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This study analyzes the microstructures and deformational characteristics of spinel peridotite xenoliths from the Nógrád-Gömör Volcanic Field (NGVF), located on the northern margin of a young extensional basin presently affected by compression. The xenoliths show a wide range of microstructures, bearing the imprints of heterogeneous deformation and variable degrees of subsequent annealing. Olivine crystal preferred orientations (CPOs) have dominantly [010]-fiber and orthorhombic patterns. Orthopyroxene CPOs indicate coeval deformation with olivine. Olivine J indices correlate positively with equilibration temperatures, suggesting that the CPO strength increases with depth. In contrast, the intensity of intragranular deformation in olivine varies as a function of the sampling locality. We interpret the microstructures and CPO patterns as recording deformation by dislocation creep in a transpressional regime, which is consistent with recent tectonic evolution in the Carpathian-Pannonian region due to the convergence between the Adria microplate and the European platform. Postkinematic annealing is probably linked to percolation of metasomatism by mafic melts through the upper mantle of the NGVF prior to the eruption of the host alkali basalt. Elevated equilibration temperatures in xenoliths from the central part of the volcanic field are interpreted to be associated with the last metasomatic event, which only shortly preceded the ascent of the host magma. Despite well-developed olivine CPOs in the xenoliths, which imply a strong seismic anisotropy, the lithospheric mantle alone cannot account for the shear wave splitting delay times measured in the NGVF, indicating that deformation in both the lithosphere and the asthenosphere contributes to the observed shear wave splitting., The authors would like to thank the people who contributed to this work. We owe thanks to Fabrice Barou and David Adams for their help with EBSD-SEM analyses at Geosciences Montpellier and at CCFS Macquarie University, respectively. L?szl? Aradi is acknowledged for his help with field work, petrography and MTEX application. We are grateful for the constructive criticism of Sandra Piazolo and Jacques Pr?cigout and two anonymous reviewers, as well as for the editorial handling of Stephen Parman. Our research received financial support from a Marie Curie International Reintegration Grant (grant NAMS-230937), a postdoctoral grant (grant PD101683) of the Hungarian Scientific Research Fund (OTKA), and a Bolyai J?nos Postdoctoral Research Fellowship of the Hungarian Academy of Sciences to I. J. K., as well as from the Lend?let Pannon LitH2Oscope Research Group (Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences). N. L. received support from Macquarie University international PhD scholarship and project and travel funding from ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS). K. H. acknowledges funding from Ministry of Economy, Industry and Competitiveness (MINECO, Spain) and the State Research Agency (AEI, Spain; grants FPDI-2013-16253 and CGL2016-81085-R). Instruments used at Macquarie University are funded by DEST Systemic Infrastructure Grants, ARC LIEF, NCRIS/AuScope, industry partners, and Macquarie University. The data used in this paper are listed in the references, tables, and supporting information. The raw EBSD data are available from the corresponding author upon request. This is the 92nd publication of the Lithosphere Fluid Research Lab (LRG), contribution 1361 from the ARC Centre of Excellence for Core to Crust Fluid Systems (www.ccfs.mq.edu.au) and 1320 from the GEMOC Key Centre (www.gemoc.mq.edu.au).

We present a new method for identifying the source regions of lightning generated whistlers observed at a fixed location. In addition to the spatial distribution of causative lightning discharges, we calculate the transmission ratio of lightning discharges into ground detectable whistlers as a function of location. Our method relies on the time of the whistlers and the time and source location of spherics from a global lightning database. We apply this method to whistlers recorded at fifteen ground based stations in the AWDANet (Automatic Whistler Detector and Analyzer Network) operating between 2007-2018 and to located lightning strokes from the WWLLN (World Wide Lightning Location Network) database. We present the obtained maps of causative lightning and transmission ratios. Our results show that the source region of whistlers corresponding to each ground station is around the magnetic conjugate point of the respective station. The size of the source region is typically less than 2000 km in radius with a small fraction of sources extending to up to 3500 km. The transmission ratio is maximal at the conjugate point and decreases with increasing distance from it. This conforms to the theory that whistlers detected on the ground propagated in a ducted mode through the plasmasphere and thus the lightning strokes of their causative spherics must cluster around the footprint of the ducts in the other hemisphere. Our method applied resolves the whistler excitation region mystery that resulted from correlation-based analysis methods, concerning the source region of whistlers detected in Dunedin, New Zealand., 22 pages, 10 figures, submitted to Journal of Geophysical Research, Space Physics

