freshwater control of ice rafted debris in the last glacial period at mono lake california usa abstract the type section silts of the late pleistocene wilson creek formation at mono lake contain outsized clasts dominantly well rounded pebbles and cobbles of sierran lithologies lithic grains 425 m show a similar pattern of variability as the 10 mm clasts visible in the type section with decreasing absolute abundance in southern and eastern outcrops the largest concentrations of ice rafted debris ird occur at 67 57 ka and 46 32 ka with strong millennial scale variability while little ird is found during the last glacial maximum and deglaciation stratigraphic evidence for high lake level during high ird intervals and a lack of geomorphic evidence for coincidence of lake and glaciers strongly suggests that rafting was by shore ice rather than icebergs correspondence of carbonate flux and ird implies that both were mainly controlled by freshwater input rather than disparate non climatic controls conversely the lack of ird during the last glacial maximum and deglacial highstands may relate to secondary controls such as perennial ice cover or sediment supply high ird at mono lake corresponds to low glacial flour flux in owens lake both correlative to high warm season insolation high resolution extra basinal correlation of the millennial peaks awaits greatly improved age models for both records

the 2004 sumatra tsunami in the southeastern pacific ocean new global insight from observations and modeling the 2004 sumatra tsunami was an unprecedented global disaster measured throughout the world oceans the present study focused on a region of the southeastern pacific ocean where the westward circumferentially propagating tsunami branch converged with the eastward branch based on data from fortuitously placed chilean dart 32401 and tide gauges along the coast of south america by comparison of the tsunami and background spectra we suppressed the influence of topography and reconstructed coastal spectral ratios that were in close agreement with a ratio at dart 32401 and spectral ratios in other oceans findings indicate that even remote tsunami records carry spectral source signatures birth marks the 2004 tsunami waves were found to occupy the broad frequency band of 0 25 10 cph with the prominent ratio peak at period of 40 min related to the southern fast slip source domain this rupture hot spot of 350 km was responsible for the global impact of the 2004 tsunami data from dart 32401 provided validation of model results the simulated maximum tsunami wave height of 2 25 cm was a conservative approximation to the measured height of 2 05 cm the computed tsunami travel time of 25 h 35 min to dart 32401 although 20 min earlier than the actual travel time provided a favorable result in comparison with 24 h 25 min estimated from classical kinematic theory the numerical simulations consistently reproduced the wave height changes observed along the coast of south america including local amplification of tsunami waves at the northern stations of arica 72 cm and callao 67 cm

the 2009 samoan and 2010 chilean tsunamis recorded on the pacific coast of russia two remote tsunamis were recorded on the pacific coast of russia a relatively weak samoan tsunami of september 29 2009 and a much stronger chilean tsunami of february 28 2010 in the area of the south kuril islands records were obtained using autonomous bottom pressure gauges of the institute of marine geology and geophysics imgg additionally for the oceanic coast of the kamchatka peninsula paramushir and bering islands we used data transmitted from coastal tide gauges of the russian tsunami warning service tws the maximum trough to crest heights of the samoan tsunami were about 30 40 cm and were recorded about 3 h after the first tsunami arrival the maximum chilean tsunami trough to crest wave heights were 218 cm at severo kurilsk 187 cm at tserkovnaya bay shikotan island and 140 cm at khodutka bay kamchatka peninsula the time between first and maximum waves reached 4 h strong sea level oscillations for both events range for a long time about 15 17 h the samoan tsunami induced high frequency oscillations a considerable increase in spectral energy in the tsunami spectrum was observed at periods of 4 20 min in contrast the chilean tsunami induced low frequency oscillations the dominant periods were 30 80 min a probable reason for these differences is the different extensions of the source areas the chilean source was much larger than the samoan source and the different energy radiation directions from the sources local topography resonant effects were the main reason of well expressed peaks in power spectra in different areas with a period of 10 min khodutka bay 19 20 min malokurilskaya and tserkovnaya bays 29 min krabovaya inlet and 43 min avachinskaya guba and nikolskoe

the el salvador and philippines tsunamis of august 2012 insights from sea level data analysis and numerical modeling we studied two tsunamis from 2012 one generated by the el salvador earthquake of 27 august mw 7 3 and the other generated by the philippines earthquake of 31 august mw 7 6 using sea level data analysis and numerical modeling for the el salvador tsunami the largest wave height was observed in baltra galapagos islands 71 1 cm located about 1 400 km away from the source the tsunami governing periods were around 9 and 19 min numerical modeling indicated that most of the tsunami energy was directed towards the galapagos islands explaining the relatively large wave height there for the philippines tsunami the maximum wave height of 30 5 cm was observed at kushimoto in japan located about 2 700 km away from the source the tsunami governing periods were around 8 12 and 29 min numerical modeling showed that a significant part of the far field tsunami energy was directed towards the southern coast of japan fourier and wavelet analyses as well as numerical modeling suggested that the dominant period of the first wave at stations normal to the fault strike is related to the fault width while the period of the first wave at stations in the direction of fault strike is representative of the fault length

some tsunami characteristics deducible from tide records abstract after an initial 40 hour diffusion period the time decay of tsunami variance was found to be uniformly exponents for 28 events among eight pacific tide stations thew results essentially confirm munk s acoustic deny hypothesis except that the decay e folding time 22 h more nearly equated the ocean s normal mode transit time 21 h than munk s mean collision time 14 h relative tsunami energy obtained by extrapolating exponential decay back to t 0 was found to be similarly ranked among tsunamis at all stations and roughly proportional to seismic energy a total energy estimate for the tsunami of 9 march 1957 obtained by correcting the observed energy decay at wake island for instrument and island response provided normalized total energy estimates for all tsunamis that were consistent with independent estimates by kajiura and by aida similarities between power spectra computed from these time series suggests that station response is primarily linear normal mode forcing of the conti

the dual source region for the 2004 sumatra tsunami 1 wave arrival times obtained from coastal tide gage and satellite altimetry records for the indian ocean are used to delineate the source region for the december 26 2004 sumatra tsunami findings define a curved 250 km wide 1000 km long tsunami source region centered over the sunda subduction zone which closely matches the seismic source estimated from broadband geophysical data imbedded in this general region are hot spots associated with the southern fast slip and northern slow slip domains which served as distinct source areas for the destructive waves that inundated the coast of the indian ocean

source estimate and tsunami forecast from far field deep ocean tsunami waveforms the 27 february 2010 mw 8 8 maule earthquake we inverted the 2010 maule earthquake tsunami waveforms recorded at dart deep ocean assessment and reporting tsunamis stations in the pacific ocean by taking into account the effects of the seawater compressibility elasticity of the solid earth and gravitational potential change these effects slow down the tsunami speed and consequently move the slip offshore or updip direction consistent with the slip distribution obtained by a joint inversion of dart tide gauge gps and coastal geodetic data separate inversions of only near field dart data and only far field dart data produce similar slip distributions the former demonstrates that accurate tsunami arrival times and waveforms of trans pacific tsunamis can be forecast in real time the latter indicates that if the tsunami source area is as large as the 2010 maule earthquake the tsunami source can be accurately estimated from the far field deep ocean tsunami records without near field data

europium mass balance in polymict samples and implications for plutonic rocks of the lunar crust abstract from correlations of sm concentration and sm eu ratio with th concentration for a large number of polymict samples from various locations in the lunar highlands and the value of 0 91 g g for the mean th concentration of the highlands surface crust obtained by the orbiting gamma ray experiments we estimate the mean concentrations of sm and eu in the lunar surface crust to be between 2 and 3 g g sm and 0 7 and 1 2 g g eu the compositional trends indicate that there is no significant enrichment or depletion of eu on the average compared to sm relative to chondritic abundances i e there is no significant eu anomaly in average upper crust although rich in plagioclase 70 the upper crust does not offer evidence for a gross vertical separation of plagioclase from the final liquid from which it crystallized this and the chondritic ratio of eu al in average highlands material imply that the net effect of the processes that led to formation of the lunar crust was to put most of the al and incompatible elements in the crust the concentration of eu in most polymict samples from the highlands exceeds that which can be supplied by the fraction of kreep necessary to supply the incompatible trace elements plus the fraction of plagioclase necessary to supply the al if the plagioclase has the composition of that in ferroan anorthosite among plutonic rocks only plagioclase in rocks from the magnesian suite can supply the excess eu in the polymict rocks owing to the intermediate value of the mean mg fe ratio of the crust a significant fraction of the mafic rocks of the lunar highlands must have lower mg fe ratios than the norites and troctolites of the magnesian suite of plutonic rocks a large fraction of the plagioclase in the lunar crust is associated not with ferroan anorthosite but with more mafic rocks e g norite anorthositic norite there is little evidence in the eu data that the lunar crust ever consisted of a thick shell of nearly pure plagioclase as envisioned in some formulations of the magma ocean model of its formation

rare earth element concentrations and speciation in alkaline lakes from the western u s a the rare earth element ree concentrations of lake water from five alkaline lakes i e mono walker abert summer and goose lakes within the great basin of the western u s a are reported all of the lakes exhibit hree enriched shale normalized patterns the speciation of the rees was determined and in all cases species greater than 99 of each of the rees exist as ln co3 2 complexes the only exception to this is summer lake where minor amounts of phosphate species were also predicted the large enrichments in the hrees observed in these lakes are the result of the formation of stable carbonate complexes in solution where the hrees preferentially form stronger carbonate complexes than the lrees activity product calculations for ree phosphate coprecipitates in these lakes indicate the lakes are close to saturation with respect to these phases and suggest that these precipitates may limit the maximum dissolved ree concentrations in the lakes

effect of variable bathymetry on the amplitude of teleseismic tsunamis a ray tracing experiment we apply surface wave ray tracing techniques to tsunami propagation in an ocean of variable depth because tsunami velocities are proportional to the square root of the depth of the water column the juxtaposition of oceanic plateaux and basins generates strong lateral velocity gradients and bathymetric features can act as lenses focusing or defocusing the tsunami waves we present a reconstruction of the tsunami wave field from the great chilean earthquake of 1960 an order of magnitude computation based on the concept of ray density provides qualitative agreement with observations at several sites in the pacific ocean we also demonstrate the possibility of using reciprocal maps to identify tsunamigenic zones that present particular danger for a given receiving shore

