SW Part Research Articles

WALNUT HUSK FLY (RHAGOLETIS COMPLETA CRESSON) IN SLOVENIA - SEASONAL DYNAMICS AS FOLLOWED IN MARIBOR (NE)

In Slovenia, walnut husk fly (WHF) was first recorded in 1997, in the SW part of the country. Nowadays, it is active all over the country except in the area close to the Slovenian - Hungarian border. Observations, performed during the year 2003, showed that in the Maribor area (NE), losses due to WHF damage exceeded 50%. Over the last three years, substantial efforts have been made to improve our knowledge of the WHF, and to find an efficient method of control. During the years 2007 and 2008, the seasonal dynamics of the WHF were followed at two locations. In 2007, flies were present from 16 July to 12 September. Using yellow sticky plates, three peaks of adult emergence (27 July, 7 August and 12 September) were recorded in Maribor, while in Razvanje, only one peak (21 August) was noted. In 2008, the adults appeared twelve days later than in the previous year, and were caught until 23 September on both locations. Two peaks of emergence have been observed in Maribor (31 July and 8 September), as well as in Razvanje (31 July and 14 August). The WHF was monitored using three types of yellow sticky plates. Considering their surface and the number of the caught flies, the plate Rebell ® amarillo (Andermatt Biocontrol AG) was the most efficient. It seems that topography of the walnut orchard (flat or slope), as well as weather conditions (presence or absence of wind) may influence the seasonal dynamics of the WHF. Long-term observations should be conducted in order to formulate efficient control measures.

Thickness of the central and eastern European lithosphere as seen bySreceiver functions

SUMMARY S receiver functions obtained from seismograms of teleseismic events recorded at 78 European permanent broad-band stations are used to estimate the thickness of the European lithosphere. Our results provide new, independent information about the lithospheric thickness beneath the Precambrian platform of Eastern Europe and the Phanerozoic platform of central Europe. Detailed high-resolution images of the lithosphere–asthenosphere boundary (LAB) reveal indications for a typical continental lithosphere of about 100 km thickness beneath a majority of stations within Central Europe, whereas in the vicinity of the Trans-European Suture Zone (TESZ), the lithosphere thickens to about 130 km. A relatively thin lithosphere of 80 km was found beneath the Upper Rhine Graben region suggesting that the Cenozoic extension affects the whole lithosphere. No clear signal from the LAB was detected beneath the Alps and Carpathians. The LAB Sp phase might be disturbed by complicated structure due to ongoing collision/subduction in these regions, or the data are not yet sufficiently dense. A relatively thicker lithosphere of about 120 km was found beneath the SW part of the Bohemian Massif that was formed during the Variscan orogeny. We found an LAB depth of about 190 km near a single station located in the Vrancea area/Eastern Carpathians, which is characterized by the occurrence of intermediate deep earthquakes. Beneath the stations located in the Precambrian platform of Eastern Europe, the LAB deepens to approximately >200 km, even though the converted phase from the LAB is not as sharp as found beneath other stations located in Central Europe or even is missing.

Sedimentation of deep-water turbidites in the SW part of the Pannonian Basin

Sedimentation of deep-water turbidites in the SW part of the Pannonian BasinThe Sava Depression and the Bjelovar Subdepression belong to the SW margin of the Pannonian Basin System, which was part of the Central Paratethys during the Pannonian period. Upper Pannonian deposits of the Ivanic-Grad Formation in the Sava Depression include several lithostratigraphic members such as Iva and Okoli Sandstone Member or their lateral equivalents, the Zagreb Member and Lipovac Marlstone Member. Their total thickness in the deepest part of the Sava Depression reaches up to 800 meters, while it is 100-200 meters in the margins of the depression. Deposits in the depression are composed of 4 facies. In the period of turbiditic activities these facies are primarily sedimented as different sandstone bodies. In the Bjelovar Subdepression, two lithostratigraphic members (lateral equivalent) were analysed, the Zagreb Member and Okoli Sandstone Member. The thickness of the Bjelovar Subdepression ranges from 50 meters along the S and SE margins to more than 350 meters along the E margin. Generally, detritus in the north-west part of the analysed area originated from a single source, the Eastern Alps, as demonstrated by sedimentological and physical properties, the geometry of the sandstone body and the fossil content. This clastic material was found to be dispersed throughout the elongated and relatively narrow Sava Depression and in the smaller Bjelovar Subdepression. Sedimentation primarily occurred in up to 200 meters water depth and was strongly influenced by the sub-aqueous paleorelief, which determined the direction of the flow of turbidity currents and sandstone body geometries. The main stream with medium- and fine-grained material was separated by two independent turbiditic flows from N-NW to the SE-E. Variability in the thickness of sandstone bodies is the result of differences in subsidence and cycles of progradation and retrogradation of turbidite fans.

