tropical storm induced near inertial internal waves during the cirene experiment energy fluxes and impact on vertical mixing 1 near inertial internal waves niw excited by storms and cyclones play an essential role in driving turbulent mixing in the thermocline and interior ocean storm induced mixing may be climatically relevant in regions like the thermocline ridge in the southwestern indian ocean where a shallow thermocline and strong high frequency wind activity enhance the impact of internal gravity wave induced mixing on sea surface temperature the cirene research cruise in early 2007 collected ship borne and mooring vertical profiles in this region under the effect of a developing tropical cyclone in this paper we characterize the niw field and the impact of these waves on turbulent mixing in the upper ocean niw packets were identified down to 1000 m the maximum depth of the measurements we estimated an niw vertical energy flux of up to 2 5 mw m 2 within the pycnocline which represents about 10 of the maximum local wind power input a non negligible fraction of the wind power input is hence potentially available for subsurface mixing the impact of mixing by internal waves on the upper ocean heat budget was estimated from a fine scale mixing parameterization during the first leg of the cruise characterized by little niw activity the average heating rate due to mixing was 0 06 c month 1 in the thermocline 23 24 kg m 3 isopycnals during the second leg characterized by strong niw energy in the thermocline and below this heating rate increased to 0 42 c month 1 indicative of increased shear instability along near inertial wave energy pathways

hydrogeochemistry of coal mine water of north karanpura coalfields india implication for solute acquisition processes dissolved fluxes and water quality assessment mine water samples collected from different mines of the north karanpura coalfields were analysed for ph electrical conductivity total dissolved solids tds total hardness th major anions cations and trace metals to evaluate mine water geochemistry and assess solute acquisition processes dissolved fluxes and its suitability for domestic industrial and irrigation uses mine water samples are mildly acidic to alkaline in nature the tds ranged from 185 to 1343 mg l 1 with an average of 601 mg l 1 ca2 and mg2 are the dominant cations while so4 2 and hco3 are the dominant anions a high concentration of so4 2 and a low hco3 hco3 so4 2 ratio 0 50 in the majority of the water samples suggest that either sulphide oxidation or reactions involving both carbonic acid weathering and sulphide oxidation control solute acquisition processes the mine water is undersaturated with respect to gypsum halite anhydrite fluorite aluminium hydroxide alunite amorphous silica and oversaturated with respect to goethite ferrihydrite quartz about 40 of the mine water samples are oversaturated with respect to calcite dolomite and jarosite the water quality assessment shows that the coal mine water is not suitable for direct use for drinking and domestic purposes and needs treatment before such utilization tds th f so4 2 fe mn ni and al are identified as the major objectionable parameters in these waters for drinking the coal mine water is of good to suitable category for irrigation use the mines of north karanpura coalfield annually discharge 22 35 106 m3 of water and 18 50 103 tonnes of solute loads into nearby waterways

estimation of the rupture length and velocity of the great sumatra earthquake of dec 26 2004 using hydroacoustic signals 1 unprecedented hydroacoustic observations of the megathrust earthquake of 26 dec 2004 were afforded by a network of 5 small hydroacoustic arrays located in the indian ocean at distances of 2800 to 7000 km from the epicenter each array recorded acoustic waves called t waves generated by this event analysis of a series of short time windows within the t wave coda shows that the receiver to source azimuth varies smoothly as a function of time indicating that the apparent t wave source is not stationary the apparent t wave source moves northward along the sunda trench at an average velocity of 2 km s closely tracking event rupture the hydroacoustic data suggest that the rupture proceeded in two distinct phases initially it progressed northwest along the sunda trench with a velocity of approximately 2 4 km s at 600 km from the epicenter the rupture slowed to approximately 1 5 km s as it continued to propagate to the northwest

the impact of salt fingering on the thermohaline circulation under mixed boundary conditions abstract the impact of salt fingers on the thermohaline circulation in a single hemisphere basin under mixed boundary conditions is investigated through scaling analysis and numerical experiments by assuming that the internal density ratio is determined by the surface horizontal density ratio the effect of a double diffusive parameterization on the vertical diffusivity of density k is estimated salt fingers reduce the magnitude of k with the extent of the reduction dependent on the magnitude of the density ratio the reduced diapycnal mixing leads to a diminished thermohaline circulation and modifies the stability criteria for the thermal haline mode transition under mixed boundary conditions quasi equilibrium numerical experiments with the gfdl modular ocean model produce results consistent with the scaling analysis in the reduction of the magnitude of the thermohaline circulation and the change in the critical freshwater forcing required for the existence of the stable thermal mode sensitivity

subsurface melting of a free floating antarctic iceberg abstract observations near a large tabular iceberg in the weddell sea in march and april 2009 show evidence that water from ice melting below the surface is dispersed in two distinct ways warm salty anomalies in t s diagrams suggest that water from the permanent thermocline is transported vertically as a result of turbulent entrainment of meltwater at the iceberg s base stepped profiles of temperature salinity and density in the seasonal thermocline are more characteristic of double diffusive processes that transfer meltwater horizontally away from the vertical ice face these processes contribute comparable amounts of meltwater o 0 1 m3 to the upper 200 m of a 1 m2 water column but only basal melting results in significant upwelling of water from below the winter water layer into the seasonal thermocline suggesting that these two processes may have different effects on vertical nutrient transport near an iceberg

the contribution of salt fingers to vertical mixing in the north atlantic tracer release experiment abstract the north atlantic tracer release experiment natre was performed in an area moderately favorable to salt fingers however the classic finger signature of a distinct thermohaline staircase caused by upgradient density flux was absent this is likely because mixing by turbulence was sufficiently strong to disrupt the formation of permanent step and layer systems despite the lack of a staircase optical shadowgraph profiles revealed that small scale tilted laminae previously observed in a salt finger staircase were abundant at the natre site using microstructure observations the strength of salt finger mixing has been diagnosed using a nondimensional parameter related to the ratio of the diffusivities for heat and buoyancy the dissipation ratio by examining the dissipation ratio in a parameter space of density ratio r and richardson number ri the signal of salt fingers was discerned even under conditions where turbulent mixing also occurred while the model for turbulence descr

