interpretation of tectonic stress orientation on the basis of laboratory model experiments abstract to study the orientation of the tectonic stress in the earth s crust we used physical modelling this method takes advantage of a wide variety of experiments on fault models which were uniaxially loaded to compare the results of laboratory experiments with the behaviour of actual seismoactive fault systems we used the commonly available tectonic and seismic information the structure of fault systems and principal parameters of seismic events i e location origin time and magnitude the possibilities of physical modelling to reconstruct the tectonic stress orientation in actual fault zones are demonstrated on examples from northwestern china the bear valley section of the san andreas fault and from west bohemia czechoslovakia despite several restrictions which up to now have limited the use of the method physical modelling seems to be promising as even complicated patterns of seismic energy release can be explained by means of simple tectonic conditions

the history of danube loess research the loess paleosol sequences of the danube basin contain the longest and most complete terrestrial records of middle and late pleistocene paleoclimates in europe consequently it is no surprise that scientific research into european loess began in this region and has a long and distinguished history european loess research was initiated by count marsigli in the serbian vojvodina in the late 17th century formed the focus of the international loess commission which straddled both sides of the iron curtain from 1961 and culminated with george kukla s seminal studies in the 1970s correlating the loess archives with deep sea sediments the rise in popularity of the longer chinese loess sequences in the early 1980s shifted the international research focus away from europe and it was not until the change of century that scientific investigation intensified in the region this time with much more sophisticated tools for analysis despite its potential as one of europe s most valuable quaternary archives scientific research into danube loess has until recently been hindered both by landscape heterogeneity and the large number of countries it covers these have presented a major limiting factor in developing a unified research approach for decades regional national loess stratigraphic models were defined separately difficulties in correlating such schemes persist especially since these often change significantly with advances in dating methodologies a cooperative effort is necessary to synthesize the available data which requires not only the insights from but also the perspective provided by an appreciation of the history of the research in this study we present a critical historical overview of loess research in the danube region we classify the major research phases throughout the long tradition of danube loess investigations into five categories 1 the early period late 17th century until 1920 extending from marsigli to penck 2 the classic period 1920 1961 encompassing the contributions of milankovic and the development of pedostratigraphy 3 the modern period 1961 present which oversaw czech innovations and developments in geochronologic methods in particular amino acid racemisation aar and luminescence dating and 4 contemporary research from bronger s unified pedostratigraphy to orbitally tuned timescales finally 5 we present a vision of future danube loess research

geological hazards in loess terrain with particular reference to the loess regions of china abstract the considerable morphodynamic energy provided by the continuing tectonic evolution of asia is expressed in high erosional potentials and very high rates of sediment production that make this continent unequalled as a terrestrial source of primary silt many of these environments are hazardous threatening human occupation health and livelihood especially in regions of dense population such as the loess lands of north china dry loess can sustain nearly vertical slopes being perennially under saturated however when locally saturated it disaggregates instantaneously such hydrocompaction is a key process in many slope failures made worse by an underlying mountainous terrain of low porosity rocks gully erosion of loess may yield very high sediment concentrations 60 by weight characteristic vertical jointing in loess influences the hydrology enlarged joints develop into natural sub surface piping systems which on collapse produce a loess karst terrain collapsible loess up to 20 m thick is common on the western loess plateau foundation collapse and cracked walls are common many rapid events following periods of unusually heavy monsoonal rain slope failure is a major engineering problem in thick loess terrain flow slide and spread types being common the results are often devastating in both urban and rural areas an associated hazard is the damming of streams by landslides the human population increases the landslide risk in china notably through imprudent land use practices including careless water management a number of environmentally related endemic diseases arise from the geochemistry of loess and its groundwaters including fluorosis cretinism kaschin beck disease keshan disease and goitre the chinese desert margins also have a major atmospheric dust problem the effect of such dust upon human health in these extensive regions including many large cities has yet to be evaluated but pneumoconiosis is thought to affect several million people in north and west china

laboratory investigation into off fault seismic activity abstract the off fault pattern of weak seismic activity which was observed in the laboratory around fault pairs with already generated tensile cracks led to the comparison with similar patterns observed in nature in some seismoactive regions on the basis of the results of the laboratory model experiments the off fault seismic activity can be attributed to fault segments oriented obliquely or roughly perpendicular to the main fault system these fault segments may have originated as tensile fractures during one of the foregoing strong earthquakes to study the off fault foreshock and aftershock occurrences a method of laboratory seismology physical modeling was employed the use of this method is based on the assumption that the obtained information on the seismic regime of fault models is relevant to the seismic manifestation of faults in the earth the results of laboratory experiments can thus be used to analyze the pattern of seismic energy release in selected seismoactive fault regions

optical dating of romanian loess a comparison between silt sized and sand sized quartz abstract the loess palaeosol sequence near mircea vod dobrogea se romania is thought to comprise at least five glacial interglacial cycles it is considered as one of the most significant records of late quaternary environmental and climatic change in the region age information for the sequence was previously obtained through time depth modeling of magnetic susceptibility data and optically stimulated luminescence dating osl of fine silt sized 4 11 m quartz this study documents the granulometric properties of the sequence and compares the osl characteristics and age of fine sand sized 63 90 m quartz to those of silt sized quartz osl signals from both sand and silt sized quartz are dominated by a thermally stable fast decaying component a suite of laboratory test confirms that the single aliquot regenerative dose sar protocol is suitable for these samples each grain size fraction yields a set of optical ages that is consistent with the stratigraphic position of the samples the ages obtained using sand sized grains however are up to 70 higher than those obtained using silt sized quartz the discrepancy in age results is not understood as according to procedural tests the osl signal from both fractions should be suitable for dating the deposits as such it cannot be established whether the uppermost weakly developed palaeosol was formed during mis3 or mis5 and if the rate of loess accumulation varied during the last glacial only by using standard sar osl techniques both sets of ages do confirm however that the first well developed palaeosol s1 is of last interglacial age