tide gauge observations of the indian ocean tsunami december 26 2004 the magnitude 9 0 earthquake centered off the west coast of northern sumatra 3 307 n 95 947 e on december 26 2004 at 00 59 utc united states geological survey usgs 2005 usgs earthquake hazards program latest earthquakes earthquake hazards program http earthquake usgs gov eqinthenews 2004 usslav 2005 generated a series of tsunami waves that devastated coastal areas throughout the indian ocean tide gauges operated on behalf of national and international organizations recorded the wave form at a number of island and continental locations this report summarizes the tide gauge observations of the tsunami in the indian ocean available as of january 2005 and provides a recommendation for the use of the basin wide tide gauge network for future warnings

the evolution of deep ocean pressure measurements in the uk abstract this paper is a brief review of the work carried out by the proudman oceanographic laboratory pol in measuring tides and sub surface pressure variations in the deep water of the ocean basins using bottom pressure recorders bprs it deals particularly with the work of david cartwright which he began in the early 1970s and carried out until he left pol in 1986 but is continued by his co workers of that time the paper mentions the early work in the north atlantic when instrument deployments were limited to one month duration and describes what was achieved from the measurements it concentrates mainly on measurements that were made since the early 1980s when it became possible because of developments in instrument technology to achieve individual measurements lasting for one year or more the results obtained from these measurements are described and some interesting features of the spectrum of the pelagic sub surface pressure are discussed as instrument technology further improved it became possible to study low frequency variations in sub surface pressure the contributions made by pol to studies of the atlantic and indian oceans and the contribution to ocean circulation studies during the world ocean circulation experiment are discussed this led to the development of an instrument capable of operating continuously at ocean depths for five years the preliminary results from a four year deployment of this instrument which was completed in november 1996 are included

petrology chemistry and origin of apollo 15 regolith breccias abstract variations in modal petrology mineral compositions and bulk compositions were determined for ten apollo 15 regolith breccias for comparison with local soils and assessment of the intrasite petrologic variability of the apollo 15 regolith based on the above criteria the breccias are of local origin and mimic the soils from the corresponding sampling stations with the exception of station 2 breccia 15205 this sample formed from an anomalous regolith and although not considered exotic to the site is not representative of the soil at the site kreep basalt and green glass components vary from trace amounts to dominant in the breccias evidence that these materials entered the regolith prior to formation of the breccias breccias from the edge of hadley rille are modally richer in highland fragments than the soils whereas at the base of hadley delta the reverse is true this is explained by the loss of material into the rille to be replaced by basalt derived material making the soils more basalt rich at the base of hadley delta highland material is accumulating and the soils are becoming more highland rich over billions of years these processes have developed differences between the present day evolving soils and fossil non evolving soils represented by the regolith breccias this shows that there has been little change in the geology and the morphology of the apollo 15 site probably since the eruption of mare basalts at the site 3 3 b y

new 230th u and 14c ages from lake lahontan carbonates nevada usa and a discussion of the origin of initial thorium five sets of coeval lacustrine carbonate samples from pleistocene lake lahontan in western nevada were dated by both the ams 14c and 230th u isochron methods all five groups of samples were analyzed for u th isotopes by alpha spectrometry and one of the groups was additionally measured by thermal and secondary ionization mass spectrometry tims and sims for comparison the 14c ages were corrected to calendar years using the calibration curve recommended by bard et al 1992 without local reservoir correction on the 14c ages mean 230th u isochron ages of some sets are apparently older than their calendar corrected 14c ages by up to 2300 years modern carbon contamination of these carbonate samples through recrystallization or deposition of secondary calcite is likely to be responsible for part of the age discrepancies we explored additional biases associated with the isochron ages maybe produced by the presence of initial th coprecipitated from the lake water it can be shown that if dissolved hydrogenous th is directly incorporated into the pure carbonates then the three component mixing among 1 detrital th 2 hydrogenous th adsorbed on detritus and 3 hydrogenous th incorporated by the carbonate can introduce a positive age bias we have developed an approach to estimate the magnitude of this bias of the lake lahontan carbonates the preliminary estimates suggest a positive age bias of 1000 to 2000 years for two sets of the samples

assessing li and other leachable geochemical proxies for paleo salinity in lake sediments from the mono basin ca usa abstract regional climate driven hydrological changes are accompanied by salinity changes in closed basin lakes we have investigated acid leachable li along with other leachable ions including mg ca and sr as geochemical proxies of salinity in lake sediments in the mono basin california all the elements in the acid leachable suite show a strong correlation with paleo lake level estimates based on physical and stratigraphic evidence the caco3 content of lake sediments which has been shown to be a reliable proxy for lake level changes in the mono basin and the adjoining owens lake basin corresponds well with our acid leachable proxy data

the lunar regolith chemistry mineralogy and petrology the lunar regolith a several meter thick layer of unconsolidated debris forms the interface between the moon and its space environment the regolith forms from lithic sources by the destructional processes of comminution and the constructional processes of agglutinate formation in this manner a steady state soil can develop and will remain in a type of dynamic equilibrium until the system is disturbed by burial or mixing with new soil mixing takes place mainly on a local scale vertically through meters and horizontally over several kilometers lateral transport is a relatively inefficient process and therefore most of the lunar soil components were derived locally there is no evidence for preferential transport of the finer soil fractions relative to the coarser fractions the truly exotic derived at distances of tens of kilometers component is generally in low abundance 1 therefore remotely sensed data should provide a reasonably accurate picture of bedrock geology the chemical composition of the regolith varies with grain size the 10 m fraction is chemically fractionated from the bulk soil in most cases the 10 m fraction is enriched in al2o3 cao na2o k2o light rare earth elements and th and depleted in mgo feo mno and sc these systematics are largely a result of simple comminution with feldspar and friable mesostasis from local source rocks concentrating in the finest fraction there is evidence that agglutinate glass forms preferentially by fusion of the finest soil fractions therefore agglutinate glass like the 10 m soil fraction appears to be fractionated from bulk soil compositions highland soils are distinct from mare soils both chemically and petrologically soil samples collected near mare highland contacts are mixtures of the two lithologies mineral chemical systematics of monomineralic fragments in the lunar soil provide important clues to soil provenance they can in some cases sort out the highland mare contributions and in special cases can even further pinpoint a lithic source in theory lunar regolith cores can serve as solar probes recording the sun s activity over billions of years in practice this has generally not been the case the formation and evolution of most cores is still poorly understood for most we have not established how they formed for example how many depositional and erosional events were involved what the time span involved in the accretion of the sampled soil column was and how long that soil column has remained in situ without this information it is difficult if not impossible to read the sun s record more interdisciplinary studies on cores must be carried out before they can be used as solar probes

understanding the lunar surface and space moon interactions the surface of the moon is a critical boundary that shapes our understanding of the moon as a whole all geologic mapping and remote sensing techniques utilize only the outermost portion of the moon before leaving the moon for study in our laboratories all lunar samples that have been studied existed at or very near the surface with the exception of the deeply probing geophysical techniques our understanding of the interior of the moon is derived from surficial but not superficial information coupled with boundary of the lunar crust it is the lower boundary layer of the tenuous lunar atmosphere and constitutes both a source and a sink for atmospheric gases the surface is also where the moon interacts with the space environment causing changes in the physical nature of lunar materials and provides a laboratory for the study of processes that occur on all airless bodies the data obtained remotely by the galileo clementine and lunar prospector missions as well as data derived from lunar meteorites have resulted in major changes to our understanding of global distributions of chemistry and rocks this chapter summarizes the current understanding of this critical interface the surface of the moon in its role as the lower boundary of the lunar atmosphere the upper boundary of the crust and the window through which we view through remote sensing the composition of the crust and the history of the moon in this post lunar prospector time the view of the moon has changed lending new perspectives to lunar samples and lunar processes but the new view will likely remain in flux as we continue to digest the results from these recent space missions and move forward to a new era of lunar exploration despite the freshness of our perspective this is an important moment to capture

estimate of tsunami source using optimized unit sources and including dispersion effects during tsunami propagation the 2012 haida gwaii earthquake we apply a genetic algorithm ga to find the optimized unit sources using dispersive tsunami synthetics to estimate the tsunami source of the 2012 haida gwaii earthquake the optimal number and distribution of unit sources gives the sea surface elevation similar to that from our previous slip distribution on a fault using tsunami data but different from that using seismic data the difference is possibly due to submarine mass failure in the source region dispersion effects during tsunami propagation reduce the maximum amplitudes by up to 20 of conventional linear long wave propagation model dispersion effects also increase tsunami travel time by approximately 1 min per 1 300 km on average the dispersion effects on amplitudes depend on the azimuth from the tsunami source reflecting the directivity of tsunami source while the effects on travel times depend only on the distance from the source

fault slip distribution of the 2014 iquique chile earthquake estimated from ocean wide tsunami waveforms and gps data we applied a new method to compute tsunami green s functions for slip inversion of the 1 april 2014 iquique earthquake using both near field and far field tsunami waveforms inclusion of the effects of the elastic loading of seafloor compressibility of seawater and the geopotential variation in the computed green s functions reproduced the tsunami traveltime delay relative to long wave simulation and allowed us to use far field records in tsunami waveform inversion multiple time window inversion was applied to tsunami waveforms iteratively until the result resembles the stable moment rate function from teleseismic inversion we also used gps data for a joint inversion of tsunami waveforms and coseismic crustal deformation the major slip region with a size of 100 km 40 km is located downdip the epicenter at depth 28 km regardless of assumed rupture velocities the total seismic moment estimated from the slip distribution is 1 24 1021 n m mw 8 0

darts and cork in cascadia basin high resolution observations of the 2004 sumatra tsunami in the northeast pacific 1 we report unique deep sea recordings of the sumatra tsunami of december 2004 by high resolution dart deep ocean assessment and reporting of tsunami and cork circulation obviation retrofit kit bottom pressure sensors deployed at depths of 1500 3500 m in cascadia basin in the northeast pacific the simultaneous records from these sites establish the first ever regional scale tsunami detection array for the open ocean enabling us to resolve both seafloor and crustal tsunami signals and to determine fundamental properties of the waves following their 22 000 km journey from the source region waves reaching the basin had mean amplitudes of 5 mm with energy spread over a broad frequency band from 0 4 to 7 cph peak tsunami energy was in the 0 8 to 2 cph 75 to 30 min band leading waves from the event arrived 34 35 h after the earthquake roughly 7 h later than expected suggesting that the tsunami mainly propagated by the most economic minimum energy loss path along mid ocean ridge wave guides rather than taking the direct and fastest path across the ocean motions within the peak energy band comprise roughly 50 coherent progressive waves propagating from the south at longwave phase speeds of 150 ms 1 and 50 random waves scattered from the coast and bottom irregularities tsunami amplitudes in the borehole were one third those on the seafloor the extensive ringing and anomalously slow 3 5 day e folding decay time of the tsunami wave energy indicates long duration energy flux radiating from the indian ocean via the southern pacific ocean