The Influence of Air Temperature Inversions on Snowmelt and Glacier Mass Balance Simulations, Ammassalik Island, Southeast Greenland

Abstract In many applications, a realistic description of air temperature inversions is essential for accurate snow and glacier ice melt, and glacier mass-balance simulations. A physically based snow evolution modeling system (SnowModel) was used to simulate 8 yr (1998/99–2005/06) of snow accumulation and snow and glacier ice ablation from numerous small coastal marginal glaciers on the SW part of Ammassalik Island in SE Greenland. These glaciers are regularly influenced by inversions and sea breezes associated with the adjacent relatively low temperature and frequently ice-choked fjords and ocean. To account for the influence of these inversions on the spatiotemporal variation of air temperature and snow and glacier melt rates, temperature inversion routines were added to MircoMet, the meteorological distribution submodel used in SnowModel. The inversions were observed and modeled to occur during 84% of the simulation period. Modeled inversions were defined not to occur during days with strong winds and high precipitation rates because of the potential of inversion breakup. Field observations showed inversions to extend from sea level to approximately 300 m MSL, and this inversion level was prescribed in the model simulations. Simulations with and without the inversion routines were compared. The inversion model produced air temperature distributions with warmer lower-elevation areas and cooler higher-elevation areas than without inversion routines because of the use of cold sea-breeze-based temperature data from underneath the inversion. This yielded an up to 2 weeks earlier snowmelt in the lower areas and up to 1–3 weeks later snowmelt in the higher-elevation areas of the simulation domain. Averaged mean annual modeled surface mass balance for all glaciers (mainly located above the inversion layer) was −720 ± 620 mm w.eq. yr−1 (w.eq. is water equivalent) for inversion simulations, and −880 ± 620 mm w.eq. yr−1 without the inversion routines, a difference of 160 mm w.eq. yr−1. The annual glacier loss for the two simulations was 50.7 × 106 and 64.4 × 106 m3 yr−1 for all glaciers—a difference of ∼21%. The average equilibrium line altitude (ELA) for all glaciers in the simulation domain was located at 875 and 900 m MSL for simulations with or without inversion routines, respectively.

Effect of Tsunami in the Ilmenite Population: An Examination through X-Ray Diffraction, Scanning Electron Microscopy and Inductively Coupled Plasma Atomic Emission

Kerala state in the SW part of Indian subcontinent hosts one of the best beach placer deposits in the world. The near shore deposit is ~140Mt and is very rich in heavy minerals, often up to 70%, and ilmenite forms its chief constituent. The seasonal enrichment of this deposit takes place through monsoonal activity and the recent tsunami (24 December 2004) had significantly contributed its share. Mineralogical and chemical variation of the surface (pre- and posttsunamigenic) as well as subsurface ilmenites (4-5m depth) of this deposit has been investigated. SEM examination on ilmenites of pre-tsunamigenic period conveys that the micromorphology represents mostly of mechanical activities rather than chemical and solution activities. Both post-tsunamigenic and subsurface ilmenites were influenced dominantly by solution and chemical alteration. The pre-tsunamigenic (surficial) ilmenite grains consist only of rutile as an altered product with a small FeO – Fe2O3 ratio. However, the presence of considerable altered products such as rutile and pseudorutile in the post-tsunamigenic and subsurface ilmenite indicates that the ilmenite alteration is in an advanced state. Regarding trace element composition, it was found that Al, Mg, Na, Ca, Cd, Co, K, Sr and Pb have higher contents in both core and post-tsunamigenic ilmenite than the pre-tsunamigenic ilmenite. These elements play an important role in understanding the behavior of the minerals during beneficiation and further processing. The relative lesser content of such elements in the onshore pre-tsunamigenic ilmenite grains reveals that the chemical leaching has not been active compared to the ilmenite concentrates from the shallow sea that have been brought by the tsunami and also to that have been deposited earlier and now seen underneath up to a depth of ~5m.

