partition coefficients for calcic plagioclase implications for archean anorthosites by the use of a multiple aliquot technique combined with statistical calculations to overcome effects of alteration and contamination we have determined partition coefficients d s for rare earth elements rees between natural high ca plagioclase megacrysts and their basaltic matrices some of the basalts that we investigated are shown experimentally to crystallize only high ca plagioclase over approximately a 20 30 c temperature interval below the liquidus the ree d s agree well with experimentally determined values and predict equilibrium melts for archean anorthosites that agree well with coeval basaltic flows and dikes furthermore the d s appear to be valid for both tholeiitic and alkali basalts over a range of mg numbers 34 58 and ree concentrations la from 3 50 ppm similarly calculated d s for co sc cr rb sr cs ba hf ta and th also predict equilibrium melts for anorthosites that agree reasonably well with coeval basaltic flows and dikes the apparent values for co sc and ta seem good to better than 50 whereas the standard deviations for rb and th are equal to their means making the d s of questionable value the others are useful probably to within a factor of 2 experimental studies of the d for total fe as feot indicate a value of about 04 at an oxygen fugacity slightly below that of the qfm buffer a by product of the feot experiments was the experimental d s for mgo tio2 and k2o which could be compared with the d s from natural assemblages from the d s that were determined we suggest that plagioclase megacrysts in the bad vermilion lake anorthosite were in equilibrium with melts having the composition of tholeiitic basalts at an oxygen fugacity slightly below the qfm buffer the predicted melts have an feot content of about 13 k2o of about 15 tio2 of about 1 3 a chondrite normalized ree pattern that is nearly flat at 10 to 20 chondrites with a slight depletion of lrees other incompatible trace elements at 10 to 20 chondrites and cr and co at 0 01 to 0 1 chondrites this range of compositions is essentially identical to the tholeiitic flows and dikes in archean greenstone belts we therefore suggest that the moderately fe rich tholeiites that are hosts to plagioclase megacrysts in greenstone belts form the parental melts for megacrysts which make up the bad vermilion lake anorthositic complex and probably other similar archean anorthositic complexes

trace element abundances and magnesium calcium and titanium isotopic compositions of grossite containing inclusions from the carbonaceous chondrite acfer 182 the carbonaceous chondrite acfer 182 contains ca al rich inclusions cais that differ from most cais in other meteorites many of them contain grossite caal4o7 whose modal abundance exceeds 30 vol in most of these cais grossite rich inclusions similar inclusions have been found only in the ch chondrite alh85085 and the cr chondrite acfer 059 el djouf 001 ion microprobe analyses of trace elements were made on nineteen cais from acfer 182 and two cais from acfer 059 el djouf 001 of al mg isotopes on eighteen acfer 182 and the two acfer 059 el djouf 001 inclusions and of calcium isotopes on ten acfer 182 inclusions on six of them also of titanium isotopes and one acfer 059 el djouf 001 inclusion trace element and isotopic signatures of grossite containing inclusions from acfer 182 resemble those of some inclusions from alh85085 volatility fractionated trace element abundance patterns ranging from ultrarefractory depleted similar to group ii pattern to volatile enhanced are predominant 17 cais including both inclusions from acfer 059 el djouf 001 two inclusions have ultrarefractory patterns one has a group iii pattern and one inclusion has a group iii related pattern similar to patterns found in hal type inclusions only one cai from acfer 182 but both inclusions from acfer 059 el djouf 001 have nonlinear excesses of 26mg corresponding to the initial 26al27al ratio of 5 10 5 none of the twenty inclusions has a significant intrinsic isotopic mass fractionation of mg titanium is normal in all analyzed cais and only small 48ca excesses 4 3 and 3 8 are present in two inclusions isotopes of both ca and ti show no significant intrinsic mass fractionations grossite containing inclusions from acfer 182 occur in different petrographic contexts in many cases petrographic characteristics are correlated with trace element abundances almost all inclusions studied in this work have a condensation history but no evidence for extensive evaporation processes is present many of the cais must have formed by direct gas solid condensation while some inclusions with clearly identifiable igneous textures formed from a refractory melt grossite whose formation was the subject of controversy in the past probably condensed from a reservoir with a higher than chondritic ca al ratio and depleted in the highly refractory trace elements or crystallized from a ca al rich melt the two ultrarefractory inclusions from acfer 182 have extremely high refractory trace element abundances sometimes exceeding 105 ci the lack of isotopic fractionation indicates a formation at very high temperatures by condensation rather than evaporation the lack of 26mg excesses in almost all inclusions from acfer 182 is best explained by heterogeneous distribution of 26al in the primitive solar nebula grossite rich inclusions having volatility fractionated ultrarefractory depleted trace element abundance patterns and lacking 26mg excesses could be the complement of platy hibonites placs from murchison with group iii or ultrarefractory patterns and likewise no 26mg excesses

partitioning of sr ba rb y and lree between plagioclase and peraluminous silicic magma trace element partition coefficients between plagioclase and coexisting glass matrix have been determined for twenty nine rhyodacite rhyolite samples from nine volcanic centers strontium partition coefficients form two clear positive trends when plotted against the an content of plagioclase one trend has a steep slope with d sr between 5 6 and 15 8 t1 whereas the other trend has a gentle slope with d sr between 1 2 and 7 6 t2 barium partition coefficients show similar patterns a steeply sloped trend is formed by samples with d ba between 1 6 and 8 8 and a gently sloped trend by samples with d ba 1 d sr and d ba in plagioclase correlate positively and both d sr and d ba correlate positively with temperature samples with large d sr and d ba are all from rocks with 1 wt cao these rocks are peraluminous and also have low total sr and ba partition coefficients for sr and ba are influenced by whole rock cao in high al rhyolite systems where these systems have low cao the opportunity increases for other divalent cations to enter the plagioclase structure strontium and ba will then enter the m position of plagioclase to balance the charge deficiency caused by the substitution of al for si because of the potent influence of whole rock composition on sr and ba partitioning for low cao rocks values of partition coefficients in petrogenetic modeling needs to be selected carefully

validation and verification of a numerical model for tsunami propagation and runup a robust numerical model to simulate propagation and runup of tsunami waves in the framework of non linear shallow water theory is developed the numerical code adopts a staggered leapfrog finite difference scheme to solve the shallow water equations formulated for depth averaged water fluxes in spherical coordinates a temporal position of the shoreline is calculated using a free surface moving boundary algorithm for large scale problems the developed algorithm is efficiently parallelized employing a domain decomposition technique the developed numerical model is benchmarked in an exhaustive series of tests suggested by noaa we conducted analytical and laboratory benchmarking for the cases of solitary wave runup on simple beaches runup of a solitary wave on a conically shaped island and the runup in the monai valley okushiri island japan during the 1993 hokkaido nansei oki tsunami in all conducted tests the calculated numerical solution is within an accuracy recommended by noaa standards we summarize results of numerical benchmarking of the model its strengths and limits with regards to reproduction of fundamental features of coastal inundation and also illustrate some possible improvements

a seasonal snow cover classification system for local to global applications abstract a new classification system for seasonal snow covers is proposed it has six classes tundra taiga alpine maritime prairie and ephemeral each class defined by a unique ensemble of textural and stratigraphic characteristics including the sequence of snow layers their thickness density and the crystal morphology and grain characteristics within each layer the classes can also be derived using a binary system of three climate variables wind precipitation and air temperature using this classification system the northern hemisphere distribution of the snow cover classes is mapped on a 0 5 lat 0 5 long grid these maps are compared to maps prepared from snow cover data collected in the former soviet union and alaska for these areas where both climatologically based and texturally based snow cover maps are available there is 62 and 90 agreement respectively five of the six snow classes are found in alaska from 1989 through 1992 hourly measurements consisting of 40 thermal and

laser ablation icpms study of trace element partitioning between plagioclase and basaltic melts an experimental approach plagioclase melt partition coefficients d for 34 trace elements at natural concentration levels were determined experimentally in a natural morb composition at atmospheric pressure using thin pt wire loops experiments were carried out at three tempera tures 1 220 1 200 and 1 180 c and at three different oxygen fugacities fo2 iw qfm air in order to assess the effect of fo2 on the partitioning of elements with multiple valence fe eu cr run products were analyzed by laser ablation icp ms most trace element ds increase slightly as temperature decreases except for dzr dfe deu and dcr that vary systematically with fo2 applying the lattice strain model to our data suggests the presence of fe 2 entirely in the octahedral