ultralong period seismic study of the december 2004 indian ocean earthquake and implications for regional tectonics and the subduction process analysis of the earth s longest period normal modes shows that the december 2004 sumatra andaman earthquake was much larger mw 9 3 than ini tially inferred from surface wave data and involved slip on a much longer fault than initially inferred from body wave data the seismic moment and relative excitation of the normal modes indicate that the entire aftershock zone ruptured consistent with the large tsunami amplitudes in thailand sri lanka and india an apparent increase in seismic moment with period results from interference between parts of the fault the earthquake resulted from subduction of the indian plate beneath the burma microplate a sliver plate between the indian and sunda plates hence the rate and direction of convergence depends on the motion of the burma plate which is not well known convergence would be highly oblique if the rate of motion between burma and sunda is that inferred from spreading in the andaman sea and less if a slower rate is inferred from the sagaing fault the december earthquake was much larger than expected from a previously proposed relation based on the idea of seismic coupling in which such earthquakes occur only when young lithosphere subducts rapidly moreover a global reanalysis finds little support for this correlation hence we suspect that much of the apparent differences between subduction zones such as some trench segments but not others being prone to m w 8 5 events and hence oceanwide tsunamis may reflect the short earthquake history sampled this possi bility is supported by the variability in rupture mode at individual trench segments

a seismological reassessment of the source of the 1946 aleutian tsunami earthquake summary we present a re evaluation of the seismological properties of the aleutian tsunami earthquake of 1946 april 1 characterized by a deceptively low conventional magnitude 7 4 in view of its catastrophic tsunami both in the near and far fields relocation of 40 aftershocks show that the fault zone extends a minimum of 181 km along the aleutian trench in a geometry requiring a bilateral rupture from the original nucleation at the epicentre their spatial and temporal distribution are typical of the aftershock patterns of a large earthquake and rule out the model of a landslide source exclusive of a dislocation the analysis of the spectra of mantle waves favours the model of a large seismic source with a static moment of 8 5 10 28 dyn cm making the event one of the ten largest earthquakes ever recorded hence the destructive tsunami in the far field and of a slow bilateral rupture at an average velocity of only 1 12 km s 1 hence the destructive interference in all azimuths for all but the longest mantle waves the exceptionally slow character of the earthquake is confirmed by a deficiency in radiated seismic energy expressed by the lowest value measured to date of the energy tomoment ratio the earthquake appears as an end member in the family of tsunami earthquakes resulting from the combination of anomalous but not unprecedented parameters such as low stress drop and rupture velocity

low frequency source characteristics of the great 1960 chilean earthquake the low frequency nature of the great 1960 chilean earthquake the earth s largest recorded event is characterized and a source model composed of three events with a combined seismic moment of 5 5 1023 n m and a duration of 1500 s is presented the results show conclusively that large scale slip which is only observed at low frequencies preceded the main shock complex amplitude measurements of normal mode data in the band 1 0 5 0 mhz recorded at eight vertical component stations comprise the data set in this band the earthquake source is assumed to be described by a line source propagating at a constant rupture velocity the data set is the basis for a sequence of least squares inversions to determine the seismic moment rupture velocity spatial slip distribution and the temporal slip function the data are best explained by a source model that begins 1150 s before the main shock with an event of moment 1 9 1023 n m and rise time of 300 s a main shock with moment of 3 2 1023 n m and for which most of the low frequency energy was released beginning about 50 s after the short period origin time and an event 350 s later with moment of 0 4 1023 n m the uncertainty in the moment estimate of the great 1960 chilean earthquake is about 50 and is due primarily to the probable range of fault plane dip which is not well constrained at this time

observations indicative of rain induced double diffusion in the ocean surface boundary layer double diffusion can result in the formation of thermohaline staircases typically observed in the ocean interior the observations presented here were acquired in the ocean surface boundary layer with the autonomous microstructure air sea interaction profiler an intense rain event rainfall rates of up to 35 mm h resulted in cooler fresher water up to 0 15 practical salinity unit psu over the upper 7 10 m overlaying warmer saltier water a situation potentially conducive to double diffusive mixing although not as crisp as interfaces in the interior ocean because of elevated background mixing a total of 303 thermohaline interfaces were detected within and at the base of the fresh layer with mean changes in temperature t and salinity s across interfaces of 20 10 3 c and 22 10 3 psu respectively these results call for new studies to disambiguate whether such interfaces are formed through double diffusive mixing or shear instabilities and understand any long term impacts on near surface stratification

strong indian ocean sea surface temperature signals associated with the madden julian oscillation in late 2007 and early 2008 a moored buoy was recently deployed at 8 degrees s 67 degrees e in the shallow thermocline region of the indian ocean known as seychelles chagos thermocline ridge sctr where the madden julian oscillation mjo is associated with strong sea surface temperature sst variability we use observations from this mooring to describe the oceanic signature of two mjos between november 2007 and february 2008 the four month average upper ocean heat balance was largely between heating by atmospheric forcing 2 0 0 3 degrees c month and a significant cooling by subsurface processes 2 2 0 8 degrees c month consistent with climatological ekman pumping in the region the two mjo events resulted in strong intraseasonal sst variations 1 5 to 2 degrees c in similar to 20 days in the sctr at the mooring site atmospheric fluxes dominated the upper ocean heat balance at the mjo timescale with the net surface heat flux into the ocean decreasing from an average 105 w m 2 during suppressed phases to 15 w m 2 during active phases of the mjo it is difficult to establish if mjo induced variations of subsurface processes also contributed to the cooling because of large uncertainty in this term lateral advection had no systematic fluctuations on mjo timescales but cannot be neglected at the mooring site