A review of the Sarcophaga (Heteronychia) (Diptera: Sarcophagidae) of Sardinia

An account is given of the species of Sarcophaga Meigen, 1826 subgenus Heteronychia Brauer & Bergenstamm, 1889 known from the island of Sardinia (Italy). Most of the nearly 1,400 specimens examined were collected in the SW part of the island during 2003–2006 as part of a project investigating the arthropod diversity of the Monti Marganai and Montimannu areas (respectively Carbonia-Iglesias and Medio Campidano provinces). The study resulted in the finding of eight species of Heteronychia, six of which are recorded from Sardinia for the first time. Sarcophaga (Heteronychia) penicillata Villeneuve, 1907, previously mentioned in the literature, is excluded from the fauna of the island. Sarcophaga (Heteronychia) thirionae (Lehrer, 1976) is recorded for the first time from Europe and North Africa (Algeria). One species, Sarcophaga (Heteronychia) gabrielei sp. nov., from various sites in the limestone massif of Marganai, is described as new. Previously unpublished records from other Italian regions and from other countries (Algeria, Canary Islands, Greece) are also given for several species. Sarcophaga (Heteronychia) schnabli Villeneuve, 1911 is recognized as a junior synonym of S. (H.) consanguinea Rondani, 1860 syn. nov. The possible synanthropy of Sarcophaga (Heteronychia) pandellei (Rohdendorf, 1937) is briefly discussed. A key to males and females of all known Sardinian and Corsican species of Sarcophaga (Heteronychia) is provided.

The effect of surface variability factors on wind‐erosion susceptibility: A field study in SW Niger

AbstractThe effects of several surface treatments and factors that influence wind‐erosion susceptibility were measured with the means of a mobile wind tunnel. The test surfaces are situated in the SW part of the Republic of Niger in W Africa. The measurement program included the determination of total and dust‐mass fluxes and surface‐specific wind‐erosion parameters like aerodynamic roughness and friction velocities. Different treatments and variations were investigated on one typical and common sand surface type: different densities of stone cover, different kinds of millet‐residue alignments, and different topsoil humidities as well as the effect of different densities of fallow vegetation. The on‐site experiments in a controlled wind‐tunnel environment allowed the observation of effects that were only scarcely described in wind‐erosion literature. Increased stone cover resulted in increased emission due to increased turbulence and channelling effect, in spite of increased surface roughness. Millet‐residue alignment in transversal orientation to the wind direction resulted in far higher emission reduction as documented in the literature. Topsoil humidity, though far above the known threshold for erosion, could not completely inhibit particle entrainment because of the quick development of a thin superficial layer of dry particles.

Suture zones and importance of strike-slip faulting for Variscan geodynamic reconstructions of the External Crystalline Massifs of the western Alps

AbstractThis paper reviews the geodynamic evolution of the Belledonne, Grandes Rousses and Oisans massifs in the western Alps from Early Ordovician to Permian times. Three domains are distinguished. The eastern domain, which includes the NE Belledonne massif and the inner Oisans massif, records the subduction of the Central-European ocean along a NW dipping subduction zone. The western domain is marked by Cambro-Ordovician back-arc rifting (Chamrousse ophiolite) initiating the opening of the Rheic ocean. It was followed by Mid-Devonian obduction of the back-arc Chamrousse ophiolite, towards the NW in relation with the SE dipping subduction of the Saxo-Thuringian ocean. The central domain, including the SW part of the Belledonne massif, the Grandes Rousses massif and the outer Oisans massif, records the Devonian to Carboniferous orogenic activity that produced calc-alkaline magmatism, Mg-K granite intrusions and syn-collisional sedimentation related to Visean nappe stacking that we relate to the closure of the Saxo-Thuringian ocean. Based on tectonostratigraphic correlations we propose that these domains initially correspond to the northeastward extension of the Bohemian massif. During the late Carboniferous, the External Crystalline Massifs including Sardinia and Corsica were stretched towards the SW along the > 600 km long dextral External Crystalline Massifs shear zone. Offset of the Saxo-Thuringian and eo-Variscan suture zones from the Bohemian massif to the ECM suggests a possible dextral displacement of about 300 km along the ECM shear zone.