actinide chemistry in allende ca al rich inclusions the microscale distribution of u and th has been studied by fission track radiography in a set of ca al rich inclusions from the allende meteorite in the type b inclusions generally believed to have been melted the major phases melilite and fassaite are important actinide host phases with similar th u and roughly three times higher concentrations in melilite than fassaite significant enrichments are also found on grain boundaries and in some regions of alteration the distribution is not completely understood in terms of igneous partitioning and may also reflect incomplete assimilation of relict materials during melting on the rims of type b inclusions and throughout all other inclusions studied perovskite is the dominant actinide host phase however perovskite does not have a characteristic th u value measured ratios range from 1 4 to 12 both above and below the accepted solar system value of 3 8 overall neither alteration nor loss or gain of an actinide rich phase appears to have been an important th u fractionation mechanism volatility differences may be the dominant factor some results e g high th u for fluffy type a inclusions can be interpreted as resulting from incomplete incorporation of the more volatile u during a primary condensation stage but more complex interpretations are required for inclusions with low th u the th u and ree abundance patterns for the spinel plus perovskite rim suggest derivation of this rim by volatilization of interior material the time scale for this heating is required to be brief 10 4 sec but within this constraint spinel perovskite rim formation by several mechanisms deceleration heating passage through nebular hot spots differential sublimation or vaporization plus recondensation is possible

trace element partition coefficients for perovskite and hibonite in meteorite compositions the concentrations of 28 elements were measured using an ion microprobe in perovskite hibonite and coexisting melts in isothermal crystallization experiments on chemical compositions similar to those of compact type a cta ca al rich inclusions cai and to a hibonite glass microspherule the mineral melt partition coefficients d calculated from the measured concentrations for both minerals define reliable d values perovskite and hibonite d s have ranges of 10 2 for si to 20 for th and 3 10 3 for si to 8 for la respectively there are regular relationships between the ionic radius the valence of the trace element and the partition coefficients in perovskite and hibonite while there are differences in the d values between perovskite and hibonite they follow very similar trends with perovskite typically having d values that are 5 10 times higher for the same element perovskite and hibonite d s are almost identical for the divalent cations ba 0 02 and 0 03 respectively and sr 1 1 and 0 8 respectively in our experiments d mg for perovskite is low 0 03 when compared with the value for hibonite 0 5 mineral melt d s for the ree decrease continuously from d la 6 to d lu 0 03 in hibonite for perovskite ree d s increase slightly from d la 10 to d nd 15 and then decrease continuously to d lu 1 0 and d s for trivalent cations with smaller ionic radii than the ree are lower with d al 0 08 and d sc 0 15 lower than d cr 0 8 and d v 1 0 with the exception of d th and d si in perovskite and dsi in hibonite the d values for tetravalent cations and nb the only pentavalent element fall within the range of d s for the ree d th d u equals 3 in perovskite and 15 in hibonite our data can be applied to the genesis and evolution of hibonite in refractory meteorite inclusions for example low ba relative to other refractory elements such as hf zr la etc in hibonite has been observed in some hibonite bearing inclusions since d ba d hf d zr and d la in our experiments low ba may result from the incompatibility of ba in hibonite rather than the increased volatility of ba under oxidizing conditions during condensation in addition since d la d lu 50 for hibonite lree hree ratios of 1 in hibonite in some cta cai from leoville and allende are inconsistent with hibonite equilibrating with the melts that formed these inclusions and the hibonite is relict similar applications are possible with our perovskite partitioning data for example it is likely that high ree 500 1000 chondritic perovskite with th u of 3 4 that are found in the outer region of type b 1 cai have not been in equilibrium with the cai melt that contains 20 ch ree and a th u ratio of 3 and they are probably relics that survived the most recent partial melting event

thermal metamorphic history of a ca al rich inclusion constrained by high spatial resolution mg isotopic measurements with nanosims 50l abstract mg isotope data were collected by nanosims with high precision and high spatial resolution from a coarse grained type b ca al rich inclusion cai ek1 6 3 in the allende cv3 chondrite to evaluate the time scale of parent body thermal metamorphism the cai melilite and fassaite contain excesses of 26mg 26mg from the in situ decay of 26al the inferred initial ratio 26al 27al 0 5 8 2 4 10 5 is consistent with many previously reported coarse grained cais from cv chondrites e g macpherson et al 1995 however the anorthite has heterogeneous 26al 27al 0 ranging from 1 8 10 5 to 3 3 10 6 the 26al 26mg systematics within the anorthite is consistent with thermal diffusion of mg isotopes during metamorphism we also show that the heterogeneous distribution of 26mg in anorthite could have resulted from thermal diffusion of 26mg over a 0 6 0 8 ma time span mg diffusion thus may be responsible for the 26al 27al 0 heterogeneity within anorthite in cais

accretionary rims on inclusions in the allende meteorite abstract many inclusions in allende particularly those with irregular shapes are surrounded by a sequence of thin layers which differ from one another in texture mineralogy and mineral chemistry the layer underlying all others contains either ia pyroxene needles olivine clumps of hedenbergite and andradite ib olivine doughnuts or ic rectangular olivine crystals the next layer outward ii contains tiny

partitioning of strontium between plagioclase and melt a comment abstract the origin of the partition coefficient d for sr in plagioclase is ascribed by blundy and wood 1991 mainly to the chemistry of the crystal rather than that of the liquid however a major data set used to support this conclusion also demonstrates an important correlation of d with the augite content of the liquid one truth cannot be used to deny another from the same data set moreover it appears that d has a limiting value of 1 0 in the system an ab confirming the importance of liquid composition the data base of natural magmas said to justify the conclusions of the paper omits the important troctolitic and noritic low augite varieties for which the augite effect was specifically claimed and therefore cannot be used to discount the effect the data base is skewed toward silicic igneous rocks for which a high value of d is experimentally known the attempt to rationalize the data from the kiglapait intrusion by supposing the escape of low sr material ignores the evidence of the chilled margin which matches the sr budget of the cumulates and neglects to mention that the vented mass would have to be equal to that of the entire intrusion to account for the small variation in sr observed much work remains to be done but it is clear that the liquid plays a much more important role in this partitioning effect than allowed by the authors

field survey and numerical simulations a review of the 1998 papua new guinea tsunami the papua new guinea png tsunami of 1998 is re examined through a detailed review of the field survey as well as numerous numerical computations the discussion of the field survey explores a number of possible misinterpretations of the recorded data the survey data are then employed by a numerical model as a validation tool a boussinesq model and a nonlinear shallow water wave nlsw model are compared in order to quantify the effect of frequency dispersion on the landslide generated tsunami the numerical comparisons indicate that the nlsw model is a poor estimator of offshore wave heights however due to what appears to be depth limited breaking seaward of sissano spit both numerical models are in agreement in the prediction of maximum water elevations at the overtopped spit by comparing three different hot start initial profiles of the tsunami wave it is shown that the initial shape and orientation of the tsunami wave is secondary to the initial displaced water mass in regard to prediction of water elevations on the spit these numerical results indicate that agreement between numerical prediction of runup values with field recorded values at png cannot be used to validate either a nlsw tsunami propagation model or a specific landslide tsunami hot start initial condition finally with the use of traditional tsunami codes a new interpretation of the png runup measurements is presented

hydroxyl radical and nox production rates black carbon concentrations and light absorbing impurities in snow from field measurements of light penetration and nadir reflectivity of onshore and offshore coastal alaskan snow 1 photolytic production rates of no no2 and oh radicals in snow and the total absorption spectrum due to impurities in snowpack have been calculated for the ocean atmosphere sea ice snowpack oasis campaign during spring 2009 at barrow alaska the photolytic production rate and snowpack absorption cross sections were calculated from measurements of snowpack stratigraphy light penetration depths e folding depths nadir reflectivity 350 700 nm and uv broadband atmospheric radiation maximum nox fluxes calculated during the campaign owing to combined nitrate and nitrite photolysis were calculated as 72 nmol m 2 h 1 for the inland snowpack and 44 nmol m 2 h 1 for the snow on sea ice and snowpack around the barrow arctic research center barc depth integrated photochemical production rates of oh radicals were calculated giving maximum oh depth integrated production rates of 160 nmol m 2 h 1 for the inland snowpack and 110 120 nmol m 2 h 1 for the snow around barc and snow on sea ice light penetration e folding depths at a wavelength of 400 nm measured for snowpack in the vicinity of barrow and snow on sea ice are 9 cm and 14 cm for snow 15 km inland fitting scaled hulis humic like substances and black carbon absorption cross sections to the determined snow impurity absorption cross sections show a humic like component to snowpack absorption with typical concentrations of 1 2 1 5 gc g 1 estimates of black carbon concentrations for the four snowpacks are 40 to 70 ng g 1 for the terrestrial arctic snowpacks and 90 ng g 1 for snow on sea ice

developing an approximate tsunami hazard zone for areas with poor topographic coverage in alaska tsunamigenic earthquakes along the alaska aleutian megathrust pose a major threat to many rural coastal communities in alaska to mitigate the impact of tsunamis and minimize loss of life maximum potential runup and tsunami hazard zones need to be estimated despite a lack of the high resolution digital elevation models in this manuscript we present a methodology to approximate tsunami hazard zones in areas with poor topographic and bathymetric coverage to manage a trade off between the computational complexity and lack of quality data we develop three scenario earthquakes with the intention that one of them characterizes impacts of a credible worst case event we then apply a safety factor to account for the limited number of considered scenarios and a coarse resolution elevation model used to simulate water dynamics near the community the developed methodology is illustrated using a case study focused on the community of adak in the andreanof islands alaska to validate the proposed method we explore sensitivity of tsunami height with respect to the coseismic slip distribution and develop a comprehensive set of credible worst case scenarios for the community the tsunami hazard zone developed with the use of the safety factor is validated against high resolution modeling of potential inundation according to the set of worst case scenarios in a number of other coastal communities

