reach scale sediment transfers an evaluation of two morphological budgeting approaches this paper compares two approaches used to derive measures of annual sediment transfers within a 1 km long piedmont reach of the gravel bed river coquet in northumberland northern england the techniques utilize i channel planform and cross section surveys based on a theodolite electronic distance measurement edm survey of 21 monumented channel cross sections and channel and gravel bar margins and ii theodolite edm survey generating a series of x y z coordinates from which digital elevation models dems of the reach were constructed calculating the difference between dem surfaces provided a measure of volumetric change between surveys carried out during the spring of 1999 and 2000 the use of kriging in dem generation and differencing permits computation of estimate variances and confidence intervals for sediment transfer error analysis validating the dems using surveyed cross sections indicated a mean error between surveyed and dem generated cross sections of around twice the value of the d50 of the surface sediment in the reach comparison of sediment volumes derived from the two approaches suggests that compared with the dem method monumented cross sections underestimate the magnitude of volumetric changes that occur within the reach the cross section approach relies on a simplistic integration of the volumes whereas dem differencing provides an estimate at a resolution under the control of the analyst furthermore the cross section approach does not permit a reliable estimate of the uncertainty of the volumes calculated in addition the dem methodology based on the morphological unit scale provides an explicit identification of spatial patterns of erosion and deposition a feature that cross section based approaches may fail to include copyright 2003 john wiley sons ltd

groundwater electrical conductivity and soil radon gas monitoring for earthquake precursory studies in koyna india abstract hourly monitoring of electrical conductivity ec of groundwater along with groundwater levels in the 210 m deep boreholes specially drilled for pore pressure earthquake studies and soil rn gas at 60 cm below ground level in real time in the koyna warna region characterized by basaltic rocks 1500 m thick and dotted with several sets of fault systems western india provided strong precursory signatures in response to two earthquakes m 4 7 on 14 11 09 and m 5 1 on 12 12 09 that occurred in the study region the ec measured in govare well water showed precursory perturbations about 40 h prior to the m 5 1 earthquake and continued further for about 20 h after the earthquake in response to the m 4 7 earthquake there were ec perturbations 8 days after the earthquake in another well koyna which is located 4 km north of govare well no precursory signatures were found for the m 4 7 earthquake while for m 5 1 earthquake post seismic precursors were found 18 days after the earthquake increased porosity and reduced pressure head accompanied by mixing of a freshwater component from the top zone due to earthquakes are the suggested mechanisms responsible for the observed anomalies in ec another parameter soil rn gas showed relatively proportional strength signals corresponding to these two earthquakes in both the cases the pre seismic increase in rn concentration started about 20 days in advance the co seismic drop in rn levels was less by 30 from its peak value for the m 4 7 earthquake and 50 for the m 5 1 earthquake the rn anomalies are attributed to the opening and closing of micro fractures before and during the earthquake on line monitoring of these two parameters may be useful to check the entire chemistry change due to earthquake which may help to forecast impending earthquakes

on the origin and post depositional history of widespread massive ash deposits the case of intermediate brown tuffs ibt of lipari aeolian islands italy abstract we analysed a widespread massive ash unit outcropping on the island of lipari which belongs to the intermediate brown tuffs ibt succession of the aeolian islands italy the use of a multidisciplinary approach that integrates textural petrological and pedological methods allows us to discriminate between syn eruptive and post depositional features the deposits are dominated by uncrystallised blocky glass fragments of homogeneous shoshonitic composition confirming a provenance from hydromagmatic eruptions on the island of vulcano many glass fragments are surrounded by a coating separated by a thin void of syn eruptive origin due to alteration by aggressive acid gases in the eruptive cloud the lack of this coating in the northern part of lipari can be explained as a progressive dispersion of the gases far from the vent and or to post depositional processes the degree of soil development significantly increases from south soil profiles p1 and p2 at valle muria to north p3 and p4 at madoro and chiesa vecchia sites respectively as a response to a decrease in slope steepness which has brought about a progressive deepening of the pedogenetic front on gentler landforms and conversely its rejuvenation on steep slopes the relatively poor to moderate degree of pedogenic evolution of the studied ibt unit is consistent with its emplacement during part of the last glacial period

developments in monitoring and modelling small scale river bed topography recent research in fluvial geomorphology has emphasized the spatially distributed feedbacks amongst river channel topography flow hydraulics and sediment transport although understanding of the behaviour of dynamic river channels has been increased markedly through detailed within channel process studies less attention has been given to the accurate monitoring and terrain modelling of river channel form using three dimensional measurements however such information is useful in two distinct senses firstly it is one of the necessary boundary conditions for a physically based deterministic modelling approach in which three dimensional topography and river discharge drive within channel flow hydraulics and ultimately spatial patterns of erosion and deposition and therefore channel change secondly research has shown that an alternative means of estimating the medium term bedload transport rate can be based upon monitoring spatial patterns of erosion and deposition within the river channel this paper presents a detailed assessment of the distributed monitoring and terrain modelling of river bed topography using a technique that combines rigorous analytical photogrammetry with rapid ground survey the availability of increasingly sophisticated terrain modelling packages developed for civil engineering application allows the representation of topographic information as a landform surface intercomparison of landform surfaces allows visualization and quantification of spatial patterns of erosion and deposition a detailed assessment is undertaken of the quality of the morphological information acquired this allow some general comments to be made concerning the use of more traditional methods to monitor and represent small scale river channel morphology

radon earthquake precursor studies in iceland discrete samples of geothermal water have been collected from a network of nine stations for analysis of radon 222 rn content the sampling network consisted of wells that range in wellhead temperature from 48 c to 100 c and the depths range from 38 m to 1338 m the sampling frequency at most stations was about once per week and twice per week at the station fludir the wells are either artesian or pumped more or less continuously the network covered two regions of transform faulting in iceland with seven stations in the southern iceland seismic zone sisz and two stations in northern iceland in the tjornes fracture zone tfz during 1978 and 1979 several anomalous changes in radon content were observed to precede some of the local earthquakes criteria based on tectonic regimes a magnitude distance relationship and time clustering were applied to select a set of 23 earthquakes that could be expected to be preceded by a radon anomaly the magnitude of these earthquakes ranged between 1 0 and 4 3 each of the 23 earthquakes was within the distance range of one or more stations such that altogether 57 potential observations of possible anomalies were available the method of analysis applied to the radon and earthquake data consisted of identifying radon anomalies in retrospect and resulted in nine precursory anomalies 48 cases of failure to observe an anomaly and seven false alarms the probability of observing radon anomalies before earthquakes with magnitudes between 2 0 and 4 3 the largest event observed was found to be approximately 65 based on a weekly sampling rate in the sisz five out of eight earthquakes m 2 were preceded by an anomaly in two cases anomalies were observed at two different stations prior to the same earthquake the anomalies appeared to occur farther away for larger earthquake magnitude an aquiclude that divides the sisz did not seem to affect the occurrence of radon anomalies but the amplitude of anomalies on the east side were larger than the ones on the west side the duration times of the anomalies ranged from 17 to 37 days the large number of failures to observe an anomaly indicated that the occurrence of an anomaly was more strongly dependent on local conditions and earthquake parameters than distance between epicenter and radon station some stations also appeared to be less sensitive than others and three stations never showed an anomaly during periods of bursts in local seismicity some stations reflected distinctively larger background fluctuations which hampered the correlation of the seismicity with the radon data most of the false alarms were related to disturbances caused by changes in well operation in the sisz the high rate of failure to observe an anomaly and the occurrence of false alarms was partly compensated for by operating a dense network of sampling stations wells that are utilized at moderate flow rates are less likely to show false alarms than wells utilized at high flow rates wells situated close to rock formations rich in radioactive minerals may be more likely to show anomalies than others

towards a protocol for laser scanning in fluvial geomorphology advances in spatial analytical software allow digital elevation models dems to be produced which accurately represent landform surface variability and offer an important opportunity to measure and monitor morphological change and sediment transfer across a variety of spatial scales many of the techniques presently employed aerial lidar edm theodolites gps photogrammetry suffer coverage or resolution limitations resulting in a trade off between spatial coverage and morphologic detail captured this issue is particularly important when rates of spatial and temporal change are considered for fluvial systems this paper describes the field and processing techniques required for oblique laser scanning to acquire 0 01 m resolution digital elevation data of an upland reach of the river wharfe in the uk the study site is variable with rapidly changing morphology diverse vegetation and the presence of water and these are evaluated with respect to laser data accuracy scan location frequency and distance are discussed with reference to survey accuracy and efficiency and a field protocol is proposed scan data cloud merging was achieved with a high degree of precision sub centimetre and positional data are shown to be very accurate for exposed surfaces vegetation and water decrease the accuracy as the laser pulse is often prevented from reaching the ground surface or is not returned copyright 2006 john wiley sons ltd

earthquake prediction in northeast india a review a multidimensional geophysical approach is made to study earthquake precursors in northeast india resistivity gravity and seismological precursor anomalies for the two recent damaging earthquakes one on december 30 1984 magnitude 5 8 and the other on august 6 1988 magnitude 7 5 are very encouraging to intensify these studies in the region improved methods of magnetic and geohydrological precursor studies are suggested

hydrogeological and geochemical control of the variations of 222rn concentrations in a hard rock aquifer insights into the possible role of fracture matrix exchanges to investigate the possible variations of rn concentration in crystalline rocks as a function of flow conditions a field study was carried out of a fractured aquifer in granite the method is based on the in situ measurement of rn in groundwater aquifer tests for the determination of hydraulic characteristics of the aquifer and laboratory measurement of rn exhalation rate from rocks a simple crack model that simulates the rn concentration in waters circulating in a fracture intersecting a borehole was also tested the rn concentrations in groundwaters from boreholes of the study site ranged from 192 to 1597 bq l 1 the rn exhalation rates of selected samples of granite and micaschist were determined from laboratory experiments the results yielded fluxes varying from 0 5 to 1 3 mbq m 2 s 1 in granite and from 0 5 to 0 9 mbq m 2 s 1 in micaschists pumping tests were performed in the studied boreholes to estimate the transmissivity and calculate the equivalent hydraulic aperture of the fractures transmissivities ranged from 10 5 to 10 3 m2 s 1 using the cubic law hydraulic equivalent fracture apertures were calculated to be in the range of 0 5 2 3 mm to gain a better insight into the spatial variability of rn contents in groundwater theoretical rn concentrations were calculated from an available simple crack model using results from field and laboratory experiments this model gave satisfactory results for boreholes characterized by low flow conditions in which case the calculated rn contents were in the range of rn concentrations set by the analytical uncertainty of concentrations measured in water however for boreholes characterized by high flow conditions the model underestimated the rn concentration in groundwater the higher the flow in the fracture the larger the difference between calculated and measured rn concentrations in water these observations led to performing pumping tests to obtain a better understanding of the hydrogeological control of rn content in water the results clearly show an increase of rn content in groundwater after the pumping test which could be explained by the input of rn rich waters from the host matrix

