trace fossils from interdune deposits an example from the lower triassic aeolian tumlin sandstone central poland abstract the tumlin sandstone up to 105 m thick is the deposit of a midcontinent extensive at least 1500 km2 dune field it consists of dune deposits and of subordinate intercalations of interdune deposits the latter are represented by horizontally bedded sandstone accumulated in frequently changing conditions on dry damp and wet surface dry surface deposits predominate subordinate but relatively common are damp surface deposits with characteristic adhesion structures and wet surface deposits represented by very thin mudstone layers and horizons of wave ripples which originated in ephemeral ponds the interdune deposits contain numerous trace fossils whose occurrence is almost entirely connected with wet surface and damp surface deposits the dune deposits are devoid of trace fossils the following forms have been recognized arenicolites isp cruziana problematica diplocraterion isp gordia marina planolites montanus planolites isp palaeophycus tubularis tetrapod footprints radial structures shallow double furrows and various oval depressions in places intensive but shallow bioturbation of sediment is observable the trace fossil assemblage is similar to the scoyenia ichnofacies but lacks scoyenia and ancorichnus the assemblage is more comparable to the mixed arenicolites cruziana ichnofacies sensu bromley and asgaard 1979 the invertebrate burrows show an r selected strategy in sediment colonization around the palaeozoic mesozoic transition the highly diversified ichnofauna compared to that of the permian interdune deposits shows increased colonisation of interdunes by an invertebrate mainly arthropod fauna

trackway preservation in eolian sandstones from the permian of scotland despite the widespread conception of deserts as places almost barren of life the geologic record shows that the tracks and traces of animals are often associated with desert deposits the reluctance of some geologists to associate such tracks with eolian deposits has even led some to conclude that the tracks and therefore the rocks were formed under water eolian sandstones showing the tracks of vertebrate animals range from carboniferous to holocene in age and include such famous formations as the coconino and navajo sandstones of the united states the botucatu sandstone of brazil and the cave sandstone of southern africa three eolian sandstone formations from the permian of scotland have tracks believed to have been made by pelycosaurs anomodonts and pareiasaurs a study of these formtions has helped in interpreting how such tracks in eolian sandstones were formed and preserved two of these formations occur in isolated basins in dumfries and galloway where the tracks occur on the surface of very thin clay rich silt laminae probably deposited following a storm or small flood event the tracks from a third formation in grampian are closely associated with sheetflood deposits and contorted strata both believed to indicate the presence of water sufficient water was therefore present in both areas to give the sand the degree of cohesion necessary for track formation and preservation

devonian tetrapod trackways and trackmakers a review of the fossils and footprints abstract the earliest tetrapods are known from the upper devonian their remains are becoming better known from increasing numbers of specimens localities environments and ichnofossils each of the eight or possibly nine genera now represented by skeletal fossils is reviewed in its sedimentological faunal and stratigraphic context with an assessment of what might be inferred about the habitus and locomotory capabilities of each fossil trackways and their interpretations are then re examined in the context of the known body forms and consideration given to the degree of fit between the skeletal fossils the trackways and their interpretations the currently known devonian tetrapods are unlikely to have made any of the known tracks unless they were produced under water neither the skeletal fossils nor the trackways show good evidence of terrestrial locomotion among devonian tetrapods when the fossil material and recent phylogenetic analyses are taken in combination it appears that neither tetrapods nor limbs with digits are likely to have arisen before the frasnian this should be borne in mind in palaeoecological studies of these animals

flash flood sediments and ichnofacies of the late pleistocene homeb silts kuiseb river namibia abstract the homeb silt formation consists of eroded remnants of fine grained alluvium that were deposited within the kuiseb river valley in southern namibia during the late pleistocene in holocene times the river deeply incised its valley fill leaving steep walled castles of relict alluvium the homeb silts this study is based on the 25 m thick type exposure of homeb silts at homeb and describes flash flood sediments that were colonised by successive generations of opportunistic arthropods the stacked flood units each comprise a massive tabular siltstone bed overlain by a narrower interval of rapidly alternating sandstone and siltstone with claystone veneers these flood units are interpreted as having accumulated under semi arid climatic conditions by episodic back flooding of the kuiseb river into embayments and tributary mouths soon after deposition as the floodwaters subsided the sediment was colonised by burrowing sediment ingesting organisms mostly arthropods that produced a taenidium ichnofacies after the floodwaters had drained the exposed sediment was colonised by grasses and burrowed by terrestrial arthropods probably ants and termites resulting in an overprint of termitichnus ichnofacies with associated pelletal chambers thirteen horizons of rhizocretions and root tubules occur toward the top of the succession and indicate a gradual reduction in the frequency of flooding these immature calcic palaeosols suggest that the climate in the central namib desert 20 000 years ago was semi arid being wetter and more seasonal than the hyperarid conditions that prevail today

interferogram formation in the presence of complex and large deformation 1 sierra negra volcano in isabela island galapagos erupted from october 22 to october 30 in 2005 during the 8 days of eruption the center of sierra negra s caldera subsided about 5 4 meters three hours prior to the onset of the eruption an earthquake mw 5 4 occurred near the caldera because of the large and complex phase gradient due to the huge subsidence and the earthquake it is difficult to form an interferogram inside the caldera that spans the eruption the deformation is so large and spatially variable that the approximations used in existing insar software roi roi pac doris gamma cannot properly coregister sar image pairs spanning the eruption we have developed here a two step algorithm that can form intra caldera interferograms from these data the first step involves a rubber sheeting sar image coregistration in the second step we use range offset estimates to mitigate the steep phase gradient using this new algorithm we retrieve an interferogram with the best coverage to date inside the caldera of sierra negra

an anatomy consistent study of the lopingian eolian tracks of germany and scotland reveals the first evidence of the end guadalupian mass extinction at low paleolatitudes of pangea abstract the poor preservation and apparent monospecifity of permian tetrapod footprints from eolian paleoenvironments have thus far hampered their reliable interpretation this study clarifies how this is due to distinct and repeated ichnotaphonomic effects on trackway pattern and footprint morphology on originally inclined planes once these effects are excluded the anatomy consistent ichnotaxobases useful for ichnotaxonomy can be recognized several nomina dubia are identified among these the ichnogenus chelichnus here considered a taphotaxon the eolian ichnoassociations from the lopingian of scotland and germany include six different ichnotaxa cf capitosauroides isp eutheriodont therapsid dicynodontipus geinitzi cynodont therapsid dolomitipes isp dicynodont therapsid pachypes loxodactylus n comb pareiasaurian parareptile procolophonichnium isp small parareptile and rhynchosauroides isp non archosauriform neodiapsid this is completely different from the interpretations of the last 20 years which postulated that these paleoenvironments comprised monospecific associations of synapsid tracks these ichnoassociations are instead moderately diverse similar to low latitude marginal marine to floodplain ichnoassociations and belong to the lopingian paradoxichnium footprint biochron the cornberg formation of germany being constrained between the illawarra reversal and the mid wuchiapingian kupferschiefer at the rotliegend zechstein transition constitutes the earliest evidence of lopingian tetrapod faunas at low paleolatitudes and the first evidence of low paleolatitude faunal turnover related to the end guadalupian mass extinction from both the skeleton and the track record this suggests a global extension of the dinocephalian extinction event which occurred at high mid south africa and russia and low western europe paleolatitudes of pangea about 259 260 ma and was probably triggered by the eruption of the emeishan large igneous province of sw china which considerably changed global environmental conditions in both marine and continental settings

ecospace utilization paleoenvironmental trends and the evolution of early nonmarine biotas paleozoic nonmarine trace fossils evidence paleoenvironmental trends that are linked directly to progressive ecospace utilization spatial and functional these trends resulted in a considerable increase of ichnodiversity throughout the paleozoic colonization of nonmarine settings began as early as the late ordovician as recorded by the presence of terrestrial burrow systems associated with ancient soils in the other cases the presence of nonmarine trace fossils in cambrian and ordovician sedimentary rocks was the result of temporary colonization by marginal marine organisms and does not reflect establishment of true fresh water faunas devonian trace fossils have been reported from alluvial and alluvial lacustrine transitional environments surface arthropod trackways are dominant in marginal lake settings representing the development of true nonmarine biotas the presence of vertical burrows in fluvial deposits records the establishment of deep suspension feeding infaunal organisms trace fossils from the carboniferous reflect migration farther into the lakes ichnofossils have been reported from shallow and deep lake deposits and from alluvial and alluvial lacustrine transitional environments lake assemblages are dominated by surface grazing trails the permian was characterized by the establishment of a deep deposit feeding infauna commonly recorded by the scovenia ichnofacies represented by backfilled meniscate burrows

a new earthworm trace fossil from paleosols aestivation chambers from the late pleistocene sopas formation of uruguay a new ichnotaxon attributed to earthworm aestivation chambers is described from paleosols of the sopas formation upper pleistocene of northern uruguay this ichnofossil consists of a spherical chamber with a constructed wall of imbricated faecal pellets and a filling of rounded to meniscate pellets arranged in winding strings the strings may also be connected to specimens of taenidium serpentinum in the paleosol resulting in a compound trace fossil castrichnus incolumis igen et isp nov is interpreted as an earthworm aestivation chamber based on its morphological similarity to the chambers produced by extant earthworms as such c incolumis is considered an indicator of subaerial exposure and also of seasonal climate c incolumis is the second trace fossil that can be attributed with certainty to earthworms in addition the castrichnus t serpentinum compound specimens indicate that in paleosols earthworms can be the producers of t serpentinum aestivation chambers would represent a new ethological category

