

A new Middle Palaeolithic site was discovered at Birzgane, south of the city of Tebessa in eastern Algeria. The archaeological study revealed richness in archaeological artefacts, belonging probably to the Aterian culture, but an absence of pedunculates. The Aterian archaeological layer was assigned to the end of the Middle Pleistocene by uranium–thorium dating. The environmental conditions at the time were assessed by means of magnetic proxy data such as hysteresis parameters, magnetic susceptibility and remanent magnetisation. The magnetic fraction of the alluvial sediment contains mainly oxidised magnetite and smaller amounts of haematite and goethite; indicated by thermal demagnetisation curves of isothermal remanent magnetisation. Magnetic properties such as enhanced susceptibility, anhysteretic remanent magnetisation and frequency dependent susceptibility indicate that the upper part of the section was subjected to pedogenesis after deposition. A conceptual magnetic enhancement model was applied to reconstruct past rainfall quantities in the upper part, taking into account present day temperatures and rainfall, water saturation, soil moisture and magnetic susceptibility. A precipitation quantity of 560 ± 40 mm was estimated for the transition period from MIS 5 to 4, corresponding to the Saharan Pluvial, an extended humid climate period in northern Africa between 100,000 and 70,000 years before present.

The aim of this study is to date by the archaeomagnetic method the last heatingcooling cycle of one Roman and two Medieval tile kilns, discovered in Belgium. The investigation demonstrates the limitations when well-documented local directional secular variation curves of the geomagnetic field in the past are used for dating and the difficulties when trying to determine field intensities from “in situ” baked clays from the kilns. The three kilns yielded very well defined ancient field directions but two possible dating solutions for each of them when no a priori time constraints are taken into account, due to field direction recurrence. As an increase of the dating accuracy and reduction of the number of dating solutions can be expected using the full field vector information, also field intensity determinations on burnt clays from the kilns were attempted. Field intensities from samples of the Roman and of one of the Medieval kilns are quite scattered. On the other hand, results obtained applying the Thellier-Thellier method and the modified method developed by Dekkers and Bohnel on sister samples from the Roman kiln agree fairly well. Rock magnetic properties reveal high variance in the kilns that point to varying spatial heating and cooling conditions in the kilns. Even well burnt material from the kilns shows irreversible changes when heated in air in the laboratory. Reliable field intensities on “in situ” baked materials from kilns themselves can therefore only be obtained when measuring sufficient number of samples from different parts of the kiln, taking into account the spatial-temporal conditions during kiln operation and cooling history. More reference intensity data is needed in our regions in order to improve dating based on directional reference data only.

We carried out several experiments with carbonate-rich and clay-rich sediments that were redeposited in plastic cubes or in 1-meter-long cylindrical tubes with the aim of investigating the sensitivity of the depositional remanent magnetization (DRM) to various environmental and physical parameters. In contrast to previous studies, we did not observe any difference in the DRM acquired with or without saline water for either kind of sediment. Taking advantage of a gelatin that fixes the position of particles in suspension, we were able to measure the magnetization of suspended sediments within water-filled columns and thus to test the degree of alignment of magnetic grains. The magnetization of clay-rich sediments was not far from saturation but the magnetization was considerably reduced after deflocculation because the large flocs that favored alignment of magnetic grains were destroyed by the deflocculant. Similarly, the large flocs found at the bottom of the deposition tubes also reveal an efficient magnetic alignment. In contrast, the weak magnetization of the carbonate-rich sediments with small flocs yielded accurate and well-grouped magnetization directions that were not sensitive to deflocculation. Only a fraction of magnetic grains was mechanically oriented by the field in this case because of the weak net magnetic moments of the grains embedded within small flocs. The DRM was constrained by redeposition in plastic cubes performed without gelatin and with different field intensities. The DRM intensity of the carbonate-rich sediments is linearly related to field strength, which attests to their suitability for studies of relative paleointensity. Tests performed with mud from several stratigraphic levels in different marine sediment cores failed to reveal a significant influence of carbonate content on DRM, which suggests a relatively minor role of lithological changes on records of relative paleointensity.

