impact melt breccia and surrounding regolith measured by chang e 4 rover abstract chang e 4 rover discovered a dark greenish and glistening impact melt breccia in a crater during its traverse on the floor of von karman crater within the south pole aitken spa basin on the lunar farside the discovered breccia being 52 16 cm resembles the lunar impact melt breccia samples 15466 and 70019 that returned by the apollo missions it was formed by impact generated welding cementing and agglutinating of lunar regolith and breccia clods surrounds the breccia hosting crater were crushed into regolith powders by the rover s wheels indicating the regolith may be compacted slightly and becomes blocky and friable relative mineral fractions are estimated from the in situ measured spectra by a hapke model based unmixing algorithm unmixing reveals that plagioclase plg 45 6 is dominant in the regolith followed by almost equal fractions of pyroxene pyx 7 1 and olivine ol 6 2 indicating the regolith is likely related to noritic rocks the regolith measured by chang e 4 rover was actually a highly mixture of multiple sources with ejecta from finsen crater being primary and possible contributions from alder crater finsen and alder craters are on the margin of the proposed impact melt pool produced by the spa basin forming event therefore the ultimate source of the regolith might originate from a differentiated melt pool or from a suite of igneous rocks

characterization of an internal slope movement structure by hydrogeophysical surveying a hydrogeophysical study was carried out by a water controlled injection within a landslide situated on an active part of the la clapiere landslide foot alpes maritimes france coupling of both real time geophysical and hydrological follow ups allowed the representation and quantification of the surface water drainage in space and time within the slipped mass thus 30 of the injected water is quickly drained by a complex slipping surface meanly situated at 10 m depth the transit time between injection and outflow of the water allowed an overloading of about 10 m3 i e 10 tons comparable with classical rain events in the area this weight and the associated interstitial pressures increase have not led to any movements asking for the origin of the water volumes which could induce destabilizations this experiment enabled an accurate redefinition of the internal slope structure and the understanding of the dynamics of the slipped mass with a surface hydraulic request

on the use of combined geophysical methods to assess water content and water conductivity of near surface formations abstract we propose to deepen the interpretation of combined geophysical methods georadar seismic and electric to assess physical properties characterizing the near surface porous formations especially the influence of water velocity analysis of multioffset georadar data are used together with seismic methods to estimate lateral and vertical ground water fluctuations this enables us to identify transitions from non saturated to fully saturated porous layers with certainty furthermore the accurate knowledge of seismic velocities helps to estimate the porosity of the ground water formations finally we show how the radar technique may be useful in solving the problem of trade off between bulk resistivity which is deduced from electrical measurements and that of water ionic conductivity and water content these theoretical considerations are illustrated using various measurements conducted at the same test site our interpretation is compared with a few laboratory measurements on water and soil samples this study displays the impact of combined geophysical approaches for providing models of water and ionic transfers down to a depth of several metres

mineralogical records of early planetary processes on the howardite eucrite diogenite parent body with reference to vesta abstract mineralogical information recovered from the howardite eucrite diogenite hed meteorites was employed to reconstruct the history of the parent body and relate it to 4 vesta these interpreted crustal evolution processes were then compared to the expected geological features on the surface of a likely proto planet 4 vesta the original crustal materials of the hed parent body were preserved as mineral grains and lithic clasts but in many eucrites fe mg ratios in pyroxenes were homogenized by diffusion after crystallization the crystallization trend of the protocrust has been deciphered by 1 examining monomict and crystalline samples and using their mineralogical and chemical information to formulate a sequence of crystallization and cooling trends and by 2 reconstructing the original crust prior to cratering events from lithic clasts and mineral fragments in polymict breccias such as howardites and polymict eucrites mineral components are identical both in the individual hed and in polymict breccias and no remnants of primitive materials were preserved in the polymict breccias a layered crust model reconstructed from such breccias consists of an upper crust with extrusive lava like eucrites that have been brecciated and metamorphosed diogenite mantle and cumulate eucrites of varying thickness between them this model can be used to explain the surface geological features of vesta observed from the hubble space telescope a large crater with diogenitic orthopyroxene at the crater floor is consistent with the deepest diogenitic layer of the layered crust model and an underlying olivine layer is expected from early crystallized olivine in the crystal fractionation model the old terrain of eucritic surface materials of vesta can be howardites polymict eucrites or regolith like eucrites produced from eucrites extruded and impacted on the surface partial melting models of eucrites seem to be favored by the rare earth element ree chemistry and experimental studies unfortunately partial melting models have not demonstrated how the hed parent body is converted to a layered crust without producing any metamorphosed primitive material in the layered crust the origin of cumulate eucrites with systematic variation of textures and chemistries of pyroxene can be explained by the layered crust model with excavation and mixing of trapped liquid discovery of basaltic materials with na rich plagioclase and augite in iron meteorites which are the products of partial melting suggests that eucrites may be unique to a body that underwent large scale differentiation and metamorphism

seismic prospecting of a slope affected by deep seated gravitational slope deformation the lago sackung calabria italy abstract in this study seismic reflection and refraction were used to study the sackung of lago calabria italy the seismic track is roughly 1200 m long seismic reflection analysis has seldom been used to study mass movements structurally landslides tend to be extremely complex and the landslide body is not a good medium for seismic waves because of dispersion and noise however through the use of recent sophisticated software it has become possible for seismic reflection to obtain good results in this case study a package called seistrex 3 was used by means of static and topographic corrections enhanced by filtering and migration a seismic profile with good resolution of the geometry of layers and faults to depths of 100 400 m was obtained this study shows that seismic reflection is more useful than seismic refraction for examining the internal structure of a landslide

geophysical investigations of large landslides in the carnic region of southern austria abstract the area under investigation for the past two decades is in the vicinity of the gailtal lineament which is the most dominant tectonic feature of the eastern alps of southern austria an area of about 8 km2 is in a state of constant instability as documented by movement of road tracks of several centimetres per year geotechnical and surveying techniques have been used to measure these movements in the past but without solving the problem of the mechanism of these failure processes geophysical methods seismic refraction geoelectrics and electromagnetics were applied in order to determine the validity of one of the discussed movement models in situ velocity measurements were used to identify different lithologies beneath surficial talus deposits the thickness of these talus deposits of about 4 30 m found by seismic refraction clearly demonstrates that huge blocks i e more or less undisturbed lithologic units within the talus debris are in close contact with the basement this basement which shows lower seismic velocities in different parts combined with low electric resistivities is obviously strongly disturbed by different failure surfaces the different gliding velocity of the blocks and the talus debris deposits leads to a geological model in which huge rock blocks move slowly in relation to the disintegrating basement whereas the talus debris deposits move over the surface of these blocks at a higher velocity the interpretation of these landslide studies is not a straightforward analysis it is a complex problem with a complex solution including all information from geotechnical geophysical and surveying investigations

petrologic insights from the spectra of the unbrecciated eucrites implications for vesta and basaltic asteroids we investigate the relationship between the petrology and visible near infrared spectra of the unbrecciated eucrites and synthetic pyroxene plagioclase mixtures to determine how spectra obtained by the dawn mission could distinguish between several models that have been suggested for the petrogenesis of vesta s crust e g partial melting and magma ocean here we study the spectra of petrologically characterized unbrecciated eucrites to establish spectral observables which can be used to yield mineral abundances and compositions consistent with petrologic observations no information about plagioclase could be extracted from the eucrite spectra in contrast pyroxene dominates the spectra of the eucrites and absorption band modeling provides a good estimate of the relative proportions of low and high ca pyroxene present cr is a compatible element in eucrite pyroxene and is enriched in samples from primitive melts an absorption at 0 6 lm resulting from cr 3 in the pyroxene structure can be used to distinguish these primitive eucrites the spectral differences present among the eucrites may allow dawn to distinguish between the two main competing models proposed for the petrogenesis of vesta magma ocean and partial melting these models predict different crustal structures and scales of heterogeneity which can be observed spectrally the formation of eucrite allan hills alh a81001 which is primitive cr rich and relatively unmetamorphosed is hard to explain in the magma ocean model it could only have been formed as a quench crust if the magma ocean model is correct then alha81001 like material should be abundant on the surface of vesta and the vestoids

eemian interglacial reconstructed from a greenland folded ice core efforts to extract a greenland ice core with a complete record of the eemian interglacial 130 000 to 115 000 years ago have until now been unsuccessful the response of the greenland ice sheet to the warmer than present climate of the eemian has thus remained unclear here we present the new north greenland eemian ice drilling neem ice core and show only a modest ice sheet response to the strong warming in the early eemian we reconstructed the eemian record from folded ice using globally homogeneous parameters known from dated greenland and antarctic ice core records on the basis of water stable isotopes neem surface temperatures after the onset of the eemian 126 000 years ago peaked at 8 4 degrees celsius above the mean of the past millennium followed by a gradual cooling that was probably driven by the decreasing summer insolation between 128 000 and 122 000 years ago the thickness of the northwest greenland ice sheet decreased by 400 250 metres reaching surface elevations 122 000 years ago of 130 300 metres lower than the present extensive surface melt occurred at the neem site during the eemian a phenomenon witnessed when melt layers formed again at neem during the exceptional heat of july 2012 with additional warming surface melt might become more common in the future