odessa tsunami of 27 june 2014 observations and numerical modelling on 27 june a 1 2 m high wave struck the beaches of odessa the third largest ukrainian city and the neighbouring port town illichevsk northwestern black sea throughout the day prominent seiche oscillations were observed in several other ports of the black sea tsunamigenic synoptic conditions were found over the black sea stretching from romania in the west to the crimean peninsula in the east intense air pressure disturbances and convective thunderstorm clouds were associated with these conditions right at the time of the event a 1 5 hpa air pressure jump was recorded at odessa and a few hours earlier in romania we have utilized a barotropic ocean numerical model to test two hypotheses 1 a tsunami like wave was generated by an air pressure disturbance propagating directly over odessa experiment 1 2 a tsunami like wave was generated by an air pressure disturbance propagating offshore approximately 200 km to the south of odessa and along the shelf break experiment 2 both experiments decisively confirm the meteorological origin of the tsunami like waves on the coast of odessa and imply that intensified long ocean waves in this region were generated via the proudman resonance mechanism while propagating over the northwestern black sea shelf the odessa tsunami of 27 june 2014 was identified as a beach meteotsunami similar to events regularly observed on the beaches of florida usa but different from the harbour meteotsunamis which occurred 1 3 days earlier in ciutadella baleares spain mazara del vallo sicily italy and vela luka croatia in the mediterranean sea despite that they were associated with the same atmospheric system moving over the mediterranean black sea region on 23 27 june 2014

wisconsin glaciation of the sierra nevada 79 000 15 000 yr b p as recorded by rock flour in sediments of owens lake california chemical analyses of the clay sized fractions of 564 continuous sediment samples 200 yr resolution from composite core ol90 92 allow quantification of an abundance of glacial rock flour rock flour produced during glacier advances is represented by clay sized plagioclase k feldspar and biotite in homogeneous internal composition the abundance of rock flour is deemed proportional to the intensity of glacies advances age control for the composite section is provided by combining previously published radiocarbon dates on organics u th dates on ostracode shells and u th dates on saline minerals from nearby searles lake correlated to ol92 by pollen the rock flour record displays three levels of variability 1 a dominant one of about 20 000 yr related to summer insolation and precipitation 2 an intermediate one of 3000 5000 yr perhaps related to north atlantic heinrich events and 3 a minor one of 1000 2000 yr perhaps related to north atlantic thermohaline driven air temperature variation

spectral analysis of tsunami waves separation of source and topography effects a new approach is proposed to separate the influence of source and topography in observed tsunami spectra and to reconstruct the initial source spectrum the method assumes a linear tide gauge response to external forcing and is based on comparative analysis of tsunami and background spectra evaluation of the ratio of tsunami to background spectra gives functional characteristics that are invariant of station location and dependent only on the source parameters three events the urup tsunami of december 22 1991 northwest pacific the hokkaido southwest okushiri tsunami of july 12 1993 sea of japan and the shikotan tsunami of october 4 1994 northwest pacific are used as examples of the proposed approach the source spectra reconstructed from the analysis of different tide gauges were found to be in good agreement with each other and with the seismological geodetic and field survey data

seismology speed and size of the sumatra earthquake we now have a clearer picture of the seismic features of last year s gigantic event our seismological results reveal that indonesia s devastating sumatra andaman earthquake on 26 december 2004 was 2 5 times larger than initial reports suggested second only to the 1960 chilean earthquake in recorded magnitude they indicate that it slowly released its energy by slip along a 1 200 km fault generating a long rupture that contributed to the subsequent tsunami now that the entire rupture zone has slipped the strain accumulated from the subduction of the indian plate beneath the burma microplate has been released and there is no immediate danger of a similar tsunami being generated on this part of the plate boundary although large earthquakes on segments to the south still present a threat

the tsunami phenomenon abstract with human activity increasingly concentrating on coasts tsunamis from japanese tsu harbour nami wave are a major natural hazard to today s society stimulated by disastrous tsunami impacts in recent years for instance in south east asia 2004 or in japan 2011 tsunami science has significantly flourished which has brought great advances in hazard assessment and mitigation plans based on tsunami research of the last decades this paper provides a thorough treatise on the tsunami phenomenon from a geoscientific point of view starting with the wave features tsunamis are introduced as long shallow water waves or wave trains crossing entire oceans without major energy loss at the coast tsunamis typically show wave shoaling funnelling and resonance effects as well as a significant run up and backflow tsunami waves are caused by a sudden displacement of the water column due to a number of various trigger mechanisms such are earthquakes as the main trigger submarine and subaerial mass wastings volcanic activity atmospheric disturbances meteotsunamis and cosmic impacts as is demonstrated by giving corresponding examples from the past tsunamis are known to have a significant sedimentary and geomorphological off and onshore response so called tsunamites form allochthonous high energy deposits that are left at the coast during tsunami landfall tsunami deposits show typical sedimentary features as basal erosional unconformities fining upward and landward a high content of marine fossils rip up clasts from underlying units and mud caps all reflecting the hydrodynamic processes during inundation the on and offshore behaviour of tsunamis and related sedimentary processes can be simulated using hydro and morphodynamic numerical models the paper provides an overview of the basic tsunami modelling techniques including discretisation guidelines for appropriate temporal and spatial resolution as well as the nesting method furthermore the boussinesq approximation a simplification of the three dimensional navier stokes equations is presented as a basic theory behind numerical tsunami models which adequately reflects the non linear dispersive wave behaviour of tsunamis the fully non linear boussinesq equations allow the simulation of tsunamis e g in the form of n waves based on the various subtopics presented recommendations for future multidisciplinary tsunami research are made it is especially discussed how the combination of sedimentary and geomorphological tsunami field traces and numerical modelling techniques can contribute to derive locally relevant tsunami sources and to improve the assessment of tsunami hazards considering the individual pre history and physiogeographical setting of a specific region

comparison of in situ bottom pressure data with grace gravimetry in the crozet kerguelen region two time series of deep ocean bottom pressure records bprs in between the crozet islands and kerguelen are compared with grace gravity recovery and climate experiment equivalent water heights an analysis of the correlation is performed for four time series 1 monthly averages of the equivalent water height at the crozet islands 2 the same near the kerguelen islands 3 the mean of the two preceding series and 4 the difference between the two locations expressed in terms of geostrophic transport we find that smoothed grace solutions are strongly correlated with the bpr data with correlation coefficients in the order of 0 7 0 8 consequently grace measures real oceanic mass variations in this region

energy decay of the 2004 sumatra tsunami in the world ocean the catastrophic indian ocean tsunami generated off the coast of sumatra on 26 december 2004 was recorded by a large number of tide gauges throughout the world ocean this study uses gauge records from 173 sites to examine the characteristics and energy decay of the tsunami waves from this event in the indian atlantic and pacific oceans findings reveal that the decay e folding time of the tsunami wave energy within a given oceanic basin is not uniform as previously reported but depends on the absorption characteristics of the shelf adjacent to the coastal observation site and the time for the waves to reach the site from the source region in general the decay times for island and open ocean bottom stations are found to be shorter than for coastal mainland stations decay times for the 2004 sumatra tsunami ranged from about 13 h for islands in the indian ocean to 40 45 h for mainland stations in the north pacific

the paleoclimatic interpretation of clay minerals in sediments a review abstract the application of paleoclimatic interpretation to clay minerals from continental and marine sediments is reviewed and the advantages of this method are indicated levels relatively rich in chlorite illite palygorskite and quartz are interpreted as corresponding to relatively dry periods while more humid periods lead to more intensive weathering and consequently to the dominance of clay minerals more advanced in the relative stability scale such as kaolinite smectite is taken to indicate a climate with contrasting seasons and a pronounced dry season using this and similar schemes the paleoclimates of areas adjoining the mediterranean basin north sea north atlantic southern arctic equatorial and north west pacific and north phillipine sea are reconstructed clay minerals in sediments particularly marine sediments can be useful indicators of paleoclimatic conditions while they do not produce direct indications of climatic parameters they provide integrated records of overall climatic impact occasionally they may be superior to the more conventional paleoclimatic methods such as pollen or oxygen isotope analysis the limitations imposed on the paleoclimatic interpretation of clay minerals in sediments are discussed on the basis of examples the distinction between authigenic and detrital clay minerals is shown to be problematic particularly with regard to smectite the relationship between climatic parameters and clay mineral formation is complicated by the intervention of extra climatic factors such as topography geomorphology lithology and time post depositional diagenetic changes may not be recognized differentiation during transport due to size sorting or differential flocculation may overlap climate induced differentiation the association of clay mineral assemblages with specific source areas presents difficulties due to dispersal pathways that are affected by type of transport agency i e water ice or wind transport agencies are not constant with time by an interdisciplinary approach with the paleoclimatic information derived from clay minerals being correlated with that obtained from the analysis of microfossils and oxygen isotope data many of these limitations can be overcome

coseismic slip and afterslip of the great mw 9 15 sumatra andaman earthquake of 2004 we determine coseismic and the first month postseismic deformation associated with the sumatra andaman earthquake of 26 december 2004 from near field global positioning system gps surveys in northwestern sumatra and along the nicobar andaman islands continuous and campaign gps measurements from thailand and malaysia and in situ and remotely sensed observations of the vertical motion of coral reefs the coseismic model shows that the sunda subduction mega thrust ruptured over a distance of about 1500 km and a width of less than 150 km releasing a total moment of 6 7 7 0 10 22 n m equivalent to a magnitude m w 9 15 the latitudinal distribution of released moment in our model has three distinct peaks at about 4 n 7 n and 9 n which compares well to the latitudinal variations seen in the seismic inversion and of the analysis of radiated t waves our coseismic model is also consistent with interpretation of normal modes and with the amplitude of very long period surface waves the tsunami predicted from this model fits rela tively well the altimetric measurements made by the jason and topex satellites neither slow nor delayed slip is needed to explain the normal modes and the tsunami wave the near field geodetic data that encompass both coseismic deformation and up to 40 days of postseismic deformation require that slip must have continued on the plate interface after the 500 sec long seismic rupture the postseismic geodetic moment of about 2 4 10 22 nm mw 8 8 is equal to about 30 5 of the coseismic moment release evolution of postseismic deformation is consistent with rate strengthening frictional afterslip online material summary of geodetic data used in this study