Three pottery kilns from a large Hellenistic ceramic workshop at Katerini (Macedonia, Northern Greece) were studied archaeomagnetically. Palaeomagnetic investigation revealed a stable remanent magnetisation, well grouped with a mean direction of D site = 349.3, I site = 57.6 ( k = 1913.0; α 95 = 2.8). A few samples exhibited anomalous results, this behaviour being related to sample locations in the archaeological feature, where the heating was probably not homogeneous. Archaeointensity determinations gave an averaged weighted result of F site = 85.8 ± 7.8 μT. Rock magnetic analyses proved the suitability of the sampled materials for archaeomagnetic studies and revealed the presence of (metal substituted) magnetite as the main remanence carrier. Anisotropy of magnetic susceptibility and, mainly, of the remanence magnetisation showed a comparatively high degree of anisotropy. Archaeomagnetic dating was performed using the three (inclination, declination and intensity) secular variation curves for Bulgaria, by applying a recently developed hierarchical Bayesian approach. The proposed age span corresponding to the most probable last usage of the kilns is from 505 BC to 287 BC, in good agreement with the archaeological estimation.

Archaeological burnt materials and structures provide unique records of direction and intensity of the Earth’s magnetic field in the past, elements that can be absolutely determined applying the archaeomagnetic method. At present, such records within Europe are irregular in both space and time. Presented here is the archaeomagnetic investigation of three kilns that were discovered during a preventive excavation of an archaeological site considered of High Middle Age in Corroy-le-Grand (Belgium) and that are assumed to be related to iron working activities. Archaeological context dating points to kiln operation between the second half of the 10th century until the 12th century AD. As the site is not far from Paris, declination and inclination of the characteristic remanent magnetisation of the kilns were compared with the standard directional secular variation curve for France in order to propose archaeomagnetic dates for the cessation of kiln operation by using probability densities [Lanos, Ph., 2004. Bayesian inference of calibration curves, application to archaeomagnetism. In: Buck, C.E., Millard, A.R. (Eds.), Tools for Constructing Chronologies: Crossing Disciplinary Boundaries. Lecture Notes in Statistics. Springer Verlag, London, pp. 43–82; Lanos, Ph., Le Goff, M., Kovacheva, M., Schnepp, E., 2005. Hierarchical modelling of archaeomagnetic data and curve estimation by moving average technique. Geophysical Journal International 160 (2), 440–476]. This confirms the presumed archaeological age and resulted in more precise time constraints for the last kiln operation. Rock magnetic techniques, proposed by Spassov and Hus [Spassov, S., Hus, J., 2006. Estimating baking temperatures in a Roman pottery kiln by rock magnetic properties: implications of thermochemical alteration for archaeointensity determinations. Geophysical Journal International 167, 592–604], were applied to examine the suitability of the burnt materials from the kilns for archaeointensity determinations and to increase the success rate of the Thellier–Thellier double heating technique. An average value for the field intensity of 69.4 ± 2.5 lT was estimated from 10 specimens from a single kiln, which corresponds reasonably well with published data for Western Europe.

SUMMARY Absolute past geomagnetic field intensity determinations requiring laboratory heating are labourious and the success rate is rather low, mostly because of induced thermochemical magnetic mineral alterations. Archaeomagnetic intensity determinations are mainly limited to displaced ceramics produced in kilns. In this study, the suitability of an in situ baked structure is investigated. Different magnetic properties of baked material taken from the combustion chamber wall and floor of a Roman pottery kiln, with variable colouring, are examined in dependence on the distance to the combustion chamber. The temperature distribution is re-constructed based on rock magnetic experiments after stepwise heating. The rock magnetic temperature estimates agree fairly well with a mathematical heat conduction model demonstrating the penetration of heat into the combustion chamber wall. The rock magnetic results show that blackish- and greyish-coloured kiln parts, that had been in close contact with the fuel, during ancient kiln operation, are not suitable for intensity determinations. Although sufficiently baked, they strongly alter during laboratory heating and new remanence-carrying minerals are formed. The brownish-coloured material at a distance 65–80 mm away from the combustion chamber seems to be most suitable as its magnetic properties remain nearly unchanged during laboratory heating. Rock magnetic and modelled temperature estimates for this material consistently indicate ancient baking temperatures of about 600°C. The model demonstrates that cooling takes longer in the inner parts of the combustion chamber wall. Retarded cooling affects the blocking temperatures and hence the strength of the thermoremanent magnetization. The variability of cooling rates should be taken into account when investigating archaeointensities of specimens cut from large samples, or of samples taken from different parts of a kiln.