large landslides associated with a diapiric fold in canelles reservoir spanish pyrenees detailed geological geomorphological mapping trenching and electrical resistivity imaging abstract detailed geomorphological geological mapping in canelles reservoir the spanish pyrenees reveals the presence of several large landslides overlooked in previous cartographic works one of the slope movements designated as the canelles landslide corresponds to a 40 10 6 m 3 translational landslide reactivated in 2006 by a severe decline in the reservoir water level the geomorphic features mapped in the upper part of the canelles landslide including surface ruptures corroborated by electrical resistivity imaging and trenching indicate multiple displacement episodes previous to the 2006 human induced event consistently the stratigraphic and structural relationships observed in a trench record at least two displacement events older and larger in magnitude than the 2006 reactivation the oldest recorded event occurred in the 6th to 7th centuries and the second in 1262 1679 yr ad this latter episode might be correlative to the 1373 ribagorza earthquake m w 6 2 which caused the reactivation of a landslide and the consequent destruction of a village in the adjacent valley the available data indicate that over more than one millennium the kinematics of the landslide has been characterised by discrete small displacement episodes these data together with the available literature on rapid rockslides do not concur with the acceleration predicted by modelling in a previous investigation which foresees a speed of 16 m s 1 despite the low average dip of the sliding surface 9 10 this case study illustrates that the trenching technique may provide valuable practical information on the past behaviour of landslides covering a much broader time span than instrumental and historical records

quantifying rainfall controls on catchment scale landslide erosion in taiwan landslide erosion is a dominant hillslope process and the main source of stream sediment in tropical tectonically active mountain belts in this study we quantified landslide erosion triggered by 24 rainfall events from 2001 to 2009 in three mountainous watersheds in taiwan and investigated relationships between landslide erosion and rainfall variables the results show positive power law relations between landslide erosion and rainfall intensity and cumulative rainfall with scaling exponents ranging from 2 94 to 5 03 additionally landslide erosion caused by typhoon morakot is of comparable magnitude to landslide erosion caused by the chi chi earthquake mw 7 6 or 22 24 years of basin averaged erosion comparison of the three watersheds indicates that deeper landslides that mobilize soil and bedrock are triggered by long duration rainfall whereas shallow landslides are triggered by short duration rainfall these results suggest that rainfall intensity and watershed characteristics are important controls on rainfall triggered landslide erosion and that severe typhoons like high magnitude earthquakes can generate high rates of landslide erosion in taiwan copyright 2012 john wiley sons ltd

a review of methods used to estimate initial landslide failure surface depths and volumes abstract this paper presents an overview of existing methods developed to characterize initial landslide failure surfaces and compute volumes based on surface information when it is buried this paper reviews the simplest models such as volume estimation based on ellipsoids and the information that can be obtained from surface displacement and morphology a simple method to define the volume of a rockslide using the identified discontinuities is also outlined the sloping local base level slbl which is able to automatically obtain a possible failure surface on the basis of a digital elevation model dem is described the balanced cross section methods applied to landslides are illustrated and can give the depth of the failure surface using predefined assumptions such as vector displacement parallel to the failure surface we can obtain an approximation of the failure surface either along translational or circular slides and this method can be improved by adding a mass balance equation recent work has also shown that using an inverse model a mass balance equation and assumptions about the rheology enables estimation of the failure surface these methods are illustrated with examples and they are applied to case studies and compared when the data available makes it possible the advantages and disadvantages of the methods are discussed this paper shows that the use high resolution topography and interpretation of the morphology is underexploited to extract information about failure surfaces geometry

deformation in the vicinity of ice divides calculs numeriques aux elements finis de la variation de la vitesse horizontale avec la profondeur au voisinage d une difference de la glace symetrique isotherme et ou glissement sur un lit plat

integrated high resolution geophysical investigations as potential tools for water resource investigations in karst terrain karstic aquifers can be particularly vulnerable to both pollution from surface activities and large scale dewatering from mineral winning operations this is because of the enhanced vertical and lateral flow paths resulting from the dissolution of carbonate species by rainfall often this process results in the development of voids that can range in size from several centimetres to several tens of metres to date groundwater vulnerability maps for england and wales including karst areas have been produced using a methodology that does not consider the presence of karst features the uncertainties that are presented by the potential for pollution by the presence of water carrying conduits in karst areas where there are proposed or existing limestone quarries require new techniques for detecting and delineating underground cave systems in order for any mapping technique to provide an acceptable assessment of vulnerability the location and spatial distribution of high permeability flow paths need to be established of the available geophysics techniques that may allow for the identification of such features microgravity and resistivity imaging are likely to be the most successful microgravity surveying has the potential to identify the presence and location of such voids and with the integration of electrical tomographic work can provide targets for the location of monitoring boreholes whilst these techniques are intensive and may not be cost effective on a regional scale they do have the potential to provide high resolution data over smaller areas which would be invaluable to any site or area specific assessment of vulnerability

electrical imaging of sliding geometry and fluids associated with a deep seated landslide la clapiere france this paper deals with the applicability of electrical resistivity tomography ert for the recognition of large landslide structures at depths which have never previously been imaged accurately one of the most studied and instrumented deep landslides in europe is taken as an example the la clapiere landslide the first stage of the study consisted of an accurate geological mapping taking into account a morphological analysis of gravitational deformations this allowed a very fine definition of the landslide structure that could be compared with three provided ert profiles performed within the landslide body very good correlations were obtained for the determination of sub horizontal structures and associated fluid circulations it confirmed the position of the sliding surface that reached a maximum depth of 100 m forward computing was however necessary to determine the influence and then the presence of vertical discontinuities it supports the use of ert as an efficient tool for large scale landslide imaging such as deep seated landslides copyright 2010 john wiley sons ltd

apollo 14 mare basalts petrology and geochemistry of clasts from consortium breccia 14321 eleven mare basalt clasts have been extracted from polymict lunar breccia 14321 for a combined petrologic and geochemical study by our consortium ten of these clasts are high al low ti mare basalts similar to those discovered previously at apollo 14 the other is a highly evolved tridymite ferrobasalt with low al and intermediate ti contents a high al ilmenite ferrobasalt from lunar breccia 14305 is the most evolved high al basalt described from the apollo 14 site the major and trace element characteristics of the basalts studied here allow them to be grouped into five compositional types that range from lree depleted to lree enriched some of these types may be related by varying percents of partial melting of the same source but at least two separate sources that differ by a factor of two in incompatible trace element concentrations are required the 14321 type basalts and vitrophyres have steep chondritenormalized hree slopes and may have formed by assimilation of intermediate k fra mauro kreep which is presumed to represent a partial melt of the lower crust the age of these basalts 3 9 aeons suggests that mare volcanism played an important role in the evolution of the early lunar crust

pyroxene spectroscopy revisited spectral compositional correlations and relationship to geothermometry the authors wish to thank the various agencies which have provided the necessary support for this project including grants in aid of research from sigma xi the scientific research society to e a c the geological society of america grant 3741 87 to e a c and nasa planetary geology and geophysics grant nagw 642 to m j g

high resolution imaging of the high agri valley basin southern italy with electrical resistivity tomography abstract the first high resolution images of the fault controlled high agri valley basin obtained with the electrical resistivity tomography are presented the agri valley is one of the more complex components of the quaternary fault network of the apennine chain the geometry of the pre quaternary bedrock the location and dip of the master fault and the tectonic evolution of the basin are still a subject of debate therefore deep electrical resistivity tomography integrated with stratigraphic analyses has been carried out to improve knowledge of the geological setting of the basin the high resolution electrical images allow us to reconstruct the complex geometry of the basin the electrical imaging highlights the irregular shape of the basin which is bordered by shallow faults and filled with pleistocene alluvial deposits in longitudinal cross section the basin appears as a mosaic of fault bounded blocks forming three different depocenters separated by intrabasinal highs in transverse cross section the basin is an irregular graben locally asymmetric to the northeast and with secondary grabens due to antithetic faults

reflectance spectroscopy of plagioclase dominated mineral mixtures implications for characterizing lunar anorthosites remotely anorthositic rocks dominate the moon s upper crust as remnants of the lunar magma ocean lmo small variations in the mineralogy of these rocks may hold key information about the homogeneity of lmo composition and solidification processes orbital near infrared nir sensors are sensitive to mineralogy but technologic advances have only recently enabled detection of the plagioclase component in crustal rocks based on an absorption band centered near 1250 nm anorthosites occupy a unique mineralogic range that is well suited for nir studies the highly transparent component plagioclase is present in high abundances while the spectrally dominant mafic or oxide minerals are present in only minor abundance as a result spectra of anorthosites are more likely than many other rock types to contain visually discernable signatures from more than one mineral component facilitating their identification and characterization in nir data in support of new nir measurements for the moon we present laboratory spectral analyses of well controlled plagioclase dominated mineral mixtures we focus on the spectral effects of varying mafic and oxide composition and abundance in mixtures with a common plagioclase end member the results demonstrate that plagioclase can be a significant contributor to reflectance spectra when strongly absorbing minerals are present in low abundance we show that the contribution of plagioclase is more pronounced in mixtures with pyroxenes and certain spinels but more easily masked in mixtures containing small amounts of olivine differences in minor mineral composition are clearly expressed in bulk spectra modeling of mixtures using a hapke nonlinear approach accurately estimates mineral abundances in laboratory spectra to within 5 vol for mixtures with 90 vol plagioclase together these results imply that not only should orbital nir data sets be able to discern the presence of plagioclase in anorthositic crustal exposures but also that detailed information about anorthosite mineral assemblages can be reliably accessed in reflectance spectra