radon measurements for earthquake prediction along the north anatolian fault zone a progress report abstract radon 222rn concentration has been continuously measured since 1983 in groundwater at a spring and in subsurface soil gas at five sites along a 200 km segment of the north anatolian fault zone near bolu turkey the groundwater radon concentration showed a significant increase before the biga earthquake of magnitude 5 7 on 5 july 1983 at an epicentral distance of 350 km and a long term increase between march 1983 and april 1985 the soil gas radon concentration showed large changes in 1985 apparently not meteorologically induced the soil gas and groundwater data at bolu did not show any obvious correlation

impulsive radon emanation on a creeping segment of the san andreas fault california radon emanation was continuously monitored for several months at two locations along a creeping segment of the san andreas fault in central california the recorded emanations showed several impulsive increases that lasted as much as five hours with amplitudes considerably larger than meteorologically induced diurnal variations some of the radon increases were accompanied or followed by earthquakes or fault creep events they were possibly the result of some sudden outbursts of relatively radon rich ground gas sometimes triggered by crustal deformation or vibration

earthquake prediction a new physical basis summary subcritical crack growth in the laboratory occurs slowly but progressively in solids subjected to low stresses at low strain rates the cracks tend to grow parallel to the maximum compressive stress so that when this stress is aligned over a large enough region the cracks will also be aligned and possess effective seismic anisotropy it is suggested that such subcritical crack growth produces extensive dilatancy anisotropy eda throughout earthquake preparation zones this process is a possible driving mechanism for earthquake precursors observed at substantial distances from impending focal zones and provides in the shear wave splitting which has been observed in several seismic regions a possible technique for monitoring the build up of stress before earthquakes

the development of an automated correction procedure for digital photogrammetry for the study of wide shallow gravel bed rivers this paper develops an automated correction procedure for dealing with point errors associated with through water photogrammetry for application in the study of clear water shallow gravel bed rivers the procedure involves combining digital photogrammetry and image analysis techniques to i correct for the effects of refraction at an air water interface and ii eliminate and reinterpolate points where the bed has not been seen the correction procedure was applied to raw digital elevation models dems generated using digital photogrammetry from 1 3000 scale aerial photography of a small reach of the north ashburton river new zealand the accuracy of corrected and uncorrected dems is evaluated using an independent data set a measure of geomorphological usefulness as well as dem external reliability is obtained from calculations of water depth distributions and mean bed level results show that digital photogrammetry used in conjunction with image analysis techniques can successfully be used for extracting high resolution dems of gravel river beds in exposed areas errors are small and random tending to cancel out over large numbers of points where water is shallow and following correction point elevation errors are statistically no different from those for exposed zones in deeper water despite an improvement following application of the correction procedure elevation errors scale with water depth the geomorphological potential of photogrammetric survey of large gravel river beds is demonstrated by the ease and accuracy of calculations of water depth distribution important for the assessment of a river s ecological and recreational characteristics and mean bed level important for the calculation of reach scale sediment volumes copyright 2000 john wiley sons ltd

mineralogy micromorphology and chemical analysis of andosols on the island of sao miguel azores abstract a study concerning soil genesis was conducted on surface and buried volcanic soils of sao miguel island azores of eight soil profiles three were selected for detailed study of pedogenesis a series of techniques which include chemical micromorphological xrd and dxrd analysis micropicking on impregnated soil blocks tem eds and ir spectroscopy analyses were used the soils showed an incipient to moderate degree of weathering as typically occurs in many young volcanic districts four different stages of soil development were clearly identified the first stage of soil development was characterised by dominance of primary minerals and some allophane and ferrihydrite formation with an feo fed ratio of about 0 86 lom soil the second stage of soil development was indicated by halloysite and ferrihydrite formation in the lower horizons along with an feo fed ratio of about 0 62 san surface soil the third stage of soil development was characterized by halloysite and ferrihydrite formation in the lower horizon but also by clay illuviation and stronger pumice weathering and an feo fed ratio of about 0 51 san buried soil the fourth stage of soil development concerned the lix soils buried soils older than 5000 years bp which had a much higher content in hydrated halloysite and considerable amounts of goethite and hematite these soils exhibit the most expressed weathering features and an feo fed ratio of about 0 25 the presence of young surface soils and well developed buried soils can be explained by i the longer pedogenesis of buried soils or possibly by ii the presence of a climate more seasonal than that of the present day

difference information criterion for the analysis of a seismotectonic influence on a radon time series at the ksm site japan summary this research investigates how a difference information criterion combined with a function of observed seismotectonic activity can be used to analyse the influence of seismotectonic activity on the variation in a radon time series observed at the ksm site izu peninsula japan the difference information criterion is used to identify significant variance in the radon time series the seismotectonic activity is represented by an aggregated univariate function of seismic observations a flexible definition of the function is proposed enabling an analysis of various geometrical and energetic relations between the seismotectonic activity and the monitoring site the results are compared with previous results obtained at the same site with a different approach identifying 12 post seismic signals and one pre seismic signal to 23 earthquakes with mw 6 0 and within 1000 km hypocentral distance during the period considered the combination of a difference signal criterion and the introduced aggregation function of seismic observations is more sensitive for identifying seismotectonic related variance in the radon time series than the use of confidence intervals as proposed in former works

controls on groundwater rn 222 concentrations in fractured rock approximately 150 rn 222 analyses from groundwater wells in fractured lithologies of eastern connecticut were made to evaluate the intralithologic and interlithologic variability although there is a control of rn 222 activity in porefluids by uranium radium concentration in the host rock the variability of local rn 222 is dominated by site specific rock properties these are with their contribution to the variability i the specific fracture surface area 10 sup 3 times which is functionally dependent on crack width ii the emission efficiency 10 sup 2 times which is functionally related to the fracture spacing and iii the enrichment of uranium ra 226 on the fracture surface 10 sup 2 times thus the activity of radon in fractured lithologies is difficult to predict and the measurement of radon activity does not uniquely constrain the geometry of the rock or the chemical inhomogeneity

gravel transport and morphological change in braided sunwapta river alberta canada the relation between morphological change and patterns of variation in bedload transport rate in braided streams was observed by repeated daily topographic surveys over a 25 day study period in a 60 m reach of the proglacial sunwapta river alberta canada there are two major periods of morphological change each lasting several days and each involving the complete destruction and reconstruction of bar complexes bar complex destruction was caused by redirection of the flow and by downstream extension of the confluence scour zone upstream reconstruction involved accretion of unit bars on bar head flank and tail and in one case was initiated by disection of a large lobate unit bar high rates of sediment movement measured from net scour and fill of the cross sections coincided with these morphological changes sediment was supplied from both bed and bank erosion and patterns and distances of transfer were highly variable rates of transport estimated by matching upstream erosional volumes with downstream deposition were much greater than those estimated from either a step length approach or a sediment budget measurements of scour and fill and observations of morphological change indicate that step lengths virtual transport distances were typically 40 100m during a diurnal discharge cycle shorter step lengths occurred when transfer was confined to a single anabranch and longer steps involved channel changes at the scale of the entire reach sediment budgeting was used to describe the spatial patterns of sediment transport associated with the morphological changes and to estimate minimum daily reach averaged transport rates mean bedload transport rates correlate with discharge but with considerable scatter the largest deviations from the mean relation can be tied to phases of channel incision bank erosion scour hole migration bar deposition and channel filling apparently controlled by changes and fluctuations in sediment supply from upstream independent of discharge these are interpreted as field evidence of autopulses or macropulses in bedload transport previously observed only in laboratory models of braided streams

222rn transport in a fractured crystalline rock aquifer results from numerical simulations abstract dissolved 222 rn concentrations in ground water from a small wellfield underlain by fractured middle proterozoic pikes peak granite southwest of denver colorado range from 124 to 840 kbq m 3 3360 22700 pci l 1 numerical simulations of flow and transport between two wells show that differences in equivalent hydraulic aperture of transmissive fractures assuming a simplified two fracture system and the parallel plate model can account for the different 222 rn concentrations in each well under steady state conditions transient flow and transport simulations show that 222 rn concentrations along the fracture profile are influenced by 222 rn concentrations in the adjoining fracture and depend on boundary conditions proximity of the pumping well to the fracture intersection transmissivity of the conductive fractures and pumping rate non homogeneous distribution point sources of 222 rn parent radionuclides uranium and 226 ra can strongly perturb the dissolved 222 rn concentrations in a fracture system without detailed information on the geometry and hydraulic properties of the connected fracture system it may be impossible to distinguish the influence of factors controlling 222 rn distribution or to determine location of 222 rn point sources in the field in areas where ground water exhibits moderate 222 rn concentrations flow and transport simulations of a hypothetical multifracture system consisting of ten connected fractures each 10 m in length with fracture apertures ranging from 0 1 to 1 0 mm show that 222 rn concentrations at the pumping well can vary significantly over time assuming parallel plate flow transmissivities of the hypothetical system vary over four orders of magnitude because transmissivity varies with the cube of fracture aperture the extreme hydraulic heterogeneity of the simple hypothetical system leads to widely ranging 222 rn values even assuming homogeneous distribution of uranium and 226 ra along fracture walls consequently it is concluded that 222 rn concentrations vary not only with the geometric and stress factors noted above but also according to local fracture aperture distribution local groundwater residence time and flux of 222 rn from parent radionuclides along fracture walls

halloysite neoformation during the weathering of nephelinitic rocks under humid tropical conditions at mt etinde cameroon abstract mt etinde eruptions are dated at 0 65 ma it is located on the sw oceanic border of mt cameroon and is composed essentially of nephenilitic rocks the weathering of nephelinites has resulted in the formation of a 150 cm deep andic cambisol humic consisting of three horizons ah bw c mineral weathering was studied in detail in two profiles one p 1 developed from unaltered nephelinite nephelinite u and the other p 2 formed from hydrothermally altered nephelinite nephelinite h emphasis was on the impact of hydrothermal alterations on weathering profiles to characterise the signature of halloysite in nephelinitic regoliths and to discuss the evolution of mt etinde soils on the quaternary nephelinitic parent rocks the mineralogy of nephelinite u consists predominantly of clinopyroxene nepheline leucite hauyne titanomagnetite perovskite apatite and sphene nephelinite h differs from nephelinite u by phillipsite calcite occurrence the main weathering products are halloysites 1 nm and 0 7 nm and minor occurrence of gibbsite and hematite sem micromorphological examination coupled with microprobe analyses showed halloysites resulting from in situ alterations of feldspathoids phillipsites and clinopyroxenes 1 nm hydrated halloysite neoformation characterises the alteromorphs of the saprolite while 1 nm and 0 7 nm halloysite coexist in the bw and the ah horizons of both soils during weathering these halloysites had a chemical dependence with parent mineral as follows ce rich halloysite characterises alteromorph after phillipsite fe rich halloysite alteromorph after clinopyroxene ca rich halloysite alteromorph after hauyne and k rich halloysite alteromorph after leucite ce rich halloysite is a tracer of the hydrothermal impact in soils profile the si al ratio is also characteristic of the parent mineral therefore the availability of si is the only factor that controlled the formation of 1 nm halloysite at the base of the saprolite while the presence of 1 nm and 0 7 halloysite in the upper part of the saprolite the bw horizon and the ah horizon suggesting only time controls of the evolution of the profiles by both kinetic wet dry seasons and thermodynamic si bearing factors gibbsite occurs only in the nephelinite h soil its presence is due to the hydrothermal alteration which favoured the development of an intense microporosity allowing the elimination of silica the study highlighted the influence of past hydrothermal activity on the recent weathering process in the humid tropical area