geochronology of middle and upper pleistocene loess sections in hungary abstract the application of both thermoluminescence and infrared stimulated luminescence dating to the extensively studied classical hungarian loess paleosol sequences from basaharc mende and paks provides a reliable chronological framework and climatostratigraphic reconstruction for the last interglacial glacial cycle based on this combined luminescence dating study a new chronology is proposed for the young loess in hungary luminescence dating suggests that the loess below the mf2 horizon formed during the penultimate glaciation the mf1 horizon probably formed during an interstade within oxygen isotope stage 3 for the youngest loess overlying mf1 a very high accumulation rate was determined large time gaps occur above mf2 and mf1 indicating that most of the record of the last glaciation is missing in the standard sections at basaharc mende and paks either large discontinuities or a very low accumulation rate occurred in all three type sections during the soil forming periods high resolution studies of climatic proxies using this combined luminescence dating approach provide a reliable chronological framework for loess and loess derivatives of the last glacial cycle in hungary although a precise and complete chronostratigraphic reconstruction cannot be achieved from the incomplete records found at these sites

fault interaction and seismicity laboratory investigation and its seismotectonic interpretation systems of two parallel linear faults of the same length with the angle of inclination 45 were investigated under uniaxial linearly increasing load perspex plates were used as models for each treated fault configuration the morphology of tensile cracks and the sequence of seismoacoustic events of shear and tensile origin were studied

weathering and clay mineral formation in two holocene soils and in buried paleosols in tadjikistan towards a quaternary paleoclimatic record in central asia abstract the upper part of the karamaydan section tadjikistan shows the most detailed loess paleosol sequence yet known for the brunhes chron and the central and lower parts of the chashmanigar section provide similar detail for most of the matuyama chron to enable paleoclimates to be deduced the primary and secondary minerals in the silt and clay fractions must be determined separately to evaluate the type and intensity of mineral weathering and clay mineral formation to distinguish between inherited and pedogenetically formed clay minerals the original petrographic homogeneity of the parent material from which a soil developed must be established the main sources of pedogenic clay minerals are phyllosilicates in the silt fractions illites and vermiculites are the dominant pedogenetically formed clay minerals in the b or bt horizons of the holocene climaphytomorphic soils and in all paleosols s and pedocomplexes pk in karamaydan and chashmanigar except s xvii in which large amounts of smectites were formed there is little difference in the type and amount of pedogenic clay mineral formation between the holocene soils and the paleosols in the brunhes epoch at karamaydan as well as during most of the matuyama epoch at chashmanigar these results indicate that the climates of the interglacials represented by the b or bt horizons of the buried paleosols of young mid and old pleistocene age were similar to that of the holocene

malacological and sedimentological evidence for warm glacial climate from the irig loess sequence vojvodina serbia four loess units and three paleosol layers are preserved in the irig brickyard vojvodina serbia amino acid geochronology provides stratigraphic correlations between loess units v l1 and v l2 at the irig section with loess of glacial cycles b and c respectively described from other central european localities luminescence dating results for the upper loess layers v l1l1 and v l1s1l1 confirm the geological interpretations although in samples below paleosol v l1s1s2 the age increase with depth is less than in our proposed age model magnetic susceptibility and sedimentological evidence from the irig loess paleosol sequence show general similarities with the mis 6 1 pattern of the specmap oxygen isotope curve malacogical investigations at the irig site reveal the continuous presence of the chondrula tridens and helicopsis striata faunal assemblages throughout the last glacial and final part of the penultimate glacial loess the loess snail fauna which is characterized by the complete absence of cold resistant species suggests a stable dry and relatively warm glacial climate compared with other central european loess localities furthermore these data suggest that the southern slope of fruska gora was a refugium for warm loving and xerophilus mollusc taxa during the otherwise unfavorable glacial climates of the late pleistocene

research on the geometry of shear fracture zones the geometry of brittle shear fracture zones has been studied by the examination of some strike slip faults and shear joints in china pinnate and en echelon deformational patterns are two fundamental arrangements of fractures within brittle shear fracture zones the pinnate angle is usually less than 25 and the en echelon is more than 25 the deformation in the rock bridge the area between two secondary fractures depends on the arrangements of secondary fractures and the sense of shear some tensile ruptures are formed at the terminations of both primary shear fracture zones and secondary fractures the direction of a tensile rupture is commonly parallel to the orientation of the principal compression along the direction of propagation of the shear fracture the horizontal displacement is large and the attenuation of displacements is slow the maximum horizontal displacement of the shear zone may be located in the region of the initial fracture under certain conditions the shear fracture zones may possess pivotal movement this type of movement may be expressed by the behavior of the fault or by the geomorphology of the fault zone

spatial and temporal analysis of a seismic series using a new version of the three point method application to the 1989 antequera spain earthquakes abstract the three point method tpm has been successfully applied to several seismic series and has provided information about the spatial characteristics azimuth and dip of the fault planes activated in the rupture process a new development of the tpm to determine temporal characteristics is presented to obtain the evolution of the fracturing process of an active fault system for the analysis of the 158 microearthquakes and earthquakes that took place in the seismic series of antequera in june 1989 the choice of a threshold magnitude m u 2 5 has permitted the events related to the most relevant fractures to be distinguished secondly only the events between two concentric spheres here named spatial crown with respect to a given earthquake have been used in order to avoid taking into account earthquakes that are too close to each other together with the very distant events that have little relation to the event analysed the spatial crown has permitted some clear results in the antequera series where we have found that the fracturing process began fundamentally with n 80 e planes and evolved to n 65 w planes finally an error analysis enables an estimation of the uncertainty in the results to be obtained from the errors in the data

the loess paleosol sequence of basaharc hungary revisited mollusc based paleoecological results for the middle and upper pleistocene abstract the present study discusses the findings of detailed stratigraphical sedimentological geochemical and paleoecological investigations implemented as part of a 1990 campaign to pecsi s studied profile at hungary s important danubian loess profile at basaharc in older studies there were major discrepancies between the old lithostratigraphic classifications and the numerical ages according to the findings of this study the basaharc double paleosol complex described formerly from the lower brickyard as a stratotype of middle wurmian is an isochronous heterotype of the mende upper paleosol complex from profile 1 due to reworking however the lower member of the mende upper paleosol complex must have formed not at the boundary of the upper and middle wurmian as originally presumed but during the riss wurmian interglacial conversely the upper member of this same complex developed during an interglacial between the upper and middle wurmian implying the presence of a huge erosional hiatus between the two members of the paleosol complex the genetics of the individual paleosol layers needs a re evaluation as well the majority of the soils formerly conceived to be of steppe and forest steppe origin developed among closed woodland conditions