implications of the form of the flow law for vertical velocity and age depth profiles in polar ice valeurs des exposants de la loi de fluage des glaciers devon island canada et camp century groenland

aspects of landslide activity in the mercantour massif and the french riviera southeastern france abstract landslides pose serious hazards in the mercantour massif and the french riviera in southeastern france the context for landslide development is a particularly favourable one both in terms of the geomorphic and structural setting of this alpine region and of the climatic hydrologic and seismic factors that trigger such failures high mountain relief and steep slopes constitute a very favourable setting for failures affecting massive basement rocks and a very heterogeneous sedimentary cover whose resistance has been weakened by weathering tectonic stresses and cambering due to gravity among trigger factors the important appears to be the precipitation regime rainfalls are commonly concentrated into short high intensity downpours or into bursts of sustained falls over periods of several days leading to soil saturation and lubrication of potential failure planes snowmelt also contributes to these lubrication processes earthquakes affecting this region are also a potentially important landslide trigger however while a lot of work has been done on the relationship between extreme climatic events and landslide activity much less is known of the trigger effects of earthquakes both the background factors that promote landslide development and the factors that trigger such failures are discussed within a time frame of landslide development progressive changes in soil strength due to weathering rock cambering and shattering processes lead to long term reduction in resistance superimposed on these progressive changes are episodic triggerings related to rainfall and snowmelt episodes or earthquakes landslides may occur as shallow low volume one time events or may be part of a progressive long term failure the former generally affect unconsolidated or clay rich sedimentary rocks especially on the coastal hillslopes of the french riviera a notable exception of a major voluminous one time event was the submarine landslide of the var delta in 1979 this landslide like numerous other smaller subaerial landslides onland was largely a result of human activities this landslide occurred following extensive modification of the var delta and notably reclamation of the steep fine grained delta front deforestation quarrying urbanisation and road network developments are various ways in which human activity has destabilized the coastal hillslopes favouring the development of numerous shallow landslides following each episode of heavy rainfall progressive landslides on the upper hillslopes of the mercantour massif have developed over long time spans order of 101 to 105 yrs and have involved more complex interactions between lithological controls slope characteristics and trigger factors the collelongue and bois de malbosc landslides have evolved into now stable failures buttressed by resistant migmatitic diorites or amphibolites the more voluminous and well monitored clapiere landslide is a relatively simple rotational landslide of the toe failure type this active landslide poses a serious to inhabitants and infrastructure in the tinee valley the importance of continued field monitoring modelling and mapping of landslides and their hazards is emphasised

using the modified gaussian model to extract quantitative data from lunar soils 1 the lunar soil characterization consortium lscc has examined and characterized a suite of lunar soils with a wide range of compositions and maturities the purpose of this study is to compare the vis nir spectral properties of these lunar soils with their petrologic and chemical compositions using the modified gaussian model mgm to obtain quantitative data about the character of relatively weak near infrared absorption bands useful compositional information can be extracted from high quality soil spectra using the mgm the model had some difficulty fitting absorption bands in the 2 mm region of the lunar spectrum but bands in the 1 and 1 2 mm regions provided physically realistic results the model was able to distinguish high ca and low ca pyroxenes in the lscc suite of lunar soils in the appropriate relative abundance in addition unexpected insights into the nature and causes of absorption bands in lunar soils were identified for example at least two distinct absorption bands are required in the 1 2 mm region of the spectrum and neither of these bands can be attributed to plagioclase or agglutinates but are found instead to be largely due to pyroxene

characterization of the 1 2 μm m1 pyroxene band extracting cooling history from near ir spectra of pyroxenes and pyroxene dominated rocks the 1 2 m band in near infrared spectra of pyroxenes results from fe2 in the m1 crystallographic site the distribution of fe and mg between the m1 and m2 sites is in part a function of the cooling rate and thermal history of a pyroxene combining near infrared and mssbauer spectra for a series of compositionally controlled synthetic mg fe ca pyroxenes we quantify the strength of the 1 2 m band as a function of fe2 in the m1 site near infrared spectra are deconvolved into component absorptions that can be assigned to the m1 and m2 sites using the modified gaussian model the relative strength of the 1 2 m band is shown to be directly related to the amount of fe2 in the m1 site measured by mossbauer spectroscopy the strength of the 1 2 m band relative to the combined strengths of the 1 2 and 2 m bands or the m1 intensity ratio is calculated for 51 howardite eucrite and diogenite hed meteorites diogenites and cumulate eucrites exhibit the lowest m1 intensity ratios consistent with their formation as slowly cooled cumulates basaltic eucrites exhibit a large range of m1 intensity ratios all of which are consistently higher than the diogenites and cumulate eucrites this example illustrates how the m1 intensity ratio can be a used as a tool for characterizing the cooling history of remotely detected pyroxene dominated rocks

mineralogical and chemical characterization of lunar highland soils insights into the space weathering of soils on airless bodies 1 with reflectance spectroscopy one is measuring only properties of the fine grained regolith most affected by space weathering the lunar soil characterization consortium has undertaken the task of coordinated characterization of lunar soils with respect to their mineralogical and chemical makeup it is these lunar soils that are being used as ground truth for all airless bodies modal abundances and chemistries of minerals and glasses in the finest size fractions 20 45 10 20 and 10 m of four apollo 14 and six apollo 16 highland soils have been determined as well as their bulk chemistry and is feo values bidirectional reflectance measurements 0 3 2 6 m of all samples were performed in the reflectance experiment laboratory a significant fraction of nanophase fe0 np fe0 appears to reside in agglutinitic glasses however as grain size of a soil decreases the percentage of total iron present as np fe0 increases significantly whereas the agglutinitic glass content rises only slightly this is evidence for a large contribution to the is feo values from the surface correlated nanophase fe0 particularly in the 10 m size fraction the compositions of the agglutinitic glasses in these fine fractions of the highland soils are different from the bulk chemistry of that size however compositional trends of the glasses are not the same as those observed for mare soils it is apparent that the glasses in the highland soils contain chemical components from outside their terrains it is proposed that the apollo 16 soils have been adulterated by the addition of impact transported soil components from surrounding maria

geophysical characterization of a landslide site in the himalayan foothill region abstract a combination of electrical resistivity seismic refraction and spectral analysis of surface waves sasw have been used for the characterization of a landslide site in the mohand area of the himalayan foothills near dehradun primary attention was drawn to the determination of the thickness of the landslide body its possible slip surface and evaluation of hydrogeological conditions related to the occurrence of a landslide in the study area this was accomplished by defining the electrical resistivity and seismic wave velocity of the different lithological units validation of geophysical investigations was performed by conducting a geophysical survey near boreholes and subsequently correlating geophysical parameters values with the formation known from borehole data and other geological information available in the himalayan foothills region results obtained from geophysical investigation suggest that the slip surface of the landslide approximately coincides with the top of the saturated gravely soils indicating a change in the hydrogeological conditions at the landslide site after the event the study shows that the electrical resistivity seismic refraction and sasw in combination could be an effective tool for locating a landslip surface

geophysical monitoring of moisture induced landslides a review author s whiteley js chambers je uhlemann s wilkinson pb kendall jm abstract 2018 the authors geophysical monitoring of landslides can provide insights into spatial and temporal variations of subsurface properties associated with slope failure recent improvements in equipment data analysis and field operations have led to a significant increase in the use of such techniques in monitoring geophysical methods complement intrusive approaches which sample only a very small proportion of the subsurface and walk over or remotely sensed data which principally provide information only at the ground surface in particular recent studies show that advances in geophysical instrumentation data processing modeling and interpretation in the context of landslide monitoring are significantly improving the characterization of hillslope hydrology and soil and rock hydrology and strength and their dynamics over time this review appraises the state of the art of geophysical monitoring as applied to moisture induced landslides here we focus on technical and practical uses of time lapse methods in geophysics applied to monitoring moisture induced landslide the case studies identified in this review show that several geophysical techniques are currently used in the monitoring of subsurface landslide processes these geophysical contributions to monitoring and predicting the evolution of landslide processes are currently underrealized hence the further integration of multiple parametric and geotechnically coupled geophysical monitoring systems has considerable potential the complementary nature of certain methods to map the distribution of subsurface moisture and elastic moduli will greatly increase the predictive and monitoring capacity of early warning systems in moisture induced landslide settings