a petrologic and ion microprobe study of a vigarano type b refractory inclusion evolution by multiple stages of alteration and melting abstract usnm 1623 8 is a type b vigarano inclusion 6 mm in diameter consisting of melilite ak12 72 fassaite 17 23 a12o3 5 17 tio2 anorthite and spinel secondary alteration is negligible and consists of diopside and sparse nepheline melilite is normally zoned and contains up to 0 35 wt na2o higher than generally seen in melilite from other refractory inclusions a strong correlation between akermanite content and na2o in 1623 8 melilite suggests that the na was present during igneous crystallization rather than introduced later by diffusion anorthite in 1623 8 is coarse grained but commonly has an irregular border with neighboring melilite crystals many spinel grains enclosed within anorthite have selvages of melilite around them which in places are continuous with melilite exterior to the anorthite the anorthite appears to be replacing melilite ion microprobe analyses of anorthite in 1623 8 show that there is no detectable excess 26mg in nine anorthite crystals that have 27 al 24 mg as high as 970 implying an upper limit of 26 al 27 al 0 7 one crystal was found that has excess 26mg consistent with 26 al 27 al 0 3 10 6 melilite in the outer portion of the inclusion 27 al 24 mg 2 7 11 5 contains excess 26mg that considered together with spinel and pyroxene defines an isochron consistent with the canonical early solar system value of 26 al 27 al 0 4 5 10 5 melilite near an anorthite 27 al 24 mg 1 6 5 9 has 26mg values in excess of those predicted from 26 al 27 al 0 4 5 10 5 presumably caused by redistribution of radiogenic 26mg from adjacent anorthite the high na2o inferred to have been present in the melt suggests that the precursor solids were na bearing such as for example refractory material having an allende like overprint of feldspathoid bearing secondary alteration the melting event must have been brief in order that not all of the na was vaporized during melting the isotopic composition of the anorthite relative to melilite indicates a subsequent much later after the decay of most or all 26a1 episode of partial melting or solidstate recrystallization that did not affect the al rich melilite but reset most of the anorthite and some mg rich melilite near anorthite because the inclusion is both rimmed and slightly altered this late resetting event appears to have been a nebular one an assumption of homogeneously distributed 26a1 in the regions of the nebula where the inclusion formed and was later modified implies a several millionyear interval between condensation of the precursors and final melting of 1623 8

experimental geochemistry of pu and sm and the thermodynamics of trace element partitioning the partitioning of pu and sm between diopside liquid and whitlockite liquid has been investigated experimentally to evaluate the geochemical coherence of pu and the light rees pu d sm d is 2 for both diopsidic pyroxene and whitlockite this small amount of fractionation would be decreased further if pu were compared to ce or nd our experimental results thus validate the suggestion that pu behaves as a lree during igneous processes in reducing environments our data and the data of ray et al 1983 indicate that temperature rather than melt composition is the most important control on elemental partitioning this is true even though we demonstrate that additions of only 1 2 wt of p2 o 5 to the diopside anorthite albite system change pu d cpx by a factor of two our data suggest that p 2o 5 in aluminosilicate melts serves as a complexing agent for the actinides and lanthanides

a response function approach for rapid far field tsunami forecasting predicting tsunami impacts at remote coasts largely relies on tsunami en route measurements in an open ocean in this work these measurements are used to generate instant tsunami predictions in deep water and near the coast the predictions are generated as a response or a combination of responses to one or more tsunameters with each response obtained as a convolution of real time tsunameter measurements and a pre computed pulse response function prf practical implementation of this method requires tables of prfs in a 3d parameter space earthquake location tsunameter forecasted site examples of hindcasting the 2010 chilean and the 2011 tohoku oki tsunamis along the us west coast and beyond demonstrated high accuracy of the suggested technology in application to trans pacific seismically generated tsunamis

the nature and origin of type b1 and b2 caal rich inclusions in the allende meteorite abstract the type b ca al rich inclusions in the allende carbonaceous chondrite form a continuous range from the mineralogically concentrically zoned b1 subtype to the unzoned b2 subtype these subtypes differ in i structure texture grain size and shape ii mineralogical proportions and compositions iii accessory mineralogy iv relative abundance of spinel framboids v rim layering vi major element chemistry and vii degree of secondary alteration these differences together with observations on the crystallization of synthetic melts suggest that the b1 inclusions crystallised relatively rapidly from molten parental material while b2 types crystallised relatively slowly close to the solidus from material that had not been completely melted the same data are used to construct an evaporative residue model for the origin of the parental type b materials in the model dust in the protosolar nebula was heated with removal of more volatile elements leaving completely melted type b1 residues at the highest temperatures and incompletely melted less highly evaporated type b2 residues at lower temperatures

experimental study of radium partitioning between anorthite and melt at 1 atm we present the first experimental radium mineral melt partitioning data specifically between anorthite and a cmas melt at atmospheric pressure 226 ra disequilibria are an important chronometer of recent magmatic activity ion microprobe measurement of coexisting anorthite and glass phases produces a molar d ra 0 040 0 006 and d ra d ba 0 24 0 05 at 1400 c our results indicate that lattice strain partitioning models fit the divalent ca sr ba ra partition coefficient data of this study well supporting previous work on crustal melting and magma chamber dynamics that has relied on such models to approximate radium partitioning behavior in the absence of experimentally determined values

the abundance and relative volatility of refractory trace elements in allende ca al rich inclusions implications for chemical and physical processes in the solar nebula abstract we have determined the relative volatility of lithophile refractory trace elements lrte in the solar nebula by first calculating 50 condensation temperatures for 26 lrte oxides assuming ideal solid solution in perovskite and where appropriate in hibonite and melilite the measured abundances of 25 lrte and six siderophile refractory trace elements in 97 group i 11 111 and v allende ca al rich inclusions cai s and in ultra refractory inclusions then are used to empirically modify lrte and refractory siderophile volatility sequences that are based on condensation temperatures alone sc is significantly less depleted in group ii allende cai s than are other lrte e g zr hf y that also have very high oxide condensation temperatures ba sr and eu three moderately volatile lrte are significantly more enriched in ca rich group ii and group iii allende cai s than they are in spinel rich varieties of these inclusions we explain these observations and several others by invoking dust fractionation s and crystal chemical and diffusion effects during the formation of allende cai s that overprinted volatility based on solid gas reactions alone for example we show that hibonite probably was not the carrier of the super refractory lithophile component that is missing from group ii allende inclusions anomalous hf depletions relative to zr and y that are common in group i iii and v allende cai s can be partly explained if anders and ebihara 38 overestimated the cosmic abundance of hf by approximately 10

efremovka 101 1 a cai with ultrarefractory ree patterns and enormous enrichments of sc zr and y in fassaite and perovskite inclusion 101 1 from the cv3 carbonaceous chondrite efremovka is a compact type a ca al rich inclusion cai highly enriched in ultrarefractory ur oxides it is the first complete cai with a ur rare earth element ree pattern found in a cv3 chondrite the inclusion is petrographically complex and was formed in a multistage process it consists of several lithologically unrelated units the core contains abundant y and zr perovskite sc and zr rich fassaite and metallic feni enclosed in melilite all mineral species except spinel in all lithological units exhibit the same basic ur ree pattern four different populations of perovskites are distinguished by different y zr ratios a few of the perovskites have y zr ratios similar to those obtained from crystal liquid fractionation experiments perovskites from the other three populations have either chondritic lower than chondritic y zr ratios or extremely low zr contents ca isotopic ratios differ among three perovskites from different populations demonstrating a variety of sources and formational processes most fassaites crystallized in situ through reaction between the cai liquid and preexisting perovskites this process induced redistribution of zr y sc and v between perovskite and fassaite thus overprinting the original abundances in perovskite fassaite reaction rims around feni metals are also encountered they are enriched in v which was gained from the metal through oxidation of v in metal during fassaite crystallization the relative abundances of zr y and sc in perovskites are complementary to the abundances of these elements in sc and zr fassaite indicating subsolidus partitioning of these elements between the two phases perovskites are enriched in y and depleted in sc and zr in comparison to fassaites the core contains two complete captured cais several sinuous fragments and fine grained polygonal refractory fragments an assemblage of andradite wollastonite hedenbergite and pure metallic iron is encoun tered as enclaves in the interior of some sinuous fragments metallic fe and wollastonite formed by reduction of preexisting andradite and hedenbergite nebular alteration products upon inclusion in the highly reduced cai melt numerous spinel clusters and framboids with varying v2o3 and cr2o3 concentrations are enclosed in individual melilite crystals in the host cai and captured cais the rim sequence of the host consists of six layers from the inside outward a feo poor spinel b sc bearing fassaite c al diopside d al and ca bearing olivine e pure diopside and f ca poor olivine like the constituents of the cai core all mineral layers of the rim sequence except spinel have the same ur ree pattern however the total ree abundances decrease systematically by 1 order of magnitude from layer 2 to layer 6 this feature strongly suggests formation of the rim sequence by successive condensation from a unique reservoir enriched in ur elements and excludes formation by flash heating petrography mineral chemistry ree refractory lithophile element abundances and ca isotopic compositions demonstrate the complex multistage formation history of a cai that on the surface looks like a regular type a inclusion copyright 2002 elsevier science ltd