In this study we present an inversion method which provides thermal plasma population parameters from characteristics of chorus emissions only. Our ultimate goal is to apply this method to ground based data in order to derive the lower energy boundary condition for many radiation belt models. The first step is to test the chorus-inversion method on in-situ data of Van Allen Probes in the generation region. Density and thermal velocity of energetic electrons (few keV - 100 keV) are derived from frequency sweep rate and starting frequencies of chorus emissions through analysis of wave data from Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) onboard the Van Allen Probes. Nonlinear wave growth theory of \citet{omura2011triggering} serves as the basis for our inversion method, assuming that the triggering wave is originated by the linear cyclotron instability. We present sixteen, consecutive rising-tone emissions recorded in the generation region between 11-12UT on 14 November 2012. The results of the inversion are compared with density and thermal velocities (parallel and perpendicular) of energetic electrons derived from unidirectional flux data of Helium Oxygen Proton Electron (HOPE) instrument, showing a good agreement: the normalized root-mean-square deviation between the measured and predicted values are $\sim13\%, \sim6\%$, and $\sim10\%$, respectively. We found that the theoretical amplitudes are consistent with the measured ones. The relation between linear and nonlinear wave growth agrees with our basic assumption, namely, linear growth is a preceding process of nonlinear wave growth. We analyze electron distributions at the relativistic resonant energy ranges., Comment: 15 pages, 5 figures

The objective of our paper is to develop a workflow that allows us to calculate more accurate hypocenter locations in seismic event clusters of aftershock sequences or artificial events. Due to the increased sensitivity of the seismological instruments and density of the network, we are able to record small natural and artificial events. The discrimination of these events is necessary to investigate the recent tectonic movements in the Pannonian Basin. As a first step, we performed a hierarchical cluster analysis on the events in the Hungarian National Seismological Bulletin using the spatial distances between the events to obtain event clusters. We selected 5 different test clusters from the list of clusters where two clusters consist of quarry blasts, another two consist of earthquakes, and the last one is a mixture of earthquakes and anthropogenic events. In the second step, to prepare for the double-difference multiple event location analysis, we manually revised the arrival time picks in the Hungarian National Seismological Bulletin in order to increase the consistency and accuracy of the arrival times. We obtained improved single-event locations with the iLoc algorithm using the RSTT 3D global velocity model to provide initial locations for the double-difference relocation. We applied waveform cross-correlation at every station to obtain the differential times and correlation matrices. In order to discriminate the events in the mixed event cluster, we repeated the hierarchical cluster analysis, but this time, we used the correlation matrix as a distance metric. Examining the shape of the resulting dendrogram, it is clear that certain subclusters are well separated. In these subclusters, the coordinates of the events are close to the mines, where explosive quarrying takes place. With this technique, we are able to identify explosions that were listed as earthquakes in the catalogue.

Receiver function analysis is performed for the easternmost part of the Pannonian Basin and across the Southern Carpathians, a geologically and geodynamically complex region featuring microplates, mountain belts, and locally deep sedimentary basins. We exploited seismological data of 56 stations including temporary broadband stations of the South Carpathian Project (SCP) and two permanent stations in Hungary. We calculated P-to-S receiver functions to determine the variation of Moho depth across the basin and the mountains along a NW–SE-oriented swath about 600 km long and 200 km wide. We applied threefold quality control on the raw and the processed data. The Moho depth was determined by two independent approaches, common conversion point migration and H-K grid search method. The determined Moho depths show shallow values between the AlCaPa and the Tisza-Dacia blocks, with typical depths between 22 and 28 km, and the shallowest depths in the area of eastern Pannonian Basin. We could estimate the Moho depth beneath one station in the Mid-Hungarian Zone, between the AlCaPa and the Tisza-Dacia blocks. The crust was thicker under the Apuseni Mountains (28–32 km), and in the investigated region, the Moho was deepest beneath the Southern Carpathians (33–43 km). We observed a southeastward crustal thickness increase, and we presented an interpolated Moho map over the area of study.

This study aims to investigate the radioactivity of adobe in Angola, where it is a widely used building material. Sixty samples have been collected from three remote areas of the country with different geological backgrounds (Cabinda, Huambo, Menongue). Activity concentrations of226Ra,232Th and40K have been determined by gamma-ray spectroscopy and radiation hazard indices were also calculated. The area Huambo shows elevated226Ra and232Th values which can be explained by its older geological formations.40K concentrations are low in general. Regarding external radiation risk, adobe from Angola is safe to use as building material.