Loess/paleosol sequences in the western Black sea area at Roxolany (48 m thick) and Novaya Etuliya (30 m thick) were studied using paleo- and rock-magnetic methods in conjunction with micromorphology and Mossbauer investigations. Although seemingly complete, the sites show variability in the type and number of loess/paleosol cycles, and inconsistency of the Matuyama/Brunhes boundary (MBB) stratigraphic position. At Roxolany, nine pedocomplexes (PK) and several incipient paleosols, alternating with thick loesses, were observed with the MBB being located between PK 6 and PK 7 . At Novaya Etuliya, 13 PKs occur upon terrace XII with Khapry fauna and with the MBB in the upper part of PK 7 and the Jaramillo subchron within the lower part of PK 8 . The depth functions of rock magnetic properties, organic carbon content C org , both for bulk samples and for clay extracts, along with micromorphology and Mossbauer spectra, allowed objective identification of individual soils within PKs, and maximizing the resolution of paleopedological reconstructions of global climatic stages. The Mossbauer studies demonstrate that paleosols are basically enriched in ferric montmorillonite. Oxidized magnetite, ultrafine iron hydroxides and hematite are intimately associated with clay minerals. In contrast, Fe-compounds in loess consist mainly of ferrous silicates. These data indicate that the paleosol magnetism is basically of bio-chemogenic origin and is related to pedogenic transformation of Fe-compounds in a changing environment, while loess magnetism is primarily detrital. Pedogenic magnetically “soft” and partly oxidized magnetite may also originate during or even after burial. This ensuing transformation of Fe minerals in paleosols seems to be crucial for the understanding of the timing of natural remanent magnetization (NRM) in subaerial sediments. Given that paleosols formed on the similar parent material (loess), their typological variability seems to depend on climate and/or chronology. Hence, the different paleosol types from Roxolany and Novaya Etuliya provide key information for intra- and inter-regional correlation of loess/soil sequences, and represent valid paleoclimatic proxies.

The knowledge transfer project called "Magnetic Valley" that was launched in 2009 is presented below. This project is funded by the Belgian government to investigate and develop products and services that will improve the socio-economic development in the area around the "Centre de Physique du Globe de l'IRM".

Eight historical dacitic lava flows from Santorini with ages between 46 A.D. and 1950 A.D. (four of them within the past century) have been subjected to detailed rock magnetic analyses and various experiments of absolute paleointensity. Thermomagnetic measurements and acquisition of isothermal magnetization have revealed the presence of two physically distinct magnetic phases with Curie temperatures of 280°C and 500°C. In most of the samples, the second phase does not play a prominent role for the characteristic remanent magnetization, which is dominated by titanomagnetite. Magnetostatic interaction is very limited and does not considerably change upon heating. Back-field curve spectra indicate a good thermochemical stability of these dacitic lava samples, which is also supported by the absence of noticeable changes in the remanent coercive force prior heating to 450°C. Hysteresis measurements show typical pseudo-single-domain behavior without noticeable superparamagnetism. Such characteristics were favorable to conduct and to test the most widely used experimental approaches for absolute paleointensity determination. Despite a success rate of 38%, the microwave technique has provided rather scattered within-flow determinations. The results obtained from approaches involving alternating field demagnetization were biased by considerable differences between the NRM and the TRM coercive force spectra. We have also noticed that most determinations obtained by microwave heating differ from the historical field value at the site for the most recent flows. Last, techniques involving double-heating protocols were successful due to a dominant low Curie temperature phase with a narrow grain size distribution. The results were characterized by low dispersion and were found in good agreement with the historical field.

Environmental magnetism is a comparatively new discipline, applied in Greece only during the last decade for the study of anthropogenic pollution. The rationale of the method is based on the property of iron oxides and sulphides to attract and absorb heavy metals, organic contaminants and even radioactive pollutants. Thus, the measurement of the magnetic susceptibility, both in situ and in the laboratory, along with several other magnetic parameters constitutes a rapid and cost effective technique for characterization and mapping spatial pollution distribution. In order to quantify the correlation between magnetic susceptibility and a specific pollutant for a studied area geochemical analyses are carried out for key samples. Towards the scope of pollution assessment environmental magnetism studies have been recently carried out in the Kozani-Ptolemaida basin and the tanneries of Thessaloniki. The preliminary results of these two cases, characterized by different contaminant sources, i.e. flying ash pollution in the former and heavy metal in the latter, are presented here. In general, the application of magnetic methods proved a useful tool in the assessment of the main sources of pollution and the location of spatial distribution of major contaminants.