the lunar rock and mineral characterization consortium deconstruction and integrated mineralogical petrologic and spectroscopic analyses of mare basalts the lunar rock and mineral characterization consortium lrmcc has conducted coordinated mineralogy petrography spectroscopy analyses of a suite of pristine lunar basalts four basalt slabs two low ti two high ti and paired thin sections were analyzed thin sections were analyzed for mineralogy petrography while the slabs were used to prepare particulate separates of major mineral phases and bulk samples mineral separates and particulate bulk samples were crushed to controlled grain sizes and their reflectance spectra measured in the nasa relab at brown university the resulting data set provides an essential foundation for spectral mixing models offers valuable endmember constraints for space weathering analyses and represents critical new ground truth results for lunar science and exploration efforts

moon near infrared spectral reflectance a first good look a positive identification of the minerals olivine plagioclase and several types of pyroxenes were made at several locations on the lunar surface by using remote measurements for example the crater aristarchus is found to have an average pyroxene composition of augite and plagioclase is obviously present a dark mantle deposit in the crater j herschel is at least partly composed of a mixture of 70o7o olivine and 30o7o pyroxene these determinations were possible because the reflectance spectra for 10 20 km diameter lunar areas have been measured for the first time in the ir spectral region 0 65 2 5 m with sufficient spectral resolution and photometric precision to define mineral electronic absorption bands the reflectance for all lunar regions observed over 100 to present continues to increase toward longer wavelengths to at least 2 5 m and several mineral absorption bands appear the telescopic spectra are of similar quality and contain features similar to laboratory spectra of lunar samples the absorption features in several spectra have been quantitatively analyzed using newly developed computer processing techniques including thermal flux removal and absorption band fitting to produce these mineral identifications detection and quantitative analysis of these absorptions provide a much improved basis for remotely determining and mapping surface mineralogy quantitatively from the ground or using airborne or spacecraft platforms

seventeen years of the la clapiere landslide evolution analysed from ortho rectified aerial photographs we present a new method of digital elevation model dem calculation from aerial photographs and apply this method to the la clapiere landslide in the mercantour massif in eastern france the method uses new techniques of image correlation and of restitution of camera parameters the calculated dems are used to ortho rectify three aerial photographs acquired between 1983 and 1999 measurements made from these ortho rectified images show that the average velocity of the landslide was of 1 7 cm day with the rate of the headscarp retreat of 4 1 cm day and the toe of the landslide advancing at 1 7 cm day between 1983 and 1999 within the landslide the velocity field is are relatively homogeneous although their directions are locally heterogeneous scree slopes and scarps develop in an heterogeneous way within the landslide because the headscarp moves faster than the front of the landslide material spreads laterally at the scree slopes and or is eroded at the front of the landslide by the river and or is accumulated within the landslide on a low slope area located above a competent bar called igliere bar d 2002 elsevier science b v all rights reserved

paraglacial gravitational deformations in the sw alps a review of field investigations 10be cosmogenic dating and physical modelling catastrophic deep seated landslides dsl are generally considered to be the result of large slope deformations also known as deep seated gravitational slope deformation dsgsd this paper aims to build a synthesis of multiple studies made in the tinee valley southern french alps to assess the geometrical kinematical mechanical and chronological relationships between these two gravitational processes at the scale of the valley data issued from geological geomorphological and 10be dating indicate a clear geometrical link between dsgsd and dsl occurring at the base of the slope and suggest that gravitational slope evolution began after the glacial retreat 13 ka bp this is supported by the example of the well documented la clapiere slope a continuous evolution process is characterized geometrically and temporally from geomorphic observations and analogue modelling coupling structural geomorphological physical and chronological studies allowed us to propose a four dimensional 4d deformation model mechanically correlated with progressive failure concept the validity and variability of this reference site are discussed at the valley scale taking isola and le pra slope deformation as examples it allows a rough estimation of the state of slope deformation at the valley scale to be constructed and the slope evolution with time to be considered this 4d model could then be considered as a reference for other deep seated gravitational slope deformations in comparable alpine valleys

vesta vestoids and the howardite eucrite diogenite group relationships and the origin of spectral differences spectra of asteroid 4 vesta and 21 small estimated diameters less than 10 km asteroids with vesta like spectral properties vestoids were measured at visible and near infrared wavelengths similar to0 44 to similar to1 65 mum all of the measured small asteroids except for 2579 spartacus have reflectance spectra consistent with surface compositions similar to eucrites and howardites and consistent with all being derived from vesta none of the observed asteroids have spectra similar to diogenites we find no spectral distinction between the 15 objects tabulated as members of the vesta dynamical family and 6 of the 7 sampled non family members that reside just outside the semi major axis a eccentricity e and inclination i region of the family the spectral consistency and close orbital a e i match of these non family objects to vesta and the vesta family imply that the true bounds of the family extend beyond the subjective cut off for membership asteroid 2579 spartacus has a spectrum consistent with a mixture of eucritic material and olivine spartacus could contain olivine rich material from vesta s mantle or may be unrelated to vesta altogether laboratory measurements of the spectra of eucrites show that samples having nearly identical compositions can display a wide range of spectral slopes finer particle sizes lead to an increase in the slope which is usually referred to as reddening this range of spectral variation for the best known meteoritic analogs to the vestoids regardless of whether they are actually related to each other suggests that the extremely red spectral slopes for some vestoids can be explained by very fine grained eucritic material on their surfaces

rapid least squares inversion of apparent resistivity pseudosections by a quasi newton method1 a fast inversion technique for the interpretation of data from resistivity tomography surveys has been developed for operation on a microcomputer this technique is based on the smoothness constrained least squares method and it produces a two dimensional subsurface model from the apparent resistivity pseudosection in the first iteration a homogeneous earth model is used as the starting model for which the apparent resistivity partial derivative values can be calculated analytically for subsequent iterations a quasi newton method is used to estimate the partial derivatives which reduces the computer time and memory space required by about eight and twelve times respectively compared to the conventional least squares method tests with a variety of computer models and data from field surveys show that this technique is insensitive to random noise and converges rapidly this technique takes about one minute to invert a single data set on an 80486dx microcomputer

the polymict eucrites the polymict eucrites are a suite of about 14 polymict achondritic meteorites that contain at least 90 vol of eucritic material and are found both in antarctica and elsewhere they are part of a continuum of polymict breccias that includes howardites and polymict diogenites rare gas data suggest that some are gas rich regolith breccias the clasts contained in polymict eucrites sample a variety of lithologies from their parent body and include eucritic clasts alkali enriched eucrites pyroxene cumulate eucrites two pyroxene mafic rocks possibly feldspar cumulate eucrites diogenites fayalitic lithologies and a variety of other mineral clasts the eucritic clasts are probably samples of near surface lithologies on the parent body but the presence of two pyroxene mafic rocks is considered to be evidence of magmatic activity at pressures in excess of 1 kbar in the parent body partial melt models may explain some of the diversity among the clasts but cumulus processes are believed to have been important if pressures greater than 1 kbar are confirmed then the basaltic achondrite parent body bap must have a diameter in excess of 200 km the variety of lithologies suggests that not all basaltic achondrites are samples of igneous rocks formed by single stage melting of a chondritic asteroid but are instead samples of an evolved and diverse crust produced by serial magmatism

geophysical geotechnical and hydrological investigations of a small landslide in the french alps abstract geophysical geotechnical and hydrological surveys were conducted in the french alps on a small landslide in black marl material to assess the stability the geophysical survey consisting of electromagnetic geo electric and relative differences in water content the data on the basal slip surface together with geotechnical parameters cohesion and angle of internal friction were used to make a stability analysis this analysis revealed that a groundwater level of 4 m below the ground surface is the critical threshold for reactivating the landslide the hydrological investigation which entailed measurements of saturated permeability and pressure heads indicated that instability depended on long term wet conditions with little evapotranspiration

electrical resistivity tomography to investigate geological structures of the earth s upper crust it is important to have detailed knowledge of the electrical properties of the earth s crust in order to recognize geological structures and to understand tectonic processes in the area surrounding the german continental deep drilling project ktb we have used dc dipole dipole soundings to investigate the electrical conductivity distribution down to a depth of several kilometres we have adapted the electrical resistivity tomography ert technique a well established near surface method to large scale experiments independent transmitting and receiving units were used to realize the concept of simultaneous multichannel registration of the scalar electrical potential at 44 dipoles the measured data yielded apparent resistivities which were inverted to a 2d resistivity model ranging from the surface down to a depth of 4 km two highly conductive structures with steep inclination were detected they are expected to be major fault zones embedded in a metamorphic body the rather low resistivity 10 m can be explained by the existence of graphitic minerals and or electrolytic fluids

flow law for ice in polar ice sheets theories of glacier flow are based commonly on the assumption that ice is not a newtonian fluid but has a non linear stress dependent viscosity1 5 here we re examine the spreading of antarctic ice shelves and suggest that the data cannot define a unique flow law tilt measurements in four boreholes in both the arctic and antarctic seem to show that a linear flow law e a1 where a1 10 15 s 1 pa 1 at 28 c where e is the effective strain rate and the effective shear stress may be just as appropriate for describing the flow of polar ice sheets