ichnology paleosols and palimpsests surfaces in the tinat member of the nuayyim formation unayzah group subsurface saudi arabia trace fossils and genetic stratigraphy in continental settings abstract the nuayyim formation of the unayzah group is widespread in subsurface central saudi arabia and constitutes a laterally variable stratigraphic unit with a complex mosaic of facies sedimentation for the tinat member took place majorly in a continental setting dominated by aeolian processes that resulted in dunes interdunes ephemeral stream deposits terminating with regional development of paleosols facies ichnofacies and palynological analysis suggest an arid to semi arid setting with biogenic activity in the form of continental fauna and plants in deposits associated with pedogenetical alteration in paleosol horizons therein burrowing exhibits elements of the scoyenia ichnofacies in beds with sparse to abundant bioturbation tectonic uplift and subaerial exposure resulted in the exhumation of previously buried substrates leading to the formation of burrowed palimpsests surfaces associated with paleosols at the end of unayzah deposition prior to the onset of the khuff formation progressive thermal updoming is interpreted to have occurred during the latest portion of the unayzah group sedimentation cycle in the arabian plate culminating in the regional pre khuff unconformity at the top of this megacycle recognized in this study by biogenically demarcated diastems ichnological and sedimentological observations outlined in this study are significant because they i refine existing interpretations of the paleoenvironmental history in the study area ii document diastems marking breaks in sedimentation and iii outline several soil forming cycles that allowed the establishment of a trace fossil suite with continental affinities thus demarcating the end of an entire sedimentation cycle the recognition and delineation of burrowed horizons associated with paleosols provides a tool to understand the tectono stratigraphic evolution of similar successions in the rock record

surface deformation and coherence measurements of kilauea volcano hawaii from sir c radar interferometry the shuttle imaging radar c x synthetic aperture radar sir c x sar radar on board the space shuttle endeavor imaged kilauea volcano hawaii in april and october 1994 for the purpose of measuring active surface deformation by the methods of repeat pass differential radar interferometry observations at 24 cm l band and 5 6 cm c band wavelengths were reduced to interferograms showing apparent surface deformation over the 6 month interval and over a succession of 1 day intervals in october a statistically significant local phase signature in the 6 month interferogram is coincident with the pu u o o lava vent interpreted as deformation the signal implies centimeter scale deflation in an area several kilometers wide surrounding the vent peak deflation is roughly 14 cm if the deformation is purely vertical centered southward of the pu u o o caldera delays in the radar signal phase induced by atmospheric refractivity anomalies introduce spurious apparent deformation signatures at the level of 12 cm peak to peak in the radar line of sight direction though the phase observations are suggestive of the wide area deformation measured by global positioning system gps methods the atmospheric effects are large enough to limit the interpretation of the result it is difficult to characterize centimeter scale deformations spatially distributed over tens of kilometers using differential interferometry without supporting simultaneous spatially distributed measurements of refractivity along the radar line of sight studies of the interferometric correlation of images acquired at different times show that l band is far superior to c band in the vegetated areas even when the observations are separated by only 1 day these results imply longer wavelength instruments are more appropriate for studying surfaces by repeat pass observations

early jurassic batrachopus rich track assemblages from interdune deposits in the wingate sandstone dolores valley colorado usa abstract late triassic and early jurassic tetrapod track assemblages are abundant and quite well documented from the respective chinle and glen canyon groups of the dolores valley region of western colorado and adjacent regions especially eastern utah however gaps still exist in our knowledge of the spatial and temporal distribution of representative ichnogenera the stratigraphic distribution of track assemblages in the cliff forming wingate sandstone formation the lower unit of the glen canyon group underlying the kayenta and navajo formations is difficult to determine because almost all wingate assemblages are known only from fallen blocks originating from precipitous vertical cliffs which yield both dune and interdune ichnofaunas among the characteristic lower jurassic biochron ichnogenera grallator eubrontes otozoum anomoepus and batrachopus in the dolores valley only grallator is known abundantly while otozoum and batrachopus were previously known only from single occurrences and eubrontes and anomoepus have yet to be reported we here report two large batrachopus rich assemblages that give new insight into the interdune paleoenvironments frequented by the batrachopus trackmaker traditionally regarded as a basal crocdylomorph and the theropodan trackmaker of grallator both assemblages contain the best preserved and most abundant batrachopus currently known locally in high densities where individual trackways are clearly visible they indicate that the trackmakers had variable gaits a third new assemblage containing batrachopus from salt creek is also described as is a fourth new assemblage from the uncompahgre plateau which yields moderately large theropod tracks cf eubrontes but no batrachopus although diagnostic late triassic biochron ichnogenera like brachychirotherium occur in basal units of the wingate sandstone batrachopus which is considered an early jurassic biochron ichnotaxon occurs within the formation thus vertebrate ichnotaxa help place the triassic jurassic boundary within the wingate formation shed light on their spatio temporal distribution and underscore their utility for paleoecological interpretation in a unit devoid of tetrapod body fossils

a new ichnotaxon classification of large mammaliform trackways from the lower cretaceous botucatu formation parana basin brazil abstract during the early cretaceous a large area in brazil and other south american countries was covered by an extensive paleoerg field the botucatu desert the araraquara county sao paulo state brazil contains some of the most diverse ichnological assemblages in the botucatu formation mammaliform trace fossils from the botucatu formation are of great interest as they may represent the only record of lower cretaceous mammaliamorpha from brazil these trace fossils can be grouped into two distinct classes based on the dimensions of the footprints the larger morphotype is described and classified as a new ichnotaxon aracoaraichnium leonardii igen nov isp nov with a discussion of preservational features and paleoecological aspects this morphotype can be differentiated from brasilichnium leonardi 1981 by digit morphology with digits iii and iv being larger and sub equal in size the tracks are mesaxonic unlike brasilichnium which is ectaxonic and the stride is proportionally smaller suggesting a trackmaker with shorter limbs in relation to body length another characteristic that reinforces the new ichnotaxon is the larger size of the footprints of aracoaraichnium igen nov footprints representing intermediate ontogenetic stages between brasilichnium and the larger morphotype are not observed suggesting that the two track types were made by different taxa compared with others tetrapod ichnotaxa the new ichnotaxon is characterized by differences in the number and morphology of the digits track morphology the degree of heteropody and locomotor parameters tracks with good preservation quality were likely originally produced in the humid subsurface below the surficial dry sand layer tracks with smaller dimensions and trackways with the presence or absence of the manus may be due to variable degrees of impression into subsurface layers and substrate heterogeneity the aracoaraichnium igen nov trackmakers probably inhabited areas near the desert making occasional incursions into desert areas while brasilichnium trackmakers may have been mostly nocturnal residents of the desert environment

trace fossils as paleoenvironmental indicators in the taylor group devonian of antarctica abstract the taylor group of southern victoria land antarctica contains varied and abundant trace fossils which have been interpreted by palaeontologists as indicating marine deposition however sedimentologists have largely favoured non marine deposition on the basis of desiccation polygons fining upward cycles unidirectional paleocurrents small channels red beds and paleosols the debate is reconciled by a reinterpretation of the trace fossil assemblage it is shown that widespread and well preserved cruziana diplichnites rusophycus and skolithos which have previously been used as marine indicators comprise an ichnofacies scoyenia which is entirely typical of fresh water

giant desiccation fissures filled with calcareous eolian sand hermosa formation pennsylvanian southeastern utah abstract at two stratigraphic intervals within the upper member of the upper pennsylvanian hermosa formation calcareous eolian sand fills downward tapering fissures that are as much as 18 cm wide and 5 7 m deep fissure fillings define orthogonal polygons 10 m or more in diameter one of the host beds is primarily composed of subtidally deposited limestone the other is a thinly laminated nonmarine red siltstone both systems of fissure fillings are directly overlain and underlain by large scale cross stratified calcareous eolianites the limestone host bed contains chert pseudomorphs after gypsum compaction of host rocks contorted fissure fillings and caused doming of eolian strata over each fissure platy mineral grains in fissure fillings are aligned subparallel to bedding in the host rocks supporting the view that the fissures were passively filled rather than forcefully injected these ancient fissure systems are similar in scale and pattern to those that define giant desiccation polygons in numerous great basin playas the pennsylvanian fissures like their holocene counterparts probably formed when groundwater tables dropped from shallow levels within fine grained impermeable deposits into underlying aquifers greatly decreasing the extent of the capillary fringe our study of the fissures and host rocks supports the hypothesis that carbonate grains within the eolianites were deflated from uncemented marine sediments that were broadly exposed during regressive intervals

megarhizoliths in pleistocene aeolian deposits from gran canaria spain ichnological and palaeoenvironmental significance the pleistocene dune field of tufia located on the east of gran canaria spain contains different stratigraphic levels of indurated pillar like structures that are interpreted as megarhizoliths the megarhizoliths occur at the top of different aeolian sets and reach 31 5 cm in diameter and over 1 m in height these scattered free standing vertical cylindrical to slightly conical columns usually appear as hollow cylinders displaying elliptical cross sections aligned with the prevailing wind on the leeward side of some specimens the external wall shows a tail of rock matrix resembling a sort of wind shadow these tails and other remains of the associated rock matrix show a texture composed of long horizontal parallel cylinders orientated with the wind internally the most complete structures show five concentrically arranged zones zone a is a central pore corresponding to the cavity originally occupied by the root zones b and c which include alveolar and laminated carbonate textures indicating that carbonate precipitation was mostly induced by the roots and their associated microorganisms and zones d and e consisting mostly of aeolian sands in d the sand grains show thin micritic coatings whereas in e vadose aragonite cements can be seen on the grain surface suggesting a less biogenic influence in their formation the degree of cementation and the time of the precipitation of carbonate around the roots controlled the preservation of these zones thus in some cases zones b c and or d are not preserved cylinders are up to 30 the diameter of the root that nucleated them the presence of the megarhizoliths at the top of the aeolianite beds indicates that aeolian sedimentation halted several times allowing soil formation and plant colonisation during slightly more humid periods the occurrence of megarhizoliths is further proof of the alternation of arid and slightly more humid climates in the north atlantic during the last glacial period it is also noted that they may be misinterpreted as animal trace fossils or tree trunk casts resulting in incorrect ichnological or palaeoenvironmental interpretations

using dinsar airborne lidar and archival air photos to quantify landsliding and sediment transport 1 we demonstrate the ability of coupled remote sensing tools to characterize large slow moving landslides in the eel river catchment northern california from a stack of alos interferograms we identified 5 large 1 km long landslides that exhibited significant activity from february 2007 to february 2008 for the boulder creek earthflow we used orthorectified air photos taken in 1964 and unfiltered airborne lidar flown in 2006 to map the displacement of trees growing on the landslide surface combining those displacement orientations with stacked dinsar data we observed average downslope velocities of 0 65 m yr 1 through the central transport zone of the landslide given landslide depth estimates minimum sediment transport and denudation rates are estimated to be 4100 m3 yr 1 and 1 6 mm yr 1 respectively our results demonstrate the highly erosive role of large slow moving landslides in landscape evolution and suggest that the superposition of dense ephemeral gully networks and rapidly moving zones within the landslide may facilitate delivery of slide mobilized sediment into adjacent fluvial channels