evidence for shallow megathrust slip across the unalaska seismic gap during the great 1957 andreanof islands earthquake eastern aleutian islands alaska we reassess the slip distribution of the 1957 andreanof islands earthquake in the eastern part of the aftershock zone where published slip models infer little or no slip eyewitness reports tide gauge data and geological evidence for 9 23 m tsunami runups imply seafloor deformation offshore unalaska island in 1957 in contrast with previous studies that labeled the area a seismic gap here we simulate tsunami dynamics for a suite of deformation models that vary in depth and amount of megathrust slip tsunami simulations show that a shallow 5 15 km deep rupture with 20 m of slip most closely reproduces the 1957 dutch harbor marigram and nearby 18 m runup at sedanka island marked by stranded drift logs models that place slip 20 km predict waves that arrive too soon our results imply that shallow slip on the megathrust in 1957 extended east into an area that presently creeps

the run up of nonbreaking and breaking solitary waves abstract the run up of nonbreaking and breaking solitary waves on plane impermeable beaches is investigated with a lagrangian finite element boussinesq wave model wave breaking is parameterized with an artificial viscosity diffusion term in the momentum equation and bottom friction is modelled with a term quadratic in the horizontal fluid velocity comparisons are presented with laboratory data of maximum run up shoreline motion and spatial profiles of near shore free surface elevation for both steep 20 and gradual 2 88 slopes for the steep slope only waves which do not break on run up are considered and excellent agreement is obtained with the laboratory data for the gradual slope wave shoaling breaking bore formation and subsequent collapse at the shoreline are predicted well by the model although the breaking algorithm does not attempt to model the details of the turbulent flow in the breaking region the backwash bore is also modelled reasonably well although it persists longer in the numerical computations than in the laboratory data it is shown that the inclusion of nonhydrostatic effects reduces the tendency of waves to break and improves the agreement of the numerical results with the laboratory run up data this allows higher amplitude waves to be modelled and larger propagation distances to be treated without the need to limit the wave steepness with artificial dissipation

melt solidification and late stage evaporation in the evolution of a fun inclusion from the vigarano c3v chondrite vigarano 1623 5 is a forsterite bearing refractory inclusion in which oxygen magnesium and silicon show large degrees of mass dependent isotopic fractionation the core of 1623 5 consists of forsteritic olivine fassaite melilite ak89 and spinel all of which show isotopic mass fractionation averaging 30 6 amu for magnesium and 10 0 amu for silicon it is enclosed in a mantle consisting of aluminous melilite ak16 60 spinel perovskite and hibonite hibonite and spinel in the mantle are enriched in heavy isotopes of magnesium by 8 15 amu relative to the core 1623 5 originally formed by solidification of a magnesium rich melt the endemic isotopic mass fractionation may have been caused by evaporation of that melt or may reflect an earlier evaporation event affecting the reservoir from which the interior of 1623 5 formed later flash remelting of the outer part of the core and volatilization of sio2 and mgo from the melt so produced caused formation of a mantle that is in isotopic and petrologic disequilibrium with the core

runup of solitary waves on a circular island this is a study of the interactions of solitary waves climbing up a circular island a series of large scale laboratory experiments with waves of different incident height to depth ratios and different crest lengths is described detailed two dimensional run up height measurements and time histories of surface elevations around the island are presented a numerical model based on the two dimensional shallow water wave equations including runup calculations was developed numerical model predictions agreed very well with the laboratory data and the model was used to study wave trapping and the effect of slope under certain conditions enhanced runup and wave trapping on the lee side of the island were observed suggesting a possible explanation for the devastation reported by field surveys in babi island off flores indonesia and in okushiri island japan

combined effects of tectonic and landslide generated tsunami runup at seward alaska during the mw 9 2 1964 earthquake we apply a recently developed and validated numerical model of tsunami propagation and runup to study the inundation of resurrection bay and the town of seward by the 1964 alaska tsunami seward was hit by both tectonic and landslide generated tsunami waves during the m rm w 9 2 1964 megathrust earthquake the earthquake triggered a series of submarine mass failures around the fjord which resulted in landsliding of part of the coastline into the water along with the loss of the port facilities these submarine mass failures generated local waves in the bay within 5 min of the beginning of strong ground motion recent studies estimate the total volume of underwater slide material that moved in resurrection bay to be about 211 million m3 haeussler et al in submarine mass movements and their consequences pp 269 278 2007 the first tectonic tsunami wave arrived in resurrection bay about 30 min after the main shock and was about the same height as the local landslide generated waves our previous numerical study which focused only on the local landslide generated waves in resurrection bay demonstrated that they were produced by a number of different slope failures and estimated relative contributions of different submarine slide complexes into tsunami amplitudes suleimani et al in pure appl geophys 166 131 152 2009 this work extends the previous study by calculating tsunami inundation in resurrection bay caused by the combined impact of landslide generated waves and the tectonic tsunami and comparing the composite inundation area with observations to simulate landslide tsunami runup in seward we use a viscous slide model of jiang and leblond j phys oceanogr 24 3 559 572 1994 coupled with nonlinear shallow water equations the input data set includes a high resolution multibeam bathymetry and lidar topography grid of resurrection bay and an initial thickness of slide material based on pre and post earthquake bathymetry difference maps for simulation of tectonic tsunami runup we derive the 1964 coseismic deformations from detailed slip distribution in the rupture area and use them as an initial condition for propagation of the tectonic tsunami the numerical model employs nonlinear shallow water equations formulated for depth averaged water fluxes and calculates a temporal position of the shoreline using a free surface moving boundary algorithm we find that the calculated tsunami runup in seward caused first by local submarine landslide generated waves and later by a tectonic tsunami is in good agreement with observations of the inundation zone the analysis of inundation caused by two different tsunami sources improves our understanding of their relative contributions and supports tsunami risk mitigation in south central alaska the record of the 1964 earthquake tsunami and submarine landslides combined with the high resolution topography and bathymetry of resurrection bay make it an ideal location for studying tectonic tsunamis in coastal regions susceptible to underwater landslides

chemical composition of hal an isotopically unusual allende inclusion thirty seven major minor and trace elements were determined by inaa and rnaa in samples of hibonite black rim and portions of friable rim from an unusual allende inclusion hal the peculiar isotopic mineralogical and textural properties of hal are accompanied by very unusual trace element abundances the most striking feature of the chemistry is the virtual absence of ce from an inclusion otherwise highly enriched in ree compared to cl chondrites hal is also depleted in sr ba u v ru os and ir relative to other refractory elements of the lithophile elements determined which are normally considered to be refractory in a gas of solar composition sr ba ce u and v are the most volatile in oxidizing gases the distribution of ree between hibonite and rims seems to have been established when hibonite and other refractory minerals were removed at slightly different temperatures from a hot oxidizing gas in which they previously coexisted as separate grains on the basis of hal s chemical and isotopic composition possible locations for the chemical and mass dependent isotopic fractionation are in ejecta from the low temperature helium burning zone of a supernova and in the locally oxidizing environment generated by evaporation of interstellar grains of near chondritic chemical composition

magmatic evolution of lunar highland rocks estimated from trace elements in plagioclase a new bulk silicate moon model with sub chondritic ti ba sr ba and sr al ratios abstract the compositions of host magmas of ferroan anorthosites fan host magmas were estimated from secondary ion mass spectrometry analyses of plagioclase in lunar highland rocks the evolution of the magmas was investigated by considering phase relations based on the melts algorithm and by re examining partition coefficients for trace elements between plagioclase and melts data little affected by post magmatic processes were selected by using plagioclase with relatively primitive sc and co contents the fan host magma contained 90 174 ppm sr 40 119 ppm ba and 0 5 1 3 tio2 and had sub chondritic sr ba and ti ba ratios it is difficult to account for the formation of fan host magma on the basis of magma evolution processes of previously proposed bulk silicate moon models with chondritic ratios for refractory elements at global scale therefore the source of the fan host magma must have had primordial sub chondritic sr ba and ti ba ratios the fan host magmas were consistent in refractory elements with the estimated host mafic magma for feldspathic crust based on lunar meteorites and some very low ti mare rocks from lunar meteorites here we propose an alternative bulk silicate moon model the cbsm model which is enriched in crustal components of proto bodies relative to the present whole earth moon system