deep sea observations and modeling of the 2004 sumatra tsunami in drake passage 1 the 2004 sumatra tsunami was clearly recorded by two uk bottom pressure gauges dpn and dps deployed in drake passage between south america and antarctica these open ocean records were examined to estimate characteristics of the tsunami waves and to compare the results of numerical simulations with the observations maximum wave heights measured at these gauges were 4 9 cm at dpn and 7 4 cm at dps the travel times from the source area were 19 h 46 min and 19 h 39 min respectively consistent with the times obtained from the nearby coastal tide gauges the numerical model described well the frequency content amplitudes and general structure of the observed waves with only small time shifts probably related to wave dispersion effects the shifts were 15 min for dpn and 10 min for dps with the modeled waves leading the observations in each case further inspection of the simulated and observed records revealed that the identified tsunami waves are related to the second main train of waves propagating by the energy conserving route along the mid ocean ridges while the first train of waves travelling by the fastest route across the ocean remained unrecognizable in the observed dps and dpn records and undetectable in the records of coastal tide gauges because of their insignificant amplitudes compared to the background variability

consistent estimates of tsunami energy show promise for improved early warning early tsunami warning critically hinges on rapid determination of the tsunami hazard potential in real time before waves inundate critical coastlines tsunami energy can quickly characterize the destructive potential of generated waves traditional seismic analysis is inadequate to accurately predict a tsunami s energy recently two independent approaches have been proposed to determine tsunami source energy one inverted from the deep ocean assessment and reporting of tsunamis dart data during the tsunami propagation and the other derived from the land based coastal global positioning system gps during tsunami generation here we focus on assessing these two approaches with data from the march 11 2011 japanese tsunami while the gps approach takes into consideration the dynamic earthquake process the dart inversion approach provides the actual tsunami energy estimation of the propagating tsunami waves both approaches lead to consistent energy scales for previously studied tsunamis encouraged by these promising results we examined a real time approach to determine tsunami source energy by combining these two methods first determine the tsunami source from the globally expanding gps network immediately after an earthquake for near field early warnings and then to refine the tsunami energy estimate from nearby dart measurements for improving forecast accuracy and early cancelations the combination of these two real time networks may offer an appealing opportunity for early determination of the tsunami threat for the purpose of saving more lives and early cancelation of tsunami warnings to avoid unnecessary false alarms

a comparative analysis of coastal and open ocean records of the great chilean tsunamis of 2010 2014 and 2015 off the coast of mexico the three great earthquakes off the coast of chile on 27 february 2010 maule mw 8 8 1 april 2014 iquique mw 8 2 and 16 september 2015 illapel mw 8 3 generated major transoceanic tsunamis that spread throughout the pacific ocean and were measured by numerous coastal tide gauges and open ocean dart stations statistical and spectral analyses of the tsunami waves from the events recorded on the pacific coast of mexico enabled us to estimate parameters of the waves along the coast and to compare statistical features of the events we also identified three coastal hot spots sites having maximum tsunami risk puerto angel puerto madero and manzanillo based on the joint spectral analyses of the tsunamis and background noise we have developed a method for using coastal observations to determine the underlying spectrum of tsunami waves in the deep ocean the reconstructed open ocean tsunami spectra are in close agreement with the actual tsunami spectra evaluated from direct analysis of the dart records offshore of mexico we have further used the spectral estimates to parameterize the energy of the three chilean tsunamis based on the total open ocean tsunami energy and frequency content of the individual events

the great sumatra andaman earthquake of 26 december 2004 the two largest earthquakes of the past 40 years ruptured a 1600 kilometer long portion of the fault boundary between the indo australian and southeastern eurasian plates on 26 december 2004 seismic moment magnitude mw 9 1 to 9 3 and 28 march 2005 mw 8 6 the first event generated a tsunami that caused more than 283 000 deaths fault slip of up to 15 meters occurred near banda aceh sumatra but to the north along the nicobar and andaman islands rapid slip was much smaller tsunami and geodetic observations indicate that additional slow slip occurred in the north over a time scale of 50 minutes or longer

chemical evolution of shallow groundwater along the northeast shore of mono lake california we attempted to quantitatively discriminate between hypothesized sources and geochemical processes responsible for the chemical evolution of shallow groundwater along the northeast shore of mono lake an alkaline saline lake located in a hydrologically closed basin in east central california shallow groundwater samples from 17 sites perpendicular and 11 sites parallel to the lakeshore were analyzed for major ions the shallow groundwater contains remnant solutes from higher lake stands which are transported toward the lake by lateral flow and surface runoff the flow system appears to be segregated into two different regions a concentrated highly saline groundwater underlying much of the northeast shore and pockets of more localized lower salinity groundwater the saturation state of the groundwater with respect to certain minerals was determined and simulations for both evaporative concentration of inflow and mixing of lake water with inflow coupled with mineral precipitation were performed solute trends in the shallow groundwater result primarily from the degree of mixing with historical lake water however evaporative concentration and redissolution cycles along with various chemical fractionation mechanisms including ca mg and na carbonate precipitation sulfate reduction ion exchange and potentially mg silicate formation are also important controls

the tsunami of 26 december 2004 numerical modeling and energy considerations a numerical model for the global tsunamis computation constructed by kowalik et al 2005 is applied to the tsunami of 26 december 2004 in the world ocean from 80 s to 69 n with spatial resolution of one minute because the computational domain includes close to 200 million grid points a parallel version of the code was developed and run on a cray x1 supercomputer an energy flux function is used to investigate energy transfer from the tsunami source to the atlantic and pacific oceans although the first energy input into the pacific ocean was the primary direct wave reflections from the sri lankan and eastern shores of maldives were a larger source the tsunami traveled from indonesia around new zealand and into the pacific ocean by various routes the direct path through the deep ocean to north america carried miniscule energy while the stronger signal traveled a considerably longer distance via south pacific ridges as these bathymetric features amplified the energy flux vectors travel times for these amplified energy fluxes are much longer than the arrival of the first wave these large fluxes are organized in the wave like form when propagating between australia and antarctica the sources for the larger fluxes are multiple reflections from the seychelles maldives and a slower direct signal from the bay of bengal the energy flux into the atlantic ocean shows a different pattern since the energy is pumped into this domain through the directional properties of the source function the energy flow into the pacific ocean is approximately 75 of the total flow to the atlantic ocean in many locations along the pacific and atlantic coasts the first arriving signal or forerunner has lower amplitude than the main signal which often is much delayed understanding this temporal distribution is important for an application to tsunami warning and prediction

remote laser induced breakdown spectroscopy libs for lunar exploration 1 laser induced breakdown spectroscopy libs is an active analytical technique that makes use of a laser pulse to analyze materials of interest at a distance by creating a plasma which emits photons at characteristic emission line wavelengths we validate the technique for planetary exploration under vacuum conditions we review the capability and advantages of the libs technique for lunar regolith analysis at 1 5 m distance from a lunar rover and we characterize its potential for the detection of resources for future exploration such as the determination of regolith water content the limits of detection determined for the major elements typically 1 wt help to determine regolith parent material such as feldspathic highland rocks rocks from the ancient magmatic high magnesian suite mg suite fe rich mare basalts or potassium rare earth element and phosphorus rich kreep rich samples compositional parameters commonly used to classify lunar regoliths such as tio2 al2o3 and k2o abundances are readily determined by libs certain elements support regolith analysis for example ba and zr can be used to confirm kreep like composition while quantifying the ni and co content can be used to infer the amount of meteoritic material finally it is shown that the ice content of lunar soil produces strong h emissions with the libs techniques at the 25 wt h2o level while measurements on altered basalts give a limit of detection of about 1 wt for h2o content this demonstrates that the 5 6 wt water content detected by the recent lcross experiment should be easily detectable and quantifiable by libs analysis

introduction to tsunami science ten years after the 2004 indian ocean tsunami volume i twenty papers on the study of tsunamis and respective tsunamigenic earthquakes are included in volume ii of the pageoph topical issue tsunami science ten years after the 2004 indian ocean tsunami the papers presented in this second of two special volumes of pure and applied geophysics reflect the state of tsunami science during this time including five papers devoted to new findings specifically in the indian ocean two papers compile results from global observations and eight papers cover pacific ocean studies focusing mainly on the 2011 tohoku earthquake and tsunami remaining papers in this volume describe studies in the atlantic ocean and mediterranean sea and tsunami source studies overall the volume not only addresses the pivotal 2004 indian ocean and 2011 tohoku tsunamis but also examines the tsunami hazard posed to other critical coasts in the world

chemistry of the apollo 11 highland component chemical data 28 major minor and trace elements were obtained by instrumental neutron activation analysis inaa for 38 hand picked highland fragments 1 20 mg from coarse fines 10085 the apollo 11 highland chemical groups are represented by a range of petrographic types six major chemical highland groups are identified in the apollo 11 fragments these are 1 high k kreep 2 anorthosite e g 15415 60015 with 10 chondrite rare earth elements ree abundances a positive eu anomaly anorthosite with 30 chondrite abundances and a positive eu anomaly 3 anorthosite norite troctolite ant 67075 4 low k fra mauro lkfm 77135 5 anorthositic gabbro 68415 with no eu anomaly anorthositic gabbro 65055 67955 with a positive eu anomaly and anorthositic gabbro 68516 60015 with a negative eu anomaly and 6 apollo 11 dominant highland component 2 10 chondrite ree abundances with a positive 10 14 chondrite eu anomaly there are three newly recognized groups in the apollo 11 highland suite based on the ree patterns these are a ant with 5 chondrite la 22 chondrite abundances and a positive eu anomaly b 10 chondrite flat pattern with 14 chondrite positive eu anomaly and c 2 3 chondrite flat pattern with 10 chondrite positive eu anomaly the apollo 11 highland suite is very low in potassium non kreepy overall the apollo 11 highland suite is quite similar to the apollo 16 suite most previously recognized highland chemical groups are represented in the apollo 11 highland component