strain on the san andreas fault near palmdale california rapid aseismic change frequently repeated strain measurements near palmdale california during the period from 1971 through 1980 indicate that in addition to a uniform accumulation of right lateral shear strain engineering shear 0 35 microradian per year across the san andreas fault a 1 microstrain contraction perpendicular to the fault that accumulated gradually during the interval 1974 through 1978 was aseismically released between february and november 1979 subsequently november 1979 to march 1980 about half of the contraction was recovered this sequence of strain changes can be explained in terms of south southwestward migration of a slip event consisting of the south southwestward movement of the upper crust on a horizontal detachment surface at a depth of 10 to 30 kilometers the large strain change in 1979 corresponds to the passage of the slip event beneath the san andreas fault

radon cl and so42 anomalies in hot spring water associated with the 1995 earthquake swarm off the east coast of the izu peninsula central japan abstract radon concentrations were continuously monitored in hot spring water in a 200 m deep well in the yugano hot spring area izu peninsula japan from july to december 1995 concentrations of cl and so 4 2 were measured in the hot spring water about once a month from may to december 1995 the rn concentrations in the hot spring water increased significantly in september and october 1995 when the 1995 earthquake swarm off the e coast of the izu peninsula occurred at a distance of about 30 km from the observation well the 1995 earthquake swarm began on 11 september and became most active from the end of september to the beginning of october the rn concentration rose gradually from 8 september 3 days before the onset of the swarm activity increasing by about 50 by 17 september it remained high in october but had returned to normal by the end of november however cl and so 4 2 concentrations doubled suddenly from 22 to 23 september and remained high until the end of november a good correlation between cl and so 4 2 concentrations suggests the same mechanism for their anomalous increases probably mixing of water with high cl and so 4 2 concentrations caused by crustal deformation related to the seismic swarm activity however the anomalous increase in rn concentration which began 15 days before these anion increases cannot be explained by the same water mixing mechanism a possible mechanism for the anomalous rn increase is the formation of microcracks caused by compressional stress which preceded the onset of the earthquake swarm

precursory behavior of groundwater radon in southeastern taiwan effect of tectonic setting in the subduction zone monitoring precursory decline in groundwater radon at the antung hot spring is a useful means of forecasting the magnitude and precursor time of local disastrous earthquakes with the help of a case study in southeastern taiwan this paper demonstrates the effect of tectonic setting in the subduction zone on the correlation between radon decline precursory time and earthquake magnitude given a radon monitoring site located near the plate boundary in the tectonic setting of advanced arc continental collision the observed radon decline and precursory time prior to the earthquakes in the tectonic setting of initial arc continental collision are smaller than those observed prior to the earthquakes occurring on the plate boundary in the tectonic setting of advanced arc continental collision in the advanced arc continental collision state the coupling between the plates is strong and the stress transfer is efficient whereas in the incipient collision state the coupling and stress transfer are not as good it also takes additional time lag and attenuation for the stress transfer from one tectonic setting to the other this paper presents the difference in the precursory behavior of groundwater radon between earthquakes which occurred in two different tectonic settings advanced and initial arc continental collision

from andic non allophanic to non andic allophanic inceptisols on alkaline basalt in mediterranean climate a toposequence study in the marghine district sardinia italy abstract the properties of a non andic allophanic inceptisol pom1 and two andic non allophanic inceptisols flm5 and spm8 representative of a toposequence on basanite rocks of mt st antonio central western sardinia marghine sub region were analyzed to better elucidate factors and processes that lead to a different expression of andic properties and allophane formation in xeric mediterranean environment a series of laboratory techniques including physical chemical micromorphological x ray diffraction xrd scanning electron microscopy sem analyses were used all soils are usually rich in organic carbon dystric at the great group level with saturation base from 72 to 10 and with ph from subalcaline to acidic allophanic inceptisol appears more intensely weathered than non allophanic inceptisols volcanic glass content is in any case negligible pom1 formed on the plateau shows a shallow solum 45 cm with a 2 horizon that meets all the criteria for andic soil properties the amounts acid oxalate extractable al o and si o together with pyrophosphate extractable al p typifies such a pedon as allophanic inceptisol 0 19 p al o 2 the allophanic inceptisol pom1 is located at the plateau of the toposequence where lower surface runoff greater water infiltration rate the absence of significant erosion and colluvial movement may have increased the degree of weathering processes in these conditions the prolonged soil moistness prevents the transformation of short order components on the whole the results emphasize the role of topography and the importance of al fe amorphous compounds in expressing soil andic properties and allophane content versus the volcanic origin of parent material and the insufficiency of volcanic glass the results also suggest that the occurrence of soil with andic properties and significant allophane content in hot and dry environments like the mediterranean climate in sardinia may be more widespread than expected

magnetic and chemical parameters of andic soils and their relation to selected pedogenesis factors in the case of andic soils developed on volcanic rocks permanently humid conditions are essential for andosolisation processes although volcanic rocks are usually rich in highly magnetic iron oxides knowledge about these minerals in andic soils with respect to the soil development is missing the aim of this contribution is to investigate the relationship between magnetic and basic chemical properties of soils developed on volcanic basement and parameters related to the pedogenesis factors the studied sites are located on basaltic lava flows in the eastern part of the french massif central investigated pedons with alu andic sil andic and vitric properties were pedologically described and analysed by a set of magnetic and soil chemical methods magnetic parameters include low field volume specific and mass specific magnetic susceptibility frequency dependent magnetic susceptibility remanent properties including s ratio and coercivities chemical parameters included the phh2o soil organic matter total cation exchange capacity base saturation and content of fe and al extracted in dithionite citrate acid ammonium oxalate and pyrophosphate solutions micro morphology of andosols and parent material was observed by scanning electron microscopy completed with energy dispersive spectrometry the pedogenesis factors are represented by parent rock age annual precipitation and soil thickness our findings suggest that 1 precipitation is the most important pedogenesis factor with a strong relationship to the relative magnetic grain size concentration of ferrimagnetic minerals aluminium dissolved in pyrophosphate and acid ammonium oxalate and content of organic matter 2 parent material age shows a well pronounced relationship with magnetic grain size parameters represented by the frequency dependent susceptibility and ratio of saturation remanent to saturation induced magnetisation mrs ms selective dissolution parameters and phh2o 3 thickness of soil profile shows a link to mrs ms phh2o and content of organic matter

research on groundwater radon as a fluid phase precursor to earthquakes groundwater radon monitoring work carried out in southern california by the university of southern california since 1974 is summarized here this effort began with a sampling network over a locked segment of the san andreas fault from tejon to cajon and was later expanded to cover part of the southern transverse mountain ranges groundwater samples were brought back weekly to the laboratory for high precision scintillation counting needs for more frequent sampling and less labor prompted the development of an economical and field worthy instrument known as the continuous radon monitor about 10 have been installed in the network since early 1980 the groundwater radon content was found to show anomalous increases mostly at a single station before a number of moderate and nearby earthquakes our work is hampered by a lack of large earthquakes that may have a regional impact on radon anomalies and by the complexity of the underground hydrological regime to circumvent this difficulty we have chosen to monitor only deep artesian wells or hot spring wells

radon emissions from mud volcanoes in northern italy possible connection with local seismicity data concerning radon emission in waters filling mud volcanoes of northern apennines northern italy sampled from 1986 until 1989 have been analyzed possible connections between shallow environmental conditions and rn emission from mud volcanoes have been explored a linear relationship between air temperature and rn count rates has been determined after the removal of temperature related rn variations a significant correlation has been pointed out between anomalous spike like rn emissions at one of the station considered and the occurrence of low magnitude m 4 5 local earthquakes

sources of iron oxides in reddish brown soil profiles from calcarenites in southern spain abstract we studied the distribution with depth of the different forms of iron in two reddish brown rubified soils developed on hematite free calcarenites in the province of cordoba southern spain hematite appeared in significant amounts in the a and b horizons of the soils and seemed to have originated mainly from the weathering of the fe bearing clay minerals smectites because of their low contents of fe both the non clay fraction and the carbonate of the parent material contributed little to fe oxide formation the distribution with depth of goethite in the clay fractions suggested that part of the initial goethite had been lost and might have been altered to hematite

terrestrial structure from motion spatial error analysis of roughness and morphology structure from motion sfm photogrammetry is rapidly becoming a key tool for morphological characterisation and change detection of the earth surface this paper demonstrates the use of terrestrial structure from motion tsfm photogrammetry to acquire morphology and roughness data at the reach scale in an upland gravel bed river we quantify 1 spatially distributed error in tsfm derived digital elevation models dems and 2 identify differences in roughness populations acquired from tsfm photogrammetry versus tls we identify an association between local topographic variation and error in the tsfm dem on flatter surfaces e g bar and terrace surfaces the difference between the tsfm and tls dems are generally less than 0 1 m however in areas of high topographic variability 0 4 m such as berm or terrace edges differences between the tsfm and tls dems can be up to 1 m our results suggest that grain roughness estimates from the tsfm point cloud generate values twice those derived from the tls point cloud on coarse berm areas and up to four fold those derived from the tls point cloud over finer gravel bar surfaces this finding has implications when using sfm data to derive roughness metrics for hydrodynamic modelling despite the use of standard filtering procedures noise pertains in the sfm dem and the time required for its reduction might partially outweigh the survey efficiency using sfm therefore caution is needed when sfm surveys are employed for the assessment of surface roughness at a reach scale

correlation of groundwater radon anomalies with earthquakes in the greater palmdale bulge area recent measurements in the central transverse ranges of southern california suggest possible correlations of changes in groundwater radon content with occurences of nearby earthquakes since measurements began in 1974 three radon anomalies have been accompanied by subsequent nearby seismic events two of these anomalies were associated with moderate sized earthquakes and one with a swarm within a 60 day window prior to the seismicity groundwater radon increased in each case at sites close to the earthquake epicenters before the big bear earthquake of june 30 1979 m 4 8 radon anomalies were found at three nearby monitoring sites groundwater radon content at one site near the january 1 1979 malibu earthquake m 5 0 showed negative as well as positive anomalies both prior to and following the earthquake a radon anomaly occurred at a nearby spring prior to the fall 1976 palmdale swarm the observed pattern is similar to pre earthquake anomalies reported from russia china and japan