land water boundary treatment for a tsunami model with dimensional splitting the method of splitting tsunamis most model adapted by national oceanic and atmospheric administration noaa for tsunami forecasting operations is praised for its computational efficiency associated with the use of splitting technique it will be shown however that splitting the computations between x and y directions results in specific sensitivity to the treatment of land water boundary slight modification to the reflective boundary condition in most caused an appreciable difference in the results this is demonstrated with simulations of the tohoku 2011 tsunami from the source earthquake to monterey bay california and in southeast alaska followed by comparison with tide gage records in the first case the better representation of later waves reflected from the coasts by the modified model in a pacific wide simulation resulted in twice as long match between simulated and observed tsunami time histories at monterey gage in the second case the modified model was able to propagate the tsunami wave and approach gage records at locations within narrow channels juneau ketchikan to where most had difficulty propagating the wave the modification was extended to include inundation computation the resulting inundation algorithm cliffs has been tested with the complete set of noaa recommended benchmark problems focused on inundation the solutions are compared to the most solutions obtained with the version of the most model benchmarked for the national tsunami hazard mitigation program in 2011 in two tests cliffs and most results are very close and in another two tests the results are somewhat different very different regimes of generation disposal of water by cliffs and most inundation algorithms which supposedly affected the benchmarking results have been discussed

physically based modeling of atmosphere to snow to firn transfer of h2o2 at south pole quantitative interpretation of ice core chemical records requires a detailed understanding of the transfer processes that relate atmospheric concentrations to those in the snow firn and ice a unique 2 year set of year round surface snow samples at south pole and snow pits with associated accumulation histories were used to test a physically based model for atmosphere to firn transfer of h2o2 the model which extends our previous transfer modeling at south pole into the snowpack is based on the advection dispersion equation and spherical diffusion within representative snow grains required physical characteristics of the snowpack such as snow temperature and ventilation were estimated independently using established physical models the surface snow samples and related model simulations show that there is a repeatable annual cycle in h2o2 in the surface snow at south pole it peaks in early spring and surface snow concentration is primarily determined by atmospheric concentration and temperature with some dependence on grain size the snow pits and associated model simulations point out the importance of accumulation timing and annual accumulation rate in understanding the deposition and preservation of h2o2 and 18o at south pole long term snowpack simulations suggest that the firn continues to lose h2o2 to the atmosphere for at least 10 12 years 3 m after burial at current south pole temperatures and accumulation rates

trace element disequilibria and magnesium isotope heterogeneity in 3655a evidence for a complex multi stage evolution of a typical allende type b1 cai we used the panurge ion microprobe to measure concentrations of the rare earth elements rees ba hf and sr in melilite clinopyroxene plagioclase and perovskite and mg isotopes in plagioclase spinel melilite fassaite hibonite grossular and monticellite from the allende type b1 calcium aluminum rich inclusion cai usnm 3655a the distribution and concentration of ba and the ree in melilite from the melilite rich mantle of 3655a are unlike those predicted from melilite melt ree partitioning experiments for closed system crystal fractionation ree concentrations are lower than expected in the first crystallized gehlenitic melilite increase rapidly to higher than expected concentrations in melilite with intermediate akermanite contents ak30 ak40 and decrease as expected only during the late stage of mantle crystallization barium concentrations in melilite are 10 50 times those expected and the lree hree ratio increases continuously rather than remaining constant the unexpected distribution of trace elements in melilite reflects a progressive enrichment of trace elements in the melt during the early stages of crystallization a partial explanation for this observation is the dissolution of precursor perovskite that contained half or more of the total ree budget of the inclusion in addition there are large trace element enrichments adjacent to included spinel in melilite and similar but smaller enrichments adjacent to spinet in clinopyroxene these enrichments are consistent with the existence of trace element enriched boundary layers at the mineral melt interfaces the fact that kinetic processes partially control trace element abundances and distributions suggests rapid cooling during crystallization of the melilite rich mantle similar trace element signatures are ubiquitous in type b1 cai suggesting that each experienced a similar thermal history the mg isotope record of 3655a is distinguished by four salient features 1 large 26 mg excesses correlated with the respective ai mg ratios in plagioclase melilite and hibonite 2 f mg the mass dependent fractionation of mg is positive with enrichment of the heavier mg isotopes in all primary phases 3 a heterogeneous distribution of f mg values with f mg in melilite systematically greater than in either spinel or fassaite and 4 isotopically normal mg in the secondary alteration phases grossular and monticellite the occurrence of 26 mg the decay product of 26 al in anorthite implies early formation of 3655a while 26 al was extant at nearly the canonical solar system value of 5 10 5 the trace element and mg isotope heterogeneities suggest a formation scenario for 3655a which includes 1 flash heating to partially melt a solid precursor 2 rapid cooling to allow survival of relict phases 3 diffusive exchange of mg between melilite and a nebular reservoir and 4 alteration at low temperature although this model explains most of the trace element and isotopic characteristics of 3655a and other type bi cais it does not provide an explanation for the rapid change of lree hree ratios of melilite during crystallization

source models for the 1993 hokkaido nansei oki earthquake tsunami a source model for the 1993 hokkaido nansei oki tsunami must satisfy certain conditions such conditions are presented in this paper and two methods are used to determine the best source model for this event a trial and error method selects dcrc 17a as the best among 24 different models this model has three fault planes dipping westward to reproduce well the tide gauge records at two locations an inversion analysis is used to modify the dislocation of dcrc 17a

propagation and amplification of tsunamis at coastal boundaries when tsunamis hit a coastal area they often cause substantial damage and loss of life at locations otherwise well protected from normal even severe wind generated waves an example of such a catastrophe took place on 12 december 1992 when an earthquake of magnitude ms 7 5 occurred in the eastern region of flores island indonesia1 2 one of the areas hardest hit by the resulting tsunamis was babi a small coastal island two villages on the island were completely destroyed even though both were located in sheltered areas where wave conditions are normally calm here we describe the results of numerical and laboratory experiments that show how unlike wind generated waves tsunamis are capable of penetrating into sheltered coastal areas without significantly losing their energy for the case of babi island the original tsunami wave was split into two with one wave propagating around each side of the island the two waves met in the sheltered region and the subsequent amplification of wave amplitude resulted in the destructive flow onto the beach

crystal chemical effects on the partitioning of trace elements between mineral and melt an experimental study of melilite with applications to refractory inclusions from carbonaceous chondrites the partitioning behavior of the trace elements be sc ba la ce and tm between melilite and liquid has been determined using stepwise integration of a rayleigh fractionation equation for ion microprobe analyses of synthetic zoned melilite crystals distribution coefficients between melilite and liquid d mel l i were determined over the entire range of melilite spinel crystallization for one bulk composition corresponding to that of an average type b inclusion from the allende c3v carbonaceous chondrite beryllium is incompatible in gehlenitic meliliters e g d mel l b e 0 5 for x ak 0 3 but compatible in akermanitic melilites e g d mel l b e 1 9 for x ak 0 75 barium d mel l b a 0 04 0 05 sc d mel l s c 0 01 0 02 la d mel l l 0 07 0 29 ce d mel l c e 0 05 0 21 and tm d mel l t m 0 03 0 14 are all incompatible in melilites in the range ak25 ak75 variations in d mel l i as a function of x ak are explicable in terms of a simple thermodynamic treatment of trace element partitioning based on crystal chemical considerations characteristic trace element zoning patterns are predicted for early crystallizing melilite from meliliterich type b inclusions for example concentrations of the rees in melilite should continually decrease with increasing degrees of crystallization opposite the behavior normally expected of an incompatible element concentrations of be should rise with increasing degrees of crystallization even when the element is compatible again opposite the behavior normally expected of compatible elements in general zoning patterns of trace elements in melilite from type b inclusions are consistent with those predicted for fractional crystallization from a melt in a closed system trace element zoning patterns in meteoritic melilite crystals constrain the origin and thermal histories of ca al rich inclusions from carbonaceous chondrites

the identification of group ii inclusions in carbonaceous chondrites by electron probe microanalysis of perovskite abstract group ii ca al rich inclusions cais which are relatively depleted in super refractory lithophile trace elements sre e g er lu sc zr y hf formed from nebular or interstellar reservoirs depleted in sre enriched dust their unusual chemistry preserves a record of widespread but incompletely understood fractionation processes in the primitive solar nebula we demonstrate that because group ii inclusions have anomalously high ti sre ratios they can be identified by electron probe microanalysis epma of perovskite a host for ti and several sre perovskites in group ii allende cais generally contain 0 25 wt zro2 the y content of perovskite also can be used to identify group ii inclusions by this technique inclusions with zr y poor perovskite in principle need not be depleted in sre if they contain other phases suitably enriched in sre but an analysis of sre carriers in allende inclusions and bulk compositions of cais shows that in practice this factor does not invalidate the epma technique for identifying group ii cais epma of perovskite in eight allende inclusions demonstrates that 75 of fine grained cais i e spinel rich complex cais are group ii inclusions in agreement with their abundance as determined by bulk trace element analyses of 24 cais a spinel rich nodule in a rimmed olivine aggregate contains zr y poor perovskites evidence that similar nodules which occur in 25 of olivine rich allende inclusions are the group ii ree carrier in olivine rich inclusions that have highly fractionated trace element patterns i e fractionated aoas