ice volume forcing of east asian winter monsoon variations in the past 800 000 years particle size measurements of some typical loess soil samples taken in different localities of the chinese loess plateau demonstrate that the grain size ratio of 10 m can be used as an indicator of variations in intensity of the east asian winter monsoon winds grain size curves of the baoji and weinan sections show that this proxy indicator is very sensitive to loess soil alterations analytical results also suggest that during soil forming periods eolian dust accumulation was still substantial and hence loess deposition can be regarded as a nearly continuous process during the quaternary period in this study we compared the baoji grain size time series with the specmap marine isotope record with the objective of elucidating the dynamic linkage between changes in global ice volume and the winter monsoon circulation both records show good agreement at both time and frequency domains in particular the winter monsoon variations are also dominated by a 100 000 yr period over the past 800 000 yr it is thus inferred that direct local insolation forcing could be less important in driving the east asian winter monsoon variability and alternatively variations in glacial age boundary conditions may have played a key role in modulating and pacing its strength and timing

tropical cyclones in the southwest pacific spatial patterns and relationships to southern oscillation and sea surface temperature abstract an analysis of a 20 yr dataset of tropical cyclones in the southwest pacific has been made to determine the spatial patterns of cyclone occurrence and how these depend on the southern oscillation so and sea surface temperature a local measure of cyclone incidence is defined as the number of cyclones that enter into a 2 lat long square during some period eg within one season and this quantity is mapped for four southern oscillation index soi categories the maps show that the geographical distribution of cyclone incidence shifts eastward and northward during negative soi phases and vice versa the mean annual incidence for the whole region is 28 higher than average for our strongly negative so category and 16 below average for our near zero category to explore the roles of the so and local sst correlation analysis was applied to mean values of cyclone incidence for four subregions of 20 longitude width between 10 and 22 s markedly different soi sst responses were found on either s

seismicity induced by gas production i correlation of focal mechanisms and dome structure from august 1976 to june 1979 more than 220 seismic events were recorded by a 7 station network operating over an active gas field in france 120 earthquakes with magnitudes greater than 1 0 were selected for a detailed study in order to understand the seismic response to a decrease in the gas reservoir pressure of 50 mpa composite focal mechanisms were determined for these events we found that where preexisting fractures were known from well logs faults with the most favorable orientation were reactivated in the part of the gas field where no preexisting faults were known orientation of the fracture planes was close to the orientations of stratigraphic interfaces our kinematic model constrained by the distribution of the earthquakes and their focal mechanisms consists of the downward dropping of a block located close to the top of the gas field the main faults as defined by the spatial density of the seismic activity define the limits of this block the displacements observed along these faults can be either normal or reverse mechanism dependent on the preexisting orientation of each fault another important result is the evidence that the depletion of the gas reservoir exerts the major influence on local seismic displacements obscuring the effect of regional setting

the geochronology of the gorjanovic loess section in vukovar croatia abstract along the right bank of the danube river in croatia up to 30 m thick loess palaeosol sequences are exposed a detailed geochronological study was performed on the gorjanovic loess section at vukovar by the means of infrared stimulated luminescence irsl dating the section consists of loess intercalated by three palaeosols and a tephra layer fourteen samples were collected and dated using the elevated temperature post ir irsl protocol a modified single aliquot regenerative dose sar protocol for the equivalent dose de determination on fine grained polymineral material both the irsl signal at 50 c and the post ir irsl signal at 225 c were recorded fading tests were performed for both signals and the ages were fading corrected the loess palaeosol sequence can be correlated to the penultimate glacial last interglacial last glacial period mis6 mis2 an even older loess record at the site under study was previously described but is not exposed anymore owing to the embankment the fading corrected irsl and the fading corrected post ir irsl results are in excellent agreement the post ir irsl signal at 225 c shows less fading than the irsl signal at 50 c and can successfully be used for the dating of older loess

towards a revised chronostratigraphy of loess in austria with respect to key sections in the czech republic and in hungary abstract the stratigraphic ages of some well known and characteristic paleosols in austrian and hungarian loess sections have been questioned by several workers since the mid 1970s in particular a generally accepted correlation of austrian and hungarian loess stratigraphies with the well established czech loess stratigraphy has not been put forward this paper presents 41 new thermoluminescence tl dates and the first results from amino acid chronology of key sections in these areas the results are in agreement and suggest a new interregional correlation of loess paleosol sequences for loess older than the last interglacial quartz and feldspar inclusions yield more reliable tl ages than the polymineralic fine grain fraction

pleistocene climates in china dated by magnetic susceptibility the magnetic susceptibility of loess and interbedded soils in central china varies with the degree of pedogenesis and serves as a proxy measure of climate the concentration of magnetic minerals in the sediment is inversely proportional to sedimentation rates throughout the brunhes epoch susceptibility measurements combined with the reversal stratigraphy provide a time scale that is independent of astronomic chronology on this scale the susceptibility record closely parallels the oxygen isotope fluctuations in deep sea sediments suggesting a close interdependence of the chinese dust falls the volume of land based ice and global climate

austrian mis 3 2 loess palaeosol records key sites along a west east transect based on a w e transect through the northern loess regions of austria palaeoenvironmental studies were carried out in three loess palaeosol sequences gunderding krems wachtberg and stillfried b locus typicus to complement available results in the context of a multi methodological approach on the base of previously published datings our study concentrates on the mis 3 2 transition the results of detailed micromorphological investigations prove that palaeopedogenesis frost processes and sedimentation rates differ in their spatial occurrence in the loess belt of austria all three sequences are in line with the general trend of a reduced intensity of pedogenic and cryogenic features from western to south eastern europe which can be explained by lower atlantic moisture influence towards the east interstadial cambic horizons are well developed in the mis 3 sequence of western austria whereas the eastern loess profiles only show weak pedogenesis in all studied sequences frost processes were active during the upper mis 3 and mis 2 the studied mis 2 records are characterised by tundra soils with reductaquic horizons which is a clear sign for prolonged phases of permafrost on the spatial scale the sedimentation rate increases in the eastern loess regions and particularly the krems wachtberg sequence in the centre of the transect experienced an exceptionally high sedimentation rate and can thus be seen as one of the most important high resolution records for the mis 3 2 transition in european loess regions