deep structures of slopes connected with sandstone crags in the upland area of the świetokrzyskie holy cross mountains central poland abstract deep seated gravitational deformations of slopes are commonly observed and described in mountains but faintly manifested and thus neglected in upland areas thanks to the geophysical methods e g ert as well as detailed surface surveys and studies in caves such deformations have been discovered and described in the region of the wietokrzyskie holy cross mountains central poland which is an upland area of usually gentle slopes of a height of several tens of metres the deformations which have been studied on 20 30 m high slopes formed of sandstone series alternating with claystone siltstone and heterolithe series represent various movements from slight rotational and translational ca 1 m movements through horizontal and vertical shifts of several metres to significant dislocations of sandstone corestones embedded within the regolith forming the slopes the last mentioned structures are currently relics completely masked by subsequent slope processes and their origin should be related to specific periglacial and even sub glacial conditions of the pleistocene on the other hand as confirmed by radiocarbon dating and other mapping slight movements of relatively low slopes can even be active nowadays these deformations that occur in regions of a relatively low relief and have so far been neglected or considered to be unique are possibly even more frequent and should be studied using modern geophysical and other methods

ages of mare basalts on the lunar nearside the chronology of lunar volcanism is based on radiometric ages determined from apollo and luna landing site samples regional stratigraphic relationships and crater degradation and size frequency distribution data for units largely defined prior to the end of the apollo program here we report on new crater size frequency distribution data for 139 spectrally and morphologically defined basalt units which are exposed in six nearside impact basins australe tranquillitatis humboldtianum humorum serenitatis and imbrium crater size frequency distribution measurements are a statistically robust and accurate method to derive absolute model ages of unsampled regions of the moon compared to crater degradation ages crater size frequency ages performed on spectrally defined units offer significant improvements in accuracy our investigation showed that 1 in the investigated basins lunar volcanism was active for at least 1 5 2 0 b y starting at about 3 9 4 0 b y and ceasing at 2 0 b y 2 most basalts erupted during the late imbrian period at about 3 6 3 8 b y 3 significantly fewer basalts were emplaced during the eratosthenian period 4 basalts of copernican age were not found in any of the investigated basins 5 lunar basin filling volcanism probably started within 100 m y after the formation of the individual basins we also assessed the relationship between impact basin age and the history of mare basalt emplacement in these basins we found that 1 in all pre nectarian basins australe and tranquillitatis as well as in the humboldtianum basin which is of nectarian age the distribution of surface ages is clearly dominated by only a single peak in the number of erupted units at 3 6 3 8 b y 2 in the younger basins humorum serenitatis and imbrium a second peak at 3 3 3 5 b y is observed 3 basalt eruptions younger than 2 6 b y occur only intermittently and 4 in the youngest basins serenitatis and imbrium we see an extended period of active basin filling volcanism 1 5 1 6 b y which is 500 m y longer than in the australe and humorum and even 1 0 b y longer than in tranquillitatis and humboldtianum

acquisition of water chemistry in a mobile fissured basement massif its role in the hydrogeological knowledge of the la clapiere landslide mercantour massif southern alps france abstract groundwater flowpaths of the la clapiere landslide are studied by chemical and isotopic water analysis and modeling of the landslide springs in our case it appears that sulfate can be taken as a chemical tracer of the different flowpaths on the gneissic slope of la clapiere geochemical modeling explains sulfate concentrations from 0 to 130 mg l by dissolution of sulfurous minerals present in the gneisses such a variability of the concentrations measured in the springs is due to different infiltration paths direct paths through the basement so 4 2 10 60 mg l or indirect path through superficial deposits like screes or fluvio glacial terrains which cover the basement so 4 2 60 130 mg l the high concentrations 600 800 mg l cannot be explained by thermodynamic geochemical simulations and they reveal triassic gypsum dissolution hidden under the studied slope so two main flowpaths are differentiated in the la clapiere landslide 1 flow through low permeable triassic deposits pinched under the foot of the landslide 2 flow through a more permeable fissured basement with different flow paths and consequently with different transit times due to the anisotropic nature of the top and the central part of the landslide

reconnaissance geophysical methods in landslide investigations abstract landslides are a natural hazard in many countries and often affect civil engineering structures and projects three aspects in particular require examination in a geotechnical appraisal of a landslide s stability in engineering terms 1 the definition of its three dimensional shape with particular reference to shear surfaces and failure planes 2 the definition of the hydrogeological regime with regard to water input to the landslide and its distribution within the slip mass 3 the detection of movement by or within the slip mass and the characterisation of such movements the site investigation costs may be very high since landslides may be extremely large structurally complex and topographically severe it is therefore advantageous in suitable circumstances to carry out reconnaissance geophysical surveys to define the structure and to guide optimum siting of boreholes and pits and ultimately the installation of piezometers inclinometers etc standard surface geophysical techniques including the seismic electrical resistivity acoustic emission and borehole methods have all been applied with varying success to look at a landslide before a major site investigation commences in recent years electromagnetic methods have been the subject of considerable research in this field and significant advances have been made in this paper the application of the above geophysical methods at the reconnaissance stage in a landslide investigation has been reviewed and illustrated with several case histories taken from different geological settings

the ice flow velocity profile for dye 3 greenland uniaxial compression tests were made on 72 deep ice core specimens taken from 14 depth intervals between 247 m and 2021 m on the dye 3 greenland ice core test results give stress exponent values ranging from 2 7 to 3 2 which are in close agreement to the 3 0 measured on laboratory manufactured polycrystalline ice specimens these test results are compared with similar measurements made in a field laboratory immediately after the ice core was recovered the data sets showed no significant differences over the four year time span the horizontal velocity profile is calculated for dye 3 using a strain rate enhancement factor relationship and using stress exponent and activation energy values measured for artificial laboratory ice the calculated profile is in good agreement with the results from direct borehole tilting measurements this is the first time such a close correlation has been affected between laboratory generated experimental data and field measurements in the analysis of a horizontal velocity profile for a large ice sheet

near infrared spectral reflectance of mineral mixtures systematic combinations of pyroxenes olivine and iron oxides near infrared spectral reflectance data are presented for systematic variations in weight percent of two component mixtures of ferromagnesian and iron oxide minerals mixtures were chosen for application to the study of the dark materials on mars but the results are equally applicable to mafic and ultramafic assemblages elsewhere in the solar system olivine spectral features are greatly reduced in contrast by admixture of other phases but remain distinctive even for low olivine contents clinopyroxene and orthopyroxene mixtures show resolved pyroxene absorptions near 2 m the addition of limonite greatly modifies pyroxene and olivine reflectance but does not fully eliminate distinctive spectral characteristics using only spectral data in the 1 m region it is difficult to differentiate orthopyroxene and limonite goethite in a mixture additional spectral coverage or other evidence may be required for a unique interpretation all composite mineral absorptions observed in this study are either weaker than or intermediate in strength to the end member absorptions and have bandwidths greater than or equal to those for the end members in general spectral properties in an intimate mixture combine in a complex nonadditive manner with features demonstrating a regular but usually nonlinear variation as a function of end member phase proportions

measuring moonlight an overview of the spatial properties lunar coverage selenolocation and related level 1b products of the moon mineralogy mapper 1 the moon mineralogy mapper m3 a high resolution high precision imaging spectrometer flew on board india s chandrayaan 1 mission from october 2008 through august 2009 this paper describes some of the spatial sampling aspects of the instrument the planned mission and the mission as flown we also outline the content and context of the resulting level 1b spatial products that form part of the m3 archive while designed and planned to operate for 2 years in a 100 km lunar orbit m3 was able to meet its lunar coverage requirements despite the shortened mission an increase of the orbit altitude to 200 km and several relevant problems with spacecraft attitude timing and ephemeris the unexpected spacecraft issues required us to invent a novel two step approach for selenolocation leveraging newly available lunar reconnaissance orbiter lunar orbiter laser altimeter lola topography and an improved spacecraft ephemeris we have created a method that permits us to bootstrap spacecraft attitude estimates from the image data themselves this process performs a nonlinear optimization to honor a set of data derived image to image tie points and image to lola control points error analysis of the final results suggests we have converged to a selenolocation result that has image to image root mean square rms errors less than 200 m and image to lola rms errors less than 450 m despite using data derived spacecraft attitude results the level 1b products include the lunar coordinates resulting from this inversion process and 10 relevant observational geometry parameters that fully characterize the ray tracing geometry on a pixel by pixel basis

geophysical survey to estimate the 3d sliding surface and the 4d evolution of the water pressure on part of a deep seated landslide geophysical surveys were conducted on the very unstable front part of the la clapiere landslide in the french alps alpes maritimes the electrical resistivity survey was carried out to obtain for the first time on this deep seated landslide 3d information on the slipping surface and the vertical drained faults moreover we planned to follow within time 6 months the evolution of the saturated zones presence of gravitational water and their percolation into the shearing zones our 4d results showed the importance of the complex water channelization within the slope and relation to geological discontinuities