direct energy estimation of the 2011 japan tsunami using deep ocean pressure measurements 1 we have developed a method to compute the total energy transmitted by tsunami waves to the case where the earthquake source is unknown by using deep ocean pressure measurements and numerical models tsunami source functions based on the first wave recorded at the two closest tsunameters deep ocean assessment and reporting of tsunamis dart our analysis suggests that the march 11 2011 tohoku oki tsunami generated off japan originated from a 300 400 km long and 100 km wide area and the total propagated energy is 3 1015j with 6 uncertainty measurements from 30 tsunameters and 32 coastal tide stations show excellent agreement with the forecasts obtained in real time our study indicates that the propagated energy and the source location are the most important source characteristics for predicting tsunami impacts interactions of tsunami waves with seafloor topography delay and redirect the energy flux posing hazards from delayed and amplified waves with long duration seafloor topography also gives its spectral imprint to tsunami waves travel time forecast errors are path specific and correlated to the major wave scatterers in the pacific numerical dissipation in the propagation modeling highlights the need of high resolution inundation models for accurate coastal predictions on the other hand it also can be used to account for physical dissipation to achieve efficiency our results provide guidelines for the earliest reliable tsunami forecast warnings of long duration tsunami waves signals and enhancement of the experimental tsunami forecast system we apply the method to quantify the energy of 15 past tsunamis independently from earthquake magnitudes the small tsunami to seismic radiation energy ratios and their variability 0 01 0 8 reinforce the importance of using deep ocean tsunami data the direct measures of tsunamis for estimates of tsunami energy and accurate forecasting

tsunami source of the 2004 sumatra andaman earthquake inferred from tide gauge and satellite data tsunami source of the 2004 sumatra andaman earthquake was esti mated from a joint inversion of tsunami waveforms recorded on tide gauges and sea surface heights captured by satellite altimetry measurements the earthquake the largest in the past 40 years caused devastating tsunami damage to countries around the indian ocean but the tsunami source in particular its northern end was not well resolved although aftershocks and crustal deformation extended from off north western sumatra island through the nicobar islands to the andaman islands some seismic wave analyses indicated a shorter source length several hundred kilometers we used tsunami waveforms recorded at 12 tide gauge stations around the source and the sea surface heights measured by three satellites jason1 topex poseidon and envisat we numerically computed tsunami propagation using realistic bathym etry more than 66 000 depth points were digitized from nautical charts and combined with the etopo2 data inversion of satellite data indicates that the tsunami source extended to the andaman islands with a total length of 1 400 km but such a model produces much larger tsunami waveforms than observed at indian tide gauge stations inversion of tide gauge records and the joint inversion indicate that the tsunami source was about 900 km long the largest slip about 13 to 25 m was located off sumatra island and the second largest slip up to 7 m near the nicobar islands the slip distribution is similar for different rupture velocities and rise times with a slow velocity of 1 km sec and a rise time of 3 min yielding the largest variance reduction

constraining the source regions of lunar meteorites using orbital geochemical data lunar meteorites provide important new samples of the moon remote from regions visited by the apollo and luna sample return missions petrologic and geochemical analysis of these meteorites combined with orbital remote sensing measurements have enabled additional discoveries about the composition and age of the lunar surface on a global scale however the interpretation of these samples is limited by the fact that we do not know the source region of any individual lunar meteorite here we investigate the link between meteorite and source region on the moon using the lunar prospector gamma ray spectrometer remote sensing data set for the elements fe ti and th the approach has been validated using apollo and luna bulk regolith samples and we have applied it to 48 meteorites excluding paired stones our approach is able broadly to differentiate the best compositional matches as potential regions of origin for the various classes of lunar meteorites basaltic and intermediate fe regolith breccia meteorites are found to have the best constrained potential launch sites with some impact breccias and pristine mare basalts also having reasonably well defined potential source regions launch areas for highland feldspathic meteorites are much less well constrained and the addition of another element such as mg will probably be required to identify potential source regions for these

level of lake lahontan during deposition of the trego hot springs tephra about 23 400 years ago abstract the trego hot springs tephra bed is a silicic tephra about 23 400 yr old found at several localities in pluvial lake sediments in northern nevada southern oregon and northeastern california it has been characterized petrographically by the major and minor element chemistry of its glass and by its stratigraphic position with respect to other tephra layers at a newly described locality on squaw creek northwest of gerlach nevada at the north end of the smoke creek desert trego hot springs tephra has been found in sediments of the sehoo and indian lakes formations the depositional environments of these sediments show that when the tephra fell pluvial lake lahontan stood between 1256 and 1260 m and that immediately thereafter the lake rose to at least 1275 m these data corroborate earlier findings by benson quaternary research 9 300 318 from radiometric dating of calcareous tufa however the lake lahontan area has been affected by isostatic subsidence and rebound in response to changing water loads so that caution is required in the use of lakeshore elevations in correlation

numerical tsunami simulation including elastic loading and seawater density stratification systemic discrepancies between observed and modeled tsunami wave speeds were previously identified for two recent major tsunamis the 2010 maule and 2011 tohoku events to account for these discrepancies we developed a numerical tsunami propagation code solving the shallow water equation and including the effects of elastic loading of the seafloor by the tsunami as well as a linear density profile in the seawater column we show here that both effects are important to explain the commonly observed difference between observations and simulations we conclude that the density variation in the seawater column affects the wave speed without changing the waveform whereas the loading effect has an effect on the wave speed and the waveform showing a negative phase before the main arrival due to the depression of the seafloor surrounding the tsunami wave the combination of both effects is needed to achieve a better match between observations and simulations

the lithium isotopic composition of waters of the mono basin california mono lake a major closed basin alkaline salt lake in eastern california derives its water from a mixture of creeks and springs with the former providing in excess of 75 of the total the li isotopic composition of lake water has not varied significantly over a 4 year meromictic period 7li 19 5 springs are isotopically distinct groundwater springs and seeps carry water enriched in isotopically heavy li whereas thermal springs supply isotopically light 7li 50 of the li to the lake 2 the li budget is sensitively balanced on small thermal spring contributions 3 of the total spring inflow and 3 the residence time of li in the lake is 28 ka other great basin closed lakes have variable li isotopic compositions 7li from 16 7 to 23 7 all of which differ significantly from those of several major lakes and seawater homogeneously 32

chemistry and petrology of apollo 12 drive tube 12027 modal and chemical data for 31 major minor and trace elements obtained by inaa for soils from four 5 cm depth intervals of drive tube 12027 show three compositional units within the core the upper 2 5 cm of 12027 represent part of the sharp crater rim crest deposit which has a total thickness of 23 cm chemical differences are attributed to addition of local mare rocks to the upper 2 cm and kreepy material to the lower stratigraphic layer 14 17 cm depth the coarser fractions 1000 90 90 20 and 20 10 pm are compositionally similar to each other but quite different from the 10 m fine fractions which are more feldspathic and enriched in incompatible lil elements correlation between fused soil contents and lil enrichments of the coarse fractions strongly suggests that agglutinates are derived from the fine fraction thus supporting the fusion of the finest fraction f3 model the trench soil 12033 from 15 cm depth is very similar to the 15 5 16 cm soil of core 12027 indicating that the apollo 12 regolith exhibits kreep enrichments at various depths and that exotic kreepy ejecta are wide spread at the apollo 12 site

traveltime delay and initial phase reversal of distant tsunamis coupled with the self gravitating elastic earth systematic tsunami traveltime delays of up to 15 min relative to the numerically simulated long waves from the 2010 chilean and 2011 tohoku oki earthquakes were widely observed at deep ocean tsunamimeters enigmatic small negative phases appearing before the main peak were commonly found only at the trans oceanic locations the frequency dependence of the measured tsunami phase velocities shows reverse dispersions at long periods i e the tsunami speed becomes slower at periods beyond 1000 s this is consistent with the phase velocities of a tsunami mode coupled with a self gravitating elastic earth suggesting that the effects of compression and dilatation of seawater elastic tsunami loadings on a solid earth and the geopotential variations associated with the motion of mass during tsunami propagation are responsible for the traveltime delays and the initial negative phases simple 1 d tsunami propagation tests confirm that the reverse dispersion creates a small negative phase that precedes the main peak at large distances a new method to simulate tsunami waveforms on real ocean bathymetry that takes into account seawater compressibility the elasticity of the earth and geopotential perturbations has been developed by applying a phase correction to the simulated long waves the simulated waveforms in which phase corrections are applied for the dispersion effects accurately reproduce the observed waveforms including a small initial negative phase that appears at distant locations the traveltime difference between the observed and simulated waveforms has been decreased to less than 5 min and the waveform difference between them remarkably diminishes

petrology of apollo 11 regolith breccias petrographic and mineral chemical data for 16 apollo 11 regolith breccias show that 1 the regolith breccias differ from soil 10084 with respect to a agglutinate content b glass population c plagioclase compositions and d proportions of high k mare and low k mare basalt components 2 the a 11 breccias and soil have highland components that are similar both in abundance and petrology and 3 lunar regolith breccias provide a better comparison with howardites than do lunar soils the data and observations are consistent with formation of the regolith breccias from immature soil it appears that little or no highland material has been added to the tranquillitatis regolith since the formation of the breccias

chlorine 36 in great basin waters revisited inspired by recently published chloride balance chronologies of closed basin lakes in the great basin researchers of the early 1960s attempted to estimate residence times of chloride in these lakes using 36cl unfortunately the analytical methods of the period were not capable of measuring the 36cl levels found in these waters about 20 years after the early research advances in accelerator mass spectrometry permitted 36cl measurement at the required sensitivity in this study we follow up on those pioneering efforts by remeasuring and reevaluating the 36cl content at several of the previously studied sites focusing on mono lake in eastern california our data show that in general the streams in the region have 36cl cl ratios similar to those expected in present day atmospheric fallout but that the terminal lakes into which the streams flow have much lower ratios these lower ratios could result from either a very long 1 million years residence time of the chloride in the basin sinks or from subsurface influx of low 36cl chloride in the case of mono lake a mass balance model based on the 36cl data and on independent estimates of chloride fluxes and reservoirs indicates major subsurface chloride input presumably from volcanic sources and an accumulation time in the range of 100 450 kyr the upper bound of this range is similar to the timing of a shift from long term humid to arid climate in the region and may indicate that hydrological closure of the basin was triggered by this event

extreme inundation flows during the hokkaido nansei oki tsunami the tsunami generated by the july 12 1993 hokkaido nansei oki mw 7 8 earthquake produced in japan the worst local tsunami related death toll in fifty years with estimated 10 18m sec overland flow velocities and 30m runup these extreme values are the largest recorded in japan this century and are among the highest ever documented for non landslide generated tsunamis we model this event to confirm the estimated overland flow velocities and we find that given reasonable ground deformation data current state of the art shallow water wave models can predict tsunami inundation correctly including extreme runup current velocities and overland flow we find that even small local topographic structures affect the runup to first order and that the resolution of the bathymetric data is more important than the grid resolution our results qualitatively suggest that for this event coastal inundation is more correlated with inundation velocities than with inundation heights explaining also why threshold type modeling has substantially underpredicted coastal inundation for this and other recent events