humid glacials arid interglacials critical thoughts on pedogenesis and paleoclimate based on multi proxy analyses of the loess paleosol sequence crvenka northern serbia abstract loess paleosol sequences lps provide unique terrestrial archives for past environmental and climate changes the loess units are generally interpreted to reflect more arid conditions whereas paleosols are thought to document more humid conditions this paradigm may however deserve to be challenged in some regions because it does not take into account past changes in dust accumulation rates here we present a multi proxy sedimentological and geochemical characterization of the lps crvenka serbia spanning the last 140 ka commonly used analyses such as magnetic susceptibility organic carbon content grain size and weathering indices allow the quantification of the intensity of pedogenesis however loess accumulation rates were much higher during glacials than during interglacials so that it is not trivial to infer past rates of pedogenesis and related paleoclimate conditions novel proxies based for example on lipid biomarkers and their isotopic composition are not so directly affected by changes in loess accumulation rates and might provide interesting new insights long chain plant derived n alkanes in the lps crvenka suggest a minor but non negligible contribution of deciduous trees and shrubs c27 and c29 during mis 1 2 4 and 6 whereas grasses and herbs c31 and c33 dominate the alkane input during mis 3 and 5 this is in agreement with the notion that parts of southeast europe served as refugia for deciduous trees during glacials on the other hand edaphic conditions on the drought prone loess plateaus seem to have been more arid during mis 3 and 5 compound specific d analyses on the alkanes show only little changes on glacial interglacial timescale when compared with the isotopic enrichment of the mediterranean sea during the last glacial this likely indicates a complex combination of reduced temperatures increased rainfall reduced evapotranspiration and more advection of north atlantic moisture although disentangling these factors is difficult interpretation in terms of humid glacials and more arid interglacials seems to be supported also by other novel lipid biomarkers so called gdgts glycerol dialkyl glycerol tetraethers

the late quaternary environmental history of batorliget n e hungary abstract a sedimentary sequence extending back into the last glacial has been obtained from batorliget marsh in n e hungary reconstruction of the environmental history of the region using the techniques of pollen analysis molluscan analysis and geochemistry has revealed an important late quaternary refugium during the last glacial a refugium for temperate flora and fauna existed within a landscape dominated by coniferous forest predominantly made up of pinus and picea the lateglacial postglacial transition at 10 000 yr b p resulted in a dramatic shift from coniferous but also including betula woodland to deciduous woodland following the lateglacial postglacial transition a highly diverse woodland became established in the early postglacial accompanied by an equally diverse molluscan assemblage this diversity remained throughout the early postglacial although the types present within the woodland changed a number of times at c 7000 yr b p anthropogenic disturbance resulted in the destruction of the mixed forest and the development of agricultural land the importance of this region as a refugial area both in the lateglacial and early postglacial is discussed and the influence that it had on the postglacial development of the fauna and flora of northeastern hungary is reviewed

pleistocene environmental dynamics recorded in the loess of the middle and lower danube basin abstract the substantial loess deposits of the middle and lower danube basin in southeastern europe represent one of the thickest and most comprehensive terrestrial palaeoenvironmental records on the continent yet are also the least well understood environmental conditions over the last million years have resulted in relatively continuous deposits uninterrupted by glaciation and tundra conditions which nevertheless reflect oscillations between relatively warm humid interglacial and cold dry glacial intervals this relative environmental stability may have proven important for hominins migrating into and through the region the loess stratigraphy comprises distinct loess paleosol sequences reflecting glacial interglacial phases which can be quantified for intensity using environmental magnetism and geochemistry these phases are emphasised by variations in vegetation and malacofauna which respond to climatic change the loess deposits demonstrate broadly similar sedimentological characteristics across the basin danubian loess deposits initiated in response to the tectonic formation of the pannonian basin retreat of the large palaeolakes and increased sediment supply from the danube the period from 1 ma 500 ka mis 27 13 was characterised by alternating loess deposition and pedogenesis during glacial and interglacial periods respectively in response to relatively humid forested conditions this period represents the opening of the danube corridor and provides the backdrop for initial hominin arrival into europe after 500 ka and particularly after mis 9 loess accumulation rates increased in response to relatively more steppic arid environments mis 9 and 13 15 were the most humid phases of the last 600 ky the mis 5 interglacial period was the warmest and relatively most humid period preceding the holocene and was followed by substantially increased loess accumulation during mis 4 which may be linked to north atlantic circulation the complexity of the mis 3 interstadial paleosol suggests that conditions were not uniformly warm and wet during this time mis 3 corresponds with the first arrival of anatomically modern humans to europe the last glacial maximum and younger dryas of mis 2 were characterised by substantially increased loess accumulation indicating cold steppe environments most likely influenced by the north atlantic although conditions were sufficiently mild that the region acted as a refugium for thermophilic biota as may also have been the case for most of the pleistocene glacial cycles the holocene soil represents relatively wamer and more humid conditions corresponding to the current interglacial

amino acid geochronology applied to the correlation and dating of central european loess deposits abstract numerous localities in the czech republic slovakia and austria have been sampled for fossil gastropod shells for the purpose of an aminostratigraphic evaluation of loess sequences in all three regions alloisoleucine isoleucine aile ile ratios are observed to be significantly higher in shells from loess deposited during the penultimate glacial period cycle c relative to samples from loess of the last glaciation cycle b the difference in aile ile ratio reflects both difference in age of the samples plus the impact on the older samples of the relatively high effective temperature of the last interglacial period amino acid data support the previous correlation suggested between pk ii iii in the czech republic and slovakia and the stillfried a in austria samples have also been recovered from older loess units and previously published correlations within the czech and slovak republics are tested aiie ile ratios appear to distinguish between samples from loess of the last four glacial cycles beyond cycle e 18o stages 10 and 11 the increase in alle ile ratio is relatively small from cycle to cycle in addition shells tend to be poorly preserved and are absent at many localities nevertheless amino acid geochronology offers a means of resolving ages of loess units in the critical time period that is beyond the range of radiocarbon and thermoluminescence methods but post dates the brunhes matuyama paleomagnetic reversal

spatio temporal seismicity patterns using mutual information application to southern iberian peninsula spain earthquakes abstract a quantitative method to characterize the spatio temporal evolution of the seismic activity of a region for a given time interval is proposed in this paper the epicentral region is divided in equal area parallelograms that we call cells a probability p i is assign to every cell depending on its seismic activity level the evolution of the mutual information based on these probabilities allows us to fit the optimal value for p i s the analysis results show that is possible to monitor the change of seismic activity quantitatively we show that a propagation model based on cross template model ct model give us a criteria whether or not an area whose size is determined by the model mathematically is going to be considered seismically activated in a period of time whose value is also the result of the application of the method our method is applied to the data of southern iberian peninsula seismicity including more than 10 000 earthquakes data available from the andalusian seismic network is used from 1985 to 1995