source inversion of w phase speeding up seismic tsunami warning w phase is a long period phase arriving before s wave it can be interpreted as superposition of the fundamental first second and third overtones of spheroidal modes or rayleigh waves and has a group velocity from 4 5 to 9 km s 1 over a period range of 100 1000 s the amplitude of long period waves better represents the tsunami potential of an earthquake because of the fast group velocity of w phase most of w phase energy is contained within a short time window after the arrival of the p wave at a distance of 50 w phase energy is contained within 23 min after the origin time which is the distinct advantage of using w phase for rapid tsunami warning purposes we use a time domain deconvolution method to extract w phases from the broad band records of global seismic networks the bandwidth of w phase is approximately from 0 001 to 0 01 hz and we bandpass filter the data from 0 001 to 0 005 hz in most cases having extracted w phase from the vertical component records we perform a linear inversion using a point source to determine mw and the source mechanism for several large earthquakes including the 2004 sumatra andaman earthquake the 2005 nias earthquake the 2006 kuril is earthquake and the 2007 sumatra earthquake w phase inversion yields reliable solutions and holds promise of the use of w phase for rapid assessment of tsunami potential

spatio temporal source characteristics of the 26 december 2004 sumatra earthquake as imaged by teleseismic broadband arrays 1 we test the capability of broadband arrays at teleseismic distances to image the spatio temporal characteristics of the seismic energy release during the dec 26 2004 sumatra earthquake at early observation times using a non plane wave array location technique previously reported values for rupture length about 1150 km duration about 480 s and average rupture velocity 2 4 2 7 km s are confirmed three dominant energy releases are identified one near the hypocenter a second at 6 n 94 e about 130 s later and a third one after 300 s at 9 n 92 93 e the spatio temporal distribution of the radiated seismic energy in the source region is calculated from the stacked broadband recordings of two arrays in germany and japan and results in rough estimates of the total seismic energy of 0 55 1018 nm grsn and 1 53 1018 nm fnet respectively changes in the relative ratio of energy as function of spatio temporal location indicate a rotation of the focal mechanism during the rupture process

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

multiple cmt source analysis of the 2004 sumatra earthquake while it is agreed that the great sumatra earthquake of december 26 2004 was among the largest earthquakes of the past century there has been disagreement on how large it was which part of the fault ruptured and how the rupture took place we present a centroid moment tensor cmt analysis of the earthquake in which multiple point sources are used in the inversion to mimic a propagating slip pulse the final model consists of five point sources with the southernmost sources accounting for the majority of the moment release the presumed fault planes of the southern sources strike northwest while those in the north strike northeast consistent with the geometry of the subduction trench slip on the fault is found to be more oblique in the north than in the south the inversion with five sources leads to a moment magnitude for the sumatra earthquake of m w 9 3 consistent with estimates from long period normal mode amplitudes

the 2010 and 2011 tsunamis in french polynesia operational aspects and field surveys we present a detailed timeline of the warning procedures as they unfolded at the laboratoire de geophysique in papeete tahiti during the nights of 26 27 february 2010 maule chile tsunami and 10 11 march 2011 tohoku tsunami in particular we discuss how the flow of information available to the warning center including seismic evaluations obtained both locally and from other warning centers as well as maregraph and dart buoy data built up and eventually led to red alerts which the local authorities used in both cases to impose an evacuation of low lying areas on 68 islands while the alerts were successful in polynesia a difficulty arose in 2011 when the alert had to be reinstated immediately as the all clear was being declared since the maximum amplitude was carried by the fourth wave packet we also present a complete dataset of 119 values of run up and inundation surveyed in the aftermath of the two tsunamis principally in the marquesas islands where their effects were maximal and on tahiti and moorea for the 2011 event the highest run up 4 45 m was observed in 2011 in the bay of taipivai on nuku hiva where seven houses were flooded we find no clear correlation between run up values at the same locations in 2010 and 2011 suggesting that local responses are controlled by details specific to each tsunami in 2010 in the village of puamau on hiva oa marquesas a delayed harbor response probably due to resonance of the bay upon arrival of short period components dispersed outside the shallow water approximation flung a launch onto a wharf 7 h after the first arrivals and 2 5 h after issuance of the all clear

weathering of the new albany shale kentucky usa i weathering zones defined by mineralogy and major element composition abstract comprehensive understanding of chemical and mineralogical changes induced by weathering is valuable information when considering the supply of nutrients and toxic elements from rocks here minerals that release and fix major elements during progressive weathering of a bed of devonian new albany shale in eastern kentucky are documented samples were collected from unweathered core parent shale and across an outcrop excavated into a hillside 40 year prior to sampling quantitative x ray diffraction mineralogical data record progressive shale alteration across the outcrop mineral compositional changes reflect subtle alteration processes such as incongruent dissolution and cation exchange altered primary minerals include k feldspars plagioclase calcite pyrite and chlorite secondary minerals include jarosite gypsum goethite amorphous fe iii oxides and fe ii al sulfate salt efflorescence the mineralogy in weathered shale defines four weathered intervals on the outcrop zones a c and soil alteration of the weakly weathered shale zone a is attributed to the 40 a exposure of the shale in this zone pyrite oxidization produces acid that dissolves calcite and attacks chlorite forming gypsum jarosite and minor efflorescent salt the pre excavation active weathering front zone b is where complete pyrite oxidation and alteration of feldspar and organic matter result in increased permeability acidic weathering solutions seep through the permeable shale and evaporate on the surface forming abundant efflorescent salt jarosite and minor goethite intensely weathered shale zone c is depleted in feldspars chlorite gypsum jarosite and efflorescent salts but has retained much of its primary quartz illite and illite smectite goethite and amorphous fe iii oxides increase due to hydrolysis of jarosite enhanced permeability in this zone is due to a 14 loss of the original mass in parent shale denudation rates suggest that characteristics of zone c were acquired over 1 ma compositional differences between soil and zone c are largely attributed to illuvial processes formation of additional fe iii oxides and incorporation of modern organic matter