real time experimental forecast of the peruvian tsunami of august 2007 for u s coastlines 1 at 23 41 utc on 15 august 2007 an offshore earthquake of magnitude 8 0 severely damaged central peru and generated a tsunami severe shaking by the earthquake collapsed buildings throughout the region and caused 514 fatalities the tsunami resulted in three casualties and a representative maximum runup height of 7 m in the near field the first real time tsunami data available came from a deep ocean tsunami detection buoy within 1 hour of tsunami generation these tsunami data were used to produce initial experimental forecasts within 2 hours of tsunami generation the far field forecasts indicated that the tsunami would not flood any of the 14 u s communities comparison with real time tide gage data showed very accurate forecasts

last glacial maximum and holocene lake levels of owens lake eastern california usa abstract stratigraphic investigations of fluvio deltaic and lacustrine sediments exposed in stream cuts quarry walls and deep trenches east of the sierra nevada in owens valley near lone pine california have enabled the reconstruction of pluvial owens lake level oscillations age control for these sediments is from 22 radiocarbon 14 c dates and the identification and stratigraphic correlation of a tephra which when plotted as a function of age versus altitude define numerous oscillations in the level of pluvial owens lake during the latest pleistocene and early holocene we have constructed a lake level altitude curve for the time interval 27 000 cal yr bp to present that is based on the integration of this new stratigraphic analysis with published surface stratigraphic data and subsurface core data pluvial owens lake regressed from its latest pleistocene highstands from 27 000 to 15 300 cal yr bp as recorded by 15 m of down cutting of the sill from the altitudes of 1160 to 1145 m by 11 600 cal yr bp the lake had dropped 45 m from the 1145 m sill this lowstand was followed by an early holocene transgression that attained a highstand near 1135 m before dropping to 1120 m at 7860 7650 cal yr bp that had not been recognized in earlier studies the lake then lowered another 30 m to shallow and near desiccation levels between 6850 and 4300 cal yr bp fluvial cut and fill relations north of lone pine and well preserved shoreline features at 1108 m indicate a minor lake level rise after 4300 cal yr bp followed by alkaline and shallow conditions during the latest holocene the new latest quaternary lake level record of pluvial owens lake offers insight to the hydrologic balance along the east side of the southern sierra nevada and will assist regional paleoclimatic models for the western basin and range

ikaite precipitation by mixing of shoreline springs and lake water mono lake california usa abstract metastable ikaite caco3 6h2o forms abundantly during winter months along the south shoreline of mono lake where shoreline springs mix with lake water ikaite precipitates because of its decreased solubility at low temperature and because of orthophosphate ion inhibition of calcite and aragonite during the spring some of the ikaite is transformed to anhydrous caco3 and is incorporated into tufa but most is dispersed by wave action into the lake where it reacts to form gaylussite na2ca co3 2 5h2o spring waters have low ph values are dominantly ca na hco3 have low radiocarbon activities and are mixtures of deep seated geothermal and cold groundwaters chemical modeling reveals that precipitation of caco3 can occur over a broad range of mixtures of spring and lake water with a maximum production occurring at 96 spring water and 4 lake water under these conditions all the ca and a significant fraction of the co3 of the precipitate is spring supplied a radiocarbon age of 19 580 years obtained on a natural ikaite sample supports this conclusion with the springs supplying a large and probably variable portion of the carbonate and with apparent 14c age of the carbonate varying from spring to spring tufa of similar actual antiquity may yield significantly different 14c dates making tufa at this location unsuitable for absolute age dating by the radiocarbon method

re examination of the formation ages of the apollo 16 regolith breccias abstract the lunar regolith is exposed to irradiation from the solar wind and to bombardment by asteroids comets and inter planetary dust fragments of projectiles in the lunar regolith can potentially provide a direct measure of the sources of exogenous material being delivered to the moon constraining the temporal flux of their delivery helps to address key questions about the bombardment history of the inner solar system here we use a revised antiquity calibration after eugster et al 2001 that utilises the ratio of trapped 40 ar 36 ar parentless 40 ar derived from radioactive decay of 40 k against solar wind derived 36 ar to semi quantitatively calculate the timing of the assembly of the apollo 16 regolith breccias we use the trapped 40 ar 36 ar ratios reported by mckay et al 1986 our model indicates that the apollo 16 ancient regolith breccia population was formed between 3 8 and 3 4 ga consistent with regoliths developed and assembled after the imbrium basin forming event at 3 85 ga and during a time of declining basin forming impacts the material contained within the ancient samples potentially provides evidence of impactors delivered to the moon in the late imbrian epoch we also find that a young regolith population was assembled probably by local impacts in the apollo 16 area in the eratosthenian period between 2 5 and 2 2 ga providing insights to the sources of post basin bombardment the soil like regolith breccia population and the majority of local apollo 16 soils were likely closed in the last 2 ga and therefore potentially provide an archive of projectile types in the eratosthenian and copernican periods

chronology of expansion and contraction of four great basin lake systems during the past 35 000 years abstract during the past 35 000 years lake bonneville lake russell and lake searles underwent a major period of lake level change the lakes were at moderate levels or dry at the beginning of the period and seem to have achieved highstands between about 15 000 and 13 500 yr b p the rise of lake lahontan was gradual but not continuous in part because of topographic constraints intrabasin spill lake lahontan also had an oscillation in lake level at 15 500 yr b p radiocarbon age estimations for materials that were deposited in the lake basins indicate that lake bonneville rose more or less gradually from 32 000 yr b p and had major oscillations in level between 23 000 and 21 000 yr b p and between 15 250 and 14 500 yr b p lake russell and lake searles had several major oscillations in lake level between 35 000 and 14 000 yr b p the timing and exact magnitude of the oscillations are difficult to decipher but both lakes may have achieved multiple highstand states all four lakes may have had nearly synchronous recessions between about 14 000 and 13 500 yr b p after the recessions the lakes seem to have temporarily stabilized or experienced a minor increase in size between about 11 500 and 10 000 yr b p these data provide circumstantial evidence that the younger dryas event affected climate on at least a hemispheric scale during the holocene the four lakes remained at low levels and small oscillations in lake level occurred an important aspect of the lake level data is the accompanying expansion of lake surface area at the time of the last highstand lake bonneville and lake lahontan had surface areas about 10 times larger than their mean historical reconstructed areas whereas lake russell and lake searles had surface areas about 5 times larger than their mean historical reconstructed areas differences in the records of effective wetness may have been due to the locations of the basins relative to the position of the jetstream or they may have resulted from lake atmosphere feedback processes

lake level variation in the lahontan basin for the past 50 000 years selected radiocarbon data on surficial materials from the lahontan basin nevada and california provide a chronology of lake level variation for the past 50 000 yr a moderate sized lake connected three western lahontan subbasins the smoke creek black rock desert subbasin the pyramid lake subbasin and the winnemucca dry lake subbasin from about 45 000 to 16 500 yr b p between 50 000 and 45 000 yr b p walker lake rose to its sill level in adrian valley and spilled to the carson desert subbasin by 20 000 yr b p lake level in the western lahontan subbasins had risen to about 1265 m above sea level where it remained for 3500 yr by 16 000 yr b p lake level in the western lahontan subbasins had fallen to 1240 m this recession appears synchronous with a desiccation of walker lake however whether the walker lake desiccation resulted from climate change or from diversion of the walker river is not known from about 15 000 to 13 500 yr b p lake level rapidly rose so that lake lahontan was a single body of water by 14 000 yr b p the lake appears to have reached a maximum highstand altitude of 1330 m by 13 500 yr b p a condition that persisted until about 12 500 yr b p at which time lake level fell 100 m no data exist that indicate the level of lakes in the various subbasins between 12 000 and 10 000 yr b p during the holocene the lahontan basin was the site of shallow lakes with many subbasins being the site of one or more periods of desiccation the shape of the lake level curve for the three western subbasins indicates that past changes in the hydrologic balance and hence climate of the lahontan basin were large in magnitude and took place in a rapid step like manner the rapid changes in lake level are hypothesized to have resulted from changes in the mean position of the jet stream as it was forced north or south by the changing size and shape of the continental ice sheet

the 21 may 2003 tsunami in the western mediterranean sea statistical and wavelet analyses we report the statistical and wavelet analyses of the 21 may 2003 tsunami produced by an mw 6 8 6 9 thrust earthquake in the western mediterranean sea using 19 tide gauge records the largest trough to crest wave height was 196 cm recorded at the sant antoni station in the lee of the incoming tsunami wave except at one station the first wave was not the largest wave at all the analyzed stations and the largest wave arrived several hours after the first arrival in addition the tsunami waves persisted for more than 1 day at most stations as the spectra of coastal tide gauge stations are strongly influenced by topographic features special care was taken here while interpreting the results of spectral and wavelet analysis our wavelet analysis shows that only a peak at around 23 min is persistent for long duration and other peaks at 14 30 45 and 60 min appeared at short durations the 23 min signal is possibly associated with the width of the source fault whereas the fault length contributed to the 45 min signal based on these dominant periods the tsunami source dimensions are estimated as 95 km 45 km the statistical and wavelet analyses performed here provide some new insights into the characteristics of the tsunami that was generated and propagated in the western mediterranean basin

the 26 december 2004 sumatra tsunami analysis of tide gauge data from the world ocean part 1 indian ocean and south africa the m w 9 3 megathrust earthquake of december 26 2004 off the northwest coast of sumatra in the indian ocean generated a catastrophic tsunami that was recorded by a large number of tide gauges throughout the world ocean part 1 of our study of this event examines tide gauge measurements from the indian ocean region at sites located from a few hundred to several thousand kilometers from the source area statistical characteristics of the tsunami waves including wave height duration and arrival time are determined along with spectral properties of the tsunami records

the global reach of the 26 december 2004 sumatra tsunami numerical model simulations combined with tide gauge and satellite altimetry data reveal that wave amplitudes directionality and global propagation patterns of the 26 december 2004 sumatra tsunami were primarily determined by the orientation and intensity of the offshore seismic line source and subsequently by the trapping effect of mid ocean ridge topographic waveguides