monitoring channel responses to flood events of low to moderate magnitudes in a bedrock dominated river using morphological budgeting by terrestrial laser scanning abstract changes to channel morphology reflect geomorphic work by flood events of differing magnitude and frequency advances in remote sensing and digital terrain processing now allow for sophisticated analysis of spatial and temporal changes in erosion and deposition although the morphological budgeting approach using digital elevation models of difference has been widely applied to track volume estimation of changes to erosion and deposition over time appraisals of geomorphic effectiveness in high energy confined and partly confined channels are still lacking this study applied terrestrial laser scanning to monitor three reaches of the liwu river a bedrock dominated river in eastern taiwan from 2009 to 2012 to investigate channel responses to flood events of low to moderate magnitude and appraise their geomorphic effectiveness variability in geomorphic effectiveness reflected valley confinement and the composition configuration of geomorphic units on the channel bed annual low magnitude flood events reworked gravel and sand deposits creating local scour and fill

radon changes associated with the earthquake sequence in june 2000 in the south iceland seismic zone an earthquake sequence at the transform plate boundary in south iceland that included two magnitude 6 5 earthquakes in june 2000 was anticipated on the basis of a centuries long seismicity pattern in the area a program of radon monitoring in geothermal water from drill holes initiated in 1999 rendered distinct and consistent variations in radon in association with these events all seven sampling stations in a 50 30 km zone covering the epicentral area showed a consistent pattern four types of change could be identified 1 preseismic decrease of radon anomalously low values were measured 101 167 days before the earthquakes 2 preseismic increase spikes appear in the time series at six stations 40 144 days prior to the earthquakes these anomalies were large and unusual if compared to a 17 years history of radon monitoring in this area 3 coseismic step most likely related to the coseismic change in groundwater pressure observed over the entire area 4 postseismic return of the radon values to the preseismic level about three months later also concurrent with groundwater pressure changes

the weathering of volcanic tephra and how they impact histosol development an example from south east iceland abstract little is known about the impact of tephra deposits from explosive volcanic eruptions on soil formation and weathering processes in organic soils the weathering of tephra of basaltic and rhyolitic origin and their impact on icelandic histosols were studied through a combination of physical chemical and mineralogical analyses two sampling sites were selected according to the presence of the light coloured rhyolitic tephra from the oraefajokull eruption in 1362 ce and a dark coloured basaltic vei ivotn tephra from 1477 ce in the volcanically active area south of vatnajokull in south east iceland the determining factor of pedogenesis in the investigated histosols is the om but the influence of tephra and aeolian material from external sources must be taken into consideration the soils are the result of altered plant residues and volcanic material tephra and aeolian material plant remnants as well as the soil itself are protected from decomposition by the prevailing anaerobic conditions a low soil ph and the repeated addition of inorganic matter clay formation is low while metal humus complexes are predominant feo fed ratios indicated a generally low degree of weathering being higher close to the basaltic tephra the mineralogy was dominated by plagioclase and pyroxene with quartz and zeolite as minor components in contrast to previous research on icelandic soils our investigations revealed layer silicates at both sites while we found evidence of smectite in the soils at kalfafell hydroxy interlayered minerals were found at reynivellir in the basaltic tephra traces of layer silicates could be verified in contrast the rhyolitic tephra did not show any pedogenic minerals suggesting that it had hardly altered since its deposition in 1362 ce it is not the chemical composition of the inorganic parent material but the location that may be an influencing factor on the formation of clay minerals in the investigated histosols

mineralogical and geo chemical characterization of a diapiric formation in the north of spain abstract we have selected seven profiles located in a diapiric formation in the north of spain the profiles have been analyzed for the mineralogy and the chemical composition of original materials soils developed above them and clay fractions three soils formed on basic rock of volcanic origin ophite and rich in alterable minerals three others formed on clay marl and one soil formed on gypsiferous marl plagioclases pyroxenes vermiculites and biotites are the main minerals found in the soil samples and ophitic rocks biotite smectite chlorite and interstratified chlorite vermiculite make up the predominant mineralogical association in the clay fraction of the soils calcite biotite and on top of all chlorite are the main minerals in the marls and the soils developed on them with gypsum predominant in the gypsiferous marl the mineralogy of its clay fraction is comprised mainly of chlorite and biotite the variations in content of al2o3 tio2 and na2o in the ophites are considered to be associated with the differences in the evolution of the pyroxenes the variability of the chemical composition of the keuper sediments and the soils is attributed more to the chaotic disposition of the triassic materials in the formation of the diapir than to intense chemical weathering the low concentrations of silica iron and aluminum extractable with ammonium oxalate indicate the low proportion of non crystalline products fundamentally it is the semiarid conditions in the study zone together with the processes of extrusion and hydrothermal activity affecting the formation of the diapir that are responsible for the genesis of the minerals

volcanic soil formation in calabria southern italy the cecita lake geosol in the late quaternary geomorphological evolution of the sila uplands abstract this paper focuses on the main morphological physical chemical and mineralogical features of an andic like soil widely outcropping in the sila upland plateau of calabria southern italy and its potential role in tephrostratigraphy a multidisciplinary and multiscale approach allowed identification of this soil as a masked distal archive of volcanic products developed on granite rocks and sediments with a coeval pyroclastic input during pedogenesis the study demonstrates that the contribution of volcanic parent materials can be successfully hypothesized and assessed even in the absence limited extent or poor preservation of primary eruptive products the soil has an andisol like appearance despite laboratory data that do not match the entire suite of diagnostic criteria for the andisol taxonomic order geomorphological stratigraphic and pedologic results coupled with tephrostratigraphic and radiometric data concur to suggest a late pleistocene to holocene age of the andisol like soil in particular the rhyolitic chemical composition of small sized glass fragments identified by sem eds analyses indicates soil genesis contributed by volcanic ash probably sourced from aeolian arc explosive activity spanning the last 30 ka accordingly the evidence of limited relict clay illuviation and the specific type of pedogenesis allowing the development of andic properties in turn related to the neoformation of clay minerals from the weathering of volcanic glass are consistent with a climatic shift from a seasonally contrasted to a constantly humid pedoenvironment this change can be ascribed to the lateglacial or early middle holocene to late holocene transition calibrated ams 14 c dates performed on charcoal fragments sampled from three representative soil profiles provide late holocene ages 3136 19 343 16 and 92 24 yr bp in accord with archaeological finds on the basis of the consistent stratigraphic position lateral continuity and wide extent the soil can be considered a good pedostratigraphic marker in the sila highlands and is informally defined as the cecita lake geosol it supplies valuable time constraints for the underlying occasionally overlying deposits and or soils moreover it allows regional scale morphostratigraphic correlations and detailed reconstruction of late pleistocene holocene geomorphic events in calabria a very suitable region for distal tephra deposition in the central mediterranean peri volcanic area the effects of high energy volcanic eruptions are interfingered with or superimposed by other geomorphic processes and climatic or anthropogenic signals

a stress condition in aquifer rock for detecting anomalous radon decline precursory to an earthquake recurrent groundwater radon anomalous declines were observed from well measurements in the antung hot spring area eastern taiwan prior to five of six earthquakes that occurred between 2003 and 2011 m w range 5 0 6 8 the relationship between the detectability of radon anomalies and the first motions of p waves was investigated based on the first motions of p waves recorded near the investigated well a precursory decrease in groundwater radon can be detected only when the first motion is compression no precursory change in groundwater radon concentration was observed for the downward first motion of p waves

geochemical monitoring in the marmara region nw turkey a search for precursors of seismic activity 1 physical and chemical properties of warm and hot spring waters as well as soil radon concentrations were measured continuously during a 3 year period in the marmara region following the devastating izmit earthquake of 17 august 1999 mw 7 4 promising and encouraging anomalies in ground radon emanation have been recorded and found to be closely related to seismic activity the temporal and spatial variations in the soil radon data are presented the earthquakes with magnitude 4 in the region were correlated with positive radon anomalies furthermore during quiescence absence of seismic activity the radon data indicate random walk behavior of radon in soil and show rayleigh type probability density function pdf however during the earthquake build up period the data show deviations from rayleigh type pdf the radon positive anomalies indicate disturbance of the path of gas movement or gas release pattern prior to earthquakes however systematic and consistent anomalies in physical and or chemical properties of the spring waters have not been detected for earthquakes occurring in the observation period m 5 3

characterization functioning and classification of two volcanic soil profiles under different land uses in central mexico volcanic soils constitute an important resource for agriculture and forestry in central mexico as well as in various world regions they exhibit unique properties and high productive potential related to the amorphous materials they contain the relationship between amorphous materials soil characteristic and functioning has not been well studied the objectives of the present work were to assess the influence of land use agricultural and forest topography and other soil forming factors on physical chemical and mineralogical characteristics and pedological processes responsible for soil genesis and soil classification of two volcanic soil profiles derived from andesitic parent material located 150 m away from each other within the same toposequences the toposequence is located in the trans mexican volcanic belt tmvb a highly populated region of central mexico that provides part of the water for mexico city megapolis a series of field and laboratory techniques including physical chemical micromorphological x ray diffraction xrd transmission electron microscopy tem infra red analysis mossbauer spectroscopy were used the main factor affecting the present morphology of the soil profiles was the topography the mineralogical features of the upper layers of the maize profile pachic andosol indicate redistribution of soil material from the upper part of the toposequence the land use change favored this redistribution deeper horizons of this profile were developed from volcanic ashes deposited in situ hematite and ferrihydrite considered markers of evolution in redistributed soil material were observed in this profile associated with allophane the presence of hematite has been reported for the first time in mexican andosols the present characteristics of the forest profile dystric cambisol are mainly due to the pedological process of the volcanic ash layers remaining in situ after the redistribution and volcanic breccia it was concluded that the forest profile evolved from an andosol to an inceptisol which was evidenced by desaturation loss of silica and organic carbon in this profile the fe minerals were associated with the presence of gibbsite and halloysite the position in the toposequence and the physical and chemical characteristics of these profiles define their present functioning such as losses by erosion and c dynamics

iron oxides and clay minerals within profiles as indicators of soil age in northern italy abstract nine profiles representing the alfisol inceptisol and entisol orders were sampled on three terraces forming a chronosequence total iron dithionite extractable iron and oxalate extractable iron were determined for all horizons of all profiles and the clay mineralogy for horizons of three profiles the percentage of total fe fet extracted by dithionite fed increased with age of terraces as did the difference between fed and feo oxalate extractable analysis of variance anova of the horizon data showed that the ratios fed fet and fed feo fet were closely related to the ages of the terraces clay minerals were also related to terrace ages with 2 1 minerals dominant in the profiles on the youngest and mixed layer minerals and kaolinite more abundant in profiles on the older terraces