The South Millevaches Middle Carboniferous crustal melting and its place in the French Variscan belt

AbstractSeveral episodes of crustal melting are now well identified in the Variscan French Massif Central. Middle Devonian (ca 385-375 Ma) migmatites are recognized in the Upper and Lower Gneiss Units involved in the stack of nappes. Late Carboniferous migmatites (ca 300 Ma) are exposed in the Velay Massif only and Middle Carboniferous migmatites crop out in the Para-autochthonous Unit and southern Fold-and-Thrust Belt. In the SW part of the Massif Central, the South Millevaches massif exposes migmatites developed at the expense of ortho- and paragneiss. They form kilometer-sized septa within the foliated Goulles leucogranitic pluton, which is in turn intruded by the non-foliated Glény two micas granite pluton. Monazite grains extracted from these three rock-types have been dated by the EPMA chemical method. Three samples of migmatite yield a late Visean age (ca 337-328 Ma), the Goulles and Glény granitic plutons yield ages at 324-323 Ma and 324-318 Ma, respectively. These new results enlarge the evidence of a Middle Carboniferous crustal melting imprint that up to now was only reported in the eastern part of the French Massif Central, in the northern Cévennes and in the Montagne Noire axial zone. At the scale of the French Variscan massifs, the Visean crustal melting event is conspicuously developed since it is recognized from the Massif Armoricain (Vendée and south coast of Brittany) to the Central Vosges. This episode is synchronous with the huge thermal event responsible for the “Tuffs anthracifères” magmatism of the northern Massif Central and Vosges, and took place immediately after the last thickening phase recorded both in Montagne Noire and Ardennes, that is on the southern and northern outer zones of the Variscan Belt, respectively. However, the geodynamic significance of this major event is not fully understood yet.

Crustal structure of northeastern Tibetan plateau and Ordos block: Waveform interpretation of the Maqen-Jingbian seismic refraction profile

The Maqen-Jingbian wide-angle seismic reflection and refraction experiment was carried out in 1998, which aims at determining detailed structure in the crust and top of the upper mantle and understanding structural relation between the northeastern Tibetan plateau and the Ordos block. The 1-D crustal models inferred by waveform inversion show strong variations in crustal structure, which can be classified into four different types: ➀ an Ordos platform with the Proterozoic crust and two high-velocity layers in the northeast section, ➁ a transitional crust between the northeastern Tibetan plateau and the Ordos block across the Haiyuan earthquake zone, ➂ the Qilian orogenic zone in the central part, and ➃ the Qinling orogenic zone in the southwestern section. The Moho depth increases from ∼42 km to ∼62 km from the NE part to the SW part of the profile. The crystalline crust consists of the upper crust and lower crust in northeastern Tibetan plateau. There is an obviously low P-wave velocity layer dipping northeastward, which is 12–13 km thick, at the bottom of the upper crust in Qinling orogenic zone and Haiyuan earthquake zone. The lower crust is characterized by alternating high and low P-wave velocity layers. Beneath Ordos block, i.e., the NE part of the profile, the crust shows quite a smooth increase in P-wave velocity down to the Moho at a depth of about 42 km.