climatic and hydrologic oscillations in the owens lake basin and adjacent sierra nevada california oxygen isotope and total inorganic carbon values of cored sediments from the owens lake basin california indicate that owens lake overflowed most of the time between 52 500 and 12 500 carbon 14 14 c years before present b p owens lake desiccated during or after heinrich event h1 and was hydrologically closed during heinrich event h2 the magnetic susceptibility and organic carbon content of cored sediments indicate that about 19 sierra nevada glaciations occurred between 52 500 and 23 500 14 c years b p most of the glacial advances were accompanied by decreases in the amount of discharge reaching owens lake comparison of the timing of glaciation with the lithic record of north atlantic core v23 81 indicates that the number of mountain glacial cycles and the number of north atlantic lithic events were about equal between 39 000 and 23 500 14 c years b p

double jeopardy concurrent arrival of the 2004 sumatra tsunami and storm generated waves on the atlantic coast of the united states and canada 1 a detailed analysis of over one hundred tide gauge records from the atlantic coast of north america reveals that the arrival of the 26 december 2004 sumatra tsunami on this coast coincided with the presence of tsunami like waves being generated by a major storm tracking northward along the eastern seaboard of the united states according to the tide gauge records waves from the two events coalesced along the shores of maine and nova scotia on 27 december where they produced damaging waves with heights in excess of 1 m tsunami waves were identified in almost all outer tide gauges from florida to nova scotia with maximum tsunami heights for the northern regions estimated to be 32 39 cm in the south maximum tsunami wave heights were in the range of 15 to 33 cm

climatic oscillations 10 000 155 000 yr b p at owens lake california reflected in glacial rock flour abundance and lake salinity in core ol 92 earlier wetter cycles the lake overflowed to fill a series chemical analyses of the acid soluble and clay size fractions of of downstream basins including china lake basin searles sediment samples 1500 yr resolution reveal oscillations of lake valley panamint valley and ultimately death valley salinity and of glacial advances in core ol 92 back to 155 000 yr smith and street perrott 1983 in 1992 the u s geological b p relatively saline conditions are indicated by the abundance survey drilled a 323 m deep core ol 92 into owens lake of carbonate and smectite both pedogenic and authigenic re sediments near the depocenter of the basin to obtain a continflected by ca sr and mg in the acid soluble suite and by cs2o uous record of silty clay sediment spanning the last 800 000 excess mgo and loi loss on ignition in the clay size fraction yr a multiparameter reconnaissance study of the entire core rock flour produced during glacial advances is represented by ca 7000 yr resolution reported in a 13 chapter summary the abundance of detrital plagioclase and biotite in the clay size volume smith and bischoff 1997 revealed cycles characfraction the ratio of which remains essentially constant over the terized by closed and overflowing lake conditions entire time span these phases are quantitatively represented by na2o tio2 ba and mn in the clay fraction the rock flour record we report here the results of a second part of an intermediindicates two major ice advances during the penultimate glacial ate resolution study aimed at resolving shorter term events cycle corresponding to marine isotope stage mis 6 no major over just the past 155 000 yr using sediment samples of ca advances during the last interglaciation entire mis 5 and three 1500 yr resolution taken over the uppermost 90 m of olmajor advances during the last glacial cycle mis 2 3 and 4 92 the companion study menking et al 1997 reports on the ages of the latter three correspond rather well to 36 cl dates grain size tic total inorganic carbon content and stable reported for sierra nevada moraines the onset of the last intergla isotopic measurements proxies which tend to reflect variaciation is shown by abrupt increases in authigenic caco3 and an tions in water flow and which are most representative of abrupt decrease in rock flour at about 118 000 yr b p according variations during closed lake conditions the present study to our time scale in contrast the boundary appears to be gradual was concerned primarily with seeking a proxy for glacial in the d 18 o record in which the change from light to heavy values advances we found that the mineralogy and chemistry of begins at about 140 000 yrs b p the exact position of the termination therefore may be proxy dependent conditions of high car the clay fraction provide indices of glacial rock flour we bonate and low rock flour prevailed during the entire period from also report on the composition of the acid soluble carbonate 118 000 yr b p until the glacial advance at 53 000 yr b p signaled fraction which gives further detail on closed lake conditions

improved phase corrections for transoceanic tsunami data in spatial and temporal source estimation application to the 2011 tohoku earthquake systemic travel time delays of up to 15 min relative to the linear long waves for transoceanic tsunamis have been reported a phase correction method which converts the linear long waves into dispersive waves was previously proposed to consider seawater compressibility the elasticity of the earth and gravitational potential change associated with tsunami motion in the present study we improved this method by incorporating the effects of ocean density stratification actual tsunami raypath and actual bathymetry the previously considered effects amounted to approximately 74 for correction of the travel time delay while the ocean density stratification actual raypath and actual bathymetry contributed to approximately 13 4 and 9 on average respectively the improved phase correction method accounted for almost all the travel time delay at far field stations we performed single and multiple time window inversions for the 2011 tohoku tsunami using the far field data 3 h travel time to investigate the initial sea surface displacement the inversion result from only far field data was similar to but smoother than that from near field data and all stations including a large sea surface rise increasing toward the trench followed by a migration northward along the trench for the forward simulation our results showed good agreement between the observed and computed waveforms at both near field and far field tsunami gauges as well as with satellite altimeter data the present study demonstrates that the improved method provides a more accurate estimate for the waveform inversion and forward prediction of far field data

the 2011 tohoku tsunami on the coast of mexico a case study the tohoku east japan earthquake of 11 march 2011 m w 9 0 generated a great trans oceanic tsunami that spread throughout the pacific ocean where it was measured by numerous coastal tide gauges and open ocean dart deep ocean assessment and reporting of tsunamis stations statistical and spectral analyses of the tsunami waves recorded along the pacific coast of mexico have enabled us to estimate the principal parameters of the waves along the coast and to compare statistical features of the tsunami with other tsunamis recorded on this coast we identify coastal hot spots manzanillo zihuatanejo acapulco and ensenada corresponding to sites having highest tsunami hazard potential where wave heights during the 2011 event exceeded 1 5 2 m and tsunami induced currents were strong enough to close port operations based on a joint spectral analysis of the tsunamis and background noise we reconstructed the spectra of tsunami waves in the deep ocean and found that with the exception of the high frequency spectral band 5 cph the spectra are in close agreement with the true tsunami spectra determined from dart bottom pressure records the departure of the high frequency spectra in the coastal region from the deep sea spectra is shown to be related to background infragravity waves generated in the coastal zone the total energy and frequency content of the tohoku tsunami is compared with the corresponding results for the 2010 chilean tsunami our findings show that the integral open ocean tsunami energy i 0 was 2 30 cm2 or approximately 1 7 times larger than for the 2010 event comparison of this parameter with the mean coastal tsunami variance 451 cm2 indicates that tsunami waves propagating onshore from the open ocean amplified by 14 times the same was observed for the 2010 tsunami the tsunami colour frequency content for the 2011 tohoku tsunami was red with about 65 of the total energy associated with low frequency waves at frequencies 35 min the red colour i e the prevalence of low frequency waves in the 2011 tohoku as well as in the 2010 chile tsunamis is explained by the large extension of the source areas in contrast the 2014 and 2015 chilean earthquakes had much smaller source areas and consequently induced bluish high frequency tsunamis

the december 2018 anak krakatau volcano tsunami as inferred from post tsunami field surveys and spectral analysis we present analysis of the december 2018 anak krakatau tsunami in sunda strait indonesia from a combination of post tsunami field surveys bathymetric changes and spectral analysis of the tsunami tide gauge records post tsunami surveys revealed moderate tsunami height along the coast of sumatra and java with maximum surveyed runup of 13 5 m and maximum inundation distance of 330 m at small islands located close to the volcano extreme tsunami impacts were observed indicating not only a huge tsunami was generated by large amounts of collapse material which caused notable changes of seafloor bathymetry but also indicates the role of those small islands in reducing tsunami height that propagated to the mainland of indonesia our spectral analysis of tide gauge records showed that the tsunami s dominant period was 6 6 7 4 min indicating the short period nature of the 2018 sunda strait tsunami

source spectrum for the algerian tsunami of 21 may 2003 estimated from coastal tide gauge data 1 on 21 may 2003 a submarine earthquake occurred near algiers producing a tsunami that propagated northward and reached the balearic islands and the levantine coast of the iberian peninsula within an hour despite that the generated tsunami was moderate sea level variations inside certain harbors at the balearic islands were significant producing severe damage to moored boats available tsunami records in the affected harbors are examined to estimate amplifications factors of arriving waves and spectral characteristics of the source comparison between background and tsunami oscillations at various sites allowed separation of the tsunami source properties from local topographic effects the fundamental period of the reconstructed source spectrum is 21 min which is in close agreement with that found by alasset et al 2006 based on modeling the tsunami initiation

petrology and chemistry of apollo 12 regolith breccias petrographic mineral chemical and bulk chemical data are reported for the three large apollo 12 regolith breccias of the regolith breccia suite and for eight breccias handpicked from apollo 12 coarse fines two samples formed from non kreepy anorthositic regolith not presently found at the sampling site eight of the samples can be considered mixtures of local basalt and kreep components with minor anorthositic components mare kreep ratios indicated by chemical mixing models range from 86 7 to essentially endmember kreep one sample is unlike the others feo 23 7 mgo 21 7 and may be a new lithology or alternatively a nonrepresentative sample of the 11 samples studied 5 appear to be of local origin 3 are most likely exotic to the site and results for 3 others are inconclusive the anorthositic breccias formed from apollo 16 like regolith and may have been transported over several hundred kilometers from the non kreepy highlands to the east alternatively they may be of local origin formed from the material beneath the apollo 12 basalt flows

effects of bathymetry on tsunami propagation application of ray tracing to tsunamis ray tracing of seismic surface waves is applied to tsunami propagation to examine bathymetric effect along its propagation path computations are made for trans pacific tsunamis and for near field tsunamis in the japan sea for tsunamis across the pacific ocean the comparison to a uniform ocean shows that focusing and defocusing due to bathymetry are significant for some combinations of source and receiver for example the refraction of rays is predominant at the east pacific rise for the tsunami from chile the tsunamis in the japan sea are strongly affected by the shallow yamato rise the predicted arrival time and amplitude distribution generally agree with the observations from an actual tsunami since the computation can be made very quickly the method is useful for preliminary analysis of tsunami propagation such as in an operational warning system or in the determination of computational area for finite difference computation