nickel porphyrins in the bedding planes of a colorado lean oil shale abstract a colorado lean oil shale was found to have red colored material on the faces of bedding planes and fractures this red material is almost entirely the nickel chelate of a single c 29 porphyrin of deoxophylloerythroetioporphyrin type the molecular weight of the chelate is 490 or 492 depending on which of the two major isotopes of nickel is chelated a small amount of a methylene homologue 14 mass units higher in molecular weight is also present porphyrins extracted from the powdered shale are an extended homologous series of deoxophylloerythroetioporphyrin type and possibly etio type nickel porphyrins as determined by mass spectrometry the origin of the red porphyrins coating the shale fractures and bedding planes therefore was exogenous to these particular shale samples

teleseismic inversion for rupture process of the 27 february 2010 chile mw 8 8 earthquake the 27 february 2010 chile m w 8 8 earthquake is the fifth largest earthquake to strike during the age of seismological instrumentation the faulting geometry slip distribution seismic moment and moment rate function are estimated from broadband teleseismic p sh and rayleigh wave signals we explore some of the trade offs in the rupture process estimation due to model parameterizations limited teleseismic sampling of seismic phase velocities and uncertainty in fault geometry the average slip over the 81 500 km 2 rupture area is about 5 m with slip concentrations down dip up dip and southwest and up dip and north of the hypocenter relatively little slip occurred up dip offshore of the hypocenter the average rupture velocity is 2 0 2 5 km s

source parameter inversion for recent great earthquakes from a decade long observation of global gravity fields we quantify gravity changes after great earthquakes present within the 10 year long time series of monthly gravity recovery and climate experiment grace gravity fields using spherical harmonic normal mode formulation the respective source parameters of moment tensor and double couple were estimated for the 2004 sumatra andaman earthquake the gravity data indicate a composite moment of 1 2 1023 n m with a dip of 10 in agreement with the estimate obtained at ultralong seismic periods for the 2010 maule earthquake the grace solutions range from 2 0 to 2 7 1022 n m for dips of 12 24 and centroid depths within the lower crust for the 2011 tohoku oki earthquake the estimated scalar moments range from 4 1 to 6 1 1022 n m with dips of 9 19 and centroid depths within the lower crust for the 2012 indian ocean strike slip earthquakes the gravity data delineate a composite moment of 1 9 1022 n m regardless of the centroid depth comparing favorably with the total moment of the main ruptures and aftershocks the smallest event we successfully analyzed with grace was the 2007 bengkulu earthquake with m0 5 0 1021 n m we found that the gravity data constrain the focal mechanism with the centroid only within the upper and lower crustal layers for thrust events deeper sources i e in the upper mantle could not reproduce the gravity observation as the larger rigidity and bulk modulus at mantle depths inhibit the interior from changing its volume thus reducing the negative gravity component focal mechanisms and seismic moments obtained in this study represent the behavior of the sources on temporal and spatial scales exceeding the seismic and geodetic spectrum

vertical heat transfer in the arctic ocean the role of double diffusive mixing 1 microstructure profiles collected in the central amundsen basin are analyzed in order to quantify the role of double diffusive mixing for vertical heat transfer from the atlantic layer in the profiles a persistent but laterally incoherent thermohaline staircase structure is identified in the 200 260 m depth range the staircase contains homogeneous layers with average height of 1 3 m and thin high gradient interfaces with average temperature and salinity jumps of about 0 065 c and 0 015 respectively when inferred from a commonly used diffusive convection parameterization the average vertical heat flux within the staircase is 0 6 w m 2 this is one order of magnitude larger than the molecular diffusion alone and of the same order as the overall heat loss from the atlantic layer in the deep basins of the arctic ocean the parameterization is evaluated using observed turbulent heat fluxes and is found to overestimate diffusive convective fluxes with up to an order of magnitude especially for weak thermal forcing small temperature jumps in staircase staircases coexist with thermohaline intrusions in the vertical temperature and salinity profiles lomonosov ridge is identified as a potential region for formation of intrusions it is found that salt fingering is the dominant process during intrusion growth whereas diffusive convection is the dominant process in maintaining the intrusions at steady state in the deep basins

enhanced diapycnal mixing by salt fingers in the thermocline of the tropical atlantic diapycnal mixing plays a significant role in the ocean s circulation and uptake of heat and carbon dioxide but has not been quantified in salt finger driven thermohaline staircases we recently performed a tracer release experiment in the western tropical atlantic staircase at approximately 400 m depth the observed dispersion implies an effective diapycnal diffusivity for tracer and salt of 0 8 to 0 9 x 10 4 m2 s temperature microstructure data interpreted in terms of a vertical production dissipation balance yields a smaller effective diffusivity for heat of 0 45 0 2 x 10 4 m2 s consistent with salt fingers and well above the mixing ascribable to mechanical turbulence

teleseismic estimates of radiated seismic energy the e m 0 discriminant for tsunami earthquakes we adapt the formalism of boatwright and choy for the computation of radiated seismic energy from broadband records at teleseismic distances to the real time situation when neither the depth nor the focal geometry of the source is known accurately the analysis of a large data set of more than 500 records from 52 large recent earthquakes shows that this procedure yields values of the estimated energy ee in good agreement with values computed from available source parameters for example as published by the national earthquake information center neic the average logarithmic residual being only 0 26 units we analyze the energy to moment ratio by defining log10 ee m0 for regular earthquakes this parameter agrees well with values expected from theoretical models and from the worldwide neic catalogue there is a one to one correspondence between values of that are deficient by one full unit or more and the so called tsunami earthquakes previously identified in the literature as having exceedingly slow sources and believed due to the presence of sedimentary structures in the fault zone our formalism can be applied to single station measurements and its coupling to automated real time measurements of the seismic moment using the mantle magnitude mm should significantly improve real time tsunami warning