Geological interpretation of gravity profiles through the Karlovy Vary granite massif (Czech Republic)

We examined the shape of the Late Variscan Karlovy Vary granite massif located south of the Ohre/Eger graben in Northern Bohemia by reinterpretation of existing gravity data on two perpendicular profiles. The granite body of about 360 km2 total outcrop size has the elongation ratio 0.35 with the major axis trending NE-SW. The SW part of the body was crossed in the nineties by the seismic profile 9HR which localized the bottom of granites in a depth of about 10 km. We used this value as a reference datum in our gravity profiles. We positioned one of our profiles along the seismic profile 9HR and the other one perpendicularly, i.e. parallel with the elongation of the outcrop surface. We interpret the shape of the main granite body in the vicinity of Karlovy Vary as a continuous desk whose floor is horizontal (or subhorizontal) and varies along its whole extension about a depth of 10 km. This thickness is approximately identical with that of the Saxothuringian nappes imaged by seismic reflection. The near surface upper contact of the granite body is mildly inclined, and outward dipping. It changes to steep sides or inward inclined contacts in deeper levels. The Lesný-Lysina (Kynžvart) massif is a separate granite body about 324 km thick, not continuously connected with the main Karlovy Vary massif. The gravity curve suggests that granites often enclose in their endocontact large blocks of country metasediments or metabasites the existence of which is partly evidenced by their outcrops outside the line of the profile. The granite body is found density-homogenous. Minor density differences between granite varieties are caused mainly by more intense hydrothermal alterations in younger suite granites. We interpret vertical conduits for the ascent of granitic magmas to be parallel to the Jachymov-Gera and Ohře (Eger) lineaments or the Marianske Lazně fault zone as indicated by the elongation of some outcrops. However, they are not clearly imaged from the gravity data. The effect of the depression of the Sokolov basin along the faults parallel with the Ohře (Eger) lineament is shallow and it is not indicated by any change in the floor depth of the granite body. Comparison of the seismicity distribution suggests that the hypocenters occur mostly outside of the granite bodies or near their contact with the country rock.

RESOLVING THE STRUCTURE AND KINEMATICS OF THE BN OBJECT AT 0.″2 RESOLUTION

We present sensitive 7 mm observations of the H53$\alpha$ recombination line and adjacent continuum, made toward the Orion BN/KL region. In the continuum we detect the BN object, the radio source I (GMR I) and the radio counterpart of the infrared source n (Orion-n). Comparing with observations made at similar angular resolutions but lower frequency, we discuss the spectral indices and angular sizes of these sources. In the H53$\alpha$ line we only detect the BN object. This is the first time that radio recombination lines are detected from this source. The LSR radial velocity of BN from the H53$\alpha$ line, $v_{LSR} = 20.1 \pm 2.1$ km s$^{-1}$, is consistent with that found from previous studies in near-infared lines. While the continuum emission is expected to have considerable optical depth at 7 mm, the observed H53$\alpha$ line emission is consistent with an optically-thin nature and we discuss possible explanations for this apparent discrepancy. There is evidence of a velocity gradient, with the NE part of BN being redshifted by $\sim 10$ km s$^{-1}$ with respect to the SW part. This is consistent with the suggestion of Jiang et al. that BN may be driving an ionized outflow along that direction.

Fluid speciation controls of low temperature copper isotope fractionation applied to the Kupferschiefer and Timna ore deposits