fossil vertebrate footprints in the coconino sandstone permian of northern arizona evidence for underwater origin numerous fossil vertebrate trackways in the coconino sandstone of northern arizona exhibit several features that imply that these trackways were not made in subaerial conditions some trackways begin or end abruptly on undisturbed bedding planes and in other trackways the individual prints are oriented in a different direction from that of the trackway these features indicate buoyancy of the animals in water the animals were swimming in the water part of the time and at other times walking on the substrate and they were sometimes orienting upslope on the surface of the underwater dunes while being drifted sideways by lateral currents observations on salamander locomotion in a sedimentation tank with flowing water support this model

monitoring of land subsidence and ground fissures in xian china 2005 2006 mapped by sar interferometry the city of xian china has been experiencing significant land subsidence and ground fissure activities since 1960s which have brought various severe geohazards including damages to buildings bridges and other facilities monitoring of land subsidence and ground fissure activities can provide useful information for assessing the extent of and mitigating such geohazards in order to achieve robust synthetic aperture radar interferometry insar results six interferometric pairs of envisat asar data covering 2005 2006 are collected to analyze the insar processing errors firstly such as temporal and spatial decorrelation error external dem error atmospheric error and unwrapping error then the annual subsidence rate during 2005 2006 is calculated by weighted averaging two pairs of d insar results with similar time spanning lastly gps measurements are applied to calibrate the insar results and centimeter precision is achieved as for the ground fissure monitoring five insar cross sections are designed to demonstrate the relative subsidence difference across ground fissures in conclusion the final insar subsidence map during 2005 2006 shows four large subsidence zones in xian hi tech zones in western eastern and southern suburbs of xian city among which two subsidence cones are newly detected and two ground fissures are deduced to be extended westward in yuhuazhai subsidence cone this study shows that the land subsidence and ground fissures are highly correlated spatially and temporally and both are correlated with hi tech zone construction in xian during the year of 2005 2006

humans as geologic agents a deep time perspective humans move increasingly large amounts of rock and sediment during various construction activities and mean rates of cropland soil loss may exceed rates of formation by up to an order of magnitude but appreciating the actual importance of humans as agents of global erosion necessitates knowledge of prehistoric denudation rates imposed on land surfaces solely by natural processes amounts of weathering debris that compose continental and oceanic sedimentary rocks provide one such source of information and indicate that mean denudation over the past half billion years of earth history has lowered continental surfaces by a few tens of meters per million years in comparison construction and agricultural activities currently result in the transport of enough sediment and rock to lower all ice free continental surfaces by a few hundred meters per million years humans are now an order of magnitude more important at moving sediment than the sum of all other natural processes operating on the surface of the planet relationships between temporal trends in land use and global population indicate that humans became the prime agents of erosion sometime during the latter part of the first millennium a d

synapsid burrows and associated trace fossils in the lower jurassic navajo sandstone southeastern utah u s a indicates a diverse community living in a wet desert ecosystem abstract enigmatic structures in the lower jurassic navajo sandstone near moab utah occur at three localities below carbonate beds that record interdune lake deposits these structures are interpreted as mammal and therapsid burrows based on their architectural and surficial burrow morphologies type i large diameter and type ii mega diameter burrows type i burrows include sinuous tunnels y and t branched tunnels sinuous ramps and chambers and weather into mounds averaging 33 m 22 m and extend 1m above the surface type i burrows are dorsoventrally flattened in cross section averaging 9 3 cm wide and 4 2 cm high and are sand filled and structureless type i burrows mostly have smooth walls though some have scalloped walls type ii burrows are simple inclined tunnels 35 cm wide and 20 cm high and exhibit well preserved bilobate morphology along the underside of the tunnel the walls preserve a series of 3 or 4 thin 4 8 mm inclined scratch marks from the upper part of the wall and along the floor the great complexity and high density of type i burrow systems is best explained by multiple individuals living together in social groups these burrows are more complex than early triassic therapsid burrows from south africa and are most similar to burrows of extant social e g voles and eusocial mammals e g naked mole rats type ii burrows were likely constructed by therapsids based on burrow size and comparison to permian and triassic therapsid burrows from south africa and antarctica

ichnotaxonomy and ichnostratigraphy of chambered trace fossils in palaeosols attributed to coleopterans ants and termites

archean to recent aeolian sand systems and their sedimentary record current understanding and future prospects the sedimentary record of aeolian sand systems extends from the archean to the quaternary yet current understanding of aeolian sedimentary processes and product remains limited most preserved aeolian successions represent inland sand sea or dunefield erg deposits whereas coastal systems are primarily known from the cenozoic the complexity of aeolian sedimentary processes and facies variability are under represented and excessively simplified in current facies models which are not sufficiently refined to reliably account for the complexity inherent in bedform morphology and migratory behaviour and therefore cannot be used to consistently account for and predict the nature of the preserved sedimentary record in terms of formative processes archean and neoproterozoic aeolian successions remain poorly constrained palaeozoic ergs developed and accumulated in relation to the palaeogeographical location of land masses and desert belts during the triassic widespread desert conditions prevailed across much of europe during the jurassic extensive ergs developed in north america and gave rise to anomalously thick aeolian successions cretaceous aeolian successions are widespread in south america africa asia and locally in europe spain and the usa several eocene to pliocene successions represent the direct precursors to the present day systems quaternary systems include major sand seas ergs in low lattitude and mid latitude arid regions pleistocene carbonate and holocene modern siliciclastic coastal systems the sedimentary record of most modern aeolian systems remains largely unknown the majority of palaeoenvironmental reconstructions of aeolian systems envisage transverse dunes whereas successions representing linear and star dunes remain under recognized research questions that remain to be answered include i what factors control the preservation potential of different types of aeolian bedforms and what are the characteristics of the deposits of different bedform types that can be used for effective reconstruction of original bedform morphology ii what specific set of controlling conditions allow for sustained bedform climb versus episodic sequence accumulation and preservation iii can sophisticated four dimensional models be developed for complex patterns of spatial and temporal transition between different mechanisms of accumulation and preservation and iv is it reasonable to assume that the deposits of preserved aeolian successions necessarily represent an unbiased record of the conditions that prevailed during episodes of earth history when large scale aeolian systems were active or has the evidence to support the existence of other major desert basins been lost for many periods throughout earth history

stratigraphic evolution and preservation of aeolian dune and damp wet interdune strata an example from the triassic helsby sandstone formation cheshire basin uk new and previously published models of wet aeolian system evolution form a spectrum of types that may be explained in terms of aeolian dune dynamics rate of water table rise and or periodicity of interdune flooding this is illustrated with an example from the mid triassic anisian helsby sandstone formation cheshire uk lenses of damp and wet interdune strata exhibit an intertonguing transitional relationship with the toe sets of overlying aeolian dune units this signifies dune migration that was contemporaneous with water table controlled accumulation in adjacent interdunes downwind changes in the geometry and facies of the interdune units indicate periodic expansion and contraction of the interdunes in response to changes in the elevation of the groundwater table and episodic flooding during which accumulation of dune strata continued relatively uninterrupted this contrasts with other models for accumulation in wet aeolian systems where interdune flooding is associated with a cessation in aeolian bedform climbing and the formation of a bypass or erosional supersurface architectural panels document the detailed stratigraphy in orientations both parallel and perpendicular to aeolian transport direction enabling a quantitative three dimensional reconstruction of genetically related aeolian dune and interdune elements sets of aeolian dune strata are composed of grainflow and translatent wind ripple strata and are divided by a hierarchy of bounding surfaces originating from oblique migration of superimposed dunes over slipfaceless sinuous crested parent bedforms together with lee slope reactivation under non equilibrium flow conditions silty mudstone and sandstone interdune units are characterized by wind ripple wavy and subaqueous wave ripple laminae desiccation cracks mud flakes raindrop imprints load casts flutes intraformational rip up clasts and vertebrate and invertebrate footprint impressions and trackways these units result from accumulation on a substrate that varied from dry through damp to wet surface conditions interdune ponds were flooded by either fluvial incursions or rises in groundwater table and were periodically subject to gradual desiccation and reflooding red silty mudstone beds of subaqueous origin pass laterally into horizontally laminated wind ripple beds indicating a progressive transition from wet through damp to dry surface conditions within a single interdune

first steps on land arthropod trackways in cambrian ordovician eolian sandstone southeastern ontario canada basal terrestrial deposits in the cambrian ordovician nepean formation potsdam group near kingston ontario contain arthropod produced trackways that extend the record of the first arthropod landfall back by as much as 40 m y the presence of large simple cross beds and of wind produced structures including adhesion ripples and wind ripple lamination indicates that the host strata were deposited in an eolian dune field probably in a marginal marine setting the trackways were preserved mainly as undertracks and record the activities of large amphibious arthropods possibly euthycarcinoids

time dependent land uplift and subsidence in the santa clara valley california from a large interferometric synthetic aperture radar data set 1 we invert 115 differential interferograms derived from 47 synthetic aperture radar sar scenes for a time dependent deformation signal in the santa clara valley california the time dependent deformation is calculated by performing a linear inversion that solves for the incremental range change between sar scene acquisitions a nonlinear range change signal is extracted from the ers insar data without imposing a model of the expected deformation in the santa clara valley cumulative land uplift is observed during the period from 1992 to 2000 with a maximum uplift of 41 18 mm centered north of sunnyvale uplift is also observed east of san jose seasonal uplift and subsidence dominate west of the silver creek fault near san jose with a maximum peak to trough amplitude of 35 mm the pattern of seasonal versus long term uplift provides constraints on the spatial and temporal characteristics of water bearing units within the aquifer the silver creek fault partitions the uplift behavior of the basin suggesting that it acts as a hydrologic barrier to groundwater flow while no tectonic creep is observed along the fault the development of a low permeability barrier that bisects the alluvium suggests that the fault has been active since the deposition of quaternary units