electrical resistivity tomography technique for landslide investigation a review abstract in the context of in situ geophysical methods the electrical resistivity tomography ert is widely used for the near surface exploration of landslide areas characterized by a complex geological setting over the last decade the technological improvements in field data acquisition systems and the development of novel algorithms for tomographic inversion have made this technique more suitable for studying landslide areas with a particular attention to the rotational translational and earth flow slides this paper aims to present a review of the main results obtained by applying ert for the investigation of a wide spectrum of landslide phenomena which affected various geological formations and occurred in different geographic areas in particular significant and representative results obtained by applying 2d and 3d ert are analyzed highlighting the advantages and drawbacks of this geophysical technique finally recent applications of the time lapse ert tl ert for landslide investigation and the future scientific challenges to be faced are presented and discussed

mineralogical survey of the anorthositic feldspathic highlands terrane crust using moon mineralogy mapper data abstract spectroscopic data from the moon mineralogy mapper m 3 instrument are used to study the mineralogy of the central peak or peak ring of 75 craters located in the lunar anorthositic feldspathic highlands terrane fht a as defined by jolliff et al 2000 the thickness of south pole aitken spa ejecta at the location of the selected craters is estimated crustal thickness models are used with empirical cratering equations to estimate the depth of origin of the material excavated in the studied central peaks and its distance to the crust mantle interface the goal of this survey is to study the composition of the fht a crust and the extent of its potential lateral and vertical heterogeneities high calcium pyroxene hcp and featureless spectra are mostly detected throughout the entire fht a whereas the number of pure plagioclase detections is small no relationship between the central peak composition and the distance to spa or the depth within the spa ejecta is observed the spa ejecta material cannot be spectrally distinguished from crustal material we interpret the paucity of plagioclase spectra in the fht a which contrasts with more frequent plagioclase detections in the central peaks of craters sampling the crust in younger lunar terranes using identical spectroscopic techniques martinot et al 2018b as a possible effect of terrane maturation or of mixing with mafic components that mask their signature in the visible near infrared overall the fht a appears homogeneous laterally however data hint at a pyroxene compositional change with increasing depth from high calcium content in the upper crust towards less calcic compositions with increasing depth which is consistent with prior studies of the architecture of the lunar crust

was the greenland ice sheet thinner in the late wisconsinan than now ice of wisconsinan origin which constitutes the basal layers of the ice caps in arctic canada and greenland flows three to four times more readily than the holocene ice above a model based on simple ice sheet profile theory is set up for the thickness response of the interior ice sheet regions to the progressive thinning of this soft layer the model is applied to calculate the thickness response of the greenland ice sheet at the locations dye 3 and crete and of the devon island ice cap in arctic canada it is concluded that the mechanism contributes significantly to the thickness change of the greenland ice sheet presently at a rate of about 1 cm yr 1 and that this rate of change will persist potentially over thousands of years to come as regards the devon island ice cap most of the estimated 15 thickness increase has already been accomplished a further consequence is that in the late wisconsinan ice thicknesses of the interior regions of the greenland ice sheet were likely to have been no greater and possibly even less than at present in spite of the larger geographical extent of the ice sheet it is argued that the glacial interglacial cycles of accumulation rate and ice temperature are likely to enhance this ice thickness variation

geology of grimaldi basin on the moon evidence for volcanism and tectonism during the copernican period abstract the grimaldi basin centered at 5 2 s 68 6 w is a 400 km diameter highly degraded pre nectarian double ring impact structure on the moon located near the western edge of the oceanus procellarum hyperspectral data from moon mineralogy mapper m3 feo estimates from kaguya lunar multiband imager mi data and tio2 estimates from wac 321 415 nm ratio have been used to study the compositional make up of the grimaldi mare basalt additionally morphological studies and crater chronology have been carried out using moderate to very high resolution images from lunar reconnaissance orbiter lro to decipher the geological evolution of the grimaldi basin mare grimaldi are dominantly composed of clino pyroxenes with olivine and or of feldspathic mixing with lateral as well as depth wise variations in composition in the south central part the basin experienced copernican aged volcanism 700 ma ago resulting in the formation of olivine bearing basalts with high feo and tio2 content cross cutting of small copernican craters by fresh wrinkle ridges and lobate scarps has been observed at several places in the basin suggesting that tectonic activities occurred in the basin within the past 50 ma 1 ga thus similar to the oceanus procellarum region grimaldi basin was also geologically active during the copernican period

kinematic behaviour of a large earthflow defined by surface displacement monitoring dem differencing and ert imaging abstract large earthflow type landslides are destructive mass movement phenomena with highly unpredictable behaviour knowledge of earthflow kinematics is essential for understanding the mechanisms that control its movements the present paper characterises the kinematic behaviour of a large earthflow near the village of ubietova in central slovakia over a period of 35 years following its most recent reactivation in 1977 for this purpose multi temporal spatial data acquired by point based in situ monitoring and optical remote sensing methods have been used quantitative data analyses including strain modelling and dem differencing techniques have enabled us to i calculate the annual landslide movement rates ii detect the trend of surface displacements iii characterise spatial variability of movement rates iv measure changes in the surface topography on a decadal scale and v define areas with distinct kinematic behaviour the results also integrate the qualitative characteristics of surface topography in particular the distribution of surface structures as defined by a high resolution dem and the landslide subsurface structure as revealed by 2d resistivity imaging then the ground surface kinematics of the landslide is evaluated with respect to the specific conditions encountered in the study area including slope morphology landslide subsurface structure and local geological and hydrometeorological conditions finally the broader implications of the presented research are discussed with particular focus on the role that strain related structures play in landslide kinematic behaviour

complexities in pyroxene compositions derived from absorption band centers examples from apollo samples hed meteorites synthetic pure pyroxenes and remote sensing data we reexamine the relationship between pyroxene composition and near infrared absorption bands integrating measurements of diverse natural and synthetic samples we test an algorithm plc involving a two part linear continuum removal and parabolic fits to the 1 and 2 m bands a computationally simple approach which can easily be automated and applied to remote sensing data employing a suite of synthetic pure pyroxenes the plc technique is shown to derive similar band centers to the modified gaussian model plc analyses are extended to natural pyroxene bearing materials including 1 bulk lunar basalts and pyroxene separates 2 diverse lunar soils and 3 hed meteorites for natural pyroxenes the relationship between composition and absorption band center differs from that of synthetic pyroxenes these differences arise from complexities inherent in natural materials such as exsolution zoning mixing and space weathering for these reasons band center measurements of natural pyroxene bearing materials are compositionally nonunique and could represent three distinct scenarios 1 pyroxene with a narrow compositional range 2 complexly zoned pyroxene grains or 3 a mixture of multiple pyroxene or nonpyroxene components therefore a universal quantitative relationship between band centers and pyroxene composition cannot be uniquely derived for natural pyroxene bearing materials without additional geologic context nevertheless useful relative relationships between composition and band center persist in most cases these relationships are used to interpret m3 data from the humboldtianum basin four distinct compositional units are identified 1 mare humboldtianum basalts 2 distinct outer basalts 3 low ca pyroxene bearing materials and 4 feldspathic materials

geophysical anatomy of counter slope scarps in sedimentary flysch rocks outer western carpathians abstract a multidisciplinary geophysical survey consisting of electrical resistivity tomography ert ground penetrating radar gpr shallow seismic refraction ssr and gravity survey gs was used to investigate the counter slope scarps one of the typical manifestations of the relaxed zones of rock massifs and the possible initial stages of deep seated landslides dsls two upper parts of the extensive dsls within the moravskoslezske beskydy mountains outer western carpathians owc built by the sedimentary flysch rock were chosen as the testing sites a combined geophysical survey on the flysch rocks was performed on both localities to enhance our present findings the survey revealed that the ert is able to reliably detect underground discontinuities which are manifested at the ground surface by one of the typical landforms tension cracks trenches pseudokarst sinkholes double crested ridges and counter slope scarps previous studies suggested that bedrock discontinuities should be depicted by high resistivity features within ert surveying according to ssr and gs expected zones of weakened rock massif were not confirmed directly underneath the superficial landforms but they were shifted based on the ssr and gs measurements the depicted high contrast transitions between high and low resistivity domains within the ert profiles were newly identified as possible manifestation of bedrock discontinuities the results of gpr measurements give only limited information on the sedimentary flysch rocks due to shallow penetrating depth and locally strong signal attenuation the combined results of multidisciplinary geophysical surveying confirmed an importance of employing more than one geophysical technique for integrated interpretations of measured data integrated interpretations of the measured geophysical data provided a new insight into massif disintegration and the geomorphic origin of the landforms related to the dsl

in situ geophysical and hydro geochemical monitoring to infer landslide dynamics pegairolles de l escalette landslide france the pegairolles de l escalette landslide is located in the central part of the languedoc region southern france it corresponds to a deep seated landslide 50 m of thickness with extremely slow slip displacement 3 4 mm year in this area the current landslide activity is associated with intense precipitation events 300 500 mm in a few days and the related dissolution of triassic evaporite layers at depth considering a relatively simple geological context and a landslide mainly controlled by slope hydrogeology this site constitutes a natural observatory to study the impact of large rain events on slope kinematics this work is based on complete and original instrumentation deployed in two nearby boreholes since 2012 the landslide is investigated down to 65 m depth by two in situ permanent observatories for geophysical electrical resistivity and deformation metric sensor spacing daily and seasonal data acquisition and hydrogeochemical monitoring pressure ph temperature electrical conductivity fluid sampling 4 depths monthly data acquisition the data recorded during the five years of investigations help us to characterize the active slip zones in the underground as well as the seasonal dynamics of the different hydrogeological units within the slope we also observe a heavy rainfall event characterized by both electrical resistivity and geochemical changes down hole which suggest different time responses of the system to the meteorological solicitations these first results point out the relevance of the downhole monitoring to progress towards a better understanding of internal landslide processes in relation to climate forcing