Mass-balance among reduced and oxidized solution species exerts a strong control on the isotopic composition of sulphide minerals. We explore this issue for copper isotopic fractionation in sedimentary copper sulfide deposits through fluid speciation-isotopic Eh–pH calculations based on the thermodynamic stability of copper chloride aqueous solution complexes and experimentally measured copper isotope fractionation factors. Applying these speciation diagrams to MC-ICP-MS copper isotope data on the Kupferschiefer (SW part of the Lubin-Sieroszowice Copper District) and Timna (S. Israel) Sediment-hosted Stratiform Copper deposits (SSC), identifies differences in ore formation redox conditions. Timna Valley copper sulfides have light Cu-isotopic compositions of δ 65Cu = − 2.04 ± 0.44‰ 2σ (relatively to SRM 976 copper standard), which are shown to correspond to Eh values of 0.5 to 0.6 V at formation conditions (T = 40 °C; pH < 6). These Eh values indicate precipitation at relatively oxidized conditions where the Cu(I) solution complex (CuCl 3 2−) is < 10% of the total solution species. In contrast, the Kupferschiefer Cu-sulfides analyzed in this work dominantly show significantly higher δ 65Cu values = − 0.39 ± 0.36‰, corresponding to Eh values of 0.4 to 0.5 V at formation conditions (T = 100 °C; pH = 6.3). In these Eh conditions, most copper in solution occurs as CuCl 3 2− complexes (~ 80%). The above observations are in accord with field relations showing that Cu(II) minerals dominate the Timna system, but Cu-sulfides are the major minerals of the Kupferschiefer deposits. Fluid speciation–isotopic calculations show that copper isotopes can be used as effective tracers of redox conditions and this approach can be potentially applied to various hydrothermal ore deposits, such as black smokers and volcanic-hosted massive sulphide deposits, and to other metallic isotope systems. However, the isotopic fractionation may also be strongly influenced by the types of ligand bonding of copper ions and these effects need to be fully evaluated before the isotope geochemistry of copper ores can be fully understood.

Variability of selected extreme meteorological events in Poland

The principal aim of this paper is to analyze the trends of the multi-annual course of the selected characteristics of extreme precipitation, snow cover and atmospheric thunderstorms in the second half of the twentieth century in Poland. The results of these investigations show that in Poland it is only possible to determine a weak decreasing trend of extreme precipitation events in the S and especially in the SW part of the country. In northern Poland, opposite, although similarly weak, trends have also been observed. It is assumed that the most essential features of long-term changeability of extreme precipitation include a higher than average number of days with extremely high precipitation during the 1960s and 1970s, a distinctly lower frequency of such days during the 1950s, 1980s and in the first half of the1990s. In Poland it is possible to distinguish four broad homogenous areas in terms of the long-term changes in the occurrence of extreme precipitation events. There is considerable regional differentiation when it comes to the occurrence of thunderstorms in Poland, and their long-term changeability does not show any clear trends. Only three stations have determined a weak increase in the number of thunderstorms during the last 120 years. In some stations, an increase in the number of days with thunderstorms during the winter seasons was also observed. There were no significant trends in extreme snow cover in Poland. The periods that contained large and small areas of extreme snow cover thickness occurred alternately. Since the winter season 1987/88, the area of extremely thin snow cover has remained at a relatively high level.

Geocronologia Rb-Sr e Características Geoquímicas dos Diques Máficos da Região de Nova Lacerda e Conquista D’Oeste (MT), Porção Sudoeste do Craton Amazônico

In the Nova Lacerda and Conquista D’Oeste regions, Mato Grosso State, SW part of the Amazonian Craton, mafic dikes trending NNW intrude the Nova Lacerda Granite (1462 ± 12 Ma), within the Jauru Domain, in the Rondonia-San Ignacio Province (1.55 - 1.3 Ga). The mafic swarm comprises diabases, metadiabases and amphibolites. Metadiabases originated from uralitization of diabases. These rocks have tholeiitic affinity and predominant basaltic composition. Some samples are andesi-basalts. The ages of diabases and metabasites are 1380 ± 32 Ma and 1330 ± 120 Ma respectively. Geochemical data indicate that the compositional variation of diabases and metadiadases is due to fractional crystallization of evolved tholeiitic magmas. The origin of the basaltic magmas is related to a heterogeneous mantle source