laboratory experiments of tsunami runup on a circular island laboratory experiments of a 7 2 m diameter conical island were conducted to study three dimensional tsunami runup the 62 5 cm tall island had 1 on 4 side slopes and was positioned in the center of a 30 m wide by 25 m long flat bottom basin solitary waves with height to depth ratios ranging from 0 05 to 0 20 and source lengths ranging from 0 30 to 7 14 island diameters were tested in water depths of 32 and 42 cm twenty seven capacitance wave gages were used to measure surface wave elevations at incident and four radial transects on the island slope maximum vertical runup measurements were made at 20 locations around the perimeter of the island using rod and transit a new runup gage was located on the back or lee side of the island to record runup time series

a chemical and isotopic study of hibonite rich refractory inclusions in primitive meteorites the ion microprobe has been used to determine the concentrations of a number of trace elements including all 14 stable rare earth elements and the isotopic compositions of ca and mg in seven hibonite rich refractory inclusions hibonite in every inclusion analyzed shows the effect of ree partitioning with other solid or liquid phases in which hibonite is enriched in light over heavy ree compared to other coexisting phases this partitioning causes cl chondritenormalized enrichments to drop by factors of 4 to 22 from lanthanum to lutetium fractionations due to gas solid partitioning of ree are sometimes superimposed on the pattern produced by partitioning between condensed phases two inclusions hal and dh h1 show evidence for formation in extremely oxidizing environments and their ca is mass fractionated in favor of the heavy isotopes by 7 and 12 amu respectively two corundum hibonite inclusions show evidence of extremely high temperature gas solid fractionation such that the more volatile light ree are depleted as a group relative to the more refractory heavy ree these inclusions both have ca that is mass fractionated in favor of the light isotopes hibonite preserves the largest nuclear isotope anomalies in ti found to date faheyet al 1985a hintonel al 1987b but there does not seem to be a simple relationship between chemical composition isotopic mass fractionation and the sign and magnitude of nuclear isotopic anomalies in hibonite rich inclusions one possibility for producing a variety of chemical compositions and degrees of mass fractionation while preserving nuclear isotope anomalies is by multiple cycles of condensation and evaporation in a turbulent protoplanetary accretion disk morfill 1983 morfill and r n clayton 1986a b these cycles could also occur in a presolar nebula with large non axisymmetric temperature and pressure distributions boss 1988 nuclear anomalies are most likely to be preserved in hibonite because hibonite is the most refractory major phase to occur commonly in meteorites

the formation of rims on calcium aluminum rich inclusions step i flash heating abstract wark lovering rims of six calcium aluminum rich inclusions cais representing the main cai types and groups in allende efremovka and vigarano were microsurgically separated and analysed by neutron activation analysis naa all the rims have similar 4x enrichments relative to the interiors of highly refractory lithophile and siderophile elements the naa results are confirmed by ion microprobe and scanning electron microscope sem analyses of rim perovskites and rim metal grains less refractory eu yb v sr ca and ni are less enriched in the rims the refractory element patterns in the rims parallel the patterns in the outer parts of the cais in particular the rims on type b1 cais have the igneously fractionated rare earth element ree pattern of the melilite mantle below the rim and not the ree pattern of the bulk cai proving that the refractory elements in the rims were derived from the outer mantle and were not condensates onto the cais the refractory elements were enriched in an al2o3 rich residue 50 m thick after the most volatile 80 of the outermost 200 m of each cai had been volatilized including much mg si and ca some volatilization occurred below the rim and created refractory partial melts that crystallized hibonite and gehlenitic melilite the required flash heating probably exceeded 2000 c but for only a few seconds in order to melt only the outer cai and to unselectively volatilize slow diffusing o isotopes which show no mass fractionation in the rim the volatilization did however produce heavy mass fractionated mg in rims in some cais this was later obscured when normal mg diffused in from accreted olivine grains at relatively high temperature not the lower temperature meteorite metamorphism and created the 50 m set of monomineralic rim layers of pyroxene melilite and spinel

experimental studies of trace element partitioning in ca al rich compositions anorthite and perovskite using electron probe and ion probe techniques experimental crystal liquid partition coefficients d have been measured in meteoritic ca al rich inclusion cai compositions for mg zr y and rees in anorthite and perovskite partitioning data for ti in anorthite and al in perovskite are also reported where cross comparisons are possible between electron and ion probe data agreement is good concentration variations in anorthite for many elements are beyond what can be explained by fractional crystallization but show well defined interelement correlations which could reflect the temperature dependence of the d values or could result from liquid boundary layers for anorthite our d values for rees are lower and they decrease more rapidly with decreasing ionic radius than most in the literature most of the older ree d patterns for plagioclase in the literature are too flat because of insufficient purity of mineral separates or because of analytical problems new ion probe data for minor and trace elements in anorthite from type b cais permit detailed comparisons with fractional crystallization models based on the measured d values for most comparisons models and observations do not agree for amounts of crystallization less than 90 it is possible that anorthite does not appear until after 95 crystallization compared to about 40 which would be expected from isothermal equilibrium crystallization experiments the lrees are highly compatible elements in perovskite but d values drop sharply for the hrees y and zr d values for rees increase strongly from air to highly reducing conditions as coupled ree ti 3 substitutions become possible model calculations show that ree patterns in igneous perovskites from cais will reflect the d pattern and the models can explain some ree patterns from compact type a cais however there are other sets of trace element data for perovskite in cais that cannot easily be explained by igneous processes

the importance of considering depth resolved photochemistry in snow a radiative transfer study of no2 and oh production in ny alesund svalbard snowpacks solar visible radiation can penetrate 2 30 cm e folding depth into snowpacks and photolyse nitrate anions and hydrogen peroxide contained in the snow photolysis rate coefficients j for no3 and h2o2 photolysis are presented for a melting and a fresh snowpack at ny alesund svalbard calculations of a transfer velocities and molecular fluxes of gaseous no2 from the snowpack and b depth integrated production rates of oh radicals within the snowpack are presented the results show the importance of considering the depth dependence i e not just the snow surface when modelling snowpack photochemistry neglecting photochemistry under the snow surface can result in an apparent larger molecular flux of no2 from no3 photolysis than the melting snowpack however when the depth resolved molecular fluxes of no2 within the snowpack are calculated a larger no2 flux may be apparent in the melting snowpack than the fresh snowpack for solar zenith angles of 608 7 08 and 808 the modelled molecular fluxes of no2 from fresh snowpack are 11 6 5 6 and 1 7 nmol m 2 h 1 respectively and those for melting snowpack are 19 7 9 1 and 2 9 nmol m 2 h 1 respectively

note on the 1964 alaska tsunami generation by horizontal displacements of ocean bottom numerical modeling of the runup in chenega cove alaska a numerical model of the wave dynamics in chenega cove alaska during the historic m w 9 2 megathrust earthquake is presented during the earthquake locally generated waves of unknown origin were identified at the village of chenega located in the western part of prince william sound the waves appeared shortly after the shaking began and swept away most of the buildings while the shaking continued we model the tectonic tsunami in chenega cove assuming different tsunami generation processes modeled results are compared with eyewitness reports and an observed runup results of the numerical experiments let us claim the importance of including both vertical and horizontal displacement into the 1964 tsunami generation process we also present an explanation for the fact that arrivals of later waves in chenega were unnoticed

a unique ultrarefractory inclusion from the murchison meteorite through freeze thaw disaggregation of the murchison meteorite we have recovered a refractory inclusion hib 11 that is unique in terms of its texture mineral compositions and bulk composition it consists of anhedral y rich 1 6 wt y2o3 perovskite and lathlike spinel grains enclosed in a matrix of fine grained sc rich 10 5 wt sc2o3 avg ti rich 12 6 wt tio2 avg reporting all ti as tio2 clinopyroxene the chondrite normalized rare earth element ree pattern is complex with light ree lree at 10 c1 abundances increasing from gd through ho the latter at 104 c1 decreasing through yb at 200 c1 and lu at 400 c1 the pattern reflects several stages of high temperature volatility fractionation removal of lu and er from the source gas in the first condensation event was followed by partial to complete removal of the somewhat less refractory heavy ree gd through ho in the hib 11 precursors by condensation from the fractionated residual gas in a second event both of these events probably reflect condensation of ree into zro2 or a mixed zr sc ti y oxide at temperatures too high for hibonite stability a second lower temperature component which was subsequently added had fractionated nd poor ce rich lree abundances that resulted from condensation from a gas that had undergone prior removal of the more refractory lree resulting in enrichment in ce and the most volatile ree eu and yb the aggregate was then melted and quickly cooled forming a fine grained spherule this is the first reported inclusion in which the two most refractory ree lu and er are strongly fractionated from the other ree an absence of mass fractionation among the ti isotopes indicates that hib 11 is not an evaporative residue implying that volatility fractionation of trace elements took place during condensation the fact that the two most refractory heavy ree could be separated from the other only slightly less refractory heavy ree suggests that a wide variety of ree patterns is possible and that ultrarefractory inclusions with other unusual ree patterns important recorders of nebular condensation may yet be discovered