application of geophysical methods for the investigation of the large gravitational mass movement of sechilienne france several geophysical techniques electromagnetic profiling electrical tomography seismic refraction tomogra phy and spontaneous potential and seismic noise measurement were applied in the investigation of the large gravita tional mass movement of sechilienne france the aim of this study was to test the ability of these methods to characterize and delineate the rock mass affected by this complex movement in mica schists whose lateral and vertical limits are still uncertain a major observation of this study is that all the zones strongly deformed previously and at present by the movement are characterized by high electrical resistivity values 3 k m in contrast to the undis turbed mass which exhibits resistivity values between a few hundred and 1 k m as shown by the surface observa tions and the seismic results this resistivity increase is due to a high degree of fracturing associated with the creation of air filled voids inside the mass other geophysical techniques were tested along a horizontal transect through the movement and an outstanding coherency appeared between the geophysical anomalies and the displacement rate curve these preliminary results illustrate the benefits of combined geophysical techniques for characterizing the rock mass in volved in the movement results also suggest that monitoring the evolution of the rock mass movement with time lapse geophysical surveys could be beneficial resume plusieurs techniques geophysiques profil electromagnetique tomographie electrique tomographie sismique et potentiel spontane et bruit de fond sismique ont ete appliquees pour la reconnaissance du grand mouvement de ter rain de sechilienne france situe dans des micaschistes l objectif de cette etude etait de tester ces methodes geophy siques afin de caracteriser et de delimiter la masse de roche affectee par ce mouvement complexe dont la limite laterale reste incertaine l etude a montre que toutes les zones tres deformees encore actuellement et dans le passe par le mouvement sont caracterisees par de fortes valeurs de resistivite electrique superieur ea3k m tandis que dans la zone non perturbee les valeurs de resistivite sont de quelques centaines de m a1k m comme le montrent les observations de surface et les profils de tomographie sismique cette augmentation de resistivite est due a une frac turation importante associee a la creation de vides remplis d air au sein du massif les techniques electromagnetiques ps et de mesure de bruit ont ete testees le long d un profil transversal recoupant le mouvement une correlation remar quable est obtenue entre les anomalies geophysiques et le taux de deplacement ces resultats preliminaires soulignent l interet de combiner les methodes geophysiques pour caracteriser la masse de roche impliquee dans le mouvement et pour determiner l evolution du mouvement par un suivi temporel des parametres geophysiques mots cles mouvement gravitaire methodes geophysiques sechilienne meric et al 1115

the character of south pole aitken basin patterns of surface and subsurface composition using moon mineralogy mapper data we characterize surface diversity across the enormous south pole aitken basin spa by evaluating the abundance and composition of pyroxenes which are overwhelmingly the most abundant mafic mineral in the region although spa exhibits significant complexity due to billions of years of geologic processes subsequent to formation the basin has retained regular patterns of compositional heterogeneity across its structure four distinct roughly concentric zones are defined 1 a central spa compositional anomaly spaca which exhibits a pervasive elevated ca fe rich pyroxene abundance 2 a mg pyroxene annulus which is dominated by abundant mg rich pyroxenes 3 a heterogeneous annulus which exhibits localized pyroxene rich areas spatially mixed with feldspathic materials and 4 the spa exterior which is primarily feldspathic pyroxene compositions in the heterogeneous annulus are similar to those in the mg pyroxene annulus and mg rich pyroxenes also underlie the more ca fe rich pyroxene surface material across spaca the establishment of these four distinct compositional zones across spa constrains future basin evolution models serves to guide potential sample return and other science targets

geophysical characterisation of a rockslide in an alpine region a combination of geophysical methods has been used for the characterisation of a rockslide area located in the graie alps nw of italy where the construction of a roadway tunnel has been planned electrical resistivity tomography ert seismic refraction tomography srt and spectral analysis of surface waves swm have been adopted to determine the overburden thickness and the geometry of the sliding surfaces the geomechanical characterisation of rock mass was performed by means of horizontal seismic profiles hsp and sonic log in a horizontal borehole the results have been calibrated by comparing the geophysical responses with the geological evidence derived from boreholes and with the movements recorded using inclinometric probe moreover borehole geophysics results were validated by the results of laboratory measurements performed on core samples the integration of geophysical and geotechnical results allowed the definition of a subsoil model for the investigated area and provided the necessary data for the design of the roadway tunnel the study shows that surface and borehole geophysical techniques could be an efficient and cost effective tool in rockslide investigations

evolution stages of large deep seated landslides at the front of a subalpine meridional chain maritime alps france abstract studying long term evolution of gravitational slope evolution is a key to understanding deep seated landslide processes this paper deals with three large deep seated landslides dsls at a front of a subalpine meridional chain on the la marbriere slope near the town of grasse alpes maritimes france the geological framework controlling the stability and morphology of the dsls is associated with thick and tamped triassic layers of mudstone with gypsum overlain by highly faulted jurassic limestone gravitational deformation affects the entire slope involving a movement of about 1 1 10 8 m 3 of rock material it creates large disturbances in landscape morphology such as scarps counter slope scarps trenches and other typical gravitational morpho structures geomorphological mapping coupled with deep electrical resistivity tomography ert reveals a strong correlation between these morpho structures and inherited brittle tectonic features this observation relies on spatial and geometrical relations on the surface and at the depth of more than 150 m checked by ert between the most persistent fault and the gravitational morpho structures the specific distribution of the morpho structures on the basis of their morphological typologies and variations in the stage of evolution of three dsls provides an interpretation of their kinematics during the last 400 ka it appears that soft substratums combined with inherited persistent anisotropies are key factors in the development of the dsls indeed outflow of mudstone due to the lithostatic pressure imposed by individual limestone compartments has led to general slope subsidence then a progressive toppling of a rock mass may have led to the catastrophic rock collapse along bedding planes the evolution of the dsls can be divided into three distinct stages represented by three zones a young collapse stage zone 1 a pre collapse stage zone 2 and an old mature stage 400 ka zone 3 as the dsls occur on the same slope and in the same geological context this area offers interesting perspectives for understanding factors controlling the long term gravitational evolution of slopes

in situ characterization of flows in a fractured unstable slope in the case of large unstable mountain slopes the spatial repartition of the saturated zones influence the pressure repartitions in the massif and the slope stability this contribution proposes an evaluation of water origin and pressure transit time of groundwater flows from hydrochemical and isotopic measurements the objective is to propose a conceptual model of the groundwater flows and a location of the saturated zones in the slope the interpretation of time measurements of water pressure in the collapsed zone highlights i an evolution of flows with deformation that induces a damaging of the rock properties and ii the necessity to connect hydrogeological conditions and geological background in a dynamical system to analyse the pore pressure in the fractured collapsed zone

landslides in sado island of japan part i case studies monitoring techniques and environmental considerations abstract a sufficient knowledge on the kinematics and development of landslides helps to adopt proper measures that can be used to protect slopes and the environment in general this can be achieved by adequate monitoring programs this paper presents the findings of intensive monitoring activities carried out on shiidomari and katanoo landslides found in sado island of japan more than one year of observation of the two landslides allowed defining some peculiar futures of their kinematics and style of development the problem of slope instability in the two areas is generally accredited to various factors but both landslides were triggered by heavy rainfalls and snowmelt because of the outline of the area and the presence of relict topographic features the shiidomari landslide is considered to be a large scale reactivation of old slope failures the katanoo landslide is however a first time case geophysical investigations and drilling activities in shiidomari indicated the presence of two slip planes the deepest 80 100 m of these is controlled by existing lineaments monitoring data suggests that the body of the landslide has subsided as much as 1 16 m just below the main scarp but a centimeter in the central region the toe sector also experienced a significant amount of subsidence but this was counter balanced by an uplift on the opposite side of the landslide hence the landslide seems not any more active along the deepest slip surface although it may extend upward and define a series of shallow shear planes around the crown in the case of katanoo the landform characteristics differential weathering the road cut and groundwater fluctuations appeared to contribute much to determine the exact location of the landslide extensional cracks that preceded the landslide can be related to heavy rainfalls and the cold and warm cycles thereafter subsurface investigations and monitoring works indicated that the landslide has two slide blocks with different slip planes during the observation period the upper part of the landslide responded more effectively to rainfall and snowmelt than the middle and lower sections the corresponding movements however appeared to settle about three months after failure there were also little strain transmissions in boreholes and no significant change in the characteristics of the landslide the kinematics of deformation of many of the slopes in sado island resembles that of shiidomari landslide but mass movements along highways and mountain roads are usually similar to katanoo landslides of the type like shiidomari may not show sudden and drastic failures but are usually long lasting and can reactivate repeatedly along new shallow shear planes monitoring works and long term supervisions in these types of landslides are useful to identify impending failures and take the right measures before they brought about large scale destruction to the environment