Three decades of land use variations in Mexico City

Uncontrolled urbanization is one of the most important problems of our changing world. Land use change evaluation is an important tool in planning further development in populated areas. This paper reports the results of an investigation on integration of remote sensing and geographic information systems (GIS) to detect urban growth. Here, we attempt to determine urban area growth in the SW part of Mexico City by using multi‐temporal MSS NALC images (1973), Landsat TM images (1992) and a 2000 ETM+ image. Techniques on change detection evaluation were employed to identify areas of urban encroachment. Statistics on development stages of the expanded urban areas were generated and various thematic maps were produced. Remote sensing techniques were used to carry out land use/land cover change detection by using multi‐temporal Landsat data. Urban growth patterns were analysed by using a GIS‐based modelling approach. The images were processed to enhance the spectral response of the surface materials and define land cover types that characterize distinct land uses in the study area. After processing, the signatures typical of the most important land use types were obtained. Supervised classification procedures were applied to all images and the resulting evaluation of land use changes in the Mexico City urban area was plotted. Quantitative results of changes, which were computed with a post‐classification method, were used to analyse the change pattern in urban land classes. Ground data were gathered from aerial photographs taken in 1973, 1992 and ortho‐photographs taken in 2000 to determine the accuracy of the classification method. Results show that the urbanized area surrounding the SW part of Mexico City has expanded at a maximum rate of 36.29% during the 1980s. The integration of remote sensing and GIS was found to be effective in monitoring and analysing urban growth patterns.

Mollusc grazing may constrain the ecological niche of the old forest lichen Pseudocyphellaria crocata

This study reports on mollusc grazing of two epiphytic cyanobacterial lichens (Pseudocyphellaria crocata and Lobaria pulmonaria) transplanted within three Picea abies-dominated boreal rain forest stands (clear-cut, young and old forests) in west central Norway. Grazing was particularly high in transplants located in the old forest and was almost absent in clear-cut transplants. Grazing marks were absent on natural thalli on nearby spruce twigs (required creeping distance for mollusc from the ground >4 m). Transplantation of lichens from twigs to artificial transplantation frames reduced the creeping distance to 1.2 m, and caused a significant increase in grazing damage in P. crocata. Given a paired choice under transplantation, molluscs consistently preferred P. crocata and avoided L. pulmonaria, implying species-specific differences in herbivore defence. Pseudocyphellaria crocata has a much lower content of the medullary depsidones stictic and constictic acid than L. pulmonaria. Heavy grazing occurred in the P. crocata thalli lowest in these two depsidones. The upper part of the medulla hosting the photobiont was the preferred fodder for grazing molluscs. Molluscs avoided the yellow soralia in P. crocata (localised pulvinic acid), suggesting a role for pulvinic acid in preventing grazing of detached soredia and early establishment stages. The preference of P. crocata for thin spruce twigs is probably a result of a lower grazing pressure on twigs compared to e.g. deciduous stems that frequently support the better defended L. pulmonaria. Ongoing climate changes with increased annual rainfall and milder winters have presumably increased mollusc grazing, particularly in SW parts of Norway which have more species of lichen-feeding molluscs than the boreal sites studied. These temperate areas lacking natural spruce populations have recently experienced reported extinctions of the poorly defended P. crocata from rocks and deciduous stems prone to mollusc grazing. Lichen-feeding molluscs have likely played a role in these extinctions, causing spruce twigs in Atlantic boreal forests to be a last strong foothold for P. crocata in Scandinavia.

Uplift and late orogenic deformation of the Central European Variscan belt as revealed by sediment provenance and structural record in the Carboniferous foreland basin of western Poland

The Carboniferous foreland basin of western Poland contains a coherent succession of late Visean through Westphalian turbidites derived from a uniform group of sources located within a continental magmatic arc. Detrital zircon geochronology indicates that two main crustal components were present in the source area of Namurian A sediments. They represent Late Devonian and Early Carboniferous ages, respectively. The detritus from Westphalian D beds is much more diversified and contains admixture of Late Carboniferous zircons suggesting rapid unroofing of Variscan igneous intrusions in the hinterland between Namurian A and Westphalian D times. Tectonic repetitions of tens of metres thick fault-bounded stratigraphic intervals, recorded in several wells, provide evidence for compressional regime that occurred in the SW part of the Carboniferous basin not earlier than during the Westphalian C and produced NW-SE trending folds, concordant with the structural grain of the adjacent, NE part of the Bohemian Massif.