Iron oxide nanoparticles (IONPs) are well-known contrast agents for MRI for a wide range of sizes and shapes. Their use as theranostic agents requires a better understanding of their magnetic hyperthermia properties and also the design of a biocompatible coating ensuring their stealth and a good biodistribution to allow targeting of specific diseases. Here, biocompatible IONPs of two different shapes (spherical and octopod) were designed and tested in vitro and in vivo to evaluate their abilities as high-end theranostic agents. IONPs featured a dendron coating that was shown to provide anti-fouling properties and a small hydrodynamic size favoring an in vivo circulation of the dendronized IONPs. While dendronized nanospheres of about 22 nm size revealed good combined theranostic properties (r2 = 303 mM s−1, SAR = 395 W gFe−1), octopods with a mean size of 18 nm displayed unprecedented characteristics to simultaneously act as MRI contrast agents and magnetic hyperthermia agents (r2 = 405 mM s−1, SAR = 950 W gFe−1). The extensive structural and magnetic characterization of the two dendronized IONPs reveals clear shape, surface and defect effects explaining their high performance. The octopods seem to induce unusual surface effects evidenced by different characterization techniques while the nanospheres show high internal defects favoring Néel relaxation for magnetic hyperthermia. The study of octopods with different sizes showed that Néel relaxation dominates at sizes below 20 nm while the Brownian one occurs at higher sizes. In vitro experiments demonstrated that the magnetic heating capability of octopods occurs especially at low frequencies. The coupling of a small amount of glucose on dendronized octopods succeeded in internalizing them and showing an effect of MH on tumor growth. All measurements evidenced a particular signature of octopods, which is attributed to higher anisotropy, surface effects and/or magnetic field inhomogeneity induced by tips. This approach aiming at an analysis of the structure–property relationships is important to design efficient theranostic nanoparticles., The Region Alsace, France, and the Labex Chimie des Systemes Complexes, University of Strasbourg, France are gratefully acknowledged for the doctoral fellowship to Geoffrey Cotin. This research project was also co-funded by Labex CSC, Alsace contre le cancer, INCA (project PRTK14, THERAMAG 2014-225) and the INTERREG project NANOTRANSMED. The “NANOTRANSMED” project is co-funded by the European Regional Development Fund (ERDF) and by the Swiss Confederation and the Swiss cantons of Aargau, Basel-Landschaft and Basel-Stadt, in the framework of the INTERREG V Upper Rhine program (“Transcending borders with every project”). The authors thank Morgane Rabineau for epifluorescence imaging and Nadia Messaddeq for TEM imaging of cells. The authors thank the Center for Microscopy and Molecular Imaging (CMMI, supported by the European Regional Development Fund and the Walloon Region). This work was supported by the Fond National de la Recherche Scientifique (FNRS), UIAP VII, ARC Programs of the French Community of Belgium and the Walloon region (Gadolymph and Holocancer programs). All the authors acknowledge the COST action TD1402 “RADIOMAG”. D. Ortega and F. J. Teran acknowledge support from the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (MINECO, Grant SEV-2016-0686), the Spanish Ministry of Economy and Competitiveness for the NANOLICO project (MAT2017-85617-R), the Spanish Ministry of Science through the NaNoCAR grant PID2020-117544RB-I00, the Ramón y Cajal grant RYC2018-025253-I and Research Networks grant RED2018-102626-T, the HEATOOLS project (BIO2017-84246-C2-1-R), the Comunidad de Madrid for grant NANOMAGCOST (P2018/NMT-4321), DGA for public funding from Fondo Social (grupos DGA), and the European Commission for the funding received through the H2020 “NoCanTher” project (GA No. 685795).

The International Geoscience Program project IGCP-580 (started in 2009), focuses on the application of magnetic susceptibility (MS) as a paleoclimatic proxy on Paleozoic sedimentary rocks and on the characterization of the magnetic susceptibility signal. Here we provide a summary of the scientific targets behind the project and a summary of the organized activities. This project concerns three main issues: the first one consists of compiling the available MS data from the different researchers and continuing the collection of new data (with a main focus on the Devonian). The second issue focuses on the identification of the nature and origin of the magnetic minerals carrying MS signal. The last issue concerns the application of MS as a correlation, cyclostratigraphic and paleoclimatic tool. The IGCP-580 community consists of 245 researchers, from 45 countries (including Kenya, Namibia, Vietnam, Iran, Uzbekistan, Algeria, Tunisia, Colombia, Nigeria, India, etc.). During the project, we organized five meetings (Belgium, China, Czech Republic, Austria, Canada), three special sessions in international meetings and eight field workshops, as well as various training sessions.