the late quaternary loess record of tokaj hungary reconstructing palaeoenvironment vegetation and climate using stable c and n isotopes and biomarkers abstract large areas of southeast europe are covered by pleistocene loess deposits with interbedded palaeosol layers reflecting interglacials or stadials these loess palaeosol sequences are valuable terrestrial archives for continuous palaeoclimatic and palaeoenvironmental information in recent years the traditional paradigm of treeless full glacial palaeoenvironments has increasingly been called into question as there is palynological anthracological and malacological evidence for the continuous presence of trees from loess palaeosol sequences in the carpathian basin this paper aims at contributing to this discussion by applying biogeochemical geophysical and sedimentological methods to a late quaternary loess palaeosol profile at tokaj ne hungary previous studies at the same location have focused on molluscs and charcoal while this study concentrated on stable c and n isotopes and lipid biomarkers long chain n alkanes c 23 c 33 which form major constituents of plant leaf waxes have successfully been used as biomarkers over the last years and allow for a reconstruction of palaeovegetation based on the differentiation of grassland vs shrubs and trees stable carbon isotopes were used to further differentiate between c 3 and c 4 palaeovegetation and stable n isotopes to reconstruct the n cycle and climatic variations magnetic susceptibility ms organic carbon and grain size distribution which may serve as proxies for e g the intensity of pedegenesis weathering and palaeowind strength were measured to complement the biogeochemical results and to establish a pedo and biostratigraphy although the results do not agree in every detail with previous studies there are surprising matches and similarities in the data alkane and stable n isotopic data indicate that pedogenesis occurred under productive fertile steppe grasslands probably in an intensified seasonal climate and during reduced sedimentation two short treeless steppe periods were found between 26 and 12 ka bp however periods characterised by a cooler climate in which trees and shrubs expanded were also found this interpretation is also supported by previous mollusc data that provide evidence for several periods of favourable conditions for tree growth

loess rock sediment or soil what is missing for its definition abstract loess is commonly defined as an accumulation of windblown silt however the complex mechanisms that are responsible for most of the structural characteristics of loess require a more precise explanation the common definition of loess ignores a set of processes that start during and after the subaerial deposition of silt the term loessification has been used by a number of authors to refer to the quasi pedogenic quasi diagenetic processes that result in the typical aggregation of loess however these mechanisms are rarely described in detail depending on the researcher s background loess is classified as sediment soil or rock this review gives an overview on loess definitions through time and evaluates the main concepts related to loess formation several gaps of knowledge are identified that require a number of specific studies related to different aspects of loess formation in various environments we propose to 1 differentiate primary loessification which initializes the formation of loess structure from secondary loessification which takes place subsequently and 2 define loess like sediments as deposits that experienced loessification but were not transported aeolian mainly aeolian processes and loessification are of equal importance to define loess

palaeoclimatic implications of the magnetic record from loess palaeosol sequence viatovo ne bulgaria summary loess palaeosol deposits in the lower danube area represent the southeastern edge of the loess cover in europe detailed rock magnetic investigations of the loess palaeosol sequence in viatovo in ne bulgaria reveal that magnetite and maghemite of very fine superparamagnetic grain size are responsible for the magnetic enhancement of palaeosol units a detailed palaeoclimatic record is obtained through high resolution measurements of magnetic susceptibility frequency dependent magnetic susceptibility and caco3 content magnetic proxies indicate a more warm and humid climate during the development of the older palaeosol units s4 s6

long term terrestrial records of the middle danubian basin abstract in eastern central europe in the middle danube basin loess and loess like deposits cover various morphotectonic levels in a total area of ca 150 000 km 2 basin types of various elevations and sizes are predominant under different geomorphological or morphotectonic conditions over an identical time interval the variation in the rate of basin subsidence produces various litho and chronostratigraphical sequences the subaerial sequence of basins affected by prolonged subsidence in the quaternary is subdivided by paleosols of larger number than the loess paleosol sequence of basins elevated plateaus or watersheds which underwent more moderate subsidence during the quaternary loess paleosol sand sequences on pediments 100 150 m above sea level in the loess paleosol sand sequences of 50 100 m thickness ca 12 loess 10 sand and silt layers and 20 30 paleosols are present the age of these profiles with hiatuses is pliocene pleistocene loess paleosol sand sequences on alluvial fans and terraces 10 100 m relative heights the loess sequence is 40 60 m thick and subdivided by 10 12 loess horizons 10 12 paleosols and 5 or 6 sand layers ltr pliocene pleistocene subaerial basin sediment locally of 500 1500 m thickness the surface of the basin is a flood plain at 90 100 m above sea level in the basin sediments the number of paleosols may reach one hundred in several boreholes there are 6 12 red soils or red clays between 600 and 1000 m 12 16 intercalated sand layers are observed the age of this almost complete sequence is 5 2 5 4 ma bp in the most intensively subsiding basins sedimentation was almost continuous during the pliocene ca 50 60 and in the pleistocene ca 50 soils developed in contrast on the non subsiding foothills only 20 30 soils formed during the pliocene and pleistocene and several gaps are detected in the sequence

geochemical characterization and origin of southeastern and eastern european loesses serbia romania ukraine abstract the loess paleosol sections of batajnica stari slankamen serbia mircea voda romania and stary kaydaky ukraine were geochemically characterized based on discriminant analysis of major and trace elements the ratios of al ti fe ti and al fe the a cn k ternary plot and element enrichment depletion relative to the average composition of the upper continental crust the origin of the loess material in the southern pannonian basin vojvodina the lower danube basin dobrudja and the dnieper area was evaluated by comparison with the representative element composition of possible source areas and by considering the geomorphodynamic setting also the background values of the initial magnetic susceptibility of the loesses were taken into account for the lower danube basin dobrudja and the ukraine paleowind direction was reconstructed based on the geographic distribution of sandy soil texture and dunes related to river systems finally loesses were evaluated as possible samples of the average upper continental crust our results show that danube and dnieper loess areas can be clearly distinguished the former reveal higher al and fe contents the latter higher si zr hf content and indications of effective mineral and grain size sorting we can confirm that vojvodina loess originated from danube alluvial material and loess of the dnieper area from glaciofluvial sediments of the fennoscandinavian ice sheet the dobrudja loess derived also predominantly from danube alluvium but shows significant contribution of a second loess source probably the glaciofluvial sediments of the ukraine this was forced by northerly katabatic winds from the fennoscandinavian ice sheet whereas wnw winds prevailed in the western walachian plain the studied loesses reflect the average composition of the upper continental crust yet biases exist due to selective mineral element enrichment and depletion in the course of previous sedimentary recycling phases respectively material of all studied loess deposits seems to derive originally from sedimentary rocks

