deposit from a giant wave on the island of lanai hawaii limestone bearing gravel the newly named hulopoe gravel blankets the coastal slopes on lanai the deposit which reaches a maximum altitude of 326 meters formerly was believed to have been deposited along several different ancient marine strandlines but dated submerged coral reefs and tide gauge measurements indicate that the southeastern hawaiian islands sink so fast that former worldwide high stands of the sea now lie beneath local sea level evidence indicates that the hulopoe gravel and similar deposits on nearby islands were deposited during the pleistocene by a giant wave generated by a submarine landslide on a sea scarp south of lanai

the interaction of acid mine drainage with a carbonate terrane evidence from the obey river north central tennessee abstract the production of acidic drainage from active or abandoned coal mines is controlled by a complex series of reactions triggered by the oxidation of sulphide minerals limestone is frequently used as a neutralizing agent neutralization occurs both through dissolution of the limestone and exsolution of carbon dioxide from the water demonstration of these processes in a natural system is provided by the east fork of the obey river where acidic mine waters travel through conduits in limestone bedrock for several kilometers application of discharge concentration relationships allows tracking of the evolution of these waters within the karst aquifer several trends are evident virtually all of the iron in the acid mine drainage is precipitated along the flow path within the limestone the h released during this reaction together with the h generated by pyrite oxidation is largely neutralized by both exsolution of co 2 and dissolution of calcite dolomite in the carbonate bedrock releasing calcium and magnesium nevertheless the ph is still sufficiently low that all bicarbonate is converted to carbonic acid leaching of clay minerals by the acid waters releases small amounts of al and si the species cl f and no 3 are more or less inert the sulphate concentration substantially increases during evolution of the acid drainage this seems to be related to an input of sulphate enriched waters that have dissolved gypsum anhydrite as they follow deep flow paths within the limestone calculations of the relative proportions of h removed by reaction with calcite dolomite and co 2 degassing show that the latter is important in acidic waters that have reacted significantly with limestone and can readily lose co 2 to the atmosphere these results indicate that acid neutralization through carbonic acid dissociation in addition to neutralization through dissolution of carbonates is a useful method for the commercial a batement of acid mine drainage

the morphology and distribution of submerged reefs in the maui nui complex hawaii new insights into their evolution since the early pleistocene reef drowning and backstepping have long been recognised as reef responses to sea level rise on subsiding margins during the late pleistocene 500 14 ka hawaiian reefs grew in response to rapid subsidence and 120 m 100 kyr sea level cycles with recent work on the submerged drowned reefs around the big island of hawaii and in other locations from the last deglacial providing insight into reef development under these conditions in contrast reefs of the early pleistocene 1 8 0 8 ma remain largely unexplored despite developing in response to significantly different 60 70 m 41 kyr sea level cycles the maui nui complex mnc forming the islands of maui molokai lanai and kahoolawe provides a natural laboratory to study reef evolution throughout this time period as recent data indicate the reefs grew from 1 1 to 0 5 ma we use new high resolution bathymetric and backscatter data as well as sub bottom profiling seismic data and field observations from rov and submersible dives to make a detailed analysis of reef morphology and structure around the mnc we focus specifically on the south central region of the complex that provides the best reef exposure and find that the morphology of the reefs varies both regionally and temporally within this region barrier and pinnacle features dominate the steeper margins in the north of the study area whilst broad backstepping of the reefs is observed in the south within the au au channel in the central region between the islands closely spaced reef and karst morphology indicates repeated subaerial exposure we propose that this variation in the morphology and structure of the reefs within the mnc has been controlled by three main factors the subsidence rate of the complex the amplitude and period of eustatic sea level cycles and the slope and continuity of the basement substrate we provide a model of reef development within the mnc over the last 1 2 ma highlighting the effect that the interaction of these factors had on reef morphology

the ancient shorelines of lanai hawaii revisited abstract three ancient shorelines the mahana kaluakapo and manele have been described at elevations of 365 190 and 170 m in the kaluakapo crater lanai hawaii bernice p bishop mus bull 237 1978 1 stearns original observation of a fossil bearing outcrop at 326 m was interpreted as an ancient shoreline subsequently moore and moore 1984 1988 science 226 1984 1312 geol soc am spec pap 229 1988 101 argued that stearns fossil evidence represented the highest inundation of tsunami waves associated with the collapse of the flanks of the hawaiian islands chain the giant wave hypothesis gwh subsequently stearns fossil bearing swale site has never been observed geological field studies of kaluakapo crater were conducted to clarify the nature of the highest coral bearing outcrops preserved on lanai these field studies found no support for a shoreline at 326 m however the field studies did document a shingle terrace with numerous coral clasts at 190 m elevation we find in situ fossil bearing marine deposits at 170 m elevation within kaluakapo crater furthermore we observe the undisturbed nature of marine deposits at 190 m the preservation of fine grained materials at 170 m the absence of in situ deposits with a biological component between 200 and 365 m the dearth of rounded boulders lacking weathering rinds between 200 and 365 m and the lack of post depositional burial of the terrace deposit despite loose debris being present on the high ground surrounding the 190 m terrace these observations lead us to believe that erosion by the hypothesized giant waves did not take place our observations are inconsistent with the giant wave tsunami inundation of the kaluakapo crater area thus we concur with stearns 1938 1978 geol soc am bull 49 1938 615 bernice p bishop mus bull 237 1978 1 jones 1993 jones a t 1993 elevated fossil coral deposits in the hawaiian islands a measure of island uplift in the quaternary phd dissertation department of oceanography university of hawaii 1 274 and grigg and jones 1997 mar geol 141 1997 11 that the coral bearing deposits on lanai represent ancient shorelines and reflect a history of uplift of the island associated with lithospheric deformation of the sea floor around the hawaiian hot spot