cdw photogrammetry of low relief fluvial features accuracy and implications for reach scale sediment budgeting terrestrial photogrammetry enables rapid survey to be undertaken in the fluvial environment a crucial factor when assessing highly dynamic features in addition it permits the generation of terrain surfaces at a level of detail which given equal time constraints in the field far exceeds the detail permitted by conventional tacheometric survey this study details the levels of accuracy that can be achieved using the rolleimetric close range digital workstation cdw photogrammetric survey technique on a variety of low relief fluvial geomorphic features lateral point and mid channel bars ranging from 10 m 2 to 100 m 2 the cdw software processes image data from an array of photographs and establishes a set of three dimensional co ordinates for the photographed object the accuracies achieved across all bar surfaces were well within the resolution defined by the maximum size of the gravel on the bar surface mean errors were between 0 026 and 0 057 m the use of cdw photogrammetry does not require experienced personnel however care must be taken during the survey to minimize edge effects and to ensure that target density is sufficient to produce a terrain model that is accurate to within the limits of the surface sediment size guidance on target density as a function of terrain roughness is given to aid the user a methodology is suggested that will allow cdw to be incorporated into sediment budgeting techniques improving the level of achievable accuracy 1998 john wiley sons ltd

radon and hydrologic anomalies on the rough creek fault possible precursors to the m5 1 eastern kentucky earthquake 1980 soil radon emanation increased sharply on the rough creek fault near the illinois kentucky border in april 1980 3 1 2 months before a m5 1 earthquake in eastern kentucky july 27 1980 the spikelike anomaly was similar to a radon anomaly in the new madrid seismic zone in 1979 that preceded by 2 months a m3 9 tremor at the site of that anomaly weekly radon monitoring was initiated on the rough creek fault after abrupt cessation of spring flow on the fault occurred at a site that had experienced similar flow cessation 1 month prior to a m5 3 earthquake in southeastern illinois in 1968 although the recent kentucky epicenter was 380 km east of the site of the detected radon anomaly factors relating to regional structures recent seismicity additional radon data and the stress regime suggest that the hydrologic and radon anomalies may have been precursors to an eastward progression of strain that culminated in the eastern kentucky tremor

a new procedure for gridding elevation and stream line data with automatic removal of spurious pits abstract a morphological approach to the interpolation of regular grid digital elevation models dems from surface specific elevation data points and selected stream lines is described the approach has given rise to a computationally efficient interpolation procedure which couples the minimization of a terrain specific roughness penalty with an automatic drainage enforcement algorithm the drainage enforcement algorithm removes spurious sinks or pits yielding dems which may be used to advantage in hydrological process studies the drainage enforcement algorithm has also been found to significantly increase the accuracy of dems interpolated from sparse but well chosen surface specific elevation data moreover it facilitates the detection of errors in elevation data that would not be detected by more conventional statistical means and forms a sound physical basis for cartographic generalization

gas geochemistry and seismotectonics a review abstract publications on soil and spring gases have been examined regarding their relationships with both tectonic and seismic activities the main sources behaviours and uses of species detected in soils and springs are displayed and their mode of sampling and analysing briefly described the main patterns of degassing in soils are described and we outline the wide range of geochemical signatures as the result of both permeability and mineralogical contrasts because thermomineral waters have been in contact with great volumes of crustal rocks at various depths spring gases might be more representative of the local environment than soil gases moreover gas signature comparisons show that spring gases are much more enriched with deep gases and slightly contaminated by atmospheric gases therefore they can be considered as better samples for identifying precursors of earthquakes environmental perturbations are examined and it is shown from divergent cases that pressure temperature soil moisture or earth tides may generate very high perturbations of the degassing process such effects demonstrate that no systematic correction law can be proposed and that removing external contributions from gas concentrations must be performed case by case this demonstrates therefore the need for the simultaneous measurement of external parameters during gas monitoring a qualitative examination of about 150 claimed precursors proposed in the literature has been reviewed as noted by previous authors anomalies appear at distances sometimes much greater than typical source dimensions and occur in the field of strain higher than 10 9 most of them being in the field of strain higher than 10 8 taking into account the very high heterogeneity of such a set of data we can suggest that amplitudes of gas anomalies are independent of both magnitudes and epicentral distances of related earthquakes suggesting local conditions to control amplitudes on the contrary precursory time and duration of anomalies seem to increase both with magnitudes and epicentral distances abundant evidence demonstrates the major role of crustal fluids in the earthquake cycle many works have outlined the fact that crustal instabilities can appear as the result of low stress strain perturbations during loading it has been suggested that motion of fluids may occur at various scales from microcrack fluid transfer up to changes of hydraulic levels of water tables the study of subsequent anomalies is expected to supply a tool for earthquake prediction following previous authors we outline the need for further methodological improvements including the setting up of multiparameter station networks and the simultaneous recording of the main external parameters atmospheric pressure water and air temperature soil moisture for signal processing

development and spatial distribution of soils on an active volcano mt etna sicily abstract as a large active volcano mt etna presents a complex soil forming environment with a spatial diversity of lava flow age tephra deposition local climate and agriculture following a review of previous published research on etna s soils this paper analyses physical and chemical data for 23 profiles between 120 m and 1030 m elevation on all flanks of the volcano with the aim of characterising the soils and determining the extent to which the chief controls on their nature and geography may be identified soils are sampled across a chronosequence of lava flows dating from 72 yr to between 28 ka and 42 ka bp which occur in conditions of diverse land use and local climate ages of flows 3000 yr are only broadly constrained the majority of soils comprise mostly tephra chief soil processes inferred have been identified in previous published research on mt etna accumulation of soil organic matter rapid loss of na and production of fine grained materials particularly those inferred to be of short range order other developments are soil structural formation and evidence of increasing soil mesofaunal activity despite the complexity of environmental diversity and spatial variation in tephra deposition a number of soil properties including material

radon content of groundwater as an earthquake precursor evaluation of worldwide data and physical basis the properties of a worldwide data set of 91 radon 222 rn anomalies the frequency of occurrence the precursor time interval and the distribution of peak amplitudes are correlated with earthquake data such as the respective magnitude and epicentral distance these anomalies were reported as precursors to earthquakes in the united states ussr china japan and iceland although the data set is incomplete and limited by experimental deficiencies several consistent patterns emerge radon anomalies from different tectonic regions show similar patterns the radon anomalies occur at greater epicentral distances for earthquakes of the larger magnitude anomalies preceding large earthquakes m 6 are frequently observed at a distance of 100 to 500 km these distances are larger than several times the rupture dimensions of the future earthquakes the time from the onset of an anomaly to the time of the earthquake the precursor time increases with magnitude but decreases with distance between epicenter and radon station in addition radon anomalies are observed more frequently prior to large earthquakes than prior to small ones indicating that the preparation zone increases in size as magnitude increases the peak amplitude does not scale with magnitude but forms a consistent pattern with epicentral distance in that the larger the earthquake magnitude the farther away the largest amplitudes tend to occur the preparation zone of the earthquake where the anomalies occur forms an almost continuous annulus that expands with time away from the future rupture zone the outer radius of this annulus scales with the earthquake magnitude model calculations indicate that strain fields of at most 10 6 to 10 8 strain caused the radon anomalies if these strains are divided by the appropriate precursor time minimum strain rates from 10 7 day 1 to 10 10 day 1 are obtained such small strains and strain rates suggest that in most cases neither mechanical crack growth induced by dilatancy nor mechanical coupling between pore pressure and the rock matrix caused the anomalies large changes in the orientation of the local strain field however could occur and affect the local stress intensity factor since changes in the stress intensity factor can result in stress corrosion the occurrence of radon anomalies is attributed to slow crack growth controlled by stress corrosion in a rock matrix saturated by groundwater

evaluating short term morphological changes in a gravel bed braided river using terrestrial laser scanner abstract braided rivers are dynamic and complex environments shaped by the balance of the flow and sediment regimes and by the influence of the riparian vegetation and disturbances such as floods in particular the balance between sediment supply and transport capacity can determine the morphological evolution of a river for instance aggrading and widening trends are distinctive of reaches where sediment supply is higher than transport capacity in contrast incising and narrowing tendencies are dominant the aim of the present study is to analyze the short term morphological dynamics and the processes of erosion and sediment deposition along a small reach of a relatively unimpacted gravel bed braided river tagliamento river northeast italy using a terrestrial laser scanner tls the study area is around 23 ha and has been surveyed before after two periods with relevant flood events two of which were higher than the bankfull level and occurred between september 2010 and september 2011 the very high point clouds density allowed us to derive three high resolution digital elevation models dems with 0 125 0 125 m pixel size scan data cloud merging was achieved with an overall high degree of accuracy and resolution subcentimeter topographic data were more accurate for exposed surfaces than those collected in wet areas a detailed net of dgps control points allowed us to verify the high quality of the dems derived from the surveys rmse of about 5 cm two dems of difference dod were computed revealing different and consistent episodes of erosion and deposition within the analyzed area and changes in morphology of channel and bars could also be detected such as bar edge accretion and bank erosion demonstrating a strong dynamicity of the tagliamento river moreover a very detailed estimation of the surface roughness in the study area has been carried out permitting a large scale analysis of the roughness values distribution the results of the analysis on the tls collected data show that along a river with a high natural character i e tagliamento river the dynamic processes are also common during low magnitude events

microscale characterization of rupture nucleation unravels precursors to faulting in rocks abstract precursory signals manifestations of microscale damage that precedes dynamic faulting are key to earthquake forecasting and risk mitigation detections of precursors have primarily relied on measurements performed using sensors installed at some distance away from the rupture area in both field and laboratory experiments direct observations of continuous microscale damage accumulated during fault nucleation and propagation are scarce using an x ray transparent triaxial deformation apparatus we show the first quantitative high resolution three dimensional 3d information about damage evolution of rocks undergoing brittle failure the dynamic microtomography images documented a spectrum of damage characteristics and different fault growth patterns the interplay between various deformation mechanisms can result in either a positive negative or constant net volume change consequently changes in rock density and acoustic wave velocities before faulting are expected to vary in different tectonics settings hence making failure forecasting intrinsically dependent on rock type at depth

comparative study of 222rn 40ar 39ar and 37ar leakage from rocks and minerals implications for the role of nanopores in gas transport through natural silicates we have measured the leakage of radiogenic 222rn and 40ar and reactor produced 39ar and 37ar in samples of granites plagioclase orthoclase cleavelandite and hornblende to assess the role of nanopores in gas transport through them the 39ar and 37ar were produced by fast neutron irradiation of the samples in vacuum sealed ampoules the leakage of all three ar isotopes was barely measurable in contrast the leakage of 222rn ranged between 1 45 18 1 orders of magnitude higher than that of the ar isotopes the extremely low ar isotope leakage suggests that the samples studied are not permeated by extensive nanopore networks which intersect grain surfaces the relatively high 222rn loss from these samples therefore has to be attributed to preferential enrichment of 226ra 238u on grain surfaces or to the existence of u th accessory minerals in or around grain boundaries from which substantial quantities of 222rn escape

time variable response characteristics of groundwater radon to earthquakes a clear coseismic anomaly of groundwater radon was observed for a magnitude 5 6 earthquake that occurred on may 11 1992 the coseismic radon anomaly was observed at a station which is located right on a major active fault in northeast japan and about 140 km away from the hypocenter this was the first time that an earthquake with m 6 had ever been accompanied by a clear radon anomaly at the station although we had observed 12 similar coseismic radon anomalies at the station during the observation period from 1984 to 1987 all of the earthquakes that were accompanied by radon anomalies in that period had been with magnitude 6 0 and over surprisingly the radon concentration has become more sensitive to show coseismic anomalies even for m 5 earthquakes since october 1992 this enhancement of sensitivity of the coseismic radon response may be attributed to the progress of micro crack formation in the fracture zone of the active fault which could be related to unusual stress accumulation in the region