fracture mechanical behavior of red sandstone containing a single fissure and two parallel fissures after exposure to different high temperature treatments it is well known to us that the stability and safety of deep underground mining excavations and nuclear waste depositories rely on accurate knowledge of the physical and mechanical properties of representative rocks under the action of high temperature zhang et al in int j plast 34 93 113 2012

a seismotectonic analysis of the anza seismic gap san jacinto fault zone southern california small earthquake epicenters near the anza seismic gap define a 20 km quiescent segment of fault bounded to the northwest and southeast by areas of relatively high seismicity recent moderate earthquakes on and near the san jacinto fault in the gap and their relatively depressed aftershock activity indicate that the fault is seismogenic and highly stressed but locked by some mechanism the locked nature of the fault may be due to relatively high compressive stress normal to the fault resulting from the convergent geometries of the local active discontinuous faults and the oblique orientation of the regional maximum compressive stress strain is not being relieved by aseismic fault creep a swarm of small earthquakes in the crustal block 13 km southwest of the anza gap beneath the cahuilla valley recently released stress in an area which was previously highly active before the 1918 m 6 8 and 1937 m l 6 0 earthquakes the occurrence of these periods of increased seismicity near cahuilla in the years immediately before the nearby closer than 35 km large earthquakes and the recent swarm suggest that the ground beneath cahuilla may be acting as a stress meter signaling the presence of high stresses before large local earthquakes the length of the quiescent fault segment suggests potential for about an m 6 5 earthquake if the entire segment ruptures at once

franz ritter von hauer s work and one of the first loess map of central europe abstract franz ritter von hauer was the second director of the geological survey in vienna 1866 1885 the primary research of von hauer was devoted chiefly to the evolutionary history of cephalopods and geological mapping among several investigations of cephalopods of the triassic and jurassic formations of the alpine regions he recognized and discovered 89 species and established the middle and late triassic stratigraphical units of deep shelf environments the hallstadt facies one of his main contributions to quaternary science was the geology textbook of the former austro hungarian monarchy which provided a resource to access recent developments in geology and notably loess research to many scientists besides the staff from the geological survey von hauer involved numerous local well recognized experts and organized regional centres for geological investigations this well managed and effective work resulted in a great number of publications many of which were the reports published by the geological survey the general geological map of the austro hungarian monarchy was one of the most comprehensive and complete geological map of central europe during that period of time it was presented in cologne 1865 and from 1867 until 1884 ran to four editions the quaternary formations were presented in two groups pleistocene and holocene formations the pleistocene formations identified as dilluvial formations and were represented predominantly as gravels and sand and also as loess the holocene formations were described as alluvial formations they were mapped as peat lime tuff quicksand and other formations named only as alluvial formations loess was mentioned exclusively as a pleistocene dilluvial formation the distribution of loess was clearly outlined due to the development of the science at that time the term loess was not clearly defined and as such at some places loess like sediments such as colluvial were also mapped as loess nevertheless it was one of the first maps which documented the extent of loess deposits and including the regions of lower austria with vienna basin bohemia and moravia the carpathian basin parts of the polish lowland and transylvania

loess stratigraphy in central china abstract the loess deposits in central china record world wide climate changes of the last 2 5 ma numerous climatic oscillations are marked by alternating loess and soil units with continuous coverage of the matuyama and brunhes epochs magnetic susceptibility of the deposits correlates closely with the oxygen isotope record of the deep sea sediments and provides an independent measure of climate and time the key marker bed of the chinese loess sequence is the paleosol s5 the time equivalent of the mid brunhes oxygen isotope stages 13 14 and 15 it marks a prolonged interval of warm humid climate lasting from approximately 615 to 470 thousand years ago several episodes of river downcutting coincide with deposition of the exceptionally thick loess units l1 oceanic oxygen isotope stages 2 to 4 l2 stage 6 l5 stage 12 l6 stage 16 l9 stage 22 l15 stage 38 about 1 15 ma and ws4 about 2 3 ma these erosional events are interpreted as a result of episodic uplift of the loess plateau the deposition of the earliest loess layers between 2 5 and 2 3 ma ago marks a first order shift from warm and humid environments toward harsh continental steppes comparable to those of the middle and late pleistocene little if any lithologic or paleontologic changes were noted within or above the olduvai magnetozone so that the proposed plio pleistocene boundary at approximately 1 65 ma has no lithostratigraphic and biostratigraphic representation in the chinese loess series comparison with the deep sea drilling program core 552a in the north atlantic and with the santerno river section near bologna shows that the occurrence of the earliest loess in china coincides with the timing of the first significant ice rafting in the north atlantic and with the appearance of cold water foraminifers in the marine deposits of northern italy an extension of the stage system of the oxygen isotope signal extended back to the gauss matuyama boundary is proposed

summer monsoon variations over the last 1 2 ma from the weathering of loess soil sequences in china the loess soil sequence in northern china contains a near continuous record of quaternary paleoclimate magnetic susceptibility and grain size have so far been the only proxies available to address the long term changes of the east asian paleomonsoon extending back to more than one million years in this study the ratio of cbd citrate bicarbonate dithionite extractable free fe2o3 fed a measure of iron liberated by chemical weathering versus the total fe2o3 available fet was measured on samples at 10 cm intervals taken from two loess sections deposited over the last 1 2 ma variations of this index are highly consistent with other pedological indicators but in addition provide a quantitative measurement of the degree of pedogenesis in the loess plateau since chemical weathering in the region mainly depends upon summer precipitation and temperature weathering intensity primarily reflects changes in the east asian summer monsoon the new proxy has been used to document a series of summer monsoon changes of global significance which are not necessarily recorded by magnetic susceptibility