integrated ichnofacies models for deserts recurrent patterns and megatrends abstract although it is commonly assumed that the trace fossil record of eolian dunes and associated environments is invariably poor a systematic review of the available information indicates that this is not necessarily the case a model involving five main phases of colonization of desert environments through the phanerozoic is proposed in this paper the first phase cambrian silurian involved animal incursions into coastal dune fields directly from the sea although it is unlikely that these animals would have remained for long periods of time in coastal deserts the second phase devonian reflects the activities of dune pioneers that left their fluvial habitat to enter temporary or permanently into inland deserts the third phase carboniferous permian involved the colonization of deserts by tetrapods the fourth phase triassic cretaceous involved a major exploitation of the infaunal ecospace as reflected by the appearance of more varied behavioral patterns in sub superficial structures the fifth phase paleogene recent reflects the appearance of the ecological dynamic that characterizes modern desert communities the invertebrate ichnofacies for eolian dunes is re named herein as the octopodichnus entradichnus ichnofacies honoring the seminal work of previous workers who simultaneously tackled the issue of eolian dune ichnofacies the chelichnus ichnofacies is retained for vertebrate trace fossil assemblages in eolian settings both ichnofacies occur in mobile and temporary stabilized sandy substrates subject to frequent erosion and deposition and to strong seasonality desert settings consist of complex mosaics of habitats or physical units associated with organism activity trace fossil distribution can be understood as reflecting the partitioning of desert settings in a mosaic of landscape units characterized by water content and its temporal fluctuations nutrient availability nature of the substrate and the dominant organisms present in turn desert systems are dynamic entities that change as a response to regional climate landscape units such as eolian sand seas salt flat and playa lake systems ephemeral rivers and alluvial fans interact in response to regional scale climate variations in hyper arid arid and semiarid climatic settings ancient deserts completely developed under hyper arid climatic conditions rarely preserve trace fossils due to the absence of moisture near the surface however the alternation of wet periods may represent windows for life development and thus preservation of biogenic structures arid deserts display complex patterns of dunes combined with dry wet and flooded interdunes dry desert elements e g dunes interdunes sand sheets typically record the entradichnus octopodichnus and chelichnus ichnofacies slight rises in regional precipitation produce elevation of the water table and increase of fluvial discharges that provide water and sediment to the system these processes may result in the local concentration of trace fossils in wet interdunes and ephemeral fluvial systems illustrating the scoyenia and chelichnus ichnofacies in semiarid systems playa lakes expand by the addition of freshwater evolving into freshwater lakes and fluvial systems may become more common lake margins and fluvial overbanks typically contain trace fossil assemblages that may be ascribed to the scoyenia ichnofacies

late miocene ground sloth footprints and their paleoenvironment megatherichnum oportoi revisited abstract fossil footprints of ground sloths are mostly restricted to the late miocene to pleistocene of south america this study is focused on the oldest known ground sloth trackways megatherichnum oportoi casamiquela 1974 from the late miocene rio negro formation of northern patagonia the section logged at the study site near carmen de patagones buenos aires province includes the uppermost part of the middle member marine and the upper member aeolian of the rio negro formation identified sedimentary facies can be grouped into four facies associations tidal flat aeolian dune dry damp interdune and wet interdune shallow lacustrine m oportoi trackways are preserved in an upper intertidal mixed flat associated trace fossils belong to a wet aeolian system developed close to the sea coast and were mostly preserved in interdune facies these include poaceae root and stem traces and nagtuichnus meuleni chlamyphorinae burrow in dry interdune facies indeterminate tetrapod footprints in damp interdune facies lockeia siliquaria and chevron like trace fossils bivalve resting and horizontal locomotion traces in wet interdune facies shallow lakes and palaeophycus tubularis in aeolian dune facies the most likely trackmaker of m oportoi is pyramiodontherium sp megatheriinae recorded from the same stratigraphic unit at chubut province with a body mass ranging from 2 5 to 3 6 t m oportoi is interpreted as a quadrupedal trackway of a late miocene ground sloth without overlap of the pes on the manus the previously proposed bipedal interpretation for the trackway requires angles of gait in excess of those permitted for such a large and heavy animal pleistocene ground sloth trackways are distinctive because of the much smaller size of the fore footprint for the latter examples a quadrupedal locomotion with overlap of the pes on the manus may be applied

an examination of seasonal deformation at the portuguese bend landslide southern california using radar interferometry 1 the portuguese bend landslide located on the palos verdes peninsula in southern california is a slow moving landslide whose activity is closely tied to infiltration from rainfall we use radar interferometry to constrain the seasonal kinematics of the landslide from 1995 to 2000 traditional interferometric synthetic aperture radar methods estimate an average downslope displacement rate of 1 00 m yr with an uncertainty range of 0 39 2 57 m yr during the summer months interferograms show a consistent loss in phase coherence over the landslide for epochs greater than 6 months especially in the winter interferograms become incoherent as a result of large displacement and decorrelation is used to map the spatial extent of slide movement through time the displacement rate increases sharply several weeks after the beginning of the rainy season as rainwater percolating into the slide elevates pore pressures phase coherence is lost when the slide velocity surpasses 2 6 m yr for interferograms with durations of a few months a physically based model based on rainfall driven landslide movement incorporates these observations to constrain hydraulic diffusivity to between 0 9 and 3 5 10 6 m2 yr

the shorebird ichnofacies an example from the miocene of southern spain the late miocene sorbas member of the sorbas basin almeria province southeast spain contains an extensive avian ichnofauna preserved in lagoonal marls three distinctive avian ichnotaxa can be identified antarctichnus fuenzalidae covacevich and lamperein 1970 iranipeda millumi n ichnosp and roepichnus grahami n ichnogen n ichnosp in common with many other cenozoic avian ichnofaunas these traces are associated with shorebirds including plovers storks ducks and or gulls respectively associated mammalian tracks include possible cat and artiodactyl footprints the avian tracks are abundant and show a range of behavioural aspects in common with other recorded examples of cretaceous recent shorebird tracks these include both solitary and group activities consistent with their postulated avian tracemakers

life and death in a late cretaceous dune field nemegt basin mongolia for more than 70 years red sandstones of the gobi desert have yielded abundant articulated skeletons of late cretaceous dinosaurs lizards and mammals at ukhaa tolgod structureless sandstones are the only fossiliferous facies and we present new evidence for deposition on dune sand sourced alluvial fans that were built at the margins of stabilized eolian bedforms during mesic climatic episodes in laterally and vertically adjacent large scale eolian cross strata in which skeletons are absent we have found abundant tracks of dinosaurs that walked on sparsely vegetated dunes that were active under xeric conditions our study of calcareous concretions in vaguely bedded eolian sandstones suggests that bedding was nearly destroyed by burrowing invertebrates and trampling dinosaurs the accumulation of illuvial clays and pedogenic calcite in these sediments reduced infiltration of rainwater and with attendant climatic change and heavy rainfall events led to fan development

tetrapod trackways from the early middle devonian period of poland the fossil record of the earliest tetrapods vertebrates with limbs rather than paired fins consists of body fossils and trackways the earliest body fossils of tetrapods date to the late devonian period late frasnian stage and are preceded by transitional elpistostegids such as panderichthys and tiktaalik that still have paired fins claims of tetrapod trackways predating these body fossils have remained controversial with regard to both age and the identity of the track makers here we present well preserved and securely dated tetrapod tracks from polish marine tidal flat sediments of early middle devonian eifelian stage age that are approximately 18 million years older than the earliest tetrapod body fossils and 10 million years earlier than the oldest elpistostegids they force a radical reassessment of the timing ecology and environmental setting of the fish tetrapod transition as well as the completeness of the body fossil record

the discovery of a new devonian tetrapod trackway in sw ireland a tetrapod trackway has been discovered in devonian sedimentary rocks of sw ireland it is the first discovery of its kind in europe details of the footprints are not preserved probably because of strong variscan pressure solution cleavage however after removing the effect of variscan deformation the large number of footprints more than 150 makes it possible to calculate the original dimensions of the footprint pattern stride approximately 34 cm and pace approximately 35 cm these values are higher than those for other traces of comparable age the total length of the tetrapod is estimated to be 1 m lithostratigraphical and biostratigraphical arguments indicate an age of mid to late devonian

tetrapod track assemblages from lower cretaceous desert facies in the ordos basin shaanxi province china and their implications for mesozoic paleoecology tetrapod ichnofaunas are reported from desert playa lake facies in the lower cretaceous luohe formation at baodaoshili shaanxi province china which represent the first asian example of an ichnnofauna typical of the chelichnus ichnofacies brasilichnium sub ichnofacies characteristic of desert habitats the mammaliomorph tracks assigned to brasilichnium represent the first report of this ichnogenus from asia the assemblages also contain three different theropod trackway morphotypes one very wide magnoavipes like morphotype one relatively wide broad toed small eubrontes like form with short steps and strides and wide straddle and an elongate morphotype sarmientichnus with longer steps and narrower straddle representing a didactyl trackmaker the latter being the first example of the enigmatic ichnogenus found outside its type area in argentina the sarmientichnus occurrence the first in asia has important implications demonstrating that the trackmaker was not monodactyl but didactyl with probable affinities to deinonychosaurians which are ichnologically well represented in the lower cretaceous of asia although morphologically distinctive sarmientichnus should be recognized as a form ichnotaxon compromised by suboptimal preservation the combination of brasilichnium isp sarmientichnus isp and tridactyl theropod tracks indicates mammaliomoprhs and small theropods and is comparable to ichnofaunas from similar desert facies on other continents thus cretaceous desert ichnofaunas from china are consistent with global ichnofacies predictions

temporal analysis of a landslide by means of a ground based sar interferometer a ground based synthetic aperture radar gb sar interferometer is used to retrieve the velocity field of a landslide high resolution images are obtained by means of a time domain sar processor an in depth analysis of the sequence of sar interferograms enables the recognition of a slowly deforming upper scarp in the scene and a debris flow that feeds the accumulation zone of the landslide where a fast change in terrain morphology is observed the estimated deformation map is in agreement with the available measurements obtained by means of global positioning system receivers results show that gb sar interferometry is a cost effective solution for the monitoring of landslides the proposed method is shown to be a valid complement to space and airborne sar and to the traditional geodetic instruments