clay formation and pedogenetic processes in tephra derived soils and buried soils from central southern apennines italy abstract volcanic activity in central southern italy produced pyroclastic deposits that covered large areas of the apennine mountains the major volcanic centres include roccamonfina campi flegrei phlegraean fields and somma vesuvius the properties of six soils formed in volcanic tephras in the matese massif were analysed to shed light on processes that lead to different expressions of andic properties in a mountain environment andosols at 1600 m a s l at campitello matese are strongly acidic and rich in organic carbon not only in the subsurface horizons but also in buried horizons these pedons have horizons that meet all the criteria for non allophanic andosols and have modest contents of gibbsite and short range ordered fe minerals such as ferrihydrite pedons at lower altitudes of 830 m a s l at colle santa croce developed on different pyroclastic materials and contain well crystallized secondary minerals and have clay contents up to 30 the general sequence of pyroclastic deposits and distribution of upland andosols in the matese massif suggests that volcanic ash and possibly neapolitan yellow tuff are the main soil parent materials in the upper mountains by contrast the andosols developed at lower altitude at colle santa croce were most likely influenced by geomorphologic deformation of a sequence of relict of lacustrine deposits related to old volcanic activity at roccamonfina that occurred 437 1 9 ka buried horizons of these pedons lack andic properties and contain sepiolite that originated from weathering in an alkaline lacustrine environment mineralogical and chemical data for the colle santa croce pedons suggest that andosols developed as non allophanic aluandic andosols and as a result contain mainly al and fe humus complexes with poorly crystalline active al and fe phases buried soil horizons at campitello matese contain gibbsite which suggests that these horizons weathered at the soil surface for relatively long periods before being buried by subsequent ash falls over the past 39 ka soils formed in volcanic ash may be more widespread in the apennine mountains than currently believed and they may be more widespread in other mountainous areas of italy as well

role of the brittle ductile transition on fault activation abstract we model a fault cross cutting the brittle upper crust and the ductile lower crust in the brittle layer the fault is assumed to have stick slip behaviour whereas the lower ductile crust is inferred to deform in a steady state shear therefore the brittle ductile transition bdt separates two layers with different strain rates and structural styles this contrasting behaviour determines a stress gradient at the bdt that is eventually dissipated during the earthquake during the interseismic period along a normal fault it should form a dilated hinge at and above the bdt conversely an over compressed volume should rather develop above a thrust plane at the bdt on a normal fault the earthquake is associated with the coseismic closure of the dilated fractures generated in the stretched hangingwall during the interseismic period in addition to the shear stress overcoming the friction of the fault the brittle fault moves when the weight of the hangingwall exceeds the strength of the dilated band above the bdt on a thrust fault the seismic event is instead associated with the sudden dilation of the previously over compressed volume in the hangingwall above the bdt a mechanism requiring much more energy because it acts against gravity in both cases the deeper the bdt the larger the involved volume and the bigger the related magnitude we tested two scenarios with two examples from l aquila 2009 italy and chi chi 1999 taiwan events gps data energy dissipation and strain rate analysis support these contrasting evolutions our model also predicts consistently with data that the interseismic strain rate is lower along the fault segment more prone to seismic activation

quantification of braided river channel change using archival digital image analysis historical archives of grey scale river channel imagery are extensive here we present and test a methodology to extract detailed quantitative topographic date from such imagery of sand bed rivers extracting elevation information from rivers is difficult as they are characterized by a low relative relief less than 4 m the area of interest may be spatially extensive e g active channel widths 500 m in large braided rivers the rate of change of surface elevation is generally low except in the vicinity of individual channel banks where the rate of change is very high there is the complication that comes from innundation and there may be an added complication caused by blockage of the field of view by vegetation here we couple archival photogrammetric techniques with image processing methods and test these for quantification of sand bed braided river dynamics illustrated for a 500 m wide 3 km long reach of the spouth sasketchewan river canada digitial photogrammetry was used to quantify dry areas and water edge elevations a methodology was then used to calibrate the special signature of inundated areas by combining established two media digital photogrammetric methods and image matching this allowed determination of detailed depth maps for inundated area and when combined with dry area data creation of depths detectable from sequential digital elevation models the result was a series of elevation models that demonstrate the potential for acquiring detailed and precise elevation data from any historical aerial imagery of rivers without needing associated calibration data provided that imagery is of the necessary scale to capture the features of interest we use these data to highlight several aspects of channel change on the south saskatchewan river including bar movement bank erosion and channel infilling

paleosols provide sedimentation relative age and climatic information about the alluvial fan of the river tirso central western sardinia italy four representative paleosols in the plio pleistocene alluvial fan of the river tirso central western sardinia italy were studied for paleoenvironmental information to describe the sedimentology of the alluvial fan and to define a relative chronological framework for the fan the representative depositional units and associated paleosols were characterised by fieldwork physical chemical and mineralogical analyses pedogenesis was mostly driven by the time and climate factors in the proximal fan location pedogenesis was initially influenced by a warm subtropical tropical climate of the late pliocene and subsequently by warm and humid interglacial phases of the pleistocene these phases were also responsible for soil formation in the middle fan in the distal reaches of the fan pedogenesis was driven by the different climatic pulses of the late pleistocene tyrrhenian interglacial mis 5 pleistocene eustatic sea level changes directly influenced the lowest elevations of the middle fan and the distal fan erosion and soil truncation mainly occurred in the proximal fan and at the highest elevations of the middle fan during glacial phases

microplate boundaries as obstacles to pre earthquake strain transfer in western turkey inferences from continuous geochemical monitoring abstract warm and hot spring water chemistry changes as well as soil gas radon release patterns have been monitored in western turkey alongside regional seismicity providing a multi disciplinary approach from january 2009 to may 2011 33 earthquakes with ml between 4 0 and 6 0 occurred in this seismically very active region the ml 6 0 earthquake occurred on 19 may 2011 in simav town of kutahya province at a location midway between dense multidisciplinary monitoring networks of marmara region mr and the aegean extensional province aep we previously reported on noteworthy precursory anomalies prior to several earthquakes ml 4 in the mr and aep but no precursory anomaly was detected prior to the ml 6 0 event on 19 may 2011 in simav kutahya province midway between dense multidisciplinary monitoring mr and aep networks although these networks operate within the theoretical strain radii of this earthquake dobrovolsky et al 1979 no reliable anomaly were found geodetic studies based on gps data have identified crustal blocks in this region the epicentral area of the simav event is located within a block tectonically separated from aep and mr thus we speculate that pre earthquake strain accumulation within the simav block did not effectively transfer to adjacent blocks where the mr and aep networks are located thereby providing an explanation for the absence of detectable anomalies moreover prior to some earthquakes quadrant features of geochemical transients have been found suggesting that soil radon anomalies appear in compressional quadrant s of pre earthquake strain distribution

increase in radon emission due to rock failure an experimental study 1 radon anomalies are commonly observed prior to dynamic failure in the crust and are interpreted as cracking of the medium thus attracting considerable attention in understanding the precursory phenomena of earthquakes and volcanic activity in this study we have compared the starting radon emissions from low porosity crystalline lava phonolite samples with those from damaged and failed samples the damaged sample was loaded up to just beyond the end of the linear elastic phase as evidenced by the output of ae energy the increase in total porosity and a decrease in p wave and s wave velocity relative to the intact sample whereas the failed sample showed deformation behaviour characteristically brittle with increasing values of ae output and porosity as the sample approached macroscopic failure radon measurements have evidenced that dilatational microcracking of deformed sample produced no significant variation in radon emanation with respect to the intact sample in contrast after macroscopic failure radon emanation drastically increased therefore major finding from this study is that in the case of low porosity and relatively high strength crystalline lavas the development of a macroscopic fracture provides new large exhaling surface resulting in a substantial increase in radon emission rate

radon concentrations in soil gas considering radioactive equilibrium conditions with application to estimating fault zone geometry a calculation method for determining the amount of rn isotopes and daughter products at the start of measurement cras is proposed as a more accurate means of estimating the initial rn concentration in soil gas the cras utilizes the decay law between 222rn and 220rn isotopes and the daughter products 218po and 216po and is applicable to scintillation counter measurements as rn is both inert and chemically stable it is useful for fault investigation based on the soil gas geochemistry however the total number of particles emitted by the decay of rn has generally been considered to be proportional to the initial rn concentration without considering the gas condition with respect to radioactive equilibrium the cras method is shown to be effective to derive rn concentration for soil gases under both nonequilibrium conditions in which the total number of decays increases with time and equilibrium conditions which are typical of normal soil under low gas flux the cras method in conjunction with finite difference method simulation is applied to the analysis of two active fault areas in japan and it is demonstrated that this combination could detect the sharp rises in 222rn concentrations associated with faults the method also allows the determination of fault geometry near the surface based on the asymmetry variation of the rn concentration distribution when coupled with a numerical simulation of 222rn transport the results for the new method as applied to the two case studies are consistent with the data collected from the geological survey it implies that the cras method is suitable for investigating the fault system and interstitial gas mobility through fractures the present analyses have also demonstrated that high rn concentrations require the recent and repeated accumulation of 222rn parents 230th and 226ra in fault gouges through deep gas release during fault movement

ground water radon anomaly before the kobe earthquake in japan radon concentration in ground water increased for several months before the 1995 southern hyogo prefecture kobe earthquake on 17 january 1995 from late october 1994 the beginning of the observation to the end of december 1994 radon concentration increased about fourfold on 8 january 9 days before the earthquake the radon concentration reached a peak of more than 10 times that at the beginning of the observation before starting to decrease these radon changes are likely to be precursory phenomena of the disastrous earthquake

is there holocene reddening hematite formation in soils of axeric temperate areas alfisols on calcareous glacial gravels in the northern forelands of the alps between the upper rhine valley in the west and eastern bavaria in the east show rubified bt horizons their redness decreases from west 2 5 yr to east 10 yr paralleling decreasing temperature and increasing rainfall detailed mineralogical studies by mossbauer spectroscopy and differential x ray diffraction demonstrated the presence of hematite in association with goethite concentrations of hematite decrease from west to east with decreasing temperature no hematite was detected in the non calcareous residues of calcareous c horizons alfisols on silty glacial material in the immediate vicinity of the reddish soils have yellow brown 10 yr bt horizons and are hematite free we conclude that rubification hematite formation is possible under an axeric climate provided a suitable pedoclimate exists