palaeoenvironment and geoconservation of mammoths from the nosak loess palaeosol sequence drmno northeastern serbia initial results and perspectives a quaternary site at drmno comprising of middle and late pleistocene loess palaeosol sequences near kostolac northeast serbia attracted attention from the general public and scientists when several steppe mammoth and other mammal skeletons from middle pleistocene fluvial deposits were discovered in 2009 and 2012 this paper presents the combination of malacological and enviromagnetic analyses preliminary luminescence dating litho pedostratigraphic and palaeo relief investigations that were applied to the nosak loess palaeosol sequence for the 2012 findings the results confirm and emphasize the antiquity of the sediments preserved in the nosak section and demonstrate the significance of the detailed and relatively complete palaeoenvironmental record they contain these discoveries can significantly contribute to setting the background towards an improved understanding of the evolution of mammoths on the european continent

tectonic stress orientation and the seismic regime of a single fault abstract the seismic regime of tectonic faults was studied by the method of physical modelling this method is based on the assumption that the physical processes in actual seismo active fault zones can be scaled in laboratory conditions the results of our laboratory experiments on plate models proved the great importance of tectonic stress orientation on the seismic regime of tectonic faults changes in the fault inclination led to distinct changes both in the recurrence time intervals between individual seismic events and in the amount of seismic energy released for some fault inclinations the seismic activity of faults vanished altogether only a limited zone in the fault plane was found to participate in the process of seismic energy release the extent of this so called seismo active zone depends not only on the contact conditions but also on the value of the acting load and on the fault inclination this presumption is supported by the fact that for each inclination there exists an upper limit to the seismic energy that can be released in one seismic event

middle and late pleistocene loess sequences at batajnica vojvodina serbia abstract loess sequences in the vojvodina region northern serbia reveal a continuous record of paleoclimatic variations during the middle and late pleistocene the most detailed stratigraphic information comes from remarkable exposures on the cliffs of the right danube bank from vukovar to belgrade the batajnica loess section has been recognized as one of the most complete middle and late pleistocene records in this region a more than 40 m thick loess paleosol succession represents environmental transition from relative thin loess layers and rubified soils in lower part of profile to thick loess and fossil chernozems characterizing the last three glacial interglacial cycles the proposed stratigraphic model is based on a detailed magnetic susceptibility ms record which is related to the deep sea isotope stratigraphy and on correlation with other eurasian loess records using the distinct ms pattern of selected loess paleosol couplets this new stratigraphic model suggests serious revision of previous chronological interpretations ms as function of depth shows a well known pattern of low values in loess and high values in paleosols indicating strong enhancement of magnetic minerals during soil formation with the exception of the recent soil v s0 which is strongly contaminated by archaeological artifacts the third paleosol v s3 reveals the highest values in ms and a very distinct double peak the rock magnetic signal at batajnica resembles the typical pattern of the enviromagnetic records determined from other eurasian loess sites the paleopedological interpretations rubification index values and rock magnetic record at batajnica yield valuable data for the reconstruction of paleoclimatic fluctuations for the last 5 glacial interglacial cycles at least moreover the record provides an important link between the classical central european loess sites and the central asian and chinese loess provinces

environmental dynamics and luminescence chronology from the orlovat loess palaeosol sequence vojvodina northern serbia the carpathian basin contains some of the best preserved loess deposits in europe including some of the continent s longest and best resolved climate records large areas of the basin have been intensively investigated in recent years although deposits in the east remain largely unstudied despite considerable regional variation in climate records here we discuss the sedimentary record exposed in the orlovat brickyard using detailed litho and pedo stratigraphic enviromagnetic parameters and luminescence dating the results show an atypical late pleistocene succession for the carpathian basin notably the normally widespread pedocomplex v l1s1 is missing this contrasts with other parts of the sequence which appear highly resolved such as the thicker pedocomplex v s1 and the detailed transitions between modern pedocomplexes v s0 and the last glacial loess unit v l1 the luminescence chronology demonstrates a lack of intensive pedogenesis during the early holocene and raises an important general question about the beginning of holocene soil formation in the region the later holocene soil formation adds to a growing body of evidence that suggests more complex terrestrial responses of climate to global climate change this evidence weakens the validity of previously generalized direct stratigraphic correlations between regional terrestrial environmental archives and global marine and ice core records copyright 2014 john wiley sons ltd

an introduction to the middle and upper pleistocene loess paleosol sequence at ruma brickyard vojvodina serbia abstract six loess units and five paleosols are preserved in the 20 m thick exposure of middle and late pleistocene sediments at ruma brickyard vojvodina serbia amino acid geochronology provides stratigraphic correlations between loess paleosol units sl l1 s1 sl l2 s2 sl l3 s3 and sl l4 at ruma with loess of glacial cycles b c and d and e respectively at other central and southeastern european localities the profile represents one of the best potential sections in the region for reconstructing detailed paleoclimates and paleoenvironments of the last ca 350 000 yr initial sedimentological magnetic and malacological evidence indicate many episodes of drier conditions in the region than in other parts of central and southeastern europe during the later part of the middle and late pleistocene

the campanian ignimbrite y5 tephra layer a regional stratigraphic marker for isotope stage 3 deposits in the lower danube region romania a number of volcanic ash layers embedded in pleistocene loess and fluvial deposits of the lower jiu and olt valleys in south western romania have been analyzed for glass chemical compositions and general chronological relations the wds epma chemical analyses document remarkably similar major and minor element compositions at the four investigated sites and total alkali silica diagrams ascribe these volcanic ashes a phonolite to trachyte affinity a comparison with the quaternary carpathian volcanism chemical data refutes this volcanic field as the primary source even though earlier works have tentatively taken some of these volcanic ashes as evidence of volcanic activity in this particular field instead the chemical data suggest an origin in the campi flegrei volcanic province in italy and a comparison with chemical data from proximal and distal outcrops of the campanian ignimbrite y5 tephra confirm that the ash layers presented here are distal occurrences of this widespread tephra layer the campanian ignimbrite y5 tephra is the product of one of the largest late quaternary explosive events in the mediterranean and is consistently dated elsewhere to about 39 40 ka it is one of the most important chronologic stratigraphic markers of western eurasia that provide an independent basis for establishing age depth relationships for the embedding deposits optical luminescence age estimates obtained at two of the investigated sites further confirm that these volcanic ash occurrences represent a regionally synchronous depositional event around 40 ka these results highlight the important role that the campanian ignimbrite y5 tephra could play as marker horizon at sub continental scale providing that more potential tephra locations such as these from the pleistocene sedimentary deposits in the lower danube region are chemically and chronologically constrained