applications of ichnology in lacustrine sequence stratigraphy potential and limitations abstract in comparison with their marine counterparts lacustrine ichnofaunas have not been extensively used in sequence stratigraphy application of trace fossils in continental sequence stratigraphy cannot be based simply on the extrapolation of marine sequence stratigraphy marine substrate controlled ichnofacies in particular the firmground glossifungites ichnofacies develop in stable and cohesive substrates reflecting erosive exhumation of the sediment in contrast in lacustrine sequences substrate controlled ichnofossils only rarely indicate erosional exhumation because they are commonly related to desiccation of water bodies the tripartite division of overfilled balanced fill and underfilled lakes provides a comprehensive framework to evaluate the potential and limitations of lacustrine ichnofaunas in sequence stratigraphy based on a number of case studies spanning the three lake basin types a model of trace fossil distribution in overfilled balanced fill and underfilled basins is proposed overfilled lake basins contain well developed softground trace fossils mermia and skolithos ichnofacies and the softground suite of the scoyenia ichnofacies that are useful to delineate parasequences and parasequence sets fluvial discharge into overfilled lakes usually generates density currents that oxygenate lake bottoms allowing the establishment of epifaunal and infaunal communities additionally these are freshwater lakes where no stress due to hypersalinity occurs leading to the development of a relatively diverse benthos land plant derived organic matter is the prime source of nutrients favoring the development of a deposit feeding benthic fauna in permanently subaqueous low energy zones firmground suites are rare because such large lakes usually do not experience desiccation abundant firmground trace fossil suites of the scoyenia ichnofacies occur in balanced fill lakes but softground assemblages are usually depauperate lowstand deposits contain abundant and widespread ichnofaunas commonly meniscate trace fossils and arthropod trackways of the scoyenia ichnofacies lake hydrology is closed during lowstands and salinity usually increases imposing a stress factor on the lake biota and therefore softground ichnofaunas are depauperate ichnofaunas from turbidite systems in balanced fill lakes are less abundant and diverse than those from overfilled lacustrine turbidites freshwater conditions are common during transgression but dysaerobic conditions may prevail imparting a stress factor on the benthic biota in hydrologically closed lakes the scoyenia ichnofacies is widespread but the mermia ichnofacies is commonly absent or impoverished the scoyenia ichnofacies is associated with lowstand desiccated substrates in underfilled lakes the density of arthropod trackways may be high forming tracked omission surfaces some of these omission surfaces may represent sequence boundaries expressed by co planar surfaces of lowstand and subsequent flooding rapid changes in depositional conditions reflecting desiccation during vertical aggradation can lead to the formation of composite ichnofabrics that reflect successive bioturbation events

episodic deposition and preservation of eolian sands a late paleozoic example from southeastern utah the upper pennsylvanian and lower permian stratigraphic sequence in canyonlands national park contains about 40 flat topped eolian sand bodies rhizoliths burrows and traces of former evaporites abound at the tops of these tabular genetic units upper surfaces of units were created by eolian deflation to the level of the groundwater table analysis of cross stratification reveals that sands accumulated via migration and climb of relatively small dunes brief episodes of sand accumulation were triggered by regression and were terminated when upwind sand supplies were depleted upper surfaces of genetic units are diastems and represent much more geologic time than the rocks themselves

last interglacial fossil elephant trackways dated by osl aar in coastal aeolianites still bay south africa abstract the impressive pleistocene coastal aeolianite exposures in sea cliffs east of still bay on the west southern coast of south africa host a rich archive of fossil mammalian trackways including the african elephant loxodonta africana neither the ichnofossils nor their host sediments have been described in any detail and chronologies remained uncertain this paper presents a new optically stimulated luminescence osl and amino acid racemisation aar chronology the first joint application of osl aar dating in south africa this provides a temporal framework for assessing the palaeoenvironmental significance of dune sedimentation patterns pedogenesis and ichnology the pleistocene aeolianite exposures at still bay represent the recently eroded remnants of a dune cordon mainly built by coalesced parabolic dune systems sedimentary facies are dominated by large scale planar cross stratification formed by foreset progradation in the nose and trailing arms of the dunes and low angle bedding chiefly representing sedimentation in low relief interdune terrain the main dune building wind regime was westerly associated with cyclonic polar frontal systems as at the present time the osl and aar dating demonstrate ages ranging from mis 5e to 5b and termination of pleistocene aeolian sedimentation at 90 ka the pleistocene aeolianite is separated from the overlying holocene dunes dated to 8 ka by a major hiatus recorded by a horizon of intense pedogenesis elephant footprints were seen in profile as casts on the underside of beds and as natural impressions the taphonomic processes controlling the morphology and preservation of these unique ichnofossils were found to be complex the presence of loxodonta africana at still bay represents the southernmost occurrence of this species recorded to date and possibly a closer proximity of woodland during mis 5 this and other observations may indicate a higher moisture regime than at present there is no available evidence that the elephants were predated by contemporary middle stone age people

preservation and erosion of theropod tracks in eolian deposits examples from the middle jurassic entrada sandstone utah u s a abstract the middle jurassic entrada sandstone exposed near the town of escalante southern utah consists of large scale cross bedded eolian deposits that are interbedded with horizontally laminated sand sheets and thin sets of eolian cross strata representing periods with a moister climate the flat bedded units contain numerous tracks and trackways from small to large sized theropod dinosaurs these tracks are today exposed in several distinct erosional states allowing detailed studies of track and undertrack formation in eolian deposits tracks that originally were emplaced on sloping surfaces show in their present day erosional state a morphology distinct from those originally emplaced on horizontal surfaces further the range of eroded track morphologies can help identify badly eroded tracks from nonbiogenic structures in similar deposits

on the application of sar interferometry to geomorphological studies estimation of landform attributes and mass movements this paper presents two examples of application of synthetic aperture radar sar interferometry insar to typical geomorphological problems the principles of insar are introduced taking care to clarify the limits and the potential of this technique for geomorphological studies the application of insar to the quantification of landform attributes such as the slope and to the estimation of landform variations is investigated two case studies are presented a first case study focuses on the problem of measuring landform attributes by interferometric sar data the interferometric result is compared with the corresponding one obtained by a digital elevation model dem in the second case study the use of insar for the estimation of landform variations caused by a landslide is detailed

possible burrows of mylagaulids rodentia aplodontoidea mylagaulidae from the late miocene barstovian pawnee creek formation of northeastern colorado abstract the massive siltstone beds of the late miocene barstovian pawnee creek formation in logan county northeastern colorado contain abundant terrestrial vertebrate burrows among these are distinctive claw marked burrows attributable to the extinct mylagaulid rodent pterogaulus mylagaulus laevis korth 2000 these burrows differ in several respects from the spiraling daemonelix burrows of fossorial beavers the pawnee creek burrows are slightly ovate in cross section tubular and sinuous rather than helical they consist of primary tunnels of up to at least 7 m long and range from 11 to 18 cm in diameter they occasionally branch into secondary tunnels burrow walls and terminations show prominent parallel ridges in sets of two to three up to 9 3 mm deep and 3 7 mm wide the burrows are too large to have been made by anything but a vertebrate and their considerable length and complexity implies a mammalian excavator the meandering branching morphology resembles the burrow systems of extant fossorial rodents such as pocket gophers geomys and mole rats spalax myospalax skeletal remains of p laevis are abundant at sites where the burrows occur with at least eight individuals represented by humeri in a collected sample although mylagaulid remains are not unequivocally associated with fossil burrows the curved laterally compressed claws and phalangeal arrangement of mylagaulids produce marks very similar in size and morphology to the ridges on the burrows position and pattern of the ridges indicate downward and backward motions of the mani possibly supplemented by motions of the pedes to kick loosened soil backward a new ichnogenus alezichnos and new ichnospecies chelecharatos are erected to describe these burrows

an integrative physical mineralogical and ichnological approach to characterize underfilled lake basins fil mancuso adriana cecilia consejo nacional de investigaciones cientificas y tecnicas centro cientifico tecnologico conicet mendoza instituto argentino de nivologia glaciologia y ciencias ambientales provincia de mendoza instituto argentino de nivologia glaciologia y ciencias ambientales universidad nacional de cuyo instituto argentino de nivologia glaciologia y ciencias ambientales argentina

biogenic structures produced by sand swimming snakes a modern analog for interpreting continental ichnofossils abstract a noichnological experiment using the kenyan sand boa eryx colubrinus reveals the diversity of biogenic structures produced by sand swimming vertebrates in unconsolidated sand documentation of these biogenic structures will aid in the identification and interpretation of similar ichnofossils in the geologic record and help improve paleoenvironmental and paleoecological reconstructions two sand boas and three sand filled chambers containing 1 3 cm thick layers of fine to medium grained sand were used in this burrowing experiment the burrowing activities of the snakes were observed over a 14 day period and the chambers were photographed regularly to record sediment disturbance eryx colubrinus produced a number of biogenic structures including 1 cone shaped downward tapering features 2 straight vertical tubes 3 elongate sinuous tunnels 4 semicircular concave divots 5 downward and upward deflected laminae and 6 offset laminae these different trace morphologies are present together forming a large compound ichnofossil resulting from locomotion resting and dwelling behaviors absent from the sand swimming biogenic structures were active backfill features open tunnels and burrow linings the recognition and interpretation of ichnofossils in the rock record of sand swimming vertebrates requires their association with assemblages of known terrestrial body and trace fossils rhizoliths and pedogenic fabrics given the ecology of extant sand swimming vertebrates their biogenic structures characterize loose sediments with low interstitial moisture and environments with arid to semiarid climates the biogenic structures produced in this experiment represent a new type of previously unrecognized biodiversity that of sand swimming vertebrates in order to understand the evolution of fossorial behavior in continental vertebrates recognition of the morphology of all types of interactions between vertebrates and the sediment must be considered