tracing the interaction of acid mine drainage with coal utilization byproducts in a grouted mine strontium isotope study of the inactive omega coal mine west virginia usa abstract in order to ameliorate acidic discharge the inactive omega coal mine west virginia was partially filled by injection of a grout consisting of 98 coal utilization byproducts cub including fluidized bed combustion ash and fly ash and 2 portland cement in this study discharge chemistry and sr isotope ratios were determined to identify and quantify the extent of interaction between mine waters and the cub cement grout eight sampling sites were monitored around the downdip perimeter of the mine the major and trace element chemistry of the discharges was generally not sufficient to distinguish between discharges that interacted with grout and those that did not elements that showed the most separation include k and as which were elevated in some waters that interacted with cub cement grout in contrast the sr isotope ratios clearly distinguished discharges from grouted and non grouted areas discharges that bypassed the grouted portions had 87 sr 86 sr ratios ranging from 0 71510 to 0 71594 while two discharges that interacted with grout had ratios in the range of 0 71401 0 71456 the treatment inlet which includes both grouted and ungrouted discharges yielded intermediate isotopic ratios leaching experiments on cub cement grout coal and surrounding rocks are consistent with the isotopic trends observed in the discharges based on these results waters that interacted with grout received 30 40 of their sr from the cub cement grout material these results suggest that the grout material is chemically eroding at a rate of approximately 0 04 per year this novel application of the sr isotope system illustrates its ability to sensitively track and quantify fluid interaction with coal and cub based grout

ice tethered profiler observations of the double diffusive staircase in the canada basin thermocline vertical heat fluxes through the staircase are in the range 0 05 0 3 w m 2 only about one tenth of the estimated mean surface mixed layer heat flux to the sea ice it is thus concluded that the vertical transport of heat from the atlantic water in the central basin is unlikely to have a significant impact to the canada basin ocean surface heat budget icebreaker conductivity temperature depth data from the beaufort gyre freshwater experiment show that the staircase is absent at the basin periphery turbulent mixing that presumably disrupts the staircase might drive greater flux from the atlantic water at the basin boundaries and possibly dominate the regionally averaged heat flux

mineralogy and trace element geochemistry of gas shales in the united states environmental implications abstract this paper presents a compilation of published mineralogic and trace element data from nine gas shales in the united states formations analyzed include the antrim bakken barnett eagle ford haynesville marcellus new albany utica and woodford these mineralogic and trace element data can be used to assess the potential for environmental impacts during hydraulic fracturing impacts addressed in this study include 1 the potential for acid rock drainage generation during gas shale weathering 2 the distribution of trace elements in gas shales and comparison with regulatory guidelines and 3 the implications for environmental management of well cuttings the use of the mineralogic data to assess the fracability of the gas shales is also considered compilations of the mineralogy and geochemistry of gas shales can be a valuable resource for managing real and perceived environmental problems associated with their exploitation comprehensive environmental assessment to fully address these issues in addition to other potential environmental impacts will require collection and collation of additional data on the mineralogy and trace element geochemistry of gas and other hydrocarbon producing shales

split mode evidence for no ultraslow component to the source of the 2010 maule chile earthquake we present a comprehensive study of the earth s gravest spheroidal modes excited by the maule chile earthquake of 27 february 2010 using uninterrupted time series extending over a minimum of 19 and a maximum of 93 days for each of 101 station mode combinations we use the formalism of stein and geller 1977 to compute the relative excitation of the 2 l 1 singlets in the relevant geometry and obtain an estimate of the seismic moment by best fitting the observed spectrum to that of the resulting synthetic computed for the same recording window the average results for seven spheroidal and two radial modes deviate no more than 12 from the global centroid moment tensor moment of graphic 1 with no evident trend with frequency in other words we fail to document an ultralow frequency component expressed as an increase of moment with period in the source of the 2010 event this result indicates that such components are not universal features of megaquakes even though they had been documented for the 1960 chilean 2004 sumatran and 1964 alaskan events the only three events with larger moments in the past 50 years in this respect the 2010 earthquake is most comparable to the slightly smaller 2005 nias event which incidentally also featured a bilateral rupture 1 embed inline graphic 1 gif

afterslip of the 2010 chilean earthquake 1 analysis of normal mode amplitudes excited by the chilean earthquake of 27 february 2010 shows that theoretical amplitudes computed for the global centroid moment tensor solution gcmt underestimate observation for frequencies below 1 mhz data are systematically larger and there is a hint that this ratio increases toward lower frequencies amplitude ratios for the three gravest modes 0s2 0s3 and 0s4 are 1 36 1 29 and 1 22 respectively with standard error 1 being about 0 1 for each of them the most natural explanation for this observation is the occurrence of a slow afterslip assuming that this afterslip had occurred on a similar fault with dip angle 18 degrees the moment of this afterslip is estimated to be 0 26 26 percent of the gcmt solution and the rise time of about 170 seconds