galileo multispectral imaging of the north polar and eastern limb regions of the moon multispectral images obtained during the galileo probe s second encounter with the moon reveal the compositional nature of the north polar regions and the northeastern limb mare deposits in these regions are found to be primarily low to medium titanium lavas and as on the western limb show only slight spectral heterogeneity the northern light plains are found to have the spectral characteristics of highlands materials show little evidence for the presence of cryptomaria and were most likely emplaced by impact processes regardless of their age

forsteritic olivine and magnesium rich orthopyroxene materials measured by chang e 4 rover abstract china s chang e 4 probe achieved the first soft landing within the south pole aitken spa basin which is the oldest largest and deepest basin on the lunar farside the deployed chang e 4 rover made in situ spectral measurements along the rover traverse during a nominal three month mission period spectral analyses imply that materials at the chang e 4 landing site have a forsteritic olivine ol and magnesium mg rich orthopyroxene opx assemblage in almost equal fractions the chang e 4 rover measured materials which were essentially mixture of multiple sources were primarily the weathering products of finsen crater ejecta plagioclase plg which has significant implication for the provenance is often spectrally transparent or featureless in the wavelength range 450 2395 nm of the in situ measured spectrum depending on the possible absence or presence of abundant plg the materials likely originated from a differentiated spa impact melt pool or from an mg suite pluton in the lunar lower crust and were less likely to originate from the lunar upper mantle

landslides triggered factors analysed by time lapse electrical survey and multidimensional statistical approach abstract a temporal imagery of water circulation in a landslide by electrical resistivity tomography ert was conducted to identify spatially and temporally the coupling between rainfalls consecutive water inflows in a sliding mass and induced resistivity variations this work is based on a multi scale experimental approach applied on the vence landslide south eastern france which is characterised by a sandy clay sliding mass on a marly limestone substratum mostly controlled by high rainfall events at the landslide scale historical geological and geotechnical data combined with field investigations and the interpretation of three ert allowed the definition of a geometrical model of the landslide and the calibration of the resistivity values on the basis of these results a permanent time lapse ert survey was designed on a specific part of the landslide coupled with water level acquisition piezometric levels and rain fall events results covering a three month period are showed the statistical analyses of all the physical parameters measured during the three months of investigation show that the matrix of correlations highlighted strong correlations between the rainfall piezometric elevation and the resistivity these first results show an accurate answer resistivity piezometric elevation that can be associated as a precursor of the reactivation of the landslide

effects of temperature on remotely sensed mineral absorption features laboratory spectral reflectance of mafic silicates has been measured over a temperature range characteristic of solar system objects to study the variation of diagnostic mineral absorption bands this information has become increasingly important with recent improvements in the quality of remotely sensed planetary data and the concurrent increase in sophistication of quantitative and qualitative spectrum analysis techniques in this study visible and near ir reflectance spectra 0 4 2 5 m of pyroxenes and olivine were obtained over a sample temperature range of 80 448 k these are the first published reflectance data for these minerals at temperatures significantly below ambient 300 k additionally thermal radiation emitted from the samples at elevated temperatures was effectively removed disclosing for the first time the high temperature reflectance behavior of pyroxenes in the diagnostic 2 m spectral region as expected from basic physical considerations fe2 crystal field absorptions in all samples become narrower with decreasing temperature the three components of the composite olivine band centered near 1 m become better resolved with decreased temperature and show changes in relative absorption strength there is not however any significant wavelength shift of the olivine reflectance minimum both orthopyroxene and clinopyroxene spectra show dramatic changes in band symmetry with temperature with the greatest change in the longer wavelength edge despite these significant changes in shape little if any change is observed in the wavelength position of reflectance minima of pyroxene absorptions near 1 m the 2 m pyroxene absorptions in contrast demonstrate major shifts of reflectance minima but in different directions in orthopyroxene spectra the band shifts to longer wavelengths with increased temperature while for the clinopyroxene spectra the band shifts to shorter wavelengths this behavior results in greatly improved spectral differentiation of orthopyroxene and clinopyroxene components in a mixture such as a basalt at reduced temperatures application of the results presented here to remote sensing mineral characterization techniques currently in use for determination of pyroxene composition can provide a moderate improvement to quantitative interpretations from 5 to 20 wt feo for orthopyroxenes and 5 wt cao for clinopyroxenes depending on planetary surface temperature

past precipitation rates derived from ice core measurements methods and data analysis ice cores in which annual layers can be identified or particular horizons dated provide a record of past precipitation rates if measured layer thicknesses can be corrected for thinning by flow since deposition total strain is usually calculated from steady state flow models because of lack of information about the ice cap s history an assumption of uniform vertical strain rate is valid at best in the upper half of the ice column complex models are needed to take account of uneven bedrock and variations in precipitation rate upstream of the borehole drilling at an ice divide avoids these complications new data analyses suggest that precipitation at camp century has fluctuated by only plus or minus 10 for the past 8500 years whereas at devon island on the opposite side of baffin bay precipitation has been uniform only for the past 1300 years with significantly higher values before that estimation of pre holocene precipitation rates is especially difficult because that ice may have an effective viscosity different from holocene ice three published estimates of pre holocene precipitation at camp century are unreliable the authors did not allow for thinning and their time scales differ appreciably data from three antarctic stations show some inconsistencies measuring concentrations of 10be in ice cores may be an alternative method of determining past precipitation rates

estimation of large scale mechanical properties of a large landslide on the basis of seismic results abstract knowledge of large scale mechanical properties is essential for estimating the stability of rock slopes being deformed by deep creep and especially for predicting a transition to rapid sliding standard geomechanical testing procedures may not result in significant values as the volume of the mass movements under consideration exceeds the volume of even the largest in situ tests by several orders of magnitude seismic measurements may help to estimate some of the relevant mechanical properties by direct correlation with the seismic velocities however not all parameters necessary for a stability analysis correlate closely with seismic velocities an alternative approach could be the geomechanical modelling of the structures and properties of the creeping or sliding mass as determined from seismic exploration in this paper we present an application of this approach to the giant landslide of koefels the development of the creeping rock mass which represents the initial phase of the mass movement has been successfully modelled by assuming a transition of the originally compact rock mass to soft rock controlled by a mohr coulomb and no tension yield criterion geomechanical parameters are determined by fitting the geomechanical model to the seismic results an apparent angle of internal friction has been determined in the range 20 24 these low values are compatible with the fact that a transition to rapid sliding took place in the past

a multidisciplinary approach to the evaluation of the mechanism that triggered the cerda landslide sicily italy abstract the present paper describes a multidisciplinary approach to the evaluation of a seismically triggered landslide that occurred in the cerda area italy on september 6 2002 about 1 h after an earthquake took place in the south tyrrhenian sea the study was focused on an analysis of the role of the seismic input in triggering the landslide in view of the evidence that no other mass movement was recorded in the adjacent areas despite geological and geomorphological spatial homogeneity the studied area is located on a slope of the western flank of the fiume imera settentrionale northern sicily which is made up of clayey arenitic rocks the slope inclines gently but is not uniform due to fluvial gravitative and rainwash processes field data dealing with global positioning system gps geology geomorphology geophysics vertical electrical sounding or ves and geochemistry soil gas fluxes and composition were acquired and analysed in order to investigate the cause effect relationships between the earthquake and the mass movement the gps survey allowed us to map the ground failures that have also been classified on the basis of their kinematical meaning i e compressive distensive or transcurrent structures the geological analysis revealed outcropping rocks and tectonic structures the geomorphologic survey highlighted the presence of preexisting landslide bodies the geophysical survey detected a buried surface located at a depth of about 100 m finally the geochemical survey showed that the gas released from the displaced mass came from a shallow depth and was not related to any active fault system the abovementioned information allowed us to interpret the landslide event as a partial reactivation of a preexisting landslide body that was triggered by the earthquake

electrical resistivity tomography ert based subsurface characterisation of pakhi landslide garhwal himalayas india pakhi landslide is one of the major debris slides of retrogressive nature along national highway nh 58 corridor from rishikesh to badrinath in garhwal himalayas india the present work is the first such attempt in one of the landslides in indian himalayas and in the present case study the subsurface characterization of the landslide was carried out with an aim to correlate the subsurface lithology slip surface and geometry of the landslide using borehole investigation and electrical resistivity tomography ert techniques the results from ert survey along and across the landslide could help to delineate different strata layers thereby deciphering the probable slip surface of the landslide activity further based on the landslide model drawn from the ert interpretations it can be stated that the crown portion of the right flank is more vulnerable to sliding phenomenon and that of the left flank is more prone to erosion the results obtained from both the borehole investigation and ert techniques are observed to be in great agreement and could complement each other for subsurface detailed investigation of landslide the integration of both these techniques provides useful information about the landslide activities and defines the geometry of the landslide hence it will be quite helpful in planning mitigation strategies as well as usefulness of each of these techniques