use of differential sar interferometry in monitoring and modelling large slope instability at maratea basilicata italy abstract differential synthetic aperture radar sar interferometry diffsar allows in principle to measure very small movements of the ground and to cover in continuity large areas so that it can be considered as a potentially ideal tool to investigate landslides and other slope instability in this paper we explore the use of this technique to improve our knowledge of the slope instability of a well investigated area the maratea valley affected by continuous slow movements producing an impressive sackung type phenomenon which poses several unanswered questions in particular by using this technique we analyse the time evolution of ground movements from 1997 to 2000 the slope movements during this same time interval have also been monitored in the past by using other techniques such as electronic distance meter edm and gps measurements gps and diffsar results are here compared in our implementation of the diffsar technique the problem of decorrelation noise is faced by using a phase unwrapping approach that allows to process sparse data and the impact of atmospheric artefacts is reduced by performing a temporal analysis of the deformations observed in successive interferograms in this study we also show that it is possible to perform a temporal analysis of continuous slow landslide movements by using a limited number of ers sar data sets and low precision topographic information all the acquired data edm gps and diffsar are consistent and allow a kinematic model of instability within the investigated time interval to be proposed a map of slopes subject to different velocities of vertical displacements was delineated modifying previous knowledge within the valley progressive and almost linear displacements over time were confirmed

styles of interaction between aeolian fluvial and shallow marine environments in the pennsylvanian to permian lower cutler beds south east utah usa the pennsylvanian to permian lower cutler beds comprise a 200 m thick mixed continental and shallow marine succession that forms part of the paradox foreland basin fill exposed in and around the canyonlands region of south east utah aeolian facies comprise i sets and compound cosets of trough cross bedded dune sandstone dominated by grain flow and translatent wind ripple strata ii interdune strata characterized by sandstone siltstone and mudstone interbeds with wind ripple wavy and horizontal planar laminated strata resulting from accumulation on a range of dry damp or wet substrate types in the flats and hollows between migrating dunes and iii extensive near flat lying wind rippled sandsheet strata fluvial facies comprise channel fill sandstones lag conglomerates and finer grained overbank sheet flood deposits shallow marine facies comprise carbonate ramp limestones tidal sand ridges and bioturbated marine mudstones during episodes of sand sea construction and accumulation compound transverse dunes migrated primarily to the south and south east whereas south westerly flowing fluvial systems periodically punctuated the dune fields from the north east several vertically stacked aeolian sequences are each truncated at their top by regionally extensive surfaces that are associated with abundant calcified rhizoliths and bleaching of the underlying beds these surfaces record the periodic shutdown and deflation of the dune fields to the level of the palaeo water table during episodes of aeolian quiescence fluvial systems became more widespread forming unconfined braid plains that fed sediment to a coastline that lay to the south west and which ran approximately north west to south east for at least 200 km shallow marine systems repeatedly transgressed across the broad low relief coastal plain on at least 10 separate occasions resulting in the systematic preservation of units of marine limestone and calcarenite between units of non marine aeolian and fluvial strata to form a series of depositional cycles the top of the lower cutler beds is defined by a prominent and laterally extensive marine limestone that represents the last major north eastward directed marine transgression into the basin prior to the onset of exclusively non marine sedimentation of the overlying cedar mesa sandstone styles of interaction between aeolian fluvial and marine facies associations occur on two distinct scales and represent the preserved expression of both small scale autocyclic behaviour of competing coeval depositional systems and larger scale allocyclic changes that record system response to longer term interdependent variations in climatic and eustatic controlling mechanisms the architectural relationships and system interactions observed in the lower cutler beds demonstrate that the succession was generated by several cyclical changes in both climate and relative sea level and that these two external controls probably underwent cyclical change in harmony with each other in the paradox basin during late pennsylvanian and permian times this observation supports the hypothesis that both climate and eustasy were interdependent at this time and were probably responding to a glacio eustatic driving mechanism

eolian origin of upper paleozoic sandstones southeastern utah abstract throughout its outcrop in southeastern utah the permian cedar mesa sandstone contains large scale crossbedding and is devoid of marine fossils except for sand size skeletal fragments although this rock unit has been interpreted by several recent workers as shallow marine stratification identical to that documented in modern eolian dunes is ubiquitous in the cedar mesa thin inversegraded laminations within crossbeds represent the unique product of climbing wind ripples this type of stratification is the best evidence for an eolian origin of the cedar mesa such an interpretation is strongly supported by other evidence vertebrate trackways and simple small cylindrical burrows constitute a distinctively nonmarine ichnofauna rhizoliths root casts are abundant at many stratig aphic levels in the underlying rico and hermosa formations sandstones with physical and biogenic sedimentary structures identical to those in the cedar mesa are interbedded with crossbedded limestones with abundant megafossils and marine traces contacts between sandstones and limestones are sharp gradational relationships would be expected if both sandstones and limestones accumulated subaqueously siliciclastic pebbles are present in some of these carbonate rocks suggesting that the well sorted nature of the sandstones cannot be attributed to the unavailability of coarse clasts palcocurrent data from the sandstones and limestones show significantly different vector means and variance southward pinchout of marine carbonates indicates that winds were onshore winnowing of silicicla tics from coarser carbonate detritus created a strong dichotomy in bulk mineralogy between marine and eolian sediments reinterpretation of the sandstones necessitates reappraisal of ideas concerning the mineralogical maturity of these sediments the relative importance of eolian and shallow marine transport processes to the destruction of labile siliciclastics is unknown

late jurassic fluvial eolian deposits from the tianchihe formation ningwu jingle basin shanxi province china abstract eolian systems were widespread in china in the cretaceous however the reports of pre cretaceous eolian and its related systems are scarce which prohibits studying the construction accumulation and preservation of eolian systems as well as its allogenic and autogenic controlling factors in this paper we report on fluvial eolian successions from the late jurassic tianchihe formation in the ningwu jingle basin these successions represent the oldest reported inland fluvial eolian systems in china fourteen lithofacies types are recognized in the tianchihe formation and have been grouped into six facies associations including meandering fluvial channel levee and overbank in the lower part and eolian sandsheet eolian dune ephemeral fluvial channel and floodplain in the upper part the fluvial system comprises a series of wetting upward cycles which indicate humid climate culminating in high precipitation and shallow water table level eolian dune deposits composed of grainflow grainfall wind ripple strata and pin stripe laminations currently implies that all deposits types are internally bounded by reactivation surface and superimposition surface suggesting compound dunes or draas eolian sandsheet deposits consist dominantly of subcritical climbing translatent strata and pin stripe lamination the association of eolian dune and eolian sandsheet is development of a dry eolian system twelve drying upward cycles mainly composed of eolian sandsheet eolian dune successions and four wetting upward cycles consisting of eolian sandsheet dune ephemeral fluvial channel floodplain successions occur in the eolian system these repeated cycles likely reflect an evolving erg system directly controlled by sediment supply sediment availability and relative water table the vertical transition from fluvial to eolian systems indicate a local climatic oscillation from relatively humid to arid conditions which may be related with the uplift of the east china plateau in the late jurassic

palaeonvironmental and palaeoecological significance of flamingo like footprints in shallow lacustrine rocks an example from the oligocene miocene vinchina formation argentina abstract this article describes the lacustrine trace fossil assemblage of the late oligocene early miocene vinchina formation of northwest argentina the thick 5000 m continental succession of the formation is essentially fluvial with thin aeolian and lacustrine intervals the trace fossil assemblage from the lacustrine facies is dominated by bird footprints notably flamingo like palmate bird footprints and also contains invertebrate traces the assemblage is of contrasting composition with those of the ubiquitous fluvial facies of the vinchina formation we identify the possible trace maker of the web footed bird footprints and infer the palaeoenvironmental and palaeoecological meaning of the lacustrine trace fossil assemblage of the vinchina formation the lacustrine succession is mainly composed of wave rippled fine grained sandstones and siltstones and wave rippled heterolithic facies with subordinate laminated mudstone and medium grained sandstone with parallel lamination or cross bedding metre scale shallowing upward cycles are typical and desiccation cracks were observed in a single bedding plane the analysed interval was deposited in a wave dominated littoral zone of a shallow permanent lake basin ichnofossils were found mostly in three trampled horizons of the upper part of the analysed succession the trace fossil assemblage is dominated by phoenicopterichnum isp flamingo like footprints slender bird tracks without web traces and triangular and fusiform hypichnial ridges interpreted as bird undertracks the remaining trace fossils are lockeia siliquaria bivalve resting trace rusophycus isp shallow arthropod burrow taenidium barretti endostratal meniscate burrow and small hypichnial double knobs possible beak probing marks neoichnological observations on modern chilean flamingo footprints phoenicopterus chilensis suggest that phoenicopterichnum isp is morphologically akin to modern flamingo footprints although its average size is slightly smaller the likely producers of the fossil footprints are members of the palaelodidae and phoenicopteridae which are recorded in south america since the late oligocene phoenicopterichnum isp appears in cuasi parallel trackways with short pace length and forming a low angle with ripple crests by comparison with observations of modern flamingo behaviour during this study and of shorebird studies from the literature these tracks and trackways likely reflect flock feeding behaviour probably filter feeding in a subaqueous belt parallel to the waterline invertebrate ichnofossils that appear on the same slabs from trampled horizons are mainly triangular and fusiform hypichnial ridges while phoenicopterichnum isp and sparse small hypichnial double knobs also occur in consequence it is possible that these birds were foraging on small invertebrates represented by lockeia siliquaria rusophycus isp and probably taenidium barretti in the coast of the vinchina lake the only fossil evidence for these invertebrates is the impression of articulated valves probably belonging to a small mollusc potential producer of lockeia trace fossil assemblages dominated by flamingo like footprints including ichnogenera phoenicopterichnum culcitapeda and similar unnamed tracks are indicative of alkaline and or saline waters as suggested by the specialised filter feeding mechanism of late oligocene to modern phoenicopteriformes these particular assemblages are distinguished as a subset within the shorebird ichnofacies with a definite palaeoenvironmental and palaeoecological meaning the phoenicopterichnum ichnosubfacies