ferrihydrite and allophane in four andepts from hawaii and implications for their classification abstract the mineralogy and composition of the waimea kukaiau akaka and hilo soils on the island of hawaii were studied using methods which included moessbauer spectroscopy and chemical dissolution the hilo soil which experiences 3000 mm year rainfall and the akaka soil 3800 mm year rainfall both contain large amounts about 25 of iron oxides of short range order together with other iron oxides gibbsite and allophane the iron oxides of short range order have characteristics similar to those of the reactive mineral ferrihydrite which is known to occur in a wide range of soils these characteristics however in two respects x ray diffraction and acid oxalate solubility do not rule out the presence or admixture of the much less known feroxyhite another closely related iron oxide of short range order most samples from these two soils dry irreversibly to give hard aggregates a property probably related to the presence of the iron oxides of shortrange order both the hilo and the akaka soils are classified as hydrandepts in the current usda soil taxonomy in the new proposed order of andisols these two soils would become hydrudands it is desirable to recognise the presence of short range order iron oxides in these soils the kukaiau soil currently classified as a dystrandept which occurs in a lower rainfall zone 1500 mm year contains about 25 allophane and lesser amounts of ferrihydrite other iron oxides and gibbsite the waimea soil occurs in the lowest rainfall zone 1000 mm year and the dominant mineral is halloysite but some allophane ferrihydrite and hematite are also present this soil is currently classified as a eutrandept under the andisol proposal the kukaiau and waimea soils would be a hapludand and a haplustand respectively quartz mica and other layer silicates were present in all four of the soils suggesting that there have been additions of eolian material

characterisation of andosols from laacher see tephra by wet chemical and spectroscopic techniques ftir 27al 29si nmr abstract at 12 900 a bp the eruption of the laacher see volcano generated a new parent material for holocene soil formation in parts of western germany weathering of these ashes commonly includes the formation of poorly crystalline minerals such as allophane imogolite and ferrihydrite detection of these minerals in soil is difficult yet an important task because they may govern soil functions and processes e g stabilisation of organic matter and nutrient availability therefore we characterised three forested andosols by a combination of wet chemical and spectroscopic techniques including infrared and 27 al 29 si nuclear magnetic resonance nmr spectroscopy together with x ray diffractometry deconvoluting the 29 si nmr spectra revealed that 1 6 to 10 4 of total si was present as allophanic compounds which coincided with the amounts of oxalate extractable si since extraction methods are not completely selective we observed a slight overestimation of allophanic si estimated from oxalate extraction although the sites under study are located close to each other in similar relief positions and with similar vegetation the combination of our results revealed varying amounts of loess in the parent materials and varying weathering intensity high weathering intensities correlate with the amounts of allophane

mineralogy of some italian andosols with special reference to the origin of the clay fraction abstract the mineralogy of four italian andosols derived from volcanic material either oversaturated or undersaturated with respect to silica has been investigated by xrd em and ir the crystalline clay minerals in all four profiles are essentially similar consisting of abundant halloysite with moderate illite and 14a intergrade material minor kaolinite and occasional gibbsite the soils also contain large amounts of imogolite and proto imogolite allophane with the exception of illite all these clay minerals are believed to be of pedogenic origin halloysite occurs in the dehydrated form in the surface horizons but becomes progressively more hydrated with depth at depths of 1 4 m the clay fraction consists almost entirely of fully hydrated halloysite supporting the suggestion that halloysite forms best in a stagnant moisture regime where there is a depositional overburden acting as a silica source em observations show that the halloysite may have spherical morphology and may be intimately associated with gas vesicles in pumice grains where it probably forms by the transformation of allophanic material it seems likely that dehydrated halloysite slowly converts to poorly crystallized kaolinite in the upper horizons of these profiles the origin of the 2 1 minerals is more problematical illite is probably inherited from mica in the parent material but the 14a intergrade material is so poorly ordered that a pedogenic origin seems more likely than formation by inheritance or by transformation of pre existing 2 1 silicates

gas geochemistry applied to earthquake prediction an overview terrestrial gases in groundwater and soil air have been extensively studied in recent years in seismically active areas especially in ussr china japan and united states in search of premonitory changes that might be useful for earthquake prediction concentrations of radon helium hydrogen mercury carbon dioxide and several other volatiles have been found generally to be anomalously high along active faults suggesting that the faults may be paths of least resistance for the terrestrial gases generated or stored in the earth to escape to the atmosphere temporal gas concentration changes with durations of a few hours to many months have been observed before many large earthquakes at a relatively small number of favorably situated stations at epicentral distances of up to several hundreds of kilometers these sensitive stations are generally located along active faults especially at intersections or bends of faults or some other structurally weak zones possibly because of tectonic strain concentration at such places however gas concentrations especially those measured at or near the ground surface may also be significantly affected by meteorological hydrological and other nontectonic changes in the environment the nontectonically induced variations must be carefully eliminated or recognized in the search of true earthquake related anomalies

modern and last glacial maximum eolian sedimentation patterns in the atlantic ocean interpreted from sediment iron oxide content eolian dust derived from the desert regions of north africa is blown far into the tropical atlantic ocean by persistent easterly and northeasterly winds in this paper we demonstrate that the iron oxides hematite and goethite are a worthwhile addition to proxy monitors of eolian sedimentation in the tropical atlantic iron oxides are identified by diffuse reflectance spectrophotometry a technique capable of identifying these minerals in concentrations as low as 0 01 by weight we analyze samples from both the modern and last glacial maximum lgm synoptic levels from 178 sample locations yielding a total of 356 samples distributed throughout the atlantic ocean to determine the relative contribution of the iron oxides we factor analyzed the modern and lgm levels as a single data set the iron oxide factor explains about 25 of the variance in the combined core top and lgm data set mapped factor scores for the lgm and modern ocean indicate high iron oxide values are present in just two regions one off eastern north america and the other off northwest africa in the region off eastern north america iron oxide occurs primarily during the lgm as the previously noted brick red lutite a unique sediment type derived from the erosion of permo carboniferous red beds in atlantic canada a larger lobe shaped area of iron oxide rich sediment is present off northwest africa in both the modern and lgm levels the modern iron oxide lobe is coincident with the distribution of eolian dust as determined by observations from ships satellites and analysis of air samples during the lgm iron oxides exhibit a similar distribution except the southern margin of the region shifts equatorward and iron oxide concentration increases

radon and rilt anomalies detected before the irpinia south italy earthquake of november 23 1980 at great distances from the epicenter some investigators of istitute of physics and istitute of geology of the university of rome are carrying out measurements of tilt and groundwater radon content in sites located in central italy beginning from june to november 1980 anomalous variations in the radon content have been detected in rome and rieti sites water samples for discrete measurements of radon content were drawn periodically from underground strata the amplitude of the anomalies were 25 and 170 compared with the background level from about march 15 a bubble type tiltmeter installed at l aquila site showed a first anomalous tilting with a time scale of about two mounths and an amplitude of 15 rad a second anomalous tilting about 20 rad in amplitude was observed from the middle of may to november the seismicity m 4 0 4 7 within about 100 km of the sites seems to justify only the first anomalous tilting on november 23 1980 a strong m 6 5 earthquake took place in irpinia southern italy at about 250 km from rome rieti and l aquila sites we suggest to assume both the radon content anomalies and the second anomalous tilting as precursors of the irpinia earthquake

relation between hydrogen emission and seismic activities measurements of chemical composition of bubbles from a mineral spring at yuya spa situated close to the median tectonic line the longest active fault in japan showed that the periods of increased h2 emission coincided with occurrences of the ohno earthquake swarm nearby four cases of the coincidence without exception were observed in the last three years the fluctuation of h2 concentration ranges between 0 5 and 200 ppm whereas other gases such as he ar n2 and ch4 do not fluctuate much the h2 concentration is correlated with the energy released by the seismic activity this field evidence together with the results of laboratory experiments conducted bysugisakiet al 1983 leads to the conclusion that h2 observed at the mineral spring was produced by the reaction between groundwater and rock fractured in the seismic activities the observation that h2 in the mineral spring tends to appear prior to an earthquake suggests that microcracks may occur in rocks prior to earthquakes the precursory emission of h2 may be useful for earthquake prediction

weathering and pedogenesis in the sila grande massif calabria south italy from field scale to micromorphology abstract weathering and soil features in the upland landscapes developed on granitic terrains of the sila grande massif calabria south italy have been studied in this work the attempt to link field scale and micromorphological observations in order to better understand the main weathering processes and their controlling factors is revealed to be very powerful six soil profiles in the area around the cecita lake representative of different geomorphological units were characterised by field work optical microscopy and sem eds analysis a strong influence on weathering and pedogenesis by micro scale features of primary minerals and parent rock fabrics is shown key roles are played also by relief in the development and preservation or stripping of regolith soil mantles in relation to natural and man induced phenomena by time controlling rates and degree of development of the main weathering features by climate in terms of type and intensity of dominant processes

soil development in a quaternary fluvio lacustrine paleosol sequence in southern italy abstract the aim of this paper is to enrich our knowledge of an important paleosol succession located in bojano basin of the southern apennines italy with new pedological geochemical and magnetic data the studied area consists of alluvial and fluvial lacustrine sequences 160 m dating from the middle pleistocene 0 5 ma the study area shows the presence of recent soil consisting of well developed andosols rs and several clastic sedimentary levels alternating with four layers solum i ii iii and iv of paleosols soil and paleosols were analyzed by laser grain size distribution gsd diffuse reflectance spectroscopy drs trace elements and magnetic properties in order to evaluate the relative contributions of pedogenic and detrital components results showed that the finest pedogenic ferrimagnetic grains exhibit two trends with respect to the degree of pedogenesis indicate two different pedoclimate formations the paleosol sequence consists of highly weathered vertisols solum i and iv and of less weathered entisols solum ii iii the recent soil andosol has a strong bimodal distribution formed mostly by coarse silt size particles related to the volcanic parent material solum i showed a sharp unimodal clay gsd while solum iii and iv were composed of bimodal gsd with high percentages of fine silt size particles on the basis of the trace element content and gt fd ratio all solum i ii iii iv exhibited low weathering pedogenesis compared with rs and negligible contribution to the magnetic properties of the coarse fractions this occurs in vertisols which developed under humid temperate climates solum i and siv and formed below the layer of neapolitan yellow tuff developed after 12 15 ka bp in solum ii iii the finest sedimentary levels the low rate of pedogenesis could have developed under more cold climatic conditions after the last eruption campanian ignimbrite 39 ka in the late pleistocene

pedogenic development of volcanic ash soils along a climosequence in northern taiwan abstract andisols have been shown to evolve over time to other more weathered soil types however more information is needed on the time scales over which these changes occur under different climatic conditions in this study we analyze mineral weathering and soil formation along a soil climosequence formed on volcanic deposits of 400 ka of age in the subtropical climate of northern taiwan we sampled 6 pedons at elevations between 140 and 1090 m above sea level asl representing a climatic gradient from about 22 c mean annual temperature mat and 2000 mm mean annual precipitation map to about 16 5 c mat and 5000 mm map our results show that phosphate retention al o 1 2fe o si o and the fe o fe d ratio significantly increased with elevation the high elevation soils 900 m asl contained metastable poorly crystalline materials e g allophane ferrihydrite and classified as andisols whereas the low elevation soils