history and features of trans oceanic tsunamis and implications for paleo tsunami studies abstract far field tsunamis and their features as well as methods to quantify trans oceanic tsunamis are reviewed with examples of instrumental and historical data tsunamis from the 1854 nankai earthquakes the 1946 aleutian tsunami earthquake the 1960 and 2010 chile earthquakes as well as the 2011 tohoku earthquake were recorded around the pacific ocean the 1883 krakatoa volcanic eruption caused volcanic tsunami in the indian ocean and meteotsunami in the pacific ocean the 2004 indian ocean tsunami was also recorded in the pacific ocean when a tsunami amplitude is larger than that of ocean tides which usually requires the parent earthquake to be gigantic mw 9 it can cause damage and may be historically documented the trans pacific tsunamis described in historical documents include those from the 1700 cascadia earthquake the 1730 1751 1837 and 1877 earthquakes off chile and the 1687 and 1868 earthquakes off peru the tsunami record in japan from the 1586 peru earthquakes was found to be incorrect and should be discounted the tsunami magnitude scale relates the tsunami heights to the earthquake size tsunami travel time can be computed from actual bathymetry and the tsunami ray tracing provides relative amplitudes due to focusing defocusing caused by irregular bathymetry numerical computations from fault models produce tsunami amplitudes and waveforms and indicate strong directivity due to strike of fault or orientation of subduction zones far field tsunamis are often long lasting due to multiple reflections across the basin or on continental shelf or due to resonance in bays harbors these features would provide important criteria to estimate tsunami sources from paleo tsunami data

an experimental investigation of agglutinate melting mechanisms shocked mixtures of apollo 11 and 16 soils mixtures of chemically contrasting lunar soils from a 11 and a 16 have been shocked at pressures ranging from 18 2 62 0 gpa 182 620 kb other than the generation of impact melts modal and textural changes caused by shock include destruction of pore space and fused soil clasts and conversion of plagioclase to maskelynite the loss of the fused soil component in these runs indicates that low agglutinate contents in shocked and or compacted regolith breccias cannot be considered by themselves to be evidence of formation from immature regolith from the petrographic and chemical data it appears that the impact glass formed mainly from the fine fraction and the fused soil component in the target with relatively minor contributions from the other coarse clasts the impact glasses exhibit the same chemical enrichments and depletions as their corresponding fine fractions and plot on or near a mixing line between the bulk and fine fraction of the soil in which they were formed from this as well as several other studies it appears that the fusion of the finest fraction f3 model is valid and that it accurately predicts the chemical systematics of impact glass formed from lunar soil in addition fusion of agglutinates present in the target soil is an important process

apollo 16 regolith breccias and soils recorders of exotic component addition to the descartes region of the moon abstract the subdivision of apollo 16 regolith breccias into ancient 4 b y and relatively younger samples on the basis of trapped 40 ar 36 ar ratios 1 makes possible with the present day soils as a third sample suite a petrologic and chemical determination of regolith evolution and exotic component addition at the a 16 site petrologic data for the ancient breccias show that the early regolith was composed of fragments of plutonic rocks and impact melt rocks and minerals and impact glasses derived from these lithologies the presence of kreepy glasses in the ancient breccias demonstrates that kreepy lithologies and impact melts formed early in lunar history comparison of the ancient breccias with the young breccias and the soils shows that the mare components mainly in the form of orange high tio 2 glass and green low tio 2 glass were mostly added to the site after formation of the ancient breccias and prior to formation of the young breccias the young breccias are petrologically similar to the soils the major change in the regolith since the formation of the young breccias is an increase in maturity the formation of fused soil particles with prolonged exposure to micrometeorite impacts by contrast the breccias formed at times when large impacts and soil mixing were dominant over small impacts and maturation

analytical solutions for estimating tsunami propagation speeds abstract recent studies suggest that the tsunami speed can be slowed down by around 1 due to earth elasticity water compressibility and density stratification analytical solutions of wave dispersion relationship accounting for such effects were found in previous studies in this paper we investigate the additional effects of water viscosity ocean stratification due to temperature salinity and numerical dispersion theoretical solutions are derived and checked with known solutions all the formulas are then simplified for long tsunamis waves so that the propagation speed can be calculated explicitly the simplified solutions are evaluated using realistic geophysical parameters for a typical tsunami wavelength of 200km the viscous effect is found to be negligible ocean stratification due to temperature salinity causes significant speed reduction because of the high density change rate which has been ignored before we also evaluate the numerical dispersion of tsunami simulations which is shown to be potentially comparable to physical dispersion

the 2017 mexico tsunami record numerical modeling and threat assessment in costa rica an mw 8 2 earthquake and tsunami occurred offshore the pacific coast of mexico on 2017 09 08 at 04 49 utc costa rican tide gauges have registered a total of 21 local regional and far field tsunamis the quepos gauge registered 12 tsunamis between 1960 and 2014 before it was relocated inside a harbor by late 2014 where it registered two more tsunamis this paper analyzes the 2017 mexico tsunami as recorded by the quepos gauge it took 2 h for the tsunami to arrive to quepos with a first peak height of 9 35 cm and a maximum amplitude of 18 8 cm occurring about 6 h later as a decision support tool this tsunami was modeled for quepos in real time using commit community model interface for tsunami with the finer grid having a resolution of 1 arcsec 30 m however the model did not replicate the tsunami record well probably due to the lack of a finer and more accurate bathymetry in 2014 the national tsunami monitoring system of costa rica sinamot was created acting as a national tsunami warning center the occurrence of the 2017 mexico tsunami raised concerns about warning dissemination mechanisms for most coastal communities in costa rica due to its short travel time

potential mass movements on the palinuro volcanic chain southern tyrrhenian sea italy and consequent tsunami generation abstract the palinuro volcanic chain pvc is located about 80 km offshore the campania region italy in the southern sector of the tyrrhenian sea the chain consists of 15 volcanic edifices aligned in an e w direction with two distinct major seamounts palinuro and glabro they cover a 90 km long and 20 km wide area with a present day volume of 2700 km3 palinuro volcanism emplaced between 0 8 and 0 3 ma although shallow seismicity and hydrothermalism indicate an ongoing volcanic activity a geomorphological analysis of the volcanic chain and data from a multichannel seismic profile reveal large volumes of buried chaotic material suggesting gravity mass sliding from the volcano flanks and slide scars a stability analysis of the palinuro flanks has been carried out to determine the sectors potentially prone to sliding in case of shallow volcanic earthquakes landslides are simulated by adopting a scenario based approach tsunamis induced by these mass movements and their propagation across the tyrrhenian sea are modeled results suggest that shallow earthquakes m 4 6 4 8 are able to destabilize the flanks of the volcanic chain generating slope failures sliding volumes in the order of 1 5 km3 and 2 4 km3 may induce waves as high as 1 5 and 6 m respectively along the peri tyrrhenian coast our results underline the need for further investigations on the stability of the submarine volcanoes of the tyrrhenian basin these volcanoes are still poorly known although their instability could trigger large tsunamis along the southern italy coastal sectors our recommendation is that multiparamertic monitoring networks on pvc and periodic oceanic cruises should be put into action and further that a systematic evaluation of the tsunami hazard related to possible sliding phenomena on the flanks of the tyrrhenian seamounts should be performed

western oceanus procellarum as seen by c1xs on chandrayaan 1 we present the analysis of an x ray fluorescence xrf observation of the western part of oceanus procellarum on the moon s nearside made by the chandrayaan 1 x ray spectrometer on 10th february 2009 through forward modelling of the x ray spectra we provide estimates of the mgo sio2 and al2o3 sio2 ratios for seven regions along the flare s ground track these results are combined with feo and tio2 contents derived from clementine multispectral reflectance data in order to investigate the compositional diversity of this region of the moon the ground track observed consists mainly of low ti basaltic units and the xrf data are largely consistent with this expectation however we obtain higher al2o3 sio2 ratios for these units than for most basalts in the apollo sample collection the widest compositional variation between the different lava flows is in wt feo content a footprint that occurs in a predominantly highland region immediately to the north of oceanus procellarum has a composition that is consistent with mixing between low ti mare basaltic and more feldspathic regoliths in contrast to some previous studies we find no evidence for systematic differences in surface composition as determined through x ray and gamma ray spectroscopy techniques

an aem tem study of weathering and diagenesis abert lake oregon ii diagenetic modification of the sedimentary assemblage abstract this paper compares the mineralogy and chemistry of clay minerals in sediments from various depths and positions in abert lake and surrounding playa with those of the weathered materials entering the lake in order to reveal the nature and extent of post depositional mineralogical modification analytical electron microscope aem data from individual clay particles reveal that each sample is comprised of a highly inhomogeneous smectite assemblage the thin clay flakes commonly less than 10 nm wide display a complete range in octahedral sheet compositions from nearly dioctahedral to nearly trioctahedral the very abundant mg rich lake smectites with an estimated composition k 0 29 al 0 23 mg 2 16 fe 0 30 si 3 80 al 0 20 o 10 oh 2 are not formed by weathering this confirms the importance of diagenetic mg uptake lattice fringe imaging failed to reveal distinct brucite like or vermiculite like layers suggesting that interstratifications of this type are rare or absent siliceous coatings on clay particles identified by silica excess in smectite analyses seem to favor topotactic overgrowth of stevensite rather than addition of brucite like layers to the dioctahedral nuclei the growth of k stevensite dilutes the al content of the crystal and thus the increasing diagenetic modification reduces rather than supplements its illite component smectite compositions within individual samples were highly variable yet source related characteristics such as the abundance of fe rich smectite were apparent little evidence for systematic k or mg enrichment with depth was identified in samples from depths of down to 16 feet below the sediment water interface the most magnesian assemblages are associated both with weathering sources of mg rich smectite and playa environments subjected to repeated wetting and drying cycles thus the observations suggest that clay compositions primarily reflect changes in lake levels brine composition and source characteristics rather than time and depth compaction effects other diagenetic reactions in the sediment include recrystallization of na rich silica gel and diatom fragments abundant submicron sized untwinned euhedral crystals of k feldspar are interpreted to be authigenic in origin

strontium 87 strontium 86 ratios as tracers in groundwater and surface waters in mono basin california the 87sr 86sr isotope ratios in spring waters in mono basin california are highly variable and reflect contact with different rock types whole rock 87sr 86sr ratios throughout the basin range between 0 7054 and 0 7281 ratios in surface water samples differ greatly between runoff from the mainly granitic sierra 0 7094 0 7097 and runoff from the volcanic regions 0 7054 0 7064 the ratio in mono lake water 0 7096 is similar to the ratios of streams from the sierra nevada springs close to the western shoreline have more radiogenic sr ratios 0 7092 0 7100 while those on the east side have ratios 0 7081 0 7088 indicative of a mixture of water from the volcanic terrain and mono lake thermal springs at the south side of the lake have 87sr 86sr ratios of 0 7081 0 7089 and might originate in paleozoic limestones at depth