the early permian floras of prince edward island canada differentiating global from local effects of climate change new permian plant specimens are described from prince edward island canada they include attached specimens of leaf and stem genera walchia and tylodendron enabling reconstruction of this early permian conifer al though poorly preserved the study of these floras extends our knowledge of diversity and climate conditions in the re gion by placing these findings in a broader stratigraphic and geographic framework we can document the phytogeographic and climate trends through the carboniferous and permian in the maritimes basin combined data on temporal trends in climate sensitive sediments as well as macrofloral and microfloral diversities generally match the independently derived paleolatitudinal estimates these show the region migrating from the southern subtropics across the equator and into the northern subtropics between the early carboniferous and early permian evaporites and pedogenic carbonates together with low diversity floras match its subtropical position in the early carboniferous in contrast coals are present in the late carboniferous accompanied by high diversity macro and microfloral remains when the region was on or near the equator however the subsequent transition to pedogenic carbonates eolian sands and lower diversity floras is not matched by significant poleward latitudinal motion we ascribe these changes to a de crease in moisture availability as transgressions of epeiric seas became less frequent and finally stopped altogether causing an increase of continentality in euramerica resume cet article decrit de nouveaux specimens de plantes datant du permien provenant de l ile du prince edouard canada ils comprennent des specimens de feuilles et de tiges rattachees de genre walchia et tylodendron permettant la reconstruction de ce conifere du permien precoce bien que ces flores soient mal preservees leur etude etend nos connaissances de la diversite et des conditions climatiques de la region en placant ces decouvertes dans un cadre stratigraphique et geographique plus large nous pouvons documenter les tendances phytogeographiques et clima tiques du carbonifere et du permien dans le bassin des maritimes des donnees combinees sur les tendances temporel les dans des sediments sensibles au climat et des diversites relatives a la macro et a la microflore concordent generalement avec les estimations de paleoaltitude derivees de facon independante ces donnees montrent qu entre le carbonifere precoce et le permien precoce il y eut une migration des regions subtropicales meridionales par dela l equateur vers les regions subtropicales septentrionales des evaporites et des carbonates pedogenetiques avec des flo res faiblement diversifiees correspondent a sa position subtropicale au carbonifere precoce par contre on retrouve des charbons au carbonifere tardif accompagnes de restes de macro et de microflores grandement diversifiees lorsque la region etait a ou pres de l equateur toutefois la transition subsequente a des carbonates pedogenetiques a des sables eoliens et a une diversite florale moindre n est pas correlee par un mouvement meridien significatif vers le pole nous attribuons ces changements a une reduction de l humidite disponible alors que les transgressions des mers epicontinen tales devenaient de moins en moins frequentes et qu elles ont finalement cesse tout a fait causant une augmentation de la continentalite en euramerique

reconstructed tree fern alethopteris zeilleri carboniferous medullosales abstract from a smaller open pit area in the roof shale of the basal cantabrian coal seam in sydney coalfield cape breton island nova scotia canada large amounts of the pteridosperm foliage alethopteris zeilleri ragot were found this foliage is associated with abundant naked medullosalean axes and dichotomies of varying sizes up to 0 80 m long cauline structures 0 90 m and 1 3 m long detached ovules assigned to pachytesta incrassata brongniart rare male pollen organs of the type dolerotheca halle rooted tree ferns in life position and one specimen each of a juvenile medullosalean frond and root mantle the fossils are compression impression preserved and the foliage yielded thickly cutinized cuticles with unoriented cells 57 103 by 27 57 m in intercostal fields ultimate rachises and abaxial surfaces excluding costal fields show a mixture of simple and complexly branched trichomes and two different structural bases these together with fractal dimensionality of curvatures of anticlinal walls in intercostal fields have taxonomic potential for alethopterids the finds suggest reconstructing a zeilleri ragot as a tree 5 7 m high that bore both p incrassata brongniart and dolerotheca type fructifications its habitat was low land coastal plains in the pennsylvanian coal swamps of ancestral sydney coalfield

improved global surface currents from the merging of altimetry and sea surface temperature data abstract six years of surface velocities have been calculated over the global ocean by combining altimeter derived geostrophic velocities and sea surface temperature sst data the method is based on the inversion for the velocity of the heat conservation equation using the altimeter velocities as background by accurately prescribing the error both on the background velocities and on the forcing term heat fluxes the altimeter background velocities are successfully improved in areas characterized by strong sst gradients and remain unchanged in low sst gradient regions where by construction no additional information may be brought by the sst field this allows us to provide for the first time a global field of surface velocities from the merging of altimetry and sst both the spatial and temporal resolution of the altimeter derived velocities is enhanced by the sst information validation is performed through comparison to in situ drifting buoy velocities major improvements 10 20 globally up to 35 locally are obtained on the meridional component of the velocity and in the equatorial band due to the large uncertainty on the heat fluxes and the spatio temporal resolution of the input datasets the high frequency ageostrophic components of the circulation is hardly resolved by the method and outside the equatorial band improvements are mainly on the geostrophic component it is shown that the level of accuracy obtained by combining altimeter velocities based on a two satellite configuration and microwave sst data is equivalent or higher to the one from a four altimeter constellation in western boundary currents this opens the perspective for a systematic use of the method to improve the altimeter derived surface velocities over the 1993 2001 period for which only 2 altimeters have been flying simultaneously finally over the recent years the use of higher resolution sst products based on both microwave and infrared measurements leads to further enhancement of the accuracy of the altimeter velocities on both the zonal and the meridional component in strong sst gradients areas

palaeofloristics of middle pennsylvanian lyginopteridaleans in variscan euramerica abstract during bolsovian times the lyginopteridales spermatophyta had a very similar biogeographical distribution across variscan euramerica to that revealed by the medullosales spermatophyta however this biogeographical pattern progressively breaks down during asturian and cantabrian times as the species diversity of the order declines dramatically this decline was probably the result of being out competed for resources by the reproductively more sophisticated callistophytales there remains little direct evidence for marked climate changing occurring until middle or late cantabrian times

chemometric study of functional groups in different layers of trigonocarpus grandis ovules pennsylvanian seed fern canada abstract we examined four dispersed coalified ovules trigonocarpus grandis of medullosalean seed fern affinity from the late pennsylvanian age sydney coalfield canada which represent the larger type of the 7 8 cm trigonocarpalean form species at first glance it appears that the ovules are preserved like the usual carboniferous foliar compressions i e one coalified layer with one preserved anatomical tissue the cuticle however careful sample preparation uncovered at least three coalified layers and schulze s oxidative maceration process which dissolves the coalified material revealed several tissue layers altogether eight sample forms were defined i coalified layer ii cuticle a iii cupric vitrain iv vitrain v cupric vi cuticle b vii alkaline solution and viii added coal seam material the purpose of the study was twofold first to systematically analyze the forms by way of fourier transform infrared ftir spectrometry to fill a gap in chemical information that exits for coalified trigonocarpalean ovules of carboniferous seed ferns second to use principal component analysis to focus on groupings as a function of chemical structure functional groups and to assess the different fossil forms in terms of ftir chemical parameters based on a 8 49 data matrix results include distinction among the three coaly sample forms coalified layer i cupric vitrain iii and cupric v based mainly but not exclusively on differences in carbonyl content as well as length and branching of the polymethylenic chains important to note is the high aliphatic content of the cuticles as a signature of the biomacromolecules cutan cutin in particular new insights into the structure of the original ovule are presented and differences in chemistry are mainly a result of the complex structure of the precursor plant organ