pennsylvanian to jurassic eolian transportation systems in the western united states peterson f 1988 pennsylvanian to jurassic eolian transportation systems in the western united states in g kocurek editor late paleozoic and mesozoic eolian deposits of the western interior of the united states sediment geol 56 207 260 the direction of sediment transport in eolian sandstones of permsylvanian to jurassic age was interpreted from crossbedding resultants vector means obtained from studies of eolian rocks in the western u s supplemented by data from the few eolian units of eastern north america these were compiled from the published or unpublished theses hterature from unpublished fidd data contributed by colleagues or from measurements made for this study in addition new paleogeographic maps were compiled to evaluate the influence of geographic features on the atmospheric circulation patterns that are inferred from the crossbedding studies regionally the crossbedding indicates northeasterly northerly or northwesterly winds present coordinates from pennsylvanian through most of middle jurassic time a rather abrupt change in wind directions occurred in late middle jurassic time late part of the cauovian age when westerly wind patterns developed by the late jurassic the winds shifted to southwesterly calculations of the consistency factor vector mean strength made from region wide analyses of the resultants indicate fairly unidirectional winds from the permsylvanian through the early jurassic middle jurassic circulation was more varied judging from crossbedding studies in the lower part of the entrada sandstone crossbedding in upper jurassic eolian rocks of wyoming and south dakota yielded a random pattern but upper jurassic rocks farther south on the colorado plateau and adjoining areas show a return to a fairly unidirectional pattern comparing the resultants with their reconstructed paleogeographic setting shows surprisingly little influence of major geographic features on overall circulation patterns however the greatest amount of local variation occurred at or near highly indented shorelines where the temperature contrast between land and water produces local wind currents that may vary appreciably from regional circulation patterns although they do not cause noticeable horizontal deflections in wind patterns small and low topographic highs appear to be able to promote the development of a dune field if a source of sand is available and if streams do not enter the growing dune field

dynamics of slow moving landslides from permanent scatterer analysis high resolution interferometric synthetic aperture radar insar permanent scatterer data allow us to resolve the rates and variations in the rates of slow moving landslides satellite to ground distances range changes on landslides increase at rates of 5 to 7 millimeters per year indicating average downslope sliding velocities from 27 to 38 millimeters per year time series analysis shows that displacement occurs mainly during the high precipitation season during the 1997 1998 el nino event rates of range change increased to as much as 11 millimeters per year the observed nonlinear relationship of creep and precipitation rates suggests that increased pore fluid pressures within the shallow subsurface may initiate and accelerate these features changes in the slope of a hill resulting from increases in the pore pressure and lithostatic stress gradients may then lead to landslides

tracer techniques in aeolian research approaches applications and challenges abstract aeolian processes the entrainment transport and deposition of sediments by wind impacts climate biogeochemical cycles food security environmental quality and human health considering the multitude of interactions between aeolian processes and all the major components of the earth system there is a growing interest in the scientific community to quantify the wind related sediment movement process and redistribution rates at different spatial and temporal scales however this quantification is rather challenging due to the complexities of physical mechanisms involved in aeolian processes and the inherent fundamental differences from the rather well studied processes controlling fluvial erosion traditional techniques such as erosion plots and surveying methods for monitoring wind erosion are capable of quantifying sediment movement on small scales but they have a number of limitations in terms of the representativeness of the data obtained spatial and temporal resolution and the patterns over extended areas and the costs involved the demand for alternative methods of soil loss and sediment redistribution assessment in order to complement and enhance the existing methods has directed attention to use tracing approaches for monitoring rates and spatial patterns of sediment redistribution at various scales a comprehensive synthesis of available information from different scientific disciplines on aeolian tracer techniques their applications and limitations are important in understanding the role of aeolian processes and their interactions with the earths systems in changing climate and management scenarios the objective of this paper is to provide a scientific review of the current tracer approaches in aeolian studies including fallout radionuclides rare earth elements sediment finger printing and soil magnetism as well as giving an introduction of the potential tracers that are in development

rhizoliths in ancient eolianites abstract rhizoliths are abundant within permo pennsylvanian eolian rocks of southeastern utah they are also present at the tops of several eolian sand bodies within the pennsylvanian fountain formation of southeastern wyoming and at a single stratigraphic level within the jurassic navajo sandstone of southeastern utah ranging in diameter from less than 1 mm to 15 cm these cylindrical structures are composed of siliciclastic free micrite and calcite spar cylinders ramify throughout the uppermost 2 3 m of thin flat topped sand bodies large cylinders are compound rhizoliths and display alveolar fabric a feature resulting from rootlet calcification that is characteristic of modern and ancient calcretes development of rhizoliths required flat geomorphically stable substrates for plant growth highly permeable surficial sediments and sources of calcium ions the restriction of rhizoliths to planar deflation surfaces suggests that plants were unable to colonize or stabilize eolian bedforms paleozoic rhizoliths appear to be restricted to coastal areas with onshore winds associated evaporites suggest an arid to semi arid paleoclimate rhizoliths formed when carbonate allochems derived from an upwind epeiric sea were dissolved and calcite reprecipitated around plant roots quaternary rhizoliths are best developed in similar sedimentologic and geographic settings the abundance of rhizoliths and carbonate allochems in quaternary and late paleozoic low latitude coastal dunes suggests that they are genetically related to glacio eustatic sea level fluctuations

helical burrow casts of therapsid origin from the beaufort group permian of south africa abstract large helical burrow casts of vertebrate origin have been discovered at several localities in the lowermost strata of the teekloof formation of the beaufort group permian in the southwestern karoo basin south africa they are not only the oldest but also the first vertebrate burrows of helical geometry to be found in rocks of pre mammalian age the burrow casts are vertically disposed spiralling tubes filled with fine grained sandstone or siltstone often with a calcareous cement tube diameters gradually increase from 60 mm in the upper entrance decline through two non contacting dextral coils to about 160 mm at the base of the spiral whereupon the tube straightens and widens into a horizontal terminal chamber burrow depths range from 0 5 0 75 m and the ramp angle ranges from 10 to 32 although within any single spiral it is constant articulated skeletons of the small dicynodont diictodon have been found within the terminal chambers and spirals of three sand filled burrows linear ridges preserved on the outer walls and floor of some of the terminal chambers resemble scratch marks possibly made by the claws and beak of diictodon during burrow excavation the sedimentary sequences at two separate localities are interpreted as having been deposited by episodic sheet floods and distributary splay fans in the proximal floodbasin areas flanking an aggrading meanderbelt rise comparison is drawn between helical burrow casts in the lower beaufort and other recorded occurrences in particular daimonelix a beaver burrow from the miocene of nebraska fundamental similarities far outweigh differences to the extent that the beaufort helical burrows may be grouped with the daimonelices it is concluded that the excavation of large helical burrows an activity usually attributed to rodents was pre empted by mammal like reptiles some 50 million years before the first anatomical mammals evolved

pink fairy armadillo meniscate burrows and ichnofabrics from miocene and holocene interdune deposits of argentina palaeoenvironmental and palaeoecological significance abstract the possible producer and environmental setting of large meniscate burrows nagtuichnus meuleni igen and isp nov occurring in late miocene and holocene aeolian deposits from argentina are discussed these are unbranched burrows with an uniform meniscate filling that range in width from 46 to 78 mm n meuleni distinguishing features are a filling composed of a discontinuous outer massive layer between a central meniscate core and the excavation boundary sets of parallel ridges in the external wall and a particular outline plus the presence of paired pits in the concave surface of menisci or hollows in the convex surface the late miocene lower member of the rio negro formation at la loberia rio negro province is interpreted as aeolian dune damp interdune and dry interdune deposits the holocene sediments from gran salitral southwestern la pampa province represent aeolian dune wet interdune and dry interdune deposits n meuleni occurs only in damp and dry interdune deposits the composite ichnofabric produced by n meuleni in the holocene of the gran salitral is composed of two suites of trace fossils a former skolithos suite includes skolithos linearis taenidium barretti polykladichnus aragonensis and root traces developed in lacustrine calcareous mudstone deposits wet interdune this suite is overprinted by n meuleni with subordinate participation of s linearis and root traces composing the nagtuichnus suite the later suite is developed in brown silt and sand of dry interdune areas the nagtuichnus ichnofabric is considered indicative of damp to dry interdune facies of late miocene to holocene age the burrow systems of the likely producers of the holocene n meuleni structures were studied in the field and in the laboratory the candidates were selected from the extant local fauna of the gran salitral including southern cavies microcavia australis rodentia tuco tucos ctenomys azarae rodentia and pink fairy armadillos or pichiciegos chlamyphorus truncatus xenarthra the most likely producer of n meuleni are pichiciegos because they have fully subterranean habits and insectivorous diet involving the production of long unbranched horizontal burrows excavated in sand which are mostly backfilled in contrast to this tuco tucos and southern cavies which are herbivores that forage aboveground use their more permanent burrows for dwelling and reproduction as observed in a live captive kept c truncatus the meniscate structure of the fill can be explained by the animal packing the excavated sand with its rump plate this mechanism also results in a massive layer of sediment in the burrow fill other significant bioglyphs that are a sort of fingerprint of pichiciegos are the outline of menisci in cross section mimicking their rump plate and pairs of rounded pits in the concave surface of menisci probably tail traces

ant nest ichnofossils in honeycomb calcretes neogene ogallala formation high plains region of western kansas u s a abstract two new ant nest trace fossils are described from calcic sandy paleosols of the neogene ogallala formation in western kansas the ichnofossils are preserved within and below calcrete beds weathering in positive relief as carbonate filled casts or as cavities in negative relief daimoniobarax ichnogenus nov is established for burrow systems composed of vertically tiered horizontally oriented pancake shaped chambers connected by predominantly vertical and cylindrical shafts 0 8 cm in diameter ichnospecies of daimoniobarax are differentiated based on differences in the plan view outline of chambers shaft orientation and junctions between chambers and shafts daimoniobarax nephroides ichnospecies nov is composed of an 24 76 cm long vertical sequence of distinctly lobed chambers 2 20 cm wide and 1 cm high arranged along sinuous to helical shafts chamber shape in plan view ranges from small teardrops to larger kidney and u shaped forms shafts intersect at chamber edges such that chambers appear to bud from the central shafts daimoniobarax nephroides is most similar to the nests of extant seed harvester ants of the new world genus pogonomyrmex such ants are specialized granivores and prefer sandy soils in arid to semi arid grassland and desert regions daimoniobarax tschinkeli ichnospecies nov is 30 80 cm in vertical extent chambers 2 30 cm wide and 1 cm high are circular to elongate or pseudopodial in plan view vertical shafts are straight to slightly sinuous and intersect most often toward the center of the chambers the generalized architecture of d tschinkeli is similar to that of the nests or nest portions of several extant ant genera though it does not closely resemble any known modern nest ant ichnofossils provide valuable information on hidden biodiversity paleohydrologic regimes paleopedogenic processes and paleoclimate during the time of nest occupation depth related changes in chamber size and vertical spacing may also help interpret paleosurfaces and paleodepths and serve as geopetal features