the energy radiated by the 26 december 2004 sumatra andaman earthquake estimated from 10 minute p wave windows the rupture process of the m w 9 1 sumatra andaman earthquake lasted for approximately 500 sec nearly twice as long as the teleseismic time windows between the p and pp arrival times generally used to compute radiated energy in order to measure the p waves radiated by the entire earthquake we analyze records that extend from the p wave to the s wave arrival times from stations at distances 60 these 8 to 10 min windows contain the pp ppp and scp arrivals along with other multiply reflected phases to gauge the effect of including these additional phases we form the spectral ratio of the source spectrum estimated from extended windows between tp and ts to the source spectrum estimated from normal windows between tp and tpp the extended windows are analyzed as though they contained only the p pp sp wave group we analyze four smaller earthquakes that occurred in the vicinity of the m w 9 1 mainshock with similar depths and focal mechanisms these smaller events range in magnitude from an m w 6 0 aftershock of 9 january 2005 to the m w 8 6 nias earthquake that occurred to the south of the sumatra andaman earthquake on 28 march 2005 we average the spectral ratios for these four events to obtain a frequency dependent operator for the extended windows we then correct the source spectrum estimated from the extended records of the 26 december 2004 mainshock to obtain a complete or corrected source spectrum for the entire rupture process 600 sec of the great sumatra andaman earthquake our estimate of the total seismic energy radiated by this earthquake is 1 4 1017 j when we compare the corrected source spectrum for the entire earthquake to the source spectrum from the first 250 sec of the rupture process obtained from normal teleseismic windows we find that the mainshock radiated much more seismic energy in the first half of the rupture process than in the second half especially over the period range from 3 sec to 40 sec

review of the stratigraphic distribution and diagenetic history of abelsonite abstract abelsonite is a crystalline nickel ii porphyrin derived from one of the chlorophylls found only in the parachute creek member of the green river formation an eocene lacustrine deposit in the uinta basin utah since its original observation in 1969 numerous samples of abelsonite have been collected and their stratigraphic position within the formation plotted it was observed that abelsonite occurs in six distinct narrow stratigraphic zones which can be described with respect to the distribution of organic matter the zones of abelsonite occurrence were designated m9 m7 m2 l6 l0 and k1 based on green river formation stratigraphic nomenclature abelsonite displays a secondary mode of occurrence occurring in vugs fractures and along bedding lamina strongly implying migration or movement the origin of abelsonite can probably be attributed to the unique geochemical conditions of lake uinta chlorophyll diagenesis and the transport of an aqueous solution of a relatively insoluble precursor into sediments of favorable lithologic characteristics

trace element distribution and oil yield data from the parachute creek member of the green river formation colorado the determination of trace element concentrations in oil shale before mining and retorting is required for proper solid waste management planning using routine fischer assay oil yield data collected during resource characterization as indicators of potential trace element concentrations could lead to a standard method of identifying strata containing high trace element levels in order to determine a correlation between trace element concentrations and oil yield shale samples were selected from four statigraphic zones of the parachute creek member of the green river formation for analysis all samples were analyzed for total elemental concentrations mineralogy and fischer assay oil yield the results of these analyses demonstrated that the mahogany zone shales contain significantly greater trace element concentrations antimony arsenic cadmium chromium copper lead lithium mercury molybdenum nickel selenium silver and vanadium than the other three shale zones these high trace element concentrations have been identified within well defined interbedded tuff deposits in the mahogany zone in addition all trace elements evaluated except boron show either increasing or decreasing concentrations as oil yield increases within all oil shale zones with an increased number of analyses of existing oil shale cores oil yield data will be correlated to specific stratigraphic units containing high trace element concentrations

use of hydroacoustic and seismic arrays to observe rupture propagation and source extent of the mw 9 0 sumatra earthquake 1 the rupture of the sumatra earthquake mw 9 0 is complex and quite difficult to estimate using classical source inversion methods due to the exceptional rupture duration to fix the problem of geographical extent and rupture duration we use array processing of hydroacoustic and regional seismic data the cmar seismic array and the diego garcia hydroacoustic station h08s installed by the international monitoring system are respectively 15 2 and 25 7 far from the hypocenter the estimation of azimuth and velocity variations of homogeneous wave fronts across the arrays gives us the opportunity to understand how the rupture propagates the smooth and regular variations of azimuth fit a rupture extension of 1235 km and a duration of 515 s this study proves that the combination of array analysis using the different technologies installed for the ctbt is an interesting way of research for a rapid estimation of tsunamigenic earthquakes

the tsunami earthquake of 1932 june 22 in manzanillo mexico seismological study and tsunami simulations summary we conduct a detailed seismological study of the large colima mexico earthquake of 1932 june 3 and of its aftershocks of june 18 and 22 the latter event iii generated a tsunami more devastating than that of the main shock despite much smaller seismic magnitudes thus qualifying as a so called tsunami earthquake relocation based on published arrival times shows that event iii took place up dip of the main shock the analysis of the spectral amplitude of mantle surface waves yields low frequency moments of 24 5 2 and 4 times 1027 dyn cm respectively with event iii featuring a moment growing with period which expresses the source slowness characteristic of tsunami earthquakes this is confirmed by a deficient energy to moment ratio as derived from high frequency p waves recorded at pasadena near field hydrodynamic simulations show that the effects of the main shock s tsunami are well modelled by a standard seismic source whereas the stronger tsunami from event iii can be modelled by rupture along a splay fault in a mechanically deficient material all our results then fit the model for tsunami earthquake aftershocks proposed for the kuril islands by fukao in 1979

an evaluation of trace element release associated with acid mine drainage the determination of trace element release from geologic materials such as oil shale and coal overburden is important for proper solid waste management planning the objective of this study was to determine a correlation between trace element residency and concentration to trace element release using the following methods 1 sequential selective dissolution for determining trace element residencies 2 toxicity characteristic leaching procedure tclp and 3 humidity cell weathering study simulating maximum trace element release two eastern oil shales were used a new albany shale that contains 4 6 percent pyrite and a chattanooga shale that contains 1 5 percent pyrite each shale was analyzed for elemental concentrations by soluble adsorbed organic carbonate and sulfide phases all leachates were analyzed to determine total trace element concentrations