early pleistocene origin of reefs around lanai hawaii a sequence of submerged terraces l1 l12 offshore lanai was previously interpreted as reefal and correlated with a similar series of reef terraces offshore hawaii island whose ages are known to be 500 ka we present bathymetric observational lithologic and 51 87sr 86sr isotopic measurements for the submerged lanai terraces ranging from 300 to 1000 m l3 l12 that indicate that these terraces are drowned reef systems that grew in shallow coral reef to intermediate and deeper fore reef slope settings since the early pleistocene age estimates based on 87sr 86sr isotopic measurements on corals coralline algae echinoids and bulk sediments although lacking the precision not vert similar 0 23 ma to distinguish the age depth relationship and drowning times of individual reefs indicate that the l12 l3 reefs range in age from not vert similar 1 3 0 5 ma and are therefore about 0 5 0 8 ma older than the corresponding reefs around the flanks of hawaii these new age data despite their lack of precision and the influence of later stage submarine diagenesis on some analyzed corals clearly revise the previous correlations between the reefs off lanai and hawaii soon after the end of major shield building not vert similar 1 3 1 2 ma the lanai reefs initiated growth and went through a period of rapid subsidence and reef drowning associated with glacial interglacial cycles similar to that experienced by the hawaii reefs however their early pleistocene initiation means they experienced a longer more complex growth history than their hawaii counterparts

accelerated pleistocene coral extinctions in the caribbean basin shown by uranium lead u pb dating ages of corals and shallow marine sequences define rates of marine invertebrate evolution tectonic uplift and paleoclimate change yet accurate ages are difficult to obtain prior to the late pleistocene we report a new approach for combining uranium lead u pb and uranium series dating for middle pleistocene corals from the caribbean side of costa rica two corals have 230 th 238 u in secular equilibrium small excesses in 234 u and 206 pb 238 u ages of 1 02 0 07 ma and 1 288 0 034 ma the latter coral age dates a recognized geomagnetic event to ca 1 3 ma a time at which no polarity events had been identified the new ages also show that the major coral extinction in the caribbean basin occurred shortly after 1 0 0 9 ma much more recently than previously thought this coral extinction now coincides with the global change at 1 0 0 8 ma to the current pattern of glacial interglacial cycles and amplified changes in sea level these factors may have provided a new strong environmental mechanism for rapid habitat modification and coral extinction

laboratory and field evaluation of a flushable oxic limestone drain for treatment of net acidic drainage from a flooded anthracite mine pennsylvania usa abstract this paper demonstrates the use of dissolution rate data obtained in the laboratory to indicate the potential quality of effluent from a field scale oxic limestone drain old treatment system for neutralization of dilute acidic mine drainage amd effluent from the reevesdale mine south dip tunnel a large source of amd and base flow to the wabash creek and little schuylkill river in the southern anthracite coalfield of east central pennsylvania is representative of amd with low concentrations but high loadings of dissolved fe al and other metals because of a high flow rate in january 2003 rapid neutralization of the amd from the reevesdale mine was achieved in laboratory tests of its reaction rate with crushed limestone in closed collapsible containers cubitainers the tests showed that net alkaline effluent could be achieved with retention times greater than 3 h and that effluent alkalinities and associated dissolution rates were equivalent for fe oh 3 coated and uncoated limestone on the basis of the laboratory results a flushable old containing 1450 metric tons of high purity calcitic limestone followed by two 0 7 m deep wetlands were constructed at the reevesdale mine during the first year of operation monthly data at the inflow outflow and intermediate points within the treatment system were collected april 2006 2007 the inflow to the treatment system ranged from 6 8 to 27 4 l s with median ph of 4 7 net acidity of 9 1 mg l caco 3 and concentrations of dissolved al fe and mn of 1 0 1 9 and 0 89 mg l respectively the corresponding effluent from the old had computed void volume retention times of 4 5 18 h with median ph of 6 6 net acidity of 93 2 mg l caco 3 and concentrations of dissolved al fe and mn of