short term geomorphic analysis in a disturbed fluvial environment by fusion of lidar colour bathymetry and dgps surveys abstract objective estimating river s underwater bed elevations is a necessary but challenging task the objective of this study is to develop a revised approach to generate accurate and detailed digital terrain models dtms of a river reach by merging lidar data for the dry area with water depth indirectly derived from aerial imagery for wet areas methods this approach was applied along three sub reaches of the brenta river italy before and after two major flood events a regression model relating water depth and intensity of the three colour bands derived from aerial photos was implemented more than 2400 in channel depth calibration points were taken using a differential global positioning system dgps along a wide range of underwater bed forms results the resulting dtms closely matched the field surveyed bed surface and allowed to assess that a 10 year recurrence interval flood generated a predominance of erosion processes erosion dominated in the upper part of the study segment 104 082 m3 whereas a near equilibrium is featured on the lower reach 45 232 m3 the dtms allowed the detection of processes such as riffle pool downstream migration and the progressive scour of a pool located near a rip rap conclusion the presented approach provides an adequate topographical description of the river bed to explore channel adjustments due to flood events practice combining colour bathymetry and dgps surveys proved to represent a useful tool for many fluvial engineering ecology and management purposes implications the proposed approach represents a valuable tool for river topography description river management ecology and restoration purposes when bathymetric data are not available

relationship of the 1979 southern california radon anomaly to a possible regional strain event during the second half of 1979 anomalously high emanation of radon was recorded at two stations of the automated radon thoron monitoring network operated by the w k kellogg radiation laboratory of the california institute of technology the two stations exhibiting major anomalies kresge and dalton canyon are located approximately 30 km apart on the frontal fault system of the transverse ranges of southern california at kresge the anomaly began on june 21 1979 and continued through december 1979 at dalton canyon the anomaly started about 3 weeks later and also continued through december 1979 at both sites the anomalous levels of radon decreased but did not return entirely to normal values shortly before october 15 1979 during the week of october 15 1979 a 6 6 m earthquake occurred about 290 km to the southeast of the two stations and later in that week earthquakes of magnitude 4 2 and 4 1 occurred at malibu and lytle creek the latter two events were within 60 km of the monitors a radon thoron monitor at lytle creek recorded no long term anomaly but did record a sharp spikelike decrease in the radon level on october 13 1979 coincident with our observations of anomalous radon levels other investigators have reported anomalies or suspected anomalies in several other geodetic geophysical and geochemical signals from the same general region the rapid temporal development of several of the anomalies together with the large area over which they were observed suggests that a large scale strain event took place which may have been responsible both for the widespread anomalies and for the seismicity that occurred in the region subsequent to the onset of the anomalies

photogrammetric monitoring of small streams under a riparian forest canopy the recent advent of digital photogrammetry has enabled the modeling and monitoring of river beds at relatively high spatial resolution 0 01 to 1 m through the extraction of digital elevation models dems the traditional approach to image capture has been to mount a metric camera to an aircraft although non metric cameras have been mounted to a variety of novel aerial platforms to acquire river based imagery e g helicopters radio controlled motorized vehicles tethered blimps and balloons however most of these techniques are designed to acquire imagery at flying heights above the riparian tree canopy in relatively narrow channels e g 20 m bankfull width streamside trees can obscure the channel and limit continuous photogrammetric data acquisition of both the channel bed and banks while still providing useful information regarding the riparian canopy and even spot elevations of the channel this paper presents a technique for the capture and analysis of close range photogrammetric data acquired from a vertically mounted non metric camera suspended 10 m above the channel bed by a unipod the camera is positioned under the riparian forest canopy so that the channel bed can be imaged without obstruction the system is portable and permits relatively rapid image acquisition over rough terrain and in dense forest the platform was used to generate dems with a nominal ground resolution of 0 03 m dems generated from this platform required post possessing to either adjust or eliminate erroneous cells introduced by the extraction process overhanging branches and by the effects of refraction at the air water interface for submerged portions of the channel bed the vertical precision in the post processed surface generally ranged from 0 01 to 0 1 m depending on the quality of triangulation and the characteristics of the surface being imaged copyright 2010 john wiley sons ltd

geochemical monitoring of geothermal waters 2002 2004 along the north anatolian fault zone turkey spatial and temporal variations and relationship to seismic activity a total of nine geothermal fields located along an 800 km long e w transect of the north anatolian fault zone nafz turkey were monitored for three years 2002 2004 inclusive 3 sampling periods per year to investigate any possible relationship between seismic activity and temporal variations in the chemistry and isotope characteristics of waters in the fields the geothermal fields monitored in the study were from west to east yalova efteni bolu mudurnu seben kursunlu cankiri hamamozu gozlek and resadiye the chemical major anion cation contents and isotopic 18o 16o d h 3h compositions of hot and cold waters of the geothermal sites were determined in order to both characterize the chemical nature of the individual fields and identify possible temporal variations associated with localized seismic activity the geothermal waters associated with the nafz are dominantly na hco3 whereas the cold waters are of the ca hco3 type the oxygen and hydrogen isotope compositions reveal that the hot waters are meteoric in origin as are their cold water counterparts however the lower 18o d and 3h contents of the hot waters point to the fact that they are older than the cold waters and that their host aquifers are recharged from higher altitudes with virtually no input from recent post bomb precipitation although no major earthquakes e g with m 5 were recorded along the nafz during the course of the monitoring period variations in the chemical and isotopic compositions of some waters were observed indeed the timing of the chemical isotopic changes seems to correlate with the occurrence of seismic activity of moderate magnitude 3 m 5 close to the sampling sites in this respect cl 3h and ca seem to be the most sensitive tracers of seismically induced crustal perturbations and the yalova and efteni fields appear to be the key localities where the effects of seismic activity on the geothermal fluids are most pronounced over the monitoring period the present study has produced a baseline database for future studies directed at characterizing the effects of moderate major earthquakes on the composition of geothermal waters along the nafz future work involving longer monitoring periods with more frequent sampling intervals should lead to a better understanding of the underlying mechanism s producing the observed chemical and isotopic variations

the measurement of river bank erosion and lateral channel change a review a detailed review and chronological survey is presented of the various techniques which have been used for the measurement of river bank erosion and channel change the techniques are classified according to the time scales involved long intermediate and short and each is discussed with respect to accuracy and repeatability the methods covered include sedimentological evidence botanical evidence historical sources planimetric resurvey repeated cross profiling erosion pins and terrestrial photogrammetry prospects for future developments are also discussed

radon anomalies in soil gas and groundwater as earthquake precursor phenomena abstract earthquake related changes in soil gas and groundwater radon have been detected at a sensitive observation site in the kangra valley himachal pradesh india using both instantaneous and time integrated techniques the recording station at palampur in the kangra valley is located near the main boundary fault of the himalayas eleven earthquake related anomalies have been recorded since august 1989 in both the soil gas and in the groundwater simultaneously in order to differentiate the real signal from noise the effect of meteorological variables soil and air temperature rainfall pressure humidity and wind velocity on radon emanation was also studied most of the radon anomalies are found to be correlated with earthquakes rather than to changes in meteorological conditions

andisols of madeira island portugal characteristics and classification abstract this paper reports the morphological physical chemical and mineralogical features of seven pedons selected to represent the major types of udands occurring in madeira island all of these pedons showed similar high contents of organic matter 60 g kg 1 of c and often more to depths of more than 40 cm despite this similarity only three pedons had the colour requirements of fulvudands the others had colour values too high to meet the criterion this was attributed to the high amounts of hematite masking the dark brown colour of organic colloids as testified by their variable total reserve in bases trb and their variable contents of allophane andisols of madeira have reached different stages of weathering the most weathered ones are very acid alic and very rich in total fe 2 o 3 they qualify as non allophanic andisols it is suggested that the pyroclastic parent materials of these highly weathered andisols had been altered prior to the present pedogenetic cycle such a hypothesis would explain their mineralogy characterized by high lithogenic hematite and low weatherable minerals contents in such non allophanic andisols the andic soil properties are probably due mainly to al humus complexes accompanied by some ferrihydrite

association of subsurface radon changes in alaska and the northeastern united states with earthquakes abstract changes of radon concentration in the ground have been reported to correlate with seismic activity in many places over widely varying distances from the earthquake epicenters sometimes over 100 s and occasionally over 1000 s of km depending on the magnitude m of the earthquakes for proper use of such correlations in forecasting the location and size of impending earthquakes it would be useful to establish a relation between m and the maximum distance x m at which radon can be significantly altered by preseismic effects we have monitored radon in the ground continuously at blue mountain lake ny starting dec 3 1975 and at three locations in alaska icy bay yakataga and sand point starting nov 12 1979 march 5 1980 and june 29 1980 respectively sample correlations from visual examination of the recent radon record and tentative use of a proposed scaling relation show a number of possible earthquake related signals at these locations the data are compatible with scaling relations that were derived from two separate models of premonitory elastic strains in this work x m 10 0 48 m where x m is in units of km and m 3 since tilt and strain signals correlate similarly with magnitude and distance it is likely that most earthquake related radon signals are mechanically induced

the production of digital elevation models for experimental model landscapes automated digital photogrammetry was used to produce digital elevation models of experimental model landscapes under controlled laboratory conditions as part of a series of rainfall erosion experiments looking at the evolution of landforms in response to erosion the method allowed the elevations of the experimental landscapes to be studied in great detail on a regular grid digital terrain map with relatively very little effort digital photogrammetry produced elevation data at a resolution of 6 mm with a standard deviation of 2 0 mm over an experimental catchment relief of approximately 200 mm this resolution is considerably better than that achievable by conventional manual photogrammetry the density of grid points was sufficiently high that small scale details such as knickpoints developing in channels were represented the method can facilitate the study of both experimental and natural landscapes in great detail copyright 2001 john wiley sons ltd

geochemical modeling approach to predicting arsenic concentrations in a mine pit lake abstract between 1968 and 1983 the north pit at the getchell mine humboldt county nv filled with water to form a lake in 1983 water quality data were collected with the following results as concentrations of 0 29 to 0 59 mg l ph of 7 1 to 7 9 so 4 concentrations of 1490 to 1640 mg l and tds of 2394 to 2500 mg l using geochemical modeling techniques presented here pit lake waters have been theoretically allowed to react for 8 5 a the approximate time that the north pit had been completely full by 1983 modeling results predict ph of 7 9 to 8 2 so 4 concentrations of 1503 to 1644 mg l tds of 2054 to 2366 mg l and as concentrations ranging from 0 57 in the hypolimnion to 96 mg l in the epilimnion in the epilimnion model results do not match observed as concentrations suggesting that mechanisms such as precipitation of arsenate salts or adsorption to mineral surfaces may control as levels in an actual pit lake system adsorption to fe oxyhydroxide surfaces is questioned by the authors because of the low fe content in the getchell system but adsorption to al oh 3 gibbsite and clay mineral surfaces may be important in controlling natural as concentrations