observations of ultra long period normal modes from the 2004 sumatra andaman earthquake abstract the great december 2004 sumatra andaman earthquake was the first giant or extreme moment magnitude mw 9 earthquake recorded by broadband digital seismometers whose data were rapidly available to investigators worldwide as a result analysis of the earth s longest period normal modes became a primary tool for studying the earthquake rather than an elegant afterthought the mode data provided the first evidence that the earthquake was much larger mw 9 3 than initially inferred from surface wave data and involved slip on a much longer fault than initially inferred from body wave data these observations in turn yielded important insight into the likely recurrence of similar earthquakes and the resulting tsunamis both on the segment of the trench that ruptured and on neighboring segments the normal mode data are more numerous and much higher quality than previously available they thus provide the first direct evidence for effects that had been theoretically predicted such as the control of the splitting pattern by receiver latitude and the splitting of torsional modes they similarly yield better results for mode properties such as the attenuation of the longest period radial modes found in agreement with existing models of intrinsic earth attenuation

from 3 hz p waves to 0 s 2 no evidence of a slow component to the source of the 2011 tohoku earthquake in the hours following the 2011 honshu event and as part of tsunami warning procedures at the laboratoire de geophysique in papeete tahiti the seismic source of the event was analyzed using a number of real time procedures the ultra long period mantle magnitude algorithm suggests a static moment of 4 1 1029 dyn cm not significantly different from the national earthquake information center neic value obtained by w phase inversion the slowness parameter uptheta 5 65 is slightly deficient but characteristic of other large subduction events such as nias 2005 or peru 2001 it remains significantly larger than for slow earthquakes such as sumatra 2004 or mentawai 2010 similarly the duration of high frequency 2 4 hz p waves in relation to seismic moment or estimated energy fails to document any slowness in the seismic source these results were confirmed in the ensuing weeks by the analysis of the lowest frequency spheroidal modes of the earth a dataset of 117 fits for eight modes including the gravest one 0s2 and the breathing mode 0s0 yields a remarkably flat spectrum with an average moment of 3 5 1029 dyn cm 1 07 this behavior of the tohoku earthquake explains the generally successful real time modeling of its teleseismic tsunami based on available seismic source scaling laws on the other hand it confirms the dichotomy among mega quakes m0 1029 dyn cm between regular events nias 2005 chile 2010 sendai 2011 and slow ones chile 1960 alaska 1964 sumatra 2004 and probably rat island 1965 whose origin remains unexplained

long period toroidal earth free oscillations from the great sumatra andaman earthquake observed by paired laser extensometers in gran sasso italy summary strain data recorded by two crossed laser extensometers operating in the gran sasso underground observatory recorded seismic free oscillations excited by the 2004 december 26 sumatra andaman earthquake the main source of instrumental noise can be mitigated by differencing data from the crossed strainmeter arms so that the resulting differential strain data set offers an unprecedented resolution of the seismic toroidal free oscillations with periods t 1000 s we reconstruct the time evolution of selected free oscillations for comparison with synthetic seismograms that include normal mode coupling effects from coriolis force attenuation and ellipticity envelopes estimated for the gran sasso differential data set for free oscillations with period t 1 mhz are approximated adequately by a composite centroid moment tensor cmt source with five subevents and an aggregate mw 9 3 moment magnitude envelopes for several toroidal free oscillations with t 1000 s are predicted less well the amplitude of the rarely observed mode 0t2 is overpredicted at gran sasso by roughly a factor of two and other modes are underpredicted the amplitude discrepancy for 0t2 is confirmed at selected exceptionally low noise seismic stations hypothetical explanations include a slow slip component of the seismic moment release errors in the composite cmt source model unmodelled coupling effects to earth s secular modes and feedback from the sumatra andaman tsunami on indian ocean coastlines of these hypotheses either an extended duration strain release or tsunami feedback seem most plausible the viability of the tsunami feedback mechansim deserves further investigation

pollution of a water course impacted by acid mine drainage in the imgok creek of the gangreung coal field korea abstract the purposes of this study are to i determine the geochemical characteristics of imgok creek impacted by acid mine drainage amd generated from abandoned coal mines ii to assess the pollution of heavy metals in the stream sediments and soils and iii to identify the chemical form of fe precipitates collected in the study area where there are 4 abandoned coal mines which belong to the grangreung coal field at the eastern part of korea amd generated from mine adits and coal refuse piles shows low ph and high concentrations of fe al and so 4 especially in the youngdong coal mine in imgok creek ph values increased and total dissolved solids tds values decreased with distance the concentrations of toxic heavy metals and major cations except fe decreased by dilution but the concentration of fe decreased rapidly due to the formation of precipitates the quality of groundwater samples did not exceed the korean drinking water standard in the stream sediments the concentrations of fe are relatively high in the youngdong tributary and imgok creek but the concentrations of heavy metals are similar to those of unpolluted sediments pollution indices of agricultural soils range from 0 28 to 0 47 yellowish red fe precipitates collected in the study area turned out to be amorphous or poorly crystallized minerals determined by x ray diffraction patterns and fe ox fe tot ratios and to contain chemically bonded so 4 and oh determined by infra red ir spectral analysis with these the mol ratios of fe s ranging from 4 6 to 6 1 determined by electron probe micro analysis epma in precipitates strongly support the existence of schwertmannite

an implosive component to the source of the deep sea of okhotsk earthquake of 24 may 2013 evidence from radial modes and cmt inversion abstract we study the spectral amplitudes of the first two earth radial modes 0 s 0 and 1 s 0 excited by the sea of okhotsk earthquake of 24 may 2013 the largest deep event ever recorded in the search for an isotropic component to its source in contrast to the case of the 1994 bolivian earthquake we detect an implosive component m i 1 1 10 27 dyn cm equivalent to 3 of the full scalar moment but 14 of the lone deviatoric component exciting the earth s radial modes an independent moment tensor inversion using the standard globalcmt algorithm but after relaxing its zero trace constraint similarly yields an implosive isotropic component albeit with a larger amplitude while it fails to document one in the case of the 1994 bolivian deep earthquake an implosive component to the source is expected in the model of transformational faulting in which deep earthquake rupture nucleates and grows upon transformation of metastable olivine to ringwoodite in the cold subducting slab this interpretation is supported by quantitative estimates 0 9 4 m of the thickness of the transformed shear zone which scale favorably relative to earthquake fault length with the upper end of the range of laboratory results reported for ices germanates and silicates the resulting extent of the transformation in the metastable wedge is consistent with the local geometry of the deep slab as recently determined by rupture modeling and aftershock distribution our results are in contrast to those for the two runner up largest deep earthquakes the 1994 bolivian and 1970 colombian shocks for which a similar isotropic component could not be detected we attribute this difference to variability in the ratio of isotropic to deviatoric components which combined with the smaller size of the 1970 and 1994 events would make any putative implosive component fall below detection levels especially in the case of the 1970 colombian earthquake for which only analog narrow band records were available