crystallization sequences of ca al rich inclusions from allende an experimental study the equilibrium crystallization sequence at 1 atmosphere in air of a melt corresponding in composition to the average composition of type b ca al rich inclusions from the allende meteorite is spinel 1550 c melilite 1400 c ak22 anorthite 1260 c ti al rich clinopyroxene 1230 c ti fassaite the melilite becomes increasingly akermanitic with decreasing temperature the pyroxene is similar in composition to fassaites from type b inclusions preliminary results suggest that the crystallization sequence is similar at oxygen fugacities near the iron wustite buffer the results of these experiments have been integrated with available phase equilibrium data in the system cao mgo al 2o 3 sio 2tio 2 and a phase diagram for predicting the crystallization sequences of liquids with compositions of coarse grained ca al rich inclusions has been developed available bulk compositions of coarse grained inclusions form a well defined trend in terms of major elements extending from type a and bl inclusions near the spinel melilite join to more pyroxene rich type b2 inclusions the trend deviates from the expected sequence of solid condensates from a nebular gas at p 10 3 atm if pure diopside is assumed to be the clinopyroxene that condenses the type a b1 end of the trend is similar in composition to calculated equilibrium condensates at 1202 1227 c and the trend as a whole parallels the sequence of condensates expected from diopside condensation at 1170 c the trend is consistent to first order with the condensation of solid ti rich fassaite in place of pure diopside at higher temperatures than those at which pure diopside is predicted to condense partially molten condensates may be likely in this case or if the nebular pressure is higher than 10 3 atm

experimental determination of ra mineral melt partitioning for feldspars and 226ra disequilibrium crystallization ages of plagioclase and alkali feldspar radium and other trace element partition coefficients have been experimentally determined for plagioclase and alkali feldspar in equilibrium with silicate melts in anorthitic plagioclase alkalis e g na k rb cs and the heavy earth alkalis e g ba ra are incompatibles in albitic plagioclase na is compatible whereas ca and sr are always compatible in plagioclase draplagioclase melt was determined to be 0 017 0 006 an91 0 025 0 009 an81 and 0 47 0 08 an34 for three different an contents the ratio dra dba increasing with decreasing an component in alkali feldspar k rb ba ra and sr are compatible whereas na cs and ca are incompatible draalkali feldspar melt was determined to 2 54 0 04 for a or75ab21an4 composition the ratio dra dba is 0 55 0 01 for plagioclase dra and xan are related as rt lndra kj mol 52 54 5 75 xan 4 25 1 51 and dra dba exp 9 47 6 21 xan 13 66 1 52 rt kj mol allowing calculation of dra from the an content of magmatic plagioclase for alkali feldspar we propose the equation dra dba exp 16 06 0 58 15 52 0 67 xor rt kj mol the experimentally determined partition coefficients are then used to recalculate th ra ba model ages leading to generally shorter feldspar residence times the variations encompass 20 to 90 shorter crystallization ages with respect to the originally calculated ones in two cases feldspar crystallization ages increase slightly for several cases the measured plagioclase and melt have either never been in equilibrium or the th ra ba system has been disturbed after crystallization

the runup of solitary waves this is a study of the runup of solitary waves on plane beaches an approximate theory is presented for non breaking waves and an asymptotic result is derived for the maximum runup of solitary waves a series of laboratory experiments is described to support the theory it is shown that the linear theory predicts the maximum runup satisfactorily and that the nonlinear theory describes the climb of solitary waves equally well different runup regimes are found to exist for the runup of breaking and non breaking waves a breaking criterion is derived for determining whether a solitary wave will break as it climbs up a sloping beach and a different criterion is shown to apply for determining whether a wave will break during rundown these results are used to explain some of the existing empirical runup relationships

origin of compact type a refractory inclusions from cv3 carbonaceous chondrites compact type a cta inclusions are one of the major types of coarse grained refractory inclusions found in carbonaceous chondrites they have not been studied in a systematic fashion leading to some uncertainties and unproven assumptions about their origin to address this situation we studied a total of eight ctas from allende efremovka and axtell by scanning electron microscopic and electron and ion microprobe techniques these inclusions are very melilite rich ranging from 60 vol to nearly monomineralic also present are mg al spinel 5 20 perovskite trace 3 and in some samples ti rich 17 wt tio2tot fassaite trace 20 and rhonite 1 melilite compositions are mostly between ak15 and ak40 chondrite normalized ree abundance patterns for melilite flat at 10 ci with positive eu anomalies and fassaite slight hree enrichment relative to lree and negative eu anomalies are like those for their counterparts in once molten type b inclusions the patterns for rhonite have positive slopes from la through lu and abundances 10 ci for la and 35 60 ci for lu features of ctas that suggest that they were once molten include rounded inclusion shapes positively correlated sc and v abundances in fassaite radially oriented melilite laths at inclusion rims and the distribution of trace elements among the phases fractional crystallization models show that with one exception the ree contents of perovskite and fassaite arose by crystallization of these phases from late residual liquids that would have resulted from prior crystallization of the observed proportions of melilite and spinel from liquids having the bulk compositions of the inclusions one allende cta ts32 however has several features irregular shape reversely zoned melilite fassaite ree contents that are not readily explained by crystallization from a melt this inclusion may have undergone little melting and may be dominated by relict grains

fassaite composition trends during crystallization of allende type b refractory inclusion melts fassaite is a major phase in type b refractory inclusions and its wide compositional variability makes it an excellent recorder of crystallization induced changes in liquid composition traverses across zoned crystals with electron and ion microprobes show that ti v sc zr and hf decrease from core to rim while mg si rees and other trace elements increase fassaite liquid distribution coefficients derived from the compositions of early fassaite and calculated parent liquid compositions are higher than previously reported fassaite ds e g 0 2 0 8 vs 0 08 0 5 for the trivalent rees possibly due to the high ti and al contents of the fassaite we analyzed log log plots of concentrations of elements vs those of sc give linear relationships with slopes of dixl l 1 dscxl l 1 where dixl l is the bulk crystal liquid distribution coefficient for element i from this relationship we derive effective fassaite liquid ds of 2 8 for sc 1 5 for hf 1 1 for zr 0 52 for y 0 34 for ta 0 29 for nb and 0 31 0 48 for trivalent rees the effective ds are applicable to fassaite crystallizing from melts having the compositions and thermal histories of allende type b refractory inclusions and incorporate any equilibrium and kinetic effects that modify ds during the course of crystallization observed fassaite ree contents can be reproduced by a fractional crystallization model in which the effective ds are used ti3 is more compatible in fassaite than ti4 and without equilibration of the residual liquid with an external reducing gas ti3 titot ratios where titot ti3 ti4 should decrease from core to rim in fassaite crystals comparison of profiles of ti3 titot ratios in several crystals with those calculated for fractional crystallization suggests that the trend in one crystal was controlled by fractional crystallization alone but in two others the virtually constant ti3 titot ratios may imply that the liquids in these inclusions were able to maintain equilibrium with the solar nebular gas throughout crystallization attempts to determine the o2 of fassaite crystallization on the basis of ti3 titot ratios must be based on fassaite grains which are not zoned with respect to ti3 titot the range of observed ree abundances in subliquidus fassaite 7 800 cl for la and 30 2000 cl for lu now encompasses those in grains previously identified as relict removing a major reason for their identification as such rounded fassaite grains with fairly sharp mg rich rims and ti rich cores poikilitically enclosed in mantle melilite in ts34 are candidates for relict grains the grains are so scrich that they would require extreme prior crystallization of spinel and melilite which is inconsistent with their very low ree contents e g la at 3 7 cl we suggest that the cores of these grains are relict and were trapped with liquid during formation of the mantle

crystallization of calcium aluminum rich inclusions experimental studies on the effects of repeated heating events the observed textures and chemistry of ca al rich inclusions cais are presumed to be the culmination of a series of repeated heating and cooling events in the early history of the solar nebula we have examined the effects of these heating cooling cycles experimentally on a bulk composition representing an average type b ca al rich inclusion composition we have tested the effect of the nature of the starting material although the most recent and or highest temperature event prior to incorporation into the parent body dominates the texture and chemistry of the cai prior events also affect the phase compositions and textures we have determined that heating precursor grains to about 1275 c prior to the final melting event increases the likelihood of anorthite crystallization in subsequent higher temperature events and a prior high temperature even that produced dendritic melilite results in melilite that shows evidence of rapid crystallization in subsequent lower temperature events prior low temperature pre crystallization events produce final ran products with pyroxene compositions similar to type b ca al rich inclusions and the glass residual liquid composition is more anorthitic than any other experiments to date the addition of pt powder to the starting material appears to enhance the ability of anorthite to nucleate from this composition