magnetic properties of loess grain size fractions from the section at paks hungary abstract the approximately 50 m thick loess palaeosol sequence at paks brickyard hungary was deposited largely during the brunhes normal polarity chron and its magnetic properties resemble those of similar sections in europe central asia and china in order to get information on the grain size dependence of some of the magnetic parameters two loess and two palaeosol samples were separated into a number of grain size fractions the separation method employs consecutive sedimentation and centrifugation steps performed on bulk samples suspended in water and diluted with calgon ten grain size fractions were obtained ranging from 50 m down to 10 nm several magnetic parameters of the different grain size fractions have been measured at room temperature low field susceptibility hysteresis parameters and at low temperature susceptibility and thermoremanent magnetisation they show a strong grain size dependence for the ferromagnetic minerals low temperature measurements allow discrimination of the paramagnetic vs the ferromagnetic signal and give information on the grain size distribution of the very fine ferromagnetic minerals and on the mineral types carrying the magnetic signal strong relationships between weathering processes destruction of paramagnetic minerals and possibly iron hydroxides and enhancement of the ferromagnetic signal are observed

seismic regime of a single fault model a special experimental technique enabled us to study in detail seismic events on a fault model in a uniaxial stress field the recording system used made it possible to investigate the radiation pattern for all the events observed including the precise determination of the dislocation origin

luminescence and amino acid racemization chronology of the loess paleosol sequence at suttő hungary abstract the loess paleosol sequences in hungary provide an excellent upper pleistocene climate archive of the carpathian basin loess deposits up to 20 m thick cover the sutt travertine complex located in the very northern part of hungary next to the right bank of the danube river the loess is intercalated with two weakly developed greyish horizons two thinner brownish steppe like soils and a pedocomplex including a reddish brown clay enriched horizon covered by a chernozem like paleosol infrared optically stimulated luminescence irsl dating was applied on polymineral fine grain material to determine the depositional age of the loess the uppermost loess yields irsl age estimates ranging from 15 to 40 ka the loess on top of the pedocomplex yields irsl age estimates ranging from 48 to 60 ka the pedocomplex most likely correlates with the marine oxygen isotope stage mis 5 interglacial period the loess from below the pedocomplex was deposited during the penultimate glaciation as evidenced by amino acid racemization aar results further independent age control is provided by radiocarbon dating for the upper part of the profile and by uranium series 230th 234u ages correlating the travertine below the loess with mis 7 8 the magnetic susceptibility record through the sequence shows a strong correlation with the loess layers and soil horizons

dust deposition and climate in the carpathian basin over an independently dated last glacial interglacial cycle dust deposition and climate in the carpathian basin over an independently dated last glacial interglacial cycle

high resolution record of the environmental response to climatic variations during the last interglacial glacial cycle in central europe the loess palaeosol sequence of dolni věstonice czech republic abstract high resolution multidisciplinary investigation of key european loess palaeosols profiles have demonstrated that loess sequences result from rapid and cyclic aeolian sedimentation which is reflected in variations of loess grain size indexes and correlated with greenland ice core dust records this correlation suggests a global connection between north atlantic and west european air masses herein we present a revised stratigraphy and a continuous high resolution record of grain size magnetic susceptibility and organic carbon 13c of the famous of dolni vestonice dv loess sequence in the moravian region of the czech republic a new set of quartz osl ages provides a reliable and accurate chronology of the sequence s main pedosedimentary events the grain size record shows strongly contrasting variations with numerous abrupt coarse grained events especially in the upper part of the sequence between ca 20 30 ka this time period is also characterised by a progressive coarsening of the loess deposits as already observed in other western european sequences the base of the dv sequence exhibits an exceptionally well preserved soil complex composed of three chernozem soil horizons and 5 aeolian silt layers marker silts this complex is at present the most complete record of environmental variations and dust deposition in the european loess belt for the weichselian early glacial period spanning about 110 to 70 ka allowing correlations with various global palaeoclimatic records osl ages combined with sedimentological and palaeopedological observations lead to the conclusion that this soil complex recorded all of the main climatic events expressed in the north grip record from greenland interstadials gis 25 to 19

theory of time dependent rupture in the earth at a velocity x which is a well defined function of k this propagation is stable and quasi static and is referred to as subcritical crack growth we shall use the terms stable quasistatic and subcritical to mean propagation at velocities much less than the sonic velocities of the medium this behavior results from stress induced corrosion at the crack tip the principal corrodent for the present application being h20 this behavior has been firmly established in the laboratory for mode i tensile cracks in a wide variety of materials ineluding silicates and silicate glasses see cholz 1968a 1972a martin 1972 wiederhorn and bolz 1970 atkinson 1979 lawn and wilshaw 1975 knott 1973 the form of the relationship between k and x does not vary significantly with the material only the parameters in the law vary as an example we show in figure 1 data on subcritical crack growth in quartz after atkinson 1979 the empirical relationship is found to take the form

micromorphology and genesis of paleosols in the luochuan loess section china pedostratigraphic and environmental implications the loess paleosol sequence in the well known potou section near luochuan covers the entire pleistocene back to 2 5 ma in a much more complete sequence than any known from europe or north america to deduce a record of the pleistocene climatic history an understanding of the genesis of the paleosols is important main diagnostic features normally observable in surface soils have disappeared in the case of fossil soils therefore micromorphology is of outstanding importance because it enables the reconstruction of original properties and polygenetic soil development especially in pedocomplexes the upper part of the loess paleosol sequence can well be compared with the 18o record shown in the specmap curve of the brunhes epoch although the sequence of paleosols shows partly an even more detailed record of cold and warm stages and allows more specific informations regarding the paleoclimate of the interglacial periods cf fig 2 the last four paleosols represented by the s1 pedocomplex the upper part of the s2 and the s3 are genetically well comparable with the natural holocene soil indicating a similar climate with a tall grass steppe vegetation the s6 is a steppe soil also whereas the five soils of the s4 the s5 complex and the s7 are forest soils indicating more moist and partly warmer interglaciations than the holocene the loess paleosol sequence of the matuyama epoch seems to give more paleoclimatic informations than the deep sea cores known so far the lishi loess below the b m boundary down to 84 m in the section contains two more soils s11 and s13 which are developed under steppe vegetation in interglaciations similar to the present one and four forest soils the s8 complex the upper soil of the s9 and the s10 indicating again more moist interglaciations than the holocene most of the numerous soils in the wusheng loess are probably formed synsedimentarily as alternation of soil formation and addition of loess the red clay at the basis consists of four intensively developed but truncated paleosols the parent material of at least the lower part must be regarded as pliocene loess