hydrogeochemistry of mine surface and groundwaters from the sanggok mine creek in the upper chungju lake republic of korea the sanggok mine used to be one of the largest lead zinc mines in the hwanggangri mining district republic of korea the present study characterizes the heavy metal contamination in the abandoned sanggok mine creek on the basis of physico chemical properties of various kinds of water samples mine surface and groundwater hydrochemistry of the water samples is characterized by the relatively significant enrichment of ca2 hco3 no3 and cl in the surface and groundwaters whereas the mine water is relatively enriched in ca2 mg2 heavy metals and hco3 and so4 2 the more polluted mine water has a lower ph and higher eh conductivity and tds values the concentrations of some toxic elements al as cd cu fe mn pb se sr pb and zn are tens to hundreds of times higher in the mine water than in the unpolluted surface and groundwaters however most immobile toxic pollutants from the mine drainage were quickly removed from the surface water by the precipitation of al and fe oxyhydroxides geochemical modeling showed that potentially toxic heavy metals might exist largely in the forms of mso4 2 and m2 in the mine water these metals in the surface and groundwaters could form m2 co3 2 and oh complex ions computer simulation indicates that the saturation indices of albite alunite anhydrite chlorite fluorite gypsum halloysite and strontianite in the water samples are undersaturated and have progressively evolved toward the saturation condition however barite calcite chalcedony dolomite gibbsite illite and quartz were in equilibrium and only clay minerals were supersaturated ground and mine waters seemed to be in equilibrium with kaolinite field but some surface water were in equilibrium with gibbsite and seceded from the stability field of quartz this indicates that surface water samples in reaction with carbonate rocks would first equilibrate with carbonate minerals then gibbsite to kaolinite investigations on water quality and environmental improvement of the severely polluted sanggok creek as well as remediation methods on the possible future pollution of the groundwater by the acid mine drainage from the abandoned metal mines are urgently required

double diffusive recipes part i large scale dynamics of thermohaline staircases abstractthree dimensional dynamics of thermohaline staircases are investigated using a series of basin scale staircase resolving numerical simulations the computational domain and forcing fields are chosen to reflect the size and structure of the north atlantic subtropical thermocline salt finger transport is parameterized using the flux gradient formulation based on a suite of recent direct numerical simulations analysis of the spontaneous generation of thermohaline staircases suggests that thermohaline layering is a product of the gamma instability associated with the variation of the flux ratio with the density ratio after their formation numerical staircases undergo a series of merging events which systematically increase the size of layers ultimately the system evolves into a steady equilibrium state with pronounced layers 20 50 m thick the size of the region occupied by thermohaline staircases is controlled by the competition between turbulent mixing and double diffusion assuming in acc

assessment of contamination load on water soil and sediment affected by the kongjujeil mine drainage republic of korea environmental pollution in the kongjujeil mine creek was determined on the basis of physicochemical and mineralogical properties for various kinds of waters soils precipitates and sediments collected in august and december 1998 the hydrochemistry of water is characterized by an enrichment in concentrations of ca2 si alkali ions no3 and cl in ground and surface water where relatively the mine waters are significantly enriched in ca2 mg2 al heavy metals and so42 concentrations the mine waters have lower ph 3 24 and higher ec 613 s cm compared with those of ground and surface water the ranges of d and 18o values smow in the water are 50 2 to 61 6 and 7 0 to 8 6 using a computer code the saturation indices of albite calcite and dolomite in the mine water show that it is undersaturated and has progressively evolved toward the equilibrium state ground and surface water are nearly saturated the gibbsite kaolinite and smectite are supersaturated in the surface and groundwater geochemical modeling shows that mostly toxic metals exist largely in the form of metal sulfates and free metals in mine water these metals in the surrounding fresh water could be formed of carbonate or hydroxide complex ions minerals within the soil and sediment near the mining area were partly variable consisting of quartz mica alkali feldspar plagioclase chlorite vermiculite berthierine and clay minerals the separated heavy minerals soil and sediment are composed of some pyrite arsenopyrite chalcopyrite sphalerite galena malachite goethite and various hydroxide minerals some potentially toxic elements as cd cu pb sb and zn are found in extremely high concentrations in the surface soils in the vicinity of the mine the enrichment index of heavy metals in sediment and surface soil of the mine drainage was very severe while it was not so great in the cultivated soil

on noise reduction in vertical seismic records below 2 mhz using local barometric pressure we propose a simple method for the reduction of noise in vertical seismic recordings at frequencies below 2 mhz the method consists in subtracting the locally recorded scaled atmospheric pressure signal from the gravity record the scale factor is frequency independent and can be linearly estimated from the data while such a pressure correction was previously only used in the analysis of tidal records it is equally efficient at the low frequency end of the normal mode band and we use gravity recordings of the big 1994 shikotan and bolivian quakes to demonstrate this point our examples also show that this correction permits to achieve noise levels well below the new low noise model nlnm peterson 1993 the success of the correction also sheds some light on the physical processes responsible for the generation of low frequency seismic noise at quiet observatories