observations and numerical modeling of the 2012 haida gwaii tsunami off the coast of british columbia a major mw 7 7 earthquake occurred on october 28 2012 along the queen charlotte fault zone off the west coast of haida gwaii formerly the queen charlotte islands the earthquake was the second strongest instrumentally recorded earthquake in canadian history and generated the largest local tsunami ever recorded on the coast of british columbia a field survey on the pacific side of haida gwaii revealed maximum runup heights of up to 7 6 m at sites sheltered from storm waves and 13 m in a small inlet that is less sheltered from storms leonard and bednarski2014 the tsunami was recorded by tide gauges along the coast of british columbia by open ocean bottom pressure sensors of the neptune facility at ocean networks canada s cabled observatory located seaward of southwestern vancouver island and by several dart stations located in the northeast pacific the tsunami observations in combination with rigorous numerical modeling enabled us to determine the physical properties of this event and to correct the location of the tsunami source with respect to the initial geophysical estimates the initial model results were used to specify sites of particular interest for post tsunami field surveys on the coast of moresby island haida gwaii while field survey observations leonard and bednarski2014 were used in turn to verify the numerical simulations based on the corrected source region

the petrogenesis of type b1 ca al rich inclusions the spinel perspective minor element variations in mgal 2o 4 spinel from the type b1 calcium aluminum rich inclusion cai allende ts 34 confirm earlier studies in showing correlations between the minor element chemistry of spinels with their location within the inclusion and with the chemistry of host silicate phases these correlations result from a combination of crystallization of a liquid produced by re melting event s and local re equilibration during subsolidus reheating the correlation of the ti and v in spinel inclusions with the ti and v in the adjacent host clinopyroxene can be qualitatively explained by spinel and clinopyroxene crystallization prior to melilite following a partial melting event there are however difficulties in quantitative modeling of the observed trends and it is easier to explain the ti correlation in terms of complete re equilibration the correlation of v in spinel inclusions with that in the adjacent host clinopyroxene also cannot be quantitatively modeled by fractional crystallization of the liquid produced by re melting but it can be explained by partial re equilibration the distinct v and ti concentrations in spinel inclusions in melilite from the edge regions of the cai are best explained as being affected by only a minor degree of re equilibration the center melilites and included spinels formed during crystallization of the liquid produced by re melting while the edge melilites and included spinels are primary the oxygen isotope compositions of ts 34 spinels are uniformly 16 o rich regardless of the host silicate phase or its location within the inclusion similar to other type b1 cais clinopyroxene is 16 o rich but melilite is relatively 16 o poor these data require that the oxygen isotope exchange in ts 34 melilite occurred subsequent to the last re melting event

near field modeling of the 1964 alaska tsunami the role of splay faults and horizontal displacements near field observations of tsunami waves generated by the mw9 2 1964 alaska earthquake reveal a complex relationship between coseismic slip and the tsunami wavefield in the source area the documen

minor element partitioning and sector zoning in synthetic and meteoritic anorthite regular geometric apparently crystallographically controlled sector zoning has been produced in synthetic anorthite crystallized from a liquid of type b ca al rich inclusion cai composition cathodoluminescence cl provides a rapid method for observing the sectors sharp discontinuities in mg concentration always accompany sharp changes in cl intensity at sector boundaries although cl intensity anti correlates with mg concentration there is not a well defined quantitative relationship and mg concentration steps range from as little as 5 to almost a factor of 2 for different cl boundaries when measurable na also tends to anti correlate with cl brightness in a given crystal and thus correlates with mg the partition coefficients for mg and na can vary by up to a factor of 2 depending on the particular sector and thus are not constant for cai anorthite which formed by fractional crystallization in contrast ti either ti 3 or ti 4 concentration is not a function of sector zoning and thus does not affect the cl intensity the sector zoning and correlated chemical variations for synthetic anorthite are similar to those in natural anorthite from type b cais the cl intensity boundary sharpness and minor element zoning in synthetic anorthite are not affected by annealing at 850 c for three weeks overall our observations suggest that the observed cl patterns and minor element zoning in type b anorthite are igneous in origin and have not been modified by subsolidus reequilibration or alteration this leads to the conclusion that the 26 mg 26 al systematics in cais based almost entirely on anorthite have not been modified by subsolidus reequilibration or alteration

physical and optical properties of snow covering arctic tundra on svalbard snow thickness duration of snow coverage and amount of ice covering the soil are crucial for the development of biota in the arctic tundra environment the snow thickness and optical properties control the amount of photosynthetically active radiation par that is available for vegetation a late snow cover may prevent birds from nesting on the ground furthermore ice at the snow soil interface can be an obstacle for grazing of svalbard reindeer and affect the microfauna population snow and ice thickness and the physical and optical properties of snow covering arctic tundra were measured on the broggerhalvoya peninsula on western svalbard in spring of 1997 additionally thicknesses of ground covering ice were measured in spring of 1998 the initial maximum thickness of snow in the observed areas varied from 0 4 to 0 9 m the snow around ny alesund began to disappear by the beginning of june with the entire snow pack disappearing within 2 3 weeks at the bottom of the snow pack there was a soil covering ice layer between 0 05 and 0 1 m thick we obtained radiation and reflectance parameters spectral albedo attenuation of par and global radiation as well as physical properties of snow e g temperature and density over six weeks from early may to late june electrolytic conductivity of melted snow samples from snow pits shows clearly different conductivity for different stratigraphic sections within the snow pack in early june later on these contrasts disappeared as internal ice layers melted and the snow pack underwent percolation the albedo maximum before melt onset exceeded 0 9 whereas in the later phase of melting snow surfaces exhibited significantly lower albedo due to metamorphosis thinning and blackening by soil particle contamination however even an apparently clean snow surface had about 30 lower albedo in mid june than in mid may observations from under snow par measurements are verified using a physically based radiative transfer model this comparison indicates that scattering features that are smaller than the bulk grain size may contribute significantly to the interaction between radiation and snowpack

115 year ice core data from akademii nauk ice cap severnaya zemlya high resolution record of eurasian arctic climate change from 1999 to 2001 a 724 m deep ice core was drilled on akademii nauk ice cap severnaya zemlya to gain high resolution proxy data from the central russian arctic despite strong summertime meltwater percolation this ice core provides valuable information on the regional climate and environmental history we present data of stable water isotopes melt layer content and major ions from the uppermost 57 m of this core covering the period 1883 1998 dating was achieved by counting seasonal isotopic cycles and using reference horizons multi annual 18 o values reflect eurasian sub arctic and arctic surface air temperature variations we found strong correlations to instrumental temperature data from some stations e g r 0 62 for vardo northern norway the 18 o values show pronounced 20th century temperature changes with a strong rise about 1920 and the absolute temperature maximum in the 1930s a recent decrease in the deuterium excess time series indicates an increasing role of the kara sea as a regional moisture source from the multi annual ion variations we deduced decreasing sea salt aerosol trends in the 20th century as reflected by sodium and chloride whereas sulphate and nitrate are strongly affected by anthropogenic pollution

swash overtopping a truncated plane beach swash on a plane beach is modelled by using a solution of the shallow water equations due to shen meyer 1963 the equations are used in a form appropriate for a plane at a finite angle to the horizontal the beach is cut off at a level below that of the maximum run up and the water is taken to fall freely over the end of the beach an explicit solution is found which permits evaluation of the overtopping flow and total volume for one swash event

the origin and significance of reverse zoning in melilite from allende type b inclusions in many type b allende inclusions melilite is reversely zoned over restricted portions of each crystal textural relationships and the results of dynamic crystallization experiments suggest that the reverselyzoned intervals in these type melilites result from the co precipitation of melilite with clinopyroxene from a melt prior to the onset of anorthite precipitation when clinopyroxene begins to precipitate the al mg ratio of the melt rises causing the crystallizing melilite to become more gehlenitic an effect which is negated by crystallization of anorthite because the equilibrium crystallization sequence in these liquids is anorthite before pyroxene melilite reverse zoning can occur only when anorthite nucleation is suppressed relative to pyroxene this has been achieved in our experiments at cooling rates as low as 0 5 c hour our experiments further indicate however that reverse zoning does not form at cooling rates 50 c hour probably because the clinopyroxene becomes too al rich to drive up the al mg ratio of the liquid type inclusions with reversely zoned melilites must have cooled at rates greater than those at which anorthite begins to crystallize before clinopyroxene but 50 c hour such rates are far too slow for the type droplets to have cooled by radiation into a nebular gas but are much faster than the cooling rate of the solar nebula itself one possibility is that type b s formed in local hot regions within the nebula where their cooling rate was equal to that of their surrounding gas other possibilities are that their cooling rates reflect their movement along nebular temperature gradients or the influence of a heat source the sun or viscous drag on inclusions as they moved through the nebular gas are potential candidates for such heat sources