paleohydrological significance of trace fossil distribution in oligocene fluvial fan to lacustrine systems of the ebro basin spain the ichnological study of fluvial fan and lacustrine oligocene deposits in the ne ebro basin has allowed the recognition of three ichnoassemblages having a strong correlation with depositional facies associations lacustrine deposits lack bioturbation due to the hydrologically closed character of the lake that caused hypersalinity and made it inhospitable for benthic life terminal lobe deposits of the fluvial fan which were sedimented in low wetland areas around the lake bear a moderately diverse ichnoassemblage dominated by horizontal taenidium barretti cochlichnus anguineus and bird footprints gruipeda isp this assemblage can be assigned to the shorebird ichnofacies a subset of the scoyenia ichnofacies that characterizes the subaerial part of low energy shore areas crevasse splay deposits in medial fluvial fan areas present a different assemblage also belonging to the scoyenia ichnofacies it includes most of the trace fossils found in the terminal lobes except for the bird tracks plus very abundant vertical burrows taenidium barretti and unnamed ornamented burrows the presence of deep tier traces of terrestrial invertebrates is consistent with the more proximal fan setting having greater relief and consequently a lower mean groundwater position than lowland areas fluvial channels only bear irregularly clustered tunnel structures of unknown affinity formed after abandonment of the channel thus trace fossil assemblages are mostly controlled by the position and fluctuations of water tables which are the cause for their composite nature

aeolian stratification and facies association in desert sediments arran basin permian scotland abstract permian aeolian sediments on the island of arran are divisible into dune including draa and interdune deposits both types display a distinctive and unusually wide variation in grain size the dominant features of the dune deposits are grainfall lamination sandflow lamination and inverse graded lamination associated with ripple form lamination and normal graded lamination the flat lying aeolian interdune deposits are characterised by granule and sand ripples horizontal lamination in coarse sand and granules plane bed lamination and inverse graded lamination associated structures include ripple form lamination and deflation lags three types of trace fossil associated with completely bioturbated horizons occur in some low angle dune and interdune deposits the aeolian facies interfinger with alluvial fan deposits giving rise to three recognizable facies belts marginal aeolian deposits are associated with fluvial conglomerates and are dominated by interdune deposits and occasionally very thin barchan deposits set height 3 37 cm intermediate aeolian deposits are characterized by interbedded crescentic dune small draa dune set height 5 cm 4 5 m and interdune deposits and rare fluvial and lake sediments basinal aeolian deposits are dominated by draa deposits dune set height 0 2 28 m associated with rare interdune sediments transverse dunes and draas were moved by north eastern palaeowinds towards the foot of the alluvial fans the aeolian sediments were deposited in a fault bounded desert basin

vertebrate tracks in pleistocene eolian sand sheet deposits of alaska abstract deformation structures interpreted as vertebrate hoof and foot tracks occur within upper pleistocene eolian sand sheet deposits in the stabilized kantishna sand sea of central alaska and in the nushagak lowland of southwestern alaska exposures of tracks are generally limited to cross sections which reveal concave up deformation structures in which displacement of preexisting strata diminishes downward deposits in both areas contain tracks that are 6 to 16 cm in diameter and are divided by a central ridge reflecting formation by artiodactyl even toed ungulates larger 21 34 cm tracks without a central ridge observed in the nushagak lowland were formed by proboscideans probably woolly mammoth large vertebrate tracks occur within irregularly stratified sand and silty sand that accumulated upon partially vegetated sand sheets and within thin even wind ripple laminae of unvegetated sand sheets the presence of tracks at multiple stratigraphic levels and preservation of roots and rhizocretions within the eolian deposits suggest that vegetated sand sheets may have formed a locally important grazing habitat for large herbivores during at least part of the last glaciation recognition that vertebrate tracks are preserved in eolian sand sheet deposits and in deposits of other environments as well opens a new source of stratigraphic and paleoecological data to aid reconstruction of the vanished ecosystems of beringia

large area landslide detection and monitoring with alos palsar imagery data over northern california and southern oregon usa abstract multi temporal alos palsar images are used to automatically investigate landslide activity over an area of 200 km by 350 km in northern california and southern oregon interferometric synthetic aperture radar insar deformation images insar coherence maps sar backscattering intensity images and a dem gradient map are combined to detect active landslides by setting individual thresholds more than 50 active landslides covering a total of about 40 km 2 area are detected then the short baseline subsets sbas insar method is applied to retrieve time series deformation patterns of individual detected landslides down slope landslide motions observed from adjacent satellite tracks with slightly different radar look angles are used to verify insar results and measurement accuracy comparison of the landslide motion with the precipitation record suggests that the landslide deformation correlates with the rainfall rate with a lag time of around 1 2 months between the precipitation peak and the maximum landslide displacement the results will provide new insights into landslide mechanisms in the pacific northwest and facilitate development of early warning systems for landslides under abnormal rainfall conditions additionally this method will allow identification of active landslides in broad areas of the pacific northwest in an efficient and systematic manner including remote and heavily vegetated areas difficult to inventory by traditional methods

monitoring of post failure landslide deformation by the ps insar technique at lubietova in central slovakia interferometric synthetic aperture radar data from ers and envisat sensors were utilized in the analysis of the post failure deformations in the area of lubietova town in central slovakia the catastrophic landslide of 1977 together with surrounding landslides in the lubietova area were analysed with the help of persistent scatterers ps technique in order to evaluate recent and past deformations of the unstable slopes although long term precise geodetic monitoring of the 1977 landslide revealed differential deformations inside the sliding mass due to the lack of the ps located inside the landside caused by temporal decorrelation unfortunately these records could not be directly compared the adjacent landslides with sufficient number of ps were analysed by transformation of the line of sight displacements recorded by the sensors to the slope vector direction this procedure allowed identification of the precise boundaries of the actively moving landslide parts and the updating of the landslide inventory for the lubietova area

burrows dug by large vertebrates into rain moistened middle jurassic sand dunes abstract in south central utah eolian cross strata of the escalante member of the entrada sandstone contain inclined cylindrical burrows up to 63 cm in diameter and 305 cm long of the 14 large tunnels located during this study 12 descend from second and third order bounding surfaces that formed on the lee slopes of large dune ridges well above the water table the tunnels are inclined 15 22 one tunnel ends in an expanded chamber eolian cross strata fill proximal portions of four of the tunnels and indicate that after abandonment sand drifts migrated as much as a meter into the open shafts structureless sand and breccia blocks that were generated by roof collapse fill other tunnels animals dug the tunnels in rain moistened cohesive sand the burrows may have served as temporary shelters from severe diurnal conditions in the shadeless subtropical entrada dune field

detecting slope deformation using two pass differential interferometry implications for landslide studies on earth and other planetary bodies landslide features have been identified on earth and the moon mars venus as well on the jovian moons by focusing on a terrestrial landslide complex we test the operational parameters of radarsat 1 and the use of two pass differential interferometry to detect change to map its extent and to measure the amount of movement over a given time period radarsat 1 was chosen because of its variable imaging modes and geometry for investigations of landslide motions using remote sensing techniques repeat pass data are required synthetic aperture radar sar interferometry insar can ideally monitor movements across the whole surface of a landslide to a millimeteric precision yielding a coverage significantly better than that obtained by ground instrumentation obtaining optimal data for insar analysis requires controlled orbital characteristics and imaging geometries an understanding of the landslide characteristics and behavior a cooperative surface and mitigation of the factors that can affect phase using two pass differential interferometry a slope deformation map has been generated from radarsat 1 data for part of the black ven landslide 2 52 w 50 40 n on the south coast of england four months separate the insar pair during which time 0 03 m of subsidence was measured from this a movement rate of 0 09 m yr can be calculated this agrees well with ground observations and an in situ record of movement thus demonstrating that the technique can be used to investigate landslides with further refinement it can provide more direct measurements of landslide deformation on earth and other planetary bodies than are currently available

tracks and trackways of myotragus balearicus bate artiodactyla caprinae in pleistocene aeolianites from mallorca balearic islands western mediterranean tracks and trackways of the ruminant goat myotragus balearicus bate 1909 are abundant in the late pleistocene aeolianites of the south coast of mallorca spain the carbonate aeolianites form impressive dunes and related sand ramps that were initiated as echo dunes in front of a 20 40 m high paleocliff of miocene reefal limestone where the dunes built up to the cliff top they covered it as an aeolian ramp the dunes and sand ramps were active during the dry summer months but were passive during the wet winter period the small goat like animals were abundant on the island and for unknown reasons crossed the aeolian accumulations in large numbers this study deals with the tracks formed in the dune deposits all preserved trackways indicate impression into moist sand special features of the tracks include the structure produced by the withdrawal of the foot here called the axis and a disturbance zone of plastic deformation around this on dune crests the disturbance zone surrounds the axis more or less symmetrically however in addition a pressure pad of dislocated slightly rotated sediment bound by curved microfaults is commonly produced posterior to the axis by propulsive pressure of the foot on steep stoss and lee slopes the pressure pad becomes oriented in a down slope position as a result of gravitational slip of the walking animal combination of disturbance of the sediment in this way by manus followed by overprinting of similar disturbance by pes produces highly complicated track structure this structure may be characteristic of artiodactylous mammals in soft sand particularly aeolian deposits the structure is designated as bifidipes aeolis isp nov