uplift caused by lithospheric flexure in the hawaiian archipelago as revealed by elevated coral deposits the presence of definitive indicators of sea level such as corals found in growth position coralline beach deposits wave cut notches and wave eroded terraces all at elevations above known levels of eustatic sea level during the past 500 ka provides strong evidence that uplift has occurred in the central high hawaiian islands lithospheric flexure is proposed as the mechanism for uplift the modelled wavelength and amplitude of flexure roughly correspond to the distance and height of elevated coral rich deposits a trend of increasing age of coralline beach deposits with elevation on oahu and molokai adds support to the uplift hypothesis data and observations presented in this paper are inconsistent with a tsunami origin for most elevated deposits on lanai molokai and oahu a giant wave origin may only apply to scattered and localized deposits concentrated in low lying gulches 100 m such as those on lanai

geochemistry of highly acidic mine water following disposal into a natural lake with carbonate bedrock abstract acid mine drainage amd from the zn pb ag bi cu deposit of cerro de pasco central peru and waste water from a cu extraction plant has been discharged since 1981 into lake yanamate a natural lake with carbonate bedrock the lake has developed a highly acidic ph of 1 mean lake water chemistry was characterized by 16 775 mg l acidity as caco3 4330 mg l fe and 29 250 mg l so4 mean trace element concentrations were 86 8 mg l cu 493 mg l zn 2 9 mg l pb and 48 mg l as which did not differ greatly from the discharged amd most elements showed increasing concentrations from the surface to the lake bottom at a maximal depth of 41 m e g from 3581 to 5433 mg l fe and 25 609 to 35 959 mg l so4 the variations in the h and o isotope compositions and the element concentrations within the upper 10 m of the water column suggest mixing with recently discharged amd shallow groundwater and precipitation waters below 15 m a stagnant zone had developed gypsum saturation index si 0 25 and anglesite si 0 1 were in equilibrium with lake water jarosite was oversaturated si 1 7 in the upper part of the water column resulting in downward settling and re dissolution in the lower part of the water column si 0 7 accordingly jarosite was only found in sediments from less than 7 m water depth at the lake bottom a layer of gel like material 90 wt water of ph 1 with a total organic c content of up to 4 40 wet wt originated from the kerosene discharge of the cu extraction plant and had contaminant element concentrations similar to the lake water below the organic layer followed a layer of gypsum with ph 1 5 which overlaid the dissolving carbonate sediments of ph 5 3 7 in these two layers the contaminant elements were enriched compared to lake water in the sequence as

age of 360 m reef terrace hawaii and the rate of late pleistocene subsidence of the island observations from a manned submersible vehicle indicate that the 360 m reef terrace northwest of the island of hawaii is a drowned coral reef the preferred uranium series age of coralline algae collected from the reef face is 120 5 ka this age agrees with the notion that the reef was drowned during the sea level rise following the major lowstand of the sea that occurred at 145 ka oxygen isotope stage 6 this drowning pattern is similar to the previously determined radiocarbon age of 13 ka for drowning of the 150 m reef off west hawaii which drowned during the sea level rise following the last major lowstand of the sea at 18 ka oxygen isotope stage 2 estimated average subsidence of the reef site off northwest hawaii is 2 7 mm yr since final drowning of the 360 m reef

palaeoenvironmental records from fossil corals the effects of submarine diagenesis on temperature and climate estimates the geochemistry of coral skeletons may reflect seawater conditions at the time of deposition and the analysis of fossil skeletons offers a method to reconstruct past climate however the precipitation of cements in the primary coral skeleton during diagenesis may significantly affect bulk skeletal geochemistry we used secondary ion mass spectrometry sims to measure sr mg b u and ba concentrations in primary coral aragonite and aragonite and calcite cements in fossil porites corals from submerged reefs around the hawaiian islands cement and primary coral geochemistry were significantly different in all corals we estimate the effects of cement inclusion on climate estimates from drilled coral samples which combine cements and primary coral aragonite secondary 1 calcite or not vert similar2 aragonite cement contamination significantly affects sr ca sst estimates by 1 c and 0 4 to 0 9 c respectively cement inclusion also significantly affects mg ca b ca and u ca sst estimates in some corals x ray diffraction xrd will not detect secondary aragonite cements and significant calcite contamination may be below the limit of detection not vert similar1 of the technique thorough petrographic examination of fossils is therefore essential to confirm that they are pristine before bulk drilled samples are analysed to confirm that the geochemistry of the original coral structures is not affected by the precipitation of cements in adjacent pore spaces we analysed the primary coral aragonite in cemented and uncemented areas of the skeleton sr ca b ca and u ca of primary coral aragonite is not affected by the presence of cements in adjacent interskeletal pore spaces i e the coral structures maintain their original composition and selective sims analysis of these structures offers a route to the reconstruction of accurate ssts from altered coral skeletons however mg ca and ba ca of primary coral aragonite are significantly higher in parts of skeletons infilled with high mg calcite cement we hypothesise this reflects cement infilling of intraskeletal pore spaces in the primary coral structure

an re os date for molybdenite bearing quartz vein mineralization within the kangerlussuaq alkaline complex east greenland implications for the timing of regional metallogenesis the kangerlussuaq alkaline complex east greenland is one of the largest alkaline complexes in the world it is known to host a number of occurrences of base and precious metal mineralization including the flammefjeld porphyry mo deposits and a suite of epithermal style base and precious metal veins in an area around the sondre syenitgletscher here we describe and date a previously unknown occurrence of molybdenite pyrite scheelite bearing quartz veins associated with alkali basalt dikes that intrude the main syenites of the complex the veins appear to be cogenetic with the dikes which crosscut and brecciate granodiorites of the cirque 1320 complex sulfur isotope signatures of molybdenite and pyrite in the veins give a tight range with mean 34 s of 2 2 0 7 consistent with a magmatic s source related to the intrusion of the dikes molybdenite from the veins gave an re os age of 52 74 0 26 ma some 13 m y older than molybdenite at the flammefjeld porphyry deposit thus distinguishing this metallogenic episode as a distinct event temporally unrelated to the known mo mineralization at flammefjeld significantly in terms of the timing of regional metallogenesis and magmatism our date suggests that the age of the kangerlussuaq alkaline complex itself may be slightly older than the 50 ma currently accepted based on 40 ar 39 ar dating from biotites in the main syenites given the common discrepancy in ore systems of 40 ar 39 ar which produce slightly younger dates than those by re os and u pb we suggest the actual age of the kangerlussuaq alkaline complex may be closer to 53 to 52 ma

megatsunami deposits on kohala volcano hawaii from flank collapse of mauna loa the origin of coastal and high elevation marine gravels on the hawaiian islands of lanai and molokai is controversial because the vertical tectonics of these islands is poorly constrained the gravels are either from eustatic highstands or were left by massive tsunamis from offshore giant landslides in contrast at kohala on the island of hawaii where continuous subsidence is well established lithofacies analysis and dating of a fossiliferous marine conglomerate 1 5 61 m above present sea level support a tsunami origin and indicate a runup of 400 m 6 km inland the conglomerate age 110 10 ka suggests a tsunami caused by the ca 120 ka giant alika 2 landslide from nearby mauna loa volcano

coupling effect of fe3 aq and biological nano sized fes coated limestone on the removal of redox sensitive contaminants as sb and cr implications for in situ passive treatment of acid mine drainage nano sized fes particles have been shown to improve the adsorption performance in permeable reactive barrier prb technologies that are used to treat acid mine drainage to investigate the coupling effect of fe3 and biological nano sized fes on removal of redox sensitive contaminants and the permeability of a limestone system fe reducing bacteria frb and sulfate reducing bacteria srb were used to form nano sized fes coatings on limestone grains for initial acidic solutions containing 0 5 mg l as v cr vi and sb v retardation factors increase from 26 5 and 7 respectively in a limestone only pristine system to 367 89 and 9 respectively in an fes coated limestone system and to 345 367 and 308 respectively in an fes fe3 aq system the permeability coefficient of the fes coated limestone system is better than that of the pristine limestone system but declines to two thirds of the pristine limestone system in the presence of fe3 aq possibly due to the formation of secondary ferric hydroxides xps analysis suggests that the fes particles are effective at reducing as v sb v and cr vi and removing them from solution these results demonstrate that fes particles improve retention of redox sensitive contaminants with and without fe3 aq these new findings give new insights on the coupling effect of redox systems used in prbs

the 40ar 39ar dating of core recovered by the hawaii scientific drilling project phase 2 hilo hawaii 1 the hawaii scientific drilling project phase 2 hsdp 2 recovered core from a 3 1 km thick section through the eastern flanks of mauna loa and mauna kea volcanoes we report results of 40ar 39ar incremental heating by broad beam infrared laser of 16 basaltic groundmass samples and 1 plagioclase separate mostly from k poor tholeiites the tholeiites generally have mean radiogenic 40ar enrichments of 1 3 and some contain excess 40ar however isochron ages of glass poor samples preserve stratigraphic order in all cases a 246 m thick sequence of mauna loa tholeiitic lavas yields an isochron age of 122 86 kyr all errors 2 at its base beneath the mauna loa overlap sequence lie mauna kea s postshield and shield sequences a postshield alkalic lava yields an age of 236 16 kyr in agreement with an age of 240 14 kyr for a geochemically correlative flow in the nearby hsdp 1 core hole where more complete dating of the postshield sequence shows it to have accumulated at 0 9 0 4 m kyr from about 330 to 200 ka mauna kea s shield consists of subaerial tholeiitic flows to a depth of 1079 m below sea level then shallow submarine flows hyaloclastites pillow lavas and minor intrusions to core bottom at 3098 m most subaerial tholeiitic flows fail to form isochrons however a sample at 984 m yields an age of 370 180 kyr consistent with ages from similar levels in hsdp 1 submarine tholeiites including shallow marine vitrophyres clasts from hyaloclastites and pillow lavas were analyzed however only pillow lava cores from 2243 2614 and 2789 m yield reliable ages of 482 67 560 150 and 683 82 kyr respectively a linear fit to ages for shield samples defines a mean accumulation rate of 8 6 3 1 m kyr and extrapolates to 635 kyr at core bottom alternatively a model relating mauna kea s growth to transport across the hawaiian hot spot that predicts downward accelerating accumulation rates that reach 20 m kyr at core bottom depaolo and stolper 1996 is also consistent with all reliable ages except the deepest

strontium isotope stratigraphy of kita daito jima atoll north philippine sea implications for neogene sea level change and tectonic history abstract a detailed chronology of a 432 m core from kita daito jima an atoll on the philippine sea plate has been obtained by strontium isotope stratigraphy the atoll carbonate extends to late oligocene age the top 100 m plio pleistocene section of the core has been dolomitized and dolomite also extends to middle miocene sediments sr isotopes identify two dolomitization events at 2 and 5 ma atoll growth appears to have been continuous between 18 8 and 24 3 ma and the fit of the growth history to a standard model provides a successful confirmation of darwin s subsidence theory the atoll growth appears to have commenced about 42 ma ago 6 ma after volcanism producing a 2 km column of atoll carbonate in agreement with bathymetry the subsidence model defines an apparent loss of 360 m of the sedimentary record since the early middle miocene boundary the amount in excess of the 100 m associated with sea level fall is attributed to plio pleistocene uplift at rates of 20 30 m ma associated with the forebulge of the philippine sea plate prior to its subduction uplift rates have also been estimated using a the heights of dated last interglacial coral reefs on kita daito jima and nearby minami daito jima 17 m ma and 29 m ma b sr isotope ages of calcites from surface samples on minami daito jima 21 m ma and c contrasts in elevation with okino daito jima 100 km away 22 m ma the locations of hiatuses and ages of dolomitization indicate sea level falls of 80 m at 17 16 ma 30 m at 16 15 ma 125 m at 11 ma and 90 m at 5 ma and at 2 ma the data have been combined with those from enewetak atoll to produce a curve of sea level change for the neogene

numerical modeling of the growth and drowning of hawaiian coral reefs during the last two glacial cycles 0 250 kyr 1 drowned coral reefs on rapidly subsiding margins possess a unique archive of sea level and climate changes generally unavailable from stable or uplifting margins using available field observations and sedimentary radiometric age and numerical modeling data we propose a new model of submerged reef development around hawaii during the last two glacial cycles 250 kyr this model provides a quantitative predictive stratigraphy for the reefs that we argue if drilled will yield new information on sea level and climate changes as well as coral reef response over the last 250 kyr comparing the observational and numerical modeling data combined with sensitivity testing we present our best case scenario for the evolution of the drowned lowstand reefs now at 400 h2 and 150 m h1 we find that growth rates of 2 5 2 85 m kyr for the main shallow reef building facies a subsidence rate of 2 5 m kyr and a variable basement substrate configuration best explain the observational data modeling of the internal stratigraphic succession of the reefs shows that the number and thickness of shallow reef units as well as the frequency and duration of subaerial exposure and reef drowning events are sensitive to the frequency and amplitude of eustatic sea level variations but not the rate of subaerial erosion h2 and h1 initiated growth during stable eustatic sea level conditions during highstands circa 222 ka mis7 and circa 126 ka mis5e respectively both h2 and h1 have a long and complex growth history growing episodically for 90 kyr precessional 20 kyr and higher frequency suborbital eustatic sea level fluctuations dominate with each reef experiencing repeated but brief 5 10 kyr drowning and subaerial exposure producing a complex layer cake stratigraphy of shallow 0 30 m coral reef units separated by either subaerial exposure horizons or thin intermediate 30 60 m coralgal units final drowning of h2 and h1 occurs during the penultimate 133 134 ka and last deglaciation 12 14 ka these findings are consistent with available age data and qualitative predictions of previous studies around hawaii

new constraints on the origin of the australian great barrier reef results from an international project of deep coring two new boreholes provide the first direct evidence of the age of the australian great barrier reef an inner shelf sequence total depth 86 m basal age 210 40 ka comprises a dominantly siliciclastic unit thickness 52 86 m overlain by four carbonate units total thickness 0 34 m a shelf edge and slope sequence total depth 210 m reveals three major sections 1 a lower section of resedimented flows deposited on a lower slope 2 a mid section including intervals of corals rhodoliths and calcarenites with low angle graded laminae and 3 an upper section of four shelf margin coral reef units separated by karst surfaces bearing paleosols sr isotope and magnetostratigraphic data indicate that the central great barrier reef is relatively young post bruhnes matuyama boundary time and our best estimate for the onset of reef growth on the outer barrier system is ca 600 280 ka this date suggests that reef initiation may have been related to the onset of full eccentricity dominated glacio eustatic sea level oscillation as inferred from large amplitude saw tooth 100 k y 18o cycles after marine isotope stage 17 rather than to some regional environmental parameter a major question raised by our study is whether reef margins globally display a similar growth history the possibility of a global reef initiation event has important implications for basin to shelf partitioning of caco3 atmospheric carbon dioxide levels and global temperature change during quaternary time

comparison of color chemical and mineralogical compositions of mine drainage sediments to pigment forty three untreated and actively and passively wetland treated coal mine drainage sediments and five yellow red pigments were characterized using x ray fluorescence fusion inductively coupled plasma atomic emission spectroscopy x ray diffraction and tristimulus colorimeter primary crystalline iron bearing phases were goethite and lepidocrocite and iron phases converted to hematite upon heating quartz was nearly ubiquitous except for synthetic pigments gypsum bassinite calcite and ettringite were found in active treatment sediments iron concentrations from highest to lowest were synthetic pigment wetland sediment natural pigment active treatment untreated sediments varied more widely and manganese was highest in actively treated sediments loss on ignition was highest for passively treated sediments no clear trends were observed between quantified color parameters l a b and redness index and chemical compositions because sediments from passive treatment are similar in chemistry mineralogy and color to natural pigments the mine drainage sediments may be an untapped resource for pigment

a fossil coral perspective on western tropical pacific climate 350 ka 1 the nature of tropical climate variability 350 ka is addressed using 18o and sr ca records from a modern and a fossil coral from vanuatu southwestern tropical pacific ocean modern el nino events at vanuatu produce positive coral 18o and sr ca anomalies similar anomalies observed in the fossil coral records suggest that el nino was operative 350 kyr ago seasonal variations in coral sr ca a sea surface temperature sst proxy have the same amplitude in both corals whereas seasonal 18o variations are smaller in the fossil coral than in the modern coral this is consistent with displacement of the south pacific convergence zone toward the southwest during the boreal summer 350 ka mathematical modeling results preclude warmer sst and higher sss at vanuatu during this time but permit the surface ocean to be 2 c cooler and 0 2 psu fresher than today assessing the potential of variations in late quaternary seawater sr ca remains the largest obstacle to accurately reconstructing tropical sst using pristine fossil corals

sedimentology of rocky shorelines 4 coarse gravel lithofacies molluscan biofacies and the stratigraphic and eustatic records in the type area of the pleistocene hulopoe gravel lanai hawaii abstract during the pleistocene the south flank of lanai was the site of repeated erosion and deposition as a consequence of glacio eustasy superimposed on tectono isostasy throughout this time terrigenous and bioclastic gravel was generated along mainly rocky shorelines gravelly sediment was deposited in topographically low areas of the shoreface and inner shelf that later were uplifted isostatically the sedimentary lithofacies and biofacies in these deposits are distinctive but they represent a deposystem and suite of environments that hitherto have not been studied systematically these unrecognised circumstances have fuelled controversies about the nature and significance of the hulopoe gravel most notably the claim that it represents a mega tsunami deposit the hulopoe gravel in its type area displays a lithofacies succession that encompasses a complete disconformity bounded transgressive regressive cycle on a sand poor rocky shoreline this succession incorporates not only a distinctive vertical assemblage of rocky shoreline litho and biofacies but also internal disconformities that record episodes of erosion and non deposition during shoreline migration repetition of the lithofacies succession imparts overall stratigraphic order to the hulopoe gravel four unconformity bounded transgressive regressive cycles correspond to eustatic highstands of oxygen isotope stages 5 and 7 superimposed on continuing tectono isostatic uplift driven by growth of the island of hawaii this study of the hulopoe gravel demonstrates that the sedimentary record of mixed volcaniclastic carbonate depositional systems developed on rocky shorelines of tropical and subtropical oceanic island coasts can be preserved this record may include depositional products of both transgressive and regressive shorelines although tsunami and giant submarine landslides are known to occur in the hawaiian islands deposits and features that result from tsunami inundation above the shoreline such as might be expected from landslide related mega tsunami have not been recognised in the type area of the hulopoe gravel rocky palaeoshoreline records on oceanic volcanic islands may yield oceanographic and climatic clues that complement data obtained from other palaeoshoreline types

sedimentology of rocky shorelines 5 the marine samples at 326m from stearns swale lanai hawaiʻi and their paleo environmental and sedimentary process implications abstract fossiliferous gravels on lanai one of the smaller hawaiian islands are known collectively as the hulopoe gravel since 1984 several workers have attributed these gravels to deposition from the run ups and retreats of mega tsunami other workers before and since have interpreted the gravels as rocky shoreline deposits exposed by island uplift the existence of harold stearns makana paleoshoreline on lanai at 326 365 m elevation is particularly controversial in 1936 stearns collected some marine molluscan fossils from a site at 326 m elevation on the southern slope of lanai now known as stearns swale details of the site the fossils and his installed markers were recorded in his field note book now held by the us geological survey in honolulu the fossils were lodged in the national museum of natural history in washington d c during ww ii the 326 m site became a military installation and stearns markers and any remaining fossils were destroyed we have examined stearns notebook the 326 m site and the fossils two types of sediment adhere to the fossils a weakly cemented well rounded biocalcarenite grainstones with minor subrounded basalt fragments b calcite cemented sub rounded to well rounded volcanic litharenite or lithrudite with some bioclasts the fossil molluscs and the bioclasts in the adhering sands represent organisms typical of hawaiian rocky shorelines and adjacent submarine slopes these features are consistent with 1 deposition of the sediments on or closely overlying an unconformity surface cut in basalt bedrock in the vicinity of a rocky shoreline they are also consistent with 2 derivation of the materials from rocky shorelines or shorefaces at lower elevations and their transport up slope by waves generated by a category 5 hurricane or by a mega tsunami we prefer the first scenario as lanai s vertical mobility is indicated by at least ten topographically distinct shoreline related deposits located at various elevations on or adjacent to lanai including six submerged terraces on its western flank

estimating the longevity of limestone drains in treating acid mine drainage containing high concentrations of iron abstract limestone drains are often implemented in the treatment of acid mine drainage amd but when the amd contains high levels of dissolved fe their lifetime is dependent on the rate of precipitation of fe hydroxide on the limestone surface this study used a small scale laboratory experiment to define the longevity of a limestone drain by determining the thickness of the fe coating encapsulating the limestone particles when the system lost its maximum neutralising potential synthetic amd 100 mg l fe ph 4 4 8 was pumped through a column containing limestone particles for 1110 h when the effluent ph had dropped from a maximum of 6 45 4 9 the decline in neutralisation during the experiment was due to the formation of fe hydroxide coatings on the limestone grains these coatings are composed of lepidocrocite goethite in three distinct layers an initial thick porous orange layer overlain by a dense dark brown crust succeeded by a layer of loosely bound porous orange globules after 744 h a marked increase in the rate of ph decline occurred and the system was regarded as having effectively failed at this time the fe hydroxide crust effectively encapsulated the limestone grains forming a diffusion barrier that slowed down limestone dissolution between the coating and the limestone substrate was a 60 m wide void so that agitation of the limestone sample would readily remove the coating from the limestone surface in the experimental system the time for sufficient fe hydroxide to precipitate on the limestone to cause a distinct decline in the rate of neutralisation was defined by t years surface area m 2 4 4 fraction fe retained in system fe 2 mg l flowrate l h at this time the limestone in the drain would need to be replaced or mechanically agitated to remove the fe hydroxide coating to allow the system to continue functioning at its maximum potential application of this formula to the field situation shows that even when the influent fe concentrations are moderately high limestone drains will continue to function well for one to several years thus passive limestone systems can be used in amd treatment when the influent fe concentration is considerably greater than 1 mg l the currently recommended limit particularly given that the fe precipitates armouring the limestone grains may be loosely bound and relatively easily dislodged therefore limestone drains are more widely applicable than presently realised

subsidence and volcanism of the haleakala ridge hawaii abstract side looking sonar gloria mapping has revealed a series of four arcuate bands of high sonic backscatter on the crest of the haleakala ridge a major rift zone ridge extending 135 km east of the island of maui dredge recovery indicates that the shallowest of these bands is a drowned coral reef and the deeper bands are also inferred to be coral reefs the reefs occur above a prominent submarine bench 1500 2500 m deep on the ridge h terrace that marks the shoreline at the end of vigorous shield building of haleakala volcano when lava flows ceased crossing and reworking the shoreline since their growth these reefs have subsided as much as 2200 m and have tilted systematically about 20 m km southward as a result of post reef volcanic loading on the island of hawaii whose center of mass is about directly south of the haleakala ridge the 234u 238u age of the dredged coral is 750 13 ka in reasonable agreement with an age of 850 ka for the underlying h terrace previously estimated from its relationship to other dated reefs to the southwest basalt glass fragments dredged from the haleakala ridge below the h terrace are tholeiitic and contain high sulfur indicative of eruption in water deeper than 200 m basalt glass fragments associated with the reefs above the h terrace are dominantly tholeiitic and contain intermediate sulfur contents indicative of subaqueous eruption in shallow near shore conditions one alkalic glass fragment was recovered above the h terrace these relations indicate that the morphologic end of shield building as recorded by construction of the h terrace was not accompanyed by a change from tholeiitic to alkalic basalt instead tholeiite eruptions continued for some time before the erupted lava became alkalic

sr isotopic variation in shallow water carbonate sequences stratigraphic chronostratigraphic and eustatic implications of the record at enewetak atoll sr isotope data from two boreholes within the lagoon at enewetak atoll have been used to evaluate the use of such data to correlate date and monitor sea level change in shallow water carbonate sequences correlative stratigraphic intervals of relatively invariant 87sr separated by abrupt transitions to lower 87sr with increasing depth are recognized in both boreholes conversion of 87sr values to age via calibration with the seawater 87sr trend with age indicates that correlative and synchronous deposition of atoll sediments occurred at 0 4 1 2 and 2 1 ma in contrast a 5 m y hiatus is recognized in one borehole but not the other sr isotope stratigraphy sis is a powerful stratigraphic and chronostratigraphic tool in shallow water carbonate sequences only when significant secular variation of 87sr occurs and retention of depositional 87sr values is demonstrated the latter is best demonstrated when 87sr data are integrated with 18o 13c sr content data and petrographic observations several diagenetically altered intervals have greater 87sr values low 13c values and low sr ca ratios relative to adjacent intervals a combination that is consistent with open system meteoric diagenesis calcite cements from these intervals have early pleistocene 1 2 ma 87sr values despite their occurrence well within the late pliocene 2 1 ma sequence thus local sedimentological and diagenetic processes have produced intralagoon variability in the sis of the two boreholes complicating subsurface stratigraphic correlations the occurrence of anomalously young calcite cement relative to adjacent limestone is a direct response of the interaction of sea level change and meteoric phreatic diagenesis whereby overlying metastable carbonates with greater 87sr values are dissolved during periods of atoll emergence and sea level lowstand liberating sr and soil gas co2 to the pore fluid which is then incorporated into downflow meteoric phreatic diagenetic calcite the stratigraphic relation between the sites of carbonate dissolution and diagenetic calcite precipitation suggest an early pleistocene 1 2 ma sea level fall of between 34 and 64 m moreover the stratigraphic position and inferred age of paleophreatic lens calcite when backtracked for subsidence suggest that early pleistocene 1 2 ma sea level was 72 81 m range of 60 100 m below present sea level the enewetak record of early pleistocene sea level lowstand elevation agrees reasonably well with proxy sea level records inferred from sequence stratigraphy and deep sea foraminiferal 18o data however the enewetak record of the amplitude of early pleistocene sea level change is more consistent with the deep sea foraminiferal 18o proxy than the sequence stratigraphy proxy

dissolution of calcitic marble and dolomitic rock in high iron concentrated acid mine drainage application to anoxic limestone drains oxidation of sulphide mining waste can generate acid mine drainage amd that has the potential to seriously affect the ecosystems acid mine drainage is characterised by a high acidity high concentrations of sulphates and metals to reduce the environmental impacts due to amd neutralisation using limestone drains is an option proposed in the literature and used around the world the present study focuses on the influence of the carbonate rock mineralogy and their particle size on the neutralising capacity the tests were performed in two different anoxic conditions in batch reactors and in columns having a hydraulic retention time of 15 h the results showed that the neutralisation capacity of calcite was more important than for dolomitic rock and smaller particle size gave higher alkalinity production fine calcite dissolved faster in contact with amd a characterization of metal precipitate in sludge and in limestone coating was performed and demonstrated that gypsum lepidocrocite and goethite were the predominant secondary minerals to be formed finally this study underlines that anoxic limestone drain cannot be used alone to treat high iron concentrated amd

characterization of limestone reacted with acid mine drainage in a pulsed limestone bed treatment system at the friendship hill national historical site pennsylvania usa abstract armoring of limestone is a common cause of failure in limestone based acid mine drainage amd treatment systems limestone is the least expensive material available for acid neutralization but is not typically recommended for highly acidic fe rich waters due to armoring with fe iii oxyhydroxide coatings a new amd treatment technology that uses co2 in a pulsed limestone bed reactor minimizes armor formation and enhances limestone reaction with amd limestone was characterized before and after treatment with constant flow and with the new pulsed limestone bed process using amd from an inactive coal mine in pennsylvania ph 2 9 fe 150 mg l acidity 1000 mg l caco3 in constant flow experiments limestone is completely armored with reddish colored ochre within 48 h of contact in a fluidized bed reactor effluent ph initially increased from the inflow ph of 2 9 to over 7 but then decreased to 6 during operation limestone removed from a pulsed bed pilot plant is a mixture of unarmored rounded and etched limestone grains and partially armored limestone and refractory mineral grains dolomite pyrite the 30 of the residual grains in the pulsed flow reactor that are armored have thicker 50 to 100 m more aluminous coatings and lack the gypsum rind that develops in the constant flow experiment aluminium rich zones developed in the interior parts of armor rims in both the constant flow and pulsed limestone bed experiments in response to ph changes at the solid solution interface