The Rila-Pastra Normal Fault and multi-stage extensional unroofing in the Rila Mountains (SW Bulgaria)

The Rhodope Metamorphic Province represents the core of an Alpine orogen affected by strong syn- and postorogenic extension. We report evidence for multiple phases of extensional unroofing from the western border of the Rila Mountains in the lower Rila valley, SW Bulgaria. The most prominent structure is the Rila-Pastra Normal Fault (RPNF), a major extensional fault and shear zone of Eocene to Early Oligocene age. The fault zone includes, from base to top, mylonites, ultramylonites and cataclasites, indicating deformation under progressively decreasing temperature, from amphibolite-facies to low-temperature brittle deformation. It strikes E–W with a top-to-the-N-to NW-directed sense of shear. Basement rocks in the hanging wall and footwall both display amphibolite-facies conditions. The foliation of the hanging-wall gneisses, however, is discordantly cut by the fault, while the foliation of the footwall gneisses is seen to curve into parallelism with the fault when approaching it. Two ductile splays of the RPNF occur in the footwall, which are subparallel to the foliation of the surrounding gneisses and merge laterally into the mylonites of the main fault zone. The concordance between the foliation in the footwall and the RPNF suggests that deformation and cooling in the footwall occurred simultaneously with extensional shearing, while the hanging-wall gneisses had already been exhumed previously. The RPNF is associated with thick deposits of an Early Oligocene, syntectonic breccia on top of its hanging wall. Integrating our results with previous studies, we distinguish the following stages of extensional faulting: (1) Late Cretaceous NW–SE extension (Gabrov Dol Detachment), exhumation of the present day hanging wall of the RPNF; (2) Eocene to Early Oligocene NW–SE to N–S extension (RPNF); (3) Miocene to Pliocene E–W extension (Western Border Fault), formation of the Djerman Graben; (4) Holocene to recent N–S to NW–SE extension (Stob Fault), reactivating the SW part of the Western Border Fault.

Palaeo-hydrogeological control on groundwater As levels in Red River delta, Vietnam

To study the geological control on groundwater As concentrations in Red River delta, depth-specific groundwater sampling and geophysical logging in 11 monitoring wells was conducted along a 45 km transect across the southern and central part of the delta, and the literature on the Red River delta's Quaternary geological development was reviewed. The water samples (n=30) were analyzed for As, major ions, Fe 2+ , H 2 S, NH 4 , CH 4 , δ 18 Ο and 8D, and the geophysical log suite included natural gamma-ray, formation and fluid electrical conductivity. The SW part of the transect intersects deposits of grey estuarine clays and deltaic sands in a 15-20 km wide and 50-60m deep Holocene incised valley. The NE part of the transect consists of 60-120 m of Pleistocene yellowish alluvial deposits underneath 10-30m of estuarine clay overlain by a 10-20m veneer of Holocene sediments. The distribution of δ 18 O-values (range -12.2‰ to -6.3%o) and hydraulic head in the sample wells indicate that the estuarine clay units divide the flow system into an upper Holocene aquifer and a lower Pleistocene aquifer. The groundwater samples were all anoxic, and contained Fe 2+ (0.03-2.0mM), Mn (0.7-320μM), SO 4 (<2.1μM-0.75mM), H 2 S (<0.1-7.0μM), NH 4 (0.03-4.4 mM), and CH 4 (0.08-14.5 mM). Generally, higher concentrations of NH 4 and CH 4 and low concentrations of SO 4 were found in the SW part of the transect, dominated by Holocene deposits, while the opposite was the case for the NE part of the transect. The distribution of the groundwater As concentration (<0.013-11.7 μM; median 0.12 μM (9μg/L)) is related to the distribution of NH 4 , CH 4 and SO 4 . Low concentrations of As (≤0.32μM) were found in the Pleistocene aquifer, while the highest As concentrations were found in the Holocene aquifer. PHRE-EQC-2 speciation calculations indicated that Fe 2+ and H 2 S concentrations are controlled by equilibrium for disordered mackinawite and precipitation of siderite. An elevated groundwater salinity (Cl range 0.19-65.1 mM) was observed in both aquifers, and dominated in the deep aquifer. A negative correlation between aqueous As and an estimate of reduced SO 4 was observed, indicating that Fe sulphide precipitation poses a secondary control on the groundwater As concentration.