a comparative analysis of some late carboniferous basins of variscan europe vegetation diversity and pattern changes and their relation to tectono sedimentary histories are compared between selected euramerican late palaeozoic coalfields to understand better the controls on the dynamics of the pennsylvanian terrestrial ecosystems and to demonstrate the problems with comparing data from various basins the analysis is based on data from the following basins of different geotectonic and palaeogeographical positions the cratonic pennines basin the foreland south wales and upper silesia basins and the fault related intra sudetic and central and western bohemia basins the analysis indicates that complex factors are responsible for changes in plant diversity and vegetation patterns these are related to climate tectonics preservation potential sampling biases and the current state of revision of the flora in each basin plant diversity patterns in the basins differ because of local controls and or the character and detail of the available data maximum diversity varies among the basins within the langsettian and duckmantian substages two apparent step like drops in diversity were detected within coal bearing strata of most basins at the duckmantian bolsovian boundary and at the bolsovian asturian boundary further and more prominent falls are related to transitions from coal bearing to non coal bearing mostly red bed strata or vice versa during stephanian times interpretation of climatic signals recorded in the sedimentary successions indicates that westphalian and middle stephanian times were wet intervals whereas early and late stephanian times were drier

functional groups and elemental analyses of cuticular morphotypes of cordaites principalis germar geinitz carboniferous maritimes basin canada well preserved cuticles were isolated from cordaites principalis germar geinitz leaf compressions i e foliage from extinct gymnosperm trees coniferophyta order cordaitales the specimens were collected from the sydney stellarton and bay st george subbasins of the once extensive carboniferous maritimes basin of atlantic canada fourier transformation of infrared spectra ftir and elemental analyses indicate that the ca 300 306 million year old fossil cuticles share many of the functional groups observed in modern cuticles the similarities of the functional groups in each of the three cuticular morphotypes studied support the inclusion into a single cordaite leaf taxon i e c principalis germar confirming previous morphological investigations vitrinite reflectance measurements on coal seams in close proximity to the fossil bearing sediments reveal that the bay st george sample site has the lowest thermal maturity whereas the sites in sydney and stellarton are more mature ir absorption and elemental analyses of the cordaite compressions corroborate this trend which suggests that the coalified mesophyll in the leaves follows a maturation path similar to that of vitrinite comparison of functional groups of the cordaite cuticles with those from certain pteridosperms previously studied from the y1 sydney subbasin shows that in the cordaite cuticles highly conjugated c o 1632 cm bands dominate over carbonyl stretch that characterizes the pteridosperm cuticles the differences demonstrate the potential of chemotaxonomy as a valuable tool to assist distinguishing between carboniferous plant fossil groups published by elsevier science b v

latest mid pennsylvanian tree fern forests in retrograding coastal plain deposits sydney mines formation nova scotia canada a latest mid pennsylvanian early cantabrian tree fern forest is reported from cape breton island nova scotia the fossil forest is rooted below the point aconi coal seam of the sydney mines formation at cranberry head the tree ferns are preserved in the deposits of a coastal plain subject to brackish incursions they were constructed of psaronid type trunks and massive pecopterid fronds and locally intergrew with sigillarian lycopsids neuropterid pteridosperms and calamiteans basal stump diameter measurements including the root mantle range from 12 to 89 cm indicating that the ferns were mostly large forest trees rather than shrubs stump distribution measurements on palaeosols indicate that localized patches of tree fern dominated forest attained densities of c 3850 trees per hectare when scaled up to standard forestry units much denser than typical mid pennsylvanian lycopsid forests tree ferns dominantly grew in aggrading floodbasin settings and a few of the largest trees show evidence for post burial regeneration being approximately coeval with the late mid pennsylvanian extinction event which resulted in tree fern forests rising to dominate tropical lowlands for the first time the cranberry head fossil forests provide insight into community composition and structure during a critical phase of ecosystem reorganization

esr dating of the fossil hominid cranium from petralona cave greece the age of the hominid cranium discovered in 1960 in a limestone cave near petralona greece is a continuing cause of controversy the age of the skull which was apparently encrusted by brown calcite soon after the death of the individual concerned has been variously estimated at between 70 0001 and 700 0002 yr here we show using electron spin resonance esr measurements of the calcite encrustation and of bone fragments that the age of the petralona hominid lies between 160 000 and 240 000 yr we also demonstrate by trace element analysis that the composition of the calcite encrustation is the same as that of the very top of the travertine floor

the signature of mesoscale eddies on the air sea turbulent heat fluxes in the south atlantic ocean abstract by collocating 10 years 1999 2009 of remotely sensed surface turbulent heat uxes withsatellite altimetry data we investigate the impact of oceanic mesoscale eddies on the latent and sensibleheat uxesinthesouthatlanticocean instronglyenergeticregions suchasthebrazil malvinascon uenceand the agulhas current retro ection eddies explain up to 20 of the total variance in the surfaceturbulent heat uxes with averaged anomalies of 10 20 w m 2 cyclonic anticyclonic respectively eddies are associated with negative positive heat ux anomalies that tend to cool warm the marineatmospheric boundary layer a composite analysis of the turbulent heat ux anomalies inside the eddiesrevealsadirectrelationshipbetweeneddyamplitudeandtheintensityofsuchanomalies inaddition theseanomaliesarestrongerneartheeddycenter decayingradiallytoreachminimumvaluesoutsidetheeddies 1 introduction the ocean atmosphere system is primarily turbulent in the mesoscale band oceanic eddies play a crucialrole in transporting heat salt momentum and biogeochemical tr acersalongtheirtrajectories signi cantlyimpactingtheoceandynamicsand uxes olson 1991 wunsch 1999 morrowetal 2003 mesoscaleeddiesare coherent rotating features with typical horizontal scales of 50 300 km and time scales ranging fromweeks to months cheltonetal 2011a theyalsoexhibitparticularthermohalineverticalstructuresassoci ated with strong dynamical perturbations of the density and pressure elds olson 1991 chaigneau et al 2011 kurian et al 2011 zhang et al 2013 roullet et al 2014 these perturbations extend up to the seasurface leadingtoanomaliesonseasurfaceheight seasurfacetemperature sst andwindstress amongothers frengeretal 2013 souzaetal 2014 asaresult itisexpectedthateddiesimpacttheair sea uxesandtheoverlayingatmosphericcirculation frengeretal 2013 the turbulent latent lhf and sensible shf heat uxes are the primary processes by which the oceanreleases heat to the atmosphere cayan 1992 both the lhf and shf can be derived from bulk formulaelinking oceanic and atmospheric parameters such as air speci c humidity sst and wind speed to theheat exchanged at the air sea interface liu et al 1979 fairall et al 2003 large and yeager 2009 theanomalies caused by mesoscale eddies in some of these parameters have been recently investigated e g white and annis 2003 hausmann and czaja 2012 frenger et al 2013 souza et al 2014 chelton and xie 2010 although there is ample evidence that oceanic mesoscale features have a signi cant impact onair seaproperties thereisstillalackofknowledgeabouttheirsignatureonthesurfaceturbulentheat uxesandtheirpotentialcontributionstothenetsurfaceheatbudget the recent release of daily satellite based data from the french research institute for exploitation of thesea ifremer bentamy et al 2013 has su cient resolution to estimate the lhf and shf associatedwith mesoscale processes the present work merges satellite altimetry sea level anomaly sla data withremotely sensed surface heat uxes to investigate the impact of mesoscale ocean eddies on the lhf andshfinthesouthatlanticocean sa the sa encompasses both quiescent areas and two regions of intense energetic variability associated withthe presence of large mesoscale eddies figure 1a namely the agulhas current retro ection agr olsonand evans 1986 goni et al 1997 andthebrazil malvinascon uence bmc garzoli and garra o 1989 olson et al 1988 more speci cally we aim i to assess the mean lhf and shf anomalies induced bycyclonicandanticycloniceddiesinthesa ii todescribethespatialvariationsoftheheat uxanomaliesinvillasboasetal

esr dating in quaternary geology abstract electron spin resonance esr a relatively new dating technique was first suggested by zeller et al 1967 zeller 1968 and levy 1968 it has made substantial progress in frequent applications in the last few years esr dating is based on the direct measurement of the amount of radiation induced paramagnetic electrons trapped in crystal defects these free electrons were generated by alpha beta and gamma radiation of natural radioelements e g u th k and have accumulated in the minerals over geologic time the esr age is obtained by dividing the total amount of accumulated radiation dose archaeological dose ad by the dose per year annual dose this review comprises four major parts the principles of the method the determination of the archaeological dose ad the determination of the annual dose and a compilation of datable materials several questions remain the evaluation of the ad the determination of the annual dose and particularly with respect to the nature and stability of the electron traps used for dating

palynological evidence for pennsylvanian extra basinal vegetation in atlantic canada abstract pollen preserved in latest westphalian and early stephanian clastic deposits of the sydney coalfield cape breton island suggest that there were zones of different vegetational habitats surrounding the wetlands where the coal forming peat was formed on the margins of the wetlands was a narrow band with large cordaitanthacean trees this was surrounded by occasionally dry9 habitats supporting schuetzia plants ruflorioid plants and aethophyllum like herbaceous conifers around this were mesic or seasonally dry habitats dominated by walchian conifers and disaccate producing peltasperms these in turn were surrounded by xeric or seasonally wet habitats dominated by ullmanniacean like conifers cycads and monosaccate producing peltasperms during latest westphalian and early stephanian times the mesic and xeric habitats encroached nearer the wetlands although the vegetation of the wetlands themselves remained essentially unaffected this vegetation change was not a response to climate change but probably to changing drainage patterns and topography in the surrounding hinterland the florinites producing cordaitanthaceans appear not to have been upland trees as previously suggested but occupied mainly coastal habitats or riparian habitats on the margins of the wetlands

storm track response to oceanic eddies in idealized atmospheric simulations abstractlarge scale oceanic fronts such as in western boundary currents have been shown to play an important role in the dynamics of atmospheric storm tracks little is known about the influence

ecological changes in pennsylvanian asturian and early cantabrian coal floras inferred from lycophyte microspore abundances abstract the distribution and relative amounts of six genera of lycophyte microspores lycospora densosporites crassispora cirratriradites endosporites and cadiospora are compared in the pennsylvanian coals from the dobrudzha and forest of dean coalfields clastic sediments from the glace bay borehole in the cape breton coalfield and the southern crop of the south wales coalfield inverse relationships are shown between lycospora and densosporites and between lycospora and crassispora in samples from all of the coalfields the changes in microspore assemblages suggest there were at least five different communities of lycophyte plants growing in the pennsylvanian swamps changes in microspore assemblages at the asturian cantabrian boundary mirror the previously described macrofloral changes at this time

a sedimentological overview of the coal bearing morien group pennsylvanian sydney basin nova scotia canada the onshore part of the sydney basin nova scotia contains a 2 km fining upward coal bearing succession the pennsylvanian morien group facies analysis indicates an upward change in depositional

vertical structure of mesoscale eddies in the eastern south pacific ocean a composite analysis from altimetry and argo profiling floats 1 the mean vertical structure of mesoscale eddies in the peru chile current system is investigated by combining the historical records of argo float profiles and satellite altimetry data a composite average of 420 526 profiles acquired by argo floats that surfaced into cyclonic anticyclonic mesoscale eddies allowed constructing the mean three dimensional eddy structure of the eastern south pacific ocean key differences in their thermohaline vertical structure were revealed the core of cyclonic eddies ces is centered at 150 m depth within the 25 2 26 0 kg m 3 potential density layer corresponding to the thermocline in contrast the core of the anticyclonic eddies aes is located below the thermocline at 400 m depth impacting the 26 0 26 8 kg m 3 density layer this difference was attributed to the mechanisms involved in the eddy formation while intrathermocline ces would be formed by instabilities of the surface equatorward coastal currents the subthermocline aes are likely to be shed by the subsurface poleward peru chile undercurrent in the eddy core maximum temperature and salinity anomalies are of 1 c and 0 1 with positive negative values for aes ces this study also provides new insight into the potential impact of mesoscale eddies for the cross shore transport of heat and salt in the eastern south pacific considering only the fraction of the water column associated with the fluid trapped within the eddies each ce and ae has a typical volume anomaly flux of 0 1 sv and yields to a heat and salt transport anomaly of 1 3 1011 w and 3 8 103 kg s 1 respectively

an introduction to the rhynie chert the terrestrialization of life has profoundly affected the biosphere geosphere and atmosphere and the geological magazine has published key works charting the development of our understanding of this process integral to this understanding and featuring in one of the geological magazine publications is the devonian rhynie chert konservat lagerstatte located in aberdeenshire scotland here we provide a review of the work on this important early terrestrial deposit to date we begin by highlighting contributions of note in the geological magazine improving understanding of terrestrialization and palaeozoic terrestrial ecosystems we then introduce the rhynie chert the review highlights its geological setting the caledonian context of the rhynie basin and its nature at the time of deposition of the cherts which host its famous fossils there follows an introduction to the development of the half graben in which the cherts and host sediments were deposited the palaeoenvironment this represented and the taphonomy of the fossils themselves we subsequently provide an overview of the mineralization and geochemistry of the deposit and then the fossils found within the rhynie chert these include six plant genera which continue to provide significant insights into the evolution of life on land a range of different fungi with recent work starting to probe plant fungus interactions lichens amoebae and a range of unicellular eukaryotes and prokaryotes algae and cyanobacteria and finally a range of both aquatic and terrestrial arthropods through continued study coupled with methodological advances rhynie fossils will continue to provide unique insights into early life on land

the influence of nonlinear mesoscale eddies on near surface oceanic chlorophyll oceanic rossby waves have been widely invoked as a mechanism for large scale variability of chlorophyll chl observed from satellites high resolution satellite altimeter measurements have recently revealed that sea surface height ssh features previously interpreted as linear rossby waves are nonlinear mesoscale coherent structures referred to here as eddies we analyze 10 years of measurements of these ssh fields and concurrent satellite measurements of upper ocean chl to show that these eddies exert a strong influence on the chl field thus requiring reassessment of the mechanism for the observed covariability of ssh and chl on time scales longer than 2 to 3 weeks the dominant mechanism is shown to be eddy induced horizontal advection of chl by the rotational velocities of the eddies

the relationship between euramerican and cathaysian tropical floras in the late palaeozoic palaeobiogeographical and palaeogeographical implications abstract wetland plant communities persisted though much of the pennsylvanian in euramerica and are the dominant coal forming vegetation in this region distribution of these floras show a dramatic decline at the end of the carboniferous with many of the plant genera and species becoming extinct by the onset of the permian this has been correlated with climate change and in particular aridification associated with northwards plate motion and euramerica moving into the doldrums but is also associated with the variscan orogeny and forefront destroying large areas of formerly lowland basinal settings other factors may include pennsylvanian glaciations as evidenced by cyclothem and rhythmical deposition in lowlying wetland settings and change in eustatic base level evidence from euramerica demonstrates extinction of this kind of wetland biota by the earliest permian and the development of drier floras including conifer dominated assemblages however new data from other parts of the world most notably north china confirm this model and highlight the presence of similar coal swamps ranging from the late pennsylvanian through the permian in this paper we summarise and synthesize recent taxonomic and systematic investigations undertaken on the plant fossils from the pennsylvanian benxi formation the oldest recognised wetland plant community in china and the early permian taiyuan formation the best preserved wetland plant community from china results indicate a remarkable similarity of the pennsylvanian early permian floras of north china with the older assemblages in the pennsylvanian of euramerica and the presence of typical euramerican coal swamp plant families genera and in some cases species in china conclusions include the presence of the ameriosinian phytogeographical realm uniting euramerica and northern cathaysia at this time coal swamps in the permian of north china evolving from a euramerican origin and the dramatic floral turnover at the end of the carboniferous representing a regional event rather than a global extinction episode patterns of plant distribution through this interval have profound implications on established palaeogeographical models and support continental connection between euramerica and cathaysia before the end of the carboniferous contradicting ideas of cathaysian island biogeography and biotic distinction continental connection appears to be related to glacial eustatic low stand and previously shallow marine environments becoming vegetated also important is the fact that in both euramerica and north china the pattern of floristic demise within wetland plant communities are similar to each other implying the same causal mechanisms with plants occupying waterlogged positions being the most severely devastated however ecosystem demise occurred at the end of the carboniferous in euramerica and in the middle permian in north china but in both cases the primary cause was climate change

petrology of selected carbonaceous limestones and shales in late carboniferous coal basins of atlantic canada carbonaceous limestones and shales are associated with coal in late carboniferous alluvial to coastal successions of nova scotia the units are thin 45 km they consist of micrite and or illitic and kaolinitic clay and some contain abundant bivalves ostracodes pyrite up to 11 vol and phosphatic and sideritic nodules trace fossils are scarce to absent the organic material 2 43 toc is characterised as type ii iii and is mainly of terrestrial derivation predominantly vitrinite and sporinite with lamalginite and telalginite as minor constituents vitrinite reflectance measurements indicate immaturity ro 0 5 but are lower than those of associated coals source rock and hydrocarbon recovery potentials are good to very good and the potentials of some units compare favourably with those of alginite rich carboniferous oil shales in adjacent basins the carbonaceous units were deposited in shallow lakes and or interdistributary bays with aerobic to anaerobic bottom waters at times of minimal detrial input

lacustrine stromatolites and algal laminites in a pennsylvanian coal bearing succession near sydney nova scotia canada stromatolitic limestone units in the pennsylvanian morien group near sydney nova scotia occur within mudstones in repetitive fining upward coal bearing sequences interpreted as meandering fluvial cyclothems the fluvial association presence of a non marine fauna and the lack of marine fossils indicate a lacustrine environment for the algal units horizontally laminated and domal forms are present the latter encrusted on oncoids which are attributed to moderate wave agitation the stromatolites occupy a position analogous to the marine bands in paralic coal sequences and represent repetitive lacustrine development within the fluvial cyclothems of the sydney basin

mesoscale eddy detection in satellite imagery of the oceans using the radon transform abstract the present study proposes a new methodology to identify mesoscale eddies that are ubiquitous in the ocean and can be observed in a variety of satellite images our focus is on eddies with mean diameter of 100 500 km the proposed methodology uses an algorithm based on the radon transform the basic premise is that the inverse radon transform of a circularly symmetric feature is angle independent therefore the more constant the radon transform of an image is with respect to the rotation angle the more circularly symmetric the image is although our method is based on circular symmetry it is able to detect non symmetric eddies using a sensitivity parameter that quantifies the deformation our method is effective to determine how circular a feature observed in a satellite image is and suggest whether it is an eddy or not based on geometric criteria a series of tests with synthetic data were performed to assess the sensitivity to spectral content and aspect ratio detectable by the method another sequence of tests was carried out with images of chlorophyll a concentration sea surface temperature and sea surface height in the three cases five areas of 100 50 pixels were selected and filtered with exactly the same algorithm and parameters the two sets of tests indicate that the proposed method was able to identify eddies in a single time series of satellite images and in multiple series of different variables the main advantage of this method in comparison with either automatic ones based on dynamics and geometry or manual methods is its ability to observe eddies in multiple data sets of different variables

satellite observations of mesoscale eddy induced ekman pumping abstractthree mechanisms for self induced ekman pumping in the interiors of mesoscale ocean eddies are investigated the first arises from the surface stress that occurs because of differences between surface wind and ocean velocities resulting in ekman upwelling and downwelling in the cores of anticyclones and cyclones respectively the second mechanism arises from the interaction of the surface stress with the surface current vorticity gradient resulting in dipoles of ekman upwelling and downwelling the third mechanism arises from eddy induced spatial variability of sea surface temperature sst which generates a curl of the stress and therefore ekman pumping in regions of crosswind sst gradients the spatial structures and relative magnitudes of the three contributions to eddy induced ekman pumping are investigated by collocating satellite based measurements of sst geostrophic velocity and surface winds to the interiors of eddies identified from their sea surface height signatures on average e

ftir microspectroscopy of particular liptinite lopinite rich late permian coals from southern china abstract the late permian coals from southern china are unique in their high content of lopinite liptinite and elemental hydrogen and typically produce high yields of tar typical of the late permian coals of southern china the coals used in this study show special petrographic and chemical characteristics as well as significant oil producing potential studies of these coals and of their content of the lopinite maceral will help to explain the genesis of both the lopinite maceral and of the oil producing potential of the coals in this study an ftir spectrometer was used in the standard transmission mode to generate the ir spectra of the whole coal an ftir spectrometer equipped with a microscope in the reflectance mode was used to analyze the chemical structure of individual coal macerals including lopinite vitrinite semifusinite and inertinite the chemical structure of lopinite is characterized by its higher content of longer and less branched aliphatic side chains and distinct c 0 groups the oil producing potential of the coals is attributed to their higher content of lopinite

eddy properties in the california current system 1 eddy detection and tracking algorithms are applied to both satellite altimetry and a high resolution dx 5 km climatological model solution of the u s west coast to study the properties of surface and undercurrent eddies in the california current system eddy properties show remarkable similarity in space and time and even somewhat in polarity summer and fall are the most active seasons for undercurrent eddy generation while there is less seasonal variation at surface most of the eddies have radii in the range of 25 100 km sea level anomaly amplitudes of 1 4 cm and vorticity normalized by f amplitudes of 0 025 0 2 many of the eddies formed near the coast travel considerable distance westward with speeds about 2 km day consistent with the effect anticyclones and cyclones show equatorward and poleward displacements respectively long lived surface eddies show a cyclonic dominance the subsurface california undercurrent generates more long lived anticyclones than cyclones through instabilities and topographic coastline effects in contrast surface eddies and subsurface cyclones have much more widely distributed birth sites the majority of the identified eddies have lifetimes less than a season eddies extend to 800 1500 m depth and have distinctive vertical structures for cyclones and anticyclones eddies show high nonlinearity rotation speed higher than propagation speed and hence can be efficient in transporting materials offshore

mesoscale eddies in the northwestern pacific ocean three dimensional eddy structures and heat salt transports the region encompassing the kuroshio extension ke in the northwestern pacific ocean 25 n 45 n and 130 e 180 e is one of the most eddy energetic regions of the global ocean the three dimensional structures and transports of mesoscale eddies in this region are comprehensively investigated by combined use of satellite data and argo profiles with the allocation of argo profiles inside detected eddies the spatial variations of structures of eddy temperature and salinity anomalies are analyzed the results show that eddies predominantly have subsurface near surface intensified temperature and salinity anomalies south north of the ke jet which is related to different background stratifications between these regions a new method based on eddy trajectories and the inferred three dimensional eddy structures is proposed to estimate heat and salt transports by eddy movements in a lagrangian framework spatial distributions of eddy transports are presented over the vicinity of the ke for the first time the magnitude of eddy induced meridional heat freshwater volume transport is on the order of 0 01 pw 103 m3 s the eddy heat transport divergence results in an oceanic heat loss south and heat gain north of the ke thereby reinforcing and counteracting the oceanic heat loss from air sea fluxes south and north of the ke jet respectively it also suggests a poleward heat transport across the ke jet due to eddy propagation

air sea heat fluxes associated to mesoscale eddies in the southwestern atlantic ocean and their dependence on different regional conditions heat fluxes between the ocean and the atmosphere largely represent the link between the two media a possible mechanism of interaction is generated by mesoscale ocean eddies in this work we evaluate if eddies in southwestern atlantic swa ocean may significantly affect flows between the ocean and the atmosphere atmospherics conditions associated with eddies were examined using data of sea surface temperature sst sensible shf and latent heat flux lhf from ncep cfsr reanalysis on average we found that ncep cfsr reanalysis adequately reflects the variability expected from eddies in the swa considering the classical eddy pumping theory anticyclonic cyclonic eddies cause maximum positive negative anomalies with maximum mean anomalies of 0 5 c 0 5 c in sst 6 w m2 4 w m2 in shf and 12 w m2 9 w m2 in lhf however a regional dependence of heat fluxes associated to mesoscale cyclonic eddies was found in the turbulent brazil malvinas confluence bmc region they are related with positive heat flux anomaly ocean heat loss while in the rest of the swa they behave as expected ocean heat gain we argue that eddy pumping do not cool enough the center of the cyclonic eddies in the bmc region simply because most of them trapped very warm waters when they originate in the subtropics the article therefore concludes that in the swa 1 a robust link exists between the sst anomalies generated by eddies and the local anomalous heat flow between the ocean and the atmosphere 2 in the bmc region cyclonic eddies are related with positive heat anomalies contrary to what is expected

eddy activity in the four major upwelling systems from satellite altimetry 1992 2007 eddy activity in the four major eastern boundary upwelling systems ebus is investigated using 15 years of satellite altimetry data based on the analysis of more than 4000 long lived eddy trajectories in every ebus we show that mesoscale structures are mainly generated along the continental coasts and south of the main archipelagos and propagate westward with velocities increasing toward the equator these mesoscale eddies having radii of 70 160 km are then frequently observed along the coastal transition zones and frontal regions and some large oceanic areas are preferentially populated by cyclonic or anticyclonic eddies temporal variations of the number of newly formed eddies and the associated eddy activity index defined as the mean eddy energy density are finally examined at seasonal and interannual scales the strongest seasonal interannual respectively variations are observed in the california benguela upwelling systems the proposed indices also exhibit contrasted long term trends in each ebus which suggests that eddy activity might be sensitive to a warming climate

main eddy vertical structures observed in the four major eastern boundary upwelling systems in the four major eastern boundary upwelling systems ebus mesoscale eddies are known to modulate the biological productivity and transport near coastal seawater properties toward the offshore ocean however little is known about their main characteristics and vertical structure this study combines 10 years of satellite altimetry data and argo float profiles of temperature and salinity and our main goals are i to describe the main surface characteristics of long lived eddies formed in each ebus and their evolution and ii to depict the main vertical structure of the eddy types that coexist in these regions a clustering analysis of the argo profiles surfacing within the long lived eddies of each ebus allows us to determine the proportion of surface and subsurface intensified eddies in each region and to describe their vertical structure in terms of temperature salinity and dynamic height anomalies in the peru chile upwelling system 55 of the sampled anticyclonic eddies aes have subsurface intensified maximum temperature and salinity anomalies below the seasonal pycnocline whereas 88 of the cyclonic eddies ces are surface intensified in the california upwelling system only 30 of the aes are subsurface intensified and all of the ces show maximum anomalies above the pycnocline in the canary upwelling system 40 of the aes and 60 of the ces are subsurface intensified with maximum anomalies extending down to 800 m depth finally the benguela upwelling system tends to generate 40 50 of weak surface intensified eddies and 50 60 of much stronger subsurface intensified eddies with a clear geographical distribution the mechanisms involved in the observed eddy vertical shapes are discussed

cross spectral analysis of the sst 10 m wind speed coupling resolved by satellite products and climate model simulations this study aims to determine the spatial temporal scales where the sst forcing of the near surface winds takes places and its relationship with the action of coherent ocean eddies here cross spectral statistics are used to examine the relationship between satellite based sst and 10 m wind speed w fields at scales between 10 2 10 4 km and 10 1 10 3 days it is shown that the transition from negative sst w correlations at large scales to positive at oceanic mesoscales occurs at wavelengths coinciding with the atmospheric first baroclinic rossby radius of deformation and that the dispersion of positively correlated signals resembles tropical instability waves near the equator and rossby waves in the extratropics transfer functions are used to estimate the sst driven w response in physical space w c a signal that explains 5 40 of the mesoscale w variance in the equatorial cold tongues and 2 15 at extratropical sst fronts the signature of ocean eddies is clearly visible in w c accounting for 20 60 of its variability in eddy rich regions to provide further insight on the role of ocean eddies in the sst driven coupling the analysis is repeated for two climate model ccsm simulations using ocean grid resolutions of 1 circ eddy parameterized lr and 0 1 circ eddy resolving hr the lack of resolved eddies in lr leads to a significantly underestimated mesoscale w variance relative to hr conversely the w c variability in hr can exceed the satellite estimates by a factor of two at extratropical sst fronts and underestimate it by a factor of almost six near the equator reflecting shortcomings of the ccsm to be addressed in its future developments

structure and surface properties of eddies in the southeast pacific ocean 1 a number of studies have posited that coastally generated eddies could cool the southeast pacific ocean sep by advecting cool upwelled waters offshore we examine this mechanism by characterizing the upper ocean properties of mesoscale eddies in the sep with a variety of observations and by estimating the surface layer eddy heat flux divergence with satellite data cyclonic and anticyclonic eddies observed during two cruises featured deep positive salinity anomalies along the 26 5 kg m 3isopycnal indicating that the eddies had likely trapped and transported coastal waters offshore the cyclonic eddies observed during the cruises were characterized by shoaling isopycnals in the upper 200 m and cool near surface temperature anomalies whereas the upper ocean structure of anticyclonic eddies was more variable using a variety of large scale observations including argo float profiles drifter records and satellite sea surface temperature fields we show that relative to mean conditions cyclonic eddies are associated with cooler surface temperatures and that anticyclonic eddies are associated with warmer surface temperatures within each data set the mean eddy surface temperature anomalies are small and of approximately equal magnitude but opposite sign eddy statistics drawn from satellite altimetry data reveal that cyclonic and anticyclonic eddies occur with similar frequency and have similar average radii in the sep a satellite based estimate of the surface layer eddy heat flux divergence while large in coastal regions is small when averaged over the sep suggesting that eddies do not substantially contribute to cooling the surface layer of the sep

processes controlling upper ocean heat content in drake passage 1 a 16 year record of expendable bathythermograph transects across drake passage is used to examine variability in upper ocean heat content that is not associated with the annual cycle links between upper ocean heat content and anomalous heat fluxes winds two large scale climate indices and mesoscale eddies and meanders are examined results suggest that interannual variations in surface heat fluxes explain 5 to 10 of the variance in upper ocean heat content anomalous surface heat fluxes are linked to meridional wind anomalies upstream of drake passage which in turn are linked to forcing by el nino southern oscillation enso and the southern annular mode sam enso and sam are correlated with upper ocean heat content at near zero lags and statistically significant correlations occur at longer time lags as well the impact of mesoscale eddies and meanders on upper ocean heat content is explored with the use of a tracked eddy database an empirical relationship is constructed relating upper ocean heat content anomalies to eddy length scales and amplitudes eddies and meanders are estimated to account for more than one third of the nonannual cycle variance in drake passage upper ocean heat content

petrographic classification of oil shales abstract oil shales are a diverse group of rocks that contain mineral matter and organic matter the organic matter is derived from terrestrial lacustrine and marine organisms the maceral nomeclature system of the international committee for coal petrology used widely in coal petrography and petroleum source rock studies is suitable for describing the organic matter in oil shales provided the terminology for organic matter derived from algal precursors is divided into two submacerals telalginite and lamalginite macerals of the liptinite group including alginite are volumetrically important constituents of oil shales and are the major source of the shale oil that is formed during pyrolysis liptinite is easily characterized and quantified using fluorescence mode microscopy and thus the type and abundance of liptinite can be used as a basis for a petrographic classification of oil shales oil shales are grouped using the environmental of deposition as the discriminatory criterion into the three primary divisions of terrestrial lacustrine and marine oil shales type and abundance of liptinite is then used to subdivide these three groups into cannel coal torbanite lamosite further subdivided into rundle type lamosite and green river type lamosite marinite tasmanite and kuckersite

characteristic trace fossil associations in oxygen poor sedimentary environments the sedimentologic record of oxygen poor depositional environments typically includes trace fossils produced by deposit feeding organisms we propose an oxygen controlled trace fossil model in which increasing oxygen concentration of interstitial water in sediment parallels a transition from fodinichnia dominated through pascichnia dominated to domichnia dominated trace fossil associations in certain places such as parts of the late paleozoic oquirrh basin in utah this model provides a reasonable alternative to the more traditional depth controlled model of trace fossil distribution

oil generation capacity of coals as a function of coal age and aliphatic structure abstract the relative proportions of aliphatic ch2 ch3 aliphatic hydrogen hali together with the aliphatic chain length in a series of carboniferous permian jurassic and cenozoic humic coals have been analysed using ftir and ruthenium tetroxide catalysed oxidation rtco followed by gc ms analysis of the n monocarboxylic acids esterified to assess their ability to generate oil most of the coals contain 2 11 vol liptinite only coals with almost similar hydrogen indices his were compared as they were considered to possess comparable hydrocarbon generation potentials all contain isolated aromatic hydrogen haro in the coal structure and a considerable proportion of aliphatic chains in the range c16 18 hi values cannot alone explain the proportion of aliphatic ch2 implying that for coals haro contributes to the measured hi cenozoic coals contain the highest proportion of aliphatic ch2 and hali and the content of longer chain aliphatics c18 increases considerably from palaeozoic to cenozoic coals aliphatic chains c18 are absent from or very restricted in the carboniferous coals and most of the permian coals indicate no or a negligible ability to generate oil jurassic coals show a slightly better potential whereas cenozoic coals contain aliphatic chains up to at least c35 demonstrating the greatest capacity to generate oil in addition to significant gas potential multivariate data analysis suggests that the aliphatic chains c24 are related to the collodetrinite liptodetrinite matrix which is a prominent constituent of cenozoic coals with regard to oil potential the coals from the major coal forming periods may be ranked carboniferous permian

short term upwelling events at the western african coast related to synoptic atmospheric structures as derived from satellite observations satellite scatterometers provide continuously valuable surface wind speed and direction estimates over the global ocean on a regular grid both in space and time the level 3 data derived from the advanced scatterometer ascat available at 1 4 spatial resolution hereafter as25 and quick scatterometer quikscat available on 1 2 and 1 4 horizontal grids qs50 and qs25 respectively are studied at regional scales in both the benguela and canary upwelling systems they are compared to the european center for medium range weather forecast surface wind analysis with insight into their intrinsic and actual spatial resolutions in the coastal band the finest spatial patterns are found in the qs25 winds and are o 75 km this demonstrates the sensitivity of the high resolution satellite derived winds to coastal processes related to sea surface temperature sst perturbations and land sea transition next short lived upwelling episodes sues calculated from sst anomalies are defined consistently with the qs25 actual resolution these cold events refer to local short lived perturbations that add to seasonal upwelling variability we characterize concomitant atmospheric synoptic conditions for sues identified at chosen latitudes and highlight two subregions in both upwelling systems with contrasted patterns for the alongshore wind stress component and curl the complexity of the latter patterns is closely linked to local short term sst variability closer to the shore numerical sensitivity experiments show that the imbalance between ekman transport and ekman pumping has an impact on ocean dynamics wind reduction in the coastal qs25 forcing partially induced by orography tends to reduce coastal sst cooling

electron spin resonance esr dating abstract esr dating has been systematically applied in earth sciences and archaeology since 1975 when ikeya dated a stalactite from the akiyoshi cave in japan in the meantime this new technique has been successfully applied to the dating of materials such as speleothems spring deposited travertines mollusc shells corals and tooth enamel the present research focuses on the dating of quartz which allows the age assessment of heated ceramics volcanic rocks intrafault material or windblown sediments esr dating is based on the measurement of the number of paramagnetic centers in a mineral these centers are generated by alpha beta and gamma radiation of the matural radioelements such as u th and k and have accumulated over time two parameters have to be determined the accumulated dose ad and the dose rate d to which the sample was exposed this review comprises three major parts a introduction into esr dating b application of the method and c appendices giving detailed description of dose rate calculation physical basis of electron spin resonance the esr spectrometer and esr lines the major emphasis lies on the outline of the application of esr dating this includes the discussion of the esr signals of the various materials sampling sample preparation and measurement techniques

kerogen origin evolution and structure kerogen commonly defined as the insoluble macromolecular organic matter om dispersed in sedimentary rocks is by far the most abundant form of om on earth this fossil material is of prime importance as the source of oil and natural gas moreover kerogen can provide essential information on major topics such as past environments climates and biota this review reports the main advances in kerogen studies since the comprehensive synthesis edited by durand durand b ed kerogen insoluble organic matter from sedimentary rocks editions technip paris 1980 it is organized into eight sections the first two are concerned with the successive definitions of kerogen and the definition used here the different techniques used for kerogen isolation without loss or degradation and basic kerogen analysis the third and fourth focus on sedimentary om sources and preservation processes in relation to depositional environment including sedimentation conditions favourable for kerogen accumulation and extrapolation to past geological time great strides have been made in the latter topics over the last 25 years owing to a combination of classical studies in organic geochemistry and studies in other domains such as biogeochemistry oceanography hydrology and soil science along with the development of powerful analytical tools the next two sections deal with the different kerogen classifications by type and kerogen evolution and maturation upon burial in sediments structural modelling of coal and kerogen based on physical and or chemical structural analysis is described in the following section although only statistical the models thus derived provide a synthetic view of the main structural resemblances and differences among various samples in relation to source maturity or physicochemical properties finally the last section explores some of the advances in kerogen understanding expected for the near future the review includes a list containing about 500 references

overestimate of stalagmitic calcite esr dates due to laboratory heating in the use of esr for dating stalagmitic calcite from palaeolith1c caves it has recently been reported that to obtain reliable ages the samples should be heated before measurement for example for 24 h at 170 190 c specifically this procedure has been used by yokoyama et al 1 for samples from the lowest stalagmitic floor in caune de l arago the site of the tautavel man in southern france and an age of 700 kyr obtained however the results presented here indicate that straight line extrapolation involved in finding the age is not valid if this heating procedure is used and that its use leads to a substantial overestimate of the age by nearly a factor of two in the application mentioned

esr dating of corals and pre annealing effects on esr signals abstract corals commonly exhibit electron spin resonance esr signals of a g 2 0057 b g 2 0031 and c g 2 0007 pre annealing using a modern coral sample at 120 180 c has significantly changed gamma ray sensitivities of the esr signals the sensitivities of all the three signals at first increased and then decreased with the pre annealing these results suggest that the amount of sources of the signals changes with geologic time this effect can cause underestimation of esr ages for holocene and latest pleistocene corals and can cause overestimation for early and middle pleistocene corals using signal c possible models associated with a monomer and a trimer of cation impurities for signals c and a respectively are discussed based on third order trap decay kinetics

chemotaxonomy for naturally macerated tree fern cuticles medullosales and marattiales carboniferous sydney and mabou sub basins nova scotia canada abstract naturally macerated cuticles nmc and one synangium representing medullosalean and marattialean tree fern species from two carboniferous coalfields in nova scotia canada are investigated the samples were analyzed by infrared spectroscopy ftir and by pyrolysis gas chromatograph mass spectrometry py gc ms techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of carboniferous fern species assuming genetically dependent make up of cuticles ftir derived ch 2 ch 3 ratios in conjunction with contributions from carboxyl groups demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py gc ms however the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group changes in the chemical make up of naturally macerated cuticles due to sample preparation are discussed

signature of mesoscale eddies in satellite sea surface salinity data a persistent signature of coherent mesoscale eddies in sea surface salinity sss is revealed by analyzing the relationship between satellite sss and sea surface height ssh variability in an eddy following reference frame our analysis focuses on mid ocean eddies in two representative regions the southern indian ocean and the north atlantic subtropical gyre the resulting composite averages reveal a clear signature of mesoscale eddies in satellite sss with typical sss anomalies of 0 03 0 05 psu the spatial structure of eddy induced sss perturbations can be characterized as a superposition of a dipole structure arising from horizontal advection of the background sss gradient by eddy velocity field and a monopole structure related to the eddy core the observed relationships between sss and ssh anomalies are used to provide a regional assessment of the role of mesoscale eddies in the ocean freshwater transport in the north atlantic subtropical gyre this article is protected by copyright all rights reserved

rings in the ocean certain robust long lived eddy features in t he world s ocean have come to be k nown as rings the nomenclature stems from fuglister 1 1972 who c oined t he name based on the c ircle or ring of gulf stream waters t hat surrounded a class of eddies formed from t he g ulf stream through the pinch off of meanders here it s uffices to define rings as intense eddies or vortices that represent a wrapped up piece of a major ocean c urrent they t ranslate over space scales of hundreds to thousands of k ilometers and exist for periods lasting from months to years rings move t hrough the ocean carrying anomalies s imilar to the contrasts in physical biological and chemical properties observed across the major ocean c urrents while the term ring is t ied to fuglister t he existence ofthese features was evident at least as early as t he 1930s when iselin 2 1936 1940 encountered strong cold anomalies in the region south of the gulf stream that we would identify as c old corc cyclonic rings today iselin fully rec ognized these features as part of the highly time dependent eddy motion in the ocean later iselin fuglister 1948 were the first to survey what is now k nown as a warm core anticyc lonic ring there are tw o types of rings cold core rings are made up of w aters from the poleward s ide of c urrents like the gulf stream that are introduced to

the westphalian d fossil lepidodendrid forest at table head sydney basin nova scotia sedimentology paleoecology and floral response to changing edaphic conditions copyright c 1996 elsevier science b v all rights reserved strata of westphalian d age on the western coast of the sydney basin expose a fossil forest of approximately 30 lepidodendrid trees within one of several clastic splits of the harbour seam a mutidisciplinary approach was employed to interpret the origins of the coal bed the depositional history of the site and the response of the fossil forest to changing edaphic conditions the megaspore and miospore records indicate that the mire vegetation was dominated by arboreous lycopsids especially paralycopodites with subdominant tree ferns petrographic palynological and geochemical evidence suggest that the harbour coal bed at table head originated as a rheotrophic cf planarr mire eutric histosolr the mire forest is interpreted to have been engulfed by prograding distributary channel sediments sparse protist assemblages are suggestive of a freshwater delta plain lake environment occasionally in contact with brackish waters lepidodendrids persisted as site colonizers of clastic substrates even after burial of the rheotrophic peatland and influenced the morphology of deposited sediment but apparently were unable to colonize distributary channels equivocal taxonomic data compression fossilsr show the fossil forest to have been composed of both monocarpic lepidodendronr and polycarpic diaphorodendron paralycopodites sigillariar lycopsids genera recorded in the palynology of the uppermost ply of the underlying coal bed comparatively rare within the clastic beds of the fossil forest however is the stem compression of paralycopodites whose dispersed megapores and miospores dominate the underlying coal bed tree diameter data recorded equivalent to breast height indicate a forest of mixed age these data would appear to suggest that some lepidodendrids employing a polycarpic reproductive strategy were better able to cross the ecological barrier imposed between peat and clastic substrates foliar compressions indicate that an understory or stand of psaronius type tree ferns co existed with the lepidodendrids on clastic substrates which developed as incipient gleysol soils the entombment of the forest can be ascribed to its distributary coastal setting local subsidence and a seasonal climate that fostered wildfire and increased sedimentation

temporal and spatial distribution of ostracodes across the pennsylvanian permian boundary interval in eastern north america abstract ostracodes recovered from eastern north american coal measures in the appalachian illinois and maritimes basins have the potential to resolve the temporal and spatial relationships of the strata deposited during the pennsylvanian permian boundary interval the ostracode associations include 1 a pennsylvanian virgilian gzhelian marine association dominated hollinella cushmani with abundant brachiopods and foraminifera exclusive to the gil 30 core in kentucky illinois basin 2 a latest pennsylvanian virgilian gzhelian brackish association dominated by geisina upsoni kellet cavellina nebrascensis geintz and velatomorpha fittsi kellet exclusive to the gil 30 core in kentucky illinois basin and 3 an uppermost permian asselian sakmarian association of nonmarine taxa dominated by whipplella cuneiformis holland whipplella parvula holland paleodarwinula hollandi scott and haworthina bulleta harris and lalicker that occurs in the uppermost continental facies of both the illinois and dunkard basins a comparable nonmarine association of paleodarwinula hollandi and whipplella bretonensis copeland occurs in the bolsovian to cantabrian moscovian to kasimovian coal measures of the maritimes basin of atlantic canada the data presented herein provides new information about the withdrawal of marine waters from several major late paleozoic basins in eastern north america mid continental marine influence persisted into the latest pennsylvanian to earliest permian during deposition in the eastern illinois basin on the western appalachian coastal plain the uppermost nonmarine association of nonmarine ostracoda in both the illinois basin and dunkard basin indicates a synchronous development of aquatic freshwater faunas during lower permian times with increasing geographic isolation of the eastern north american basins the dispersal and radiation of ostracoda in these basins was apparently facilitated by brood rearing as demonstrated by the dominance of the platycopina and darwinulocopina

compression cuticle relationship of seed ferns insights from liquid solid states ftir late palaeozoic early mesozoic canada spain argentina abstract cuticles have been macerated from suitably preserved compressed fossil foliage by schulze s process for the past 150 years whereas the physical biochemical relationship between the coalified layer with preserved cuticle as a unit has hardly been investigated although they provide complementary information this relationship is conceptualized by an analogue model of the anatomy of an extant leaf vitrinite mesophyll cuticle biomacropolymer compression alkaline solutions from schulze s process as a proxy for the vitrinite are studied by means of liquid solid states fourier transform infrared spectroscopy ftir in addition cuticle free coalified layers and fossilized cuticles of seed ferns mainly from canada spain and argentina of late pennsylvanian late triassic age are included in the study sample infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll biomacropolymer characteristics the compression records two pathways of organic matter transformation one is the vitrinized component that reflects the diagenetic post diagenetic coalification history parallel with the evolution of the associated coal seam the other is the cuticle that reflects the sum total of evolutionary pathway of the biomacropolymer its monomeric or polymeric fragmentation though factors promoting preservation include entombing clay minerals and lower ph conditions caution is advised when interpreting liquid state based ftir data as some ir signals may have resulted from the interaction of schulze s process with the cuticular biochemistry a biochemical study course for taphonomy is suggested as fossilized cuticles cuticle free coalified layers and compressions are responses to shared physicogeochemical factors

the recognition of the base of the westphalian d stage in britain the i u g s subcommission on carboniferous stratigraphy recommends the base of the westphalian d be recognized using plant macrofossils in britain however south wales is the only coalfield where the distribution of the plants is sufficiently well known for them to be used to locate this boundary elsewhere in britain other criteria have been used particularly non marine bivalves and plant microfossils but these must be used with considerable caution modified journal abstract

fluvial channel and overbank deposits from the westphalian of the durham coalfield ne england the westphalian upper carboniferous coal measures of the durham coalfield in ne england were deposited in lower and upper delta plain environments distributary channels crossed the plain and were separated by shallow interdistributary lakes and bays detailed observation of three dimensional 3 d opencast surface mine exposures in collaboration with subsurface borehole analysis has revealed the existence of five varieties of channel deposits and two associated overbank facies within the durham coal measures major distributary channels were the major avenues of sediment transport across the coal measures plain were variably sinuous mostly 1 2 km wide and deposited elongate belts of sand mostly up to 5 km wide proximal major crevasse splay channels formed by the breaching of major channel banks during flood events were straight sand filled and up to 400 m wide minor distributary channels formed by the sustained operation of such crevasses varied from straight to highly sinuous and deposited shoestring sand mud belts up to a few hundred metres wide minor crevasse channels generally straight and up to 50 m wide were formed through bank breaching of minor and in a few cases major distributaries distal feeder channels formed down palaeocurrent extensions of minor distributaries which supplied interdistributary minor delta subsystems were generally straight and up to 200 m wide of the two types of channel overbank levee deposits recognized one comprising thinly interbedded fine grained sandstone and siltstone claystone is mostly though not exclusively associated with major distributary channels the other consisting of massive siltstones with regularly spaced thin claystone bands is uniquely developed at the margins of minor distributary channels the lower part of the westphalian a succession in the northern pennines records a change in the depositional environment upwards from a lower to upper delta plain through this transition major channel deposits show evidence of having evolved from being of dominantly low sinuosity to being more variable in morphology channel sedimentation was profoundly influenced by regular possibly seasonal variations in flow stage and sediment load

mesoscale eddies off peru in altimeter records identification algorithms and eddy spatio temporal patterns relatively little is known about coherent vortices in the eastern south pacific along the peruvian coast even with regard to basic facts about their frequency of occurrence longevity and structure this study addresses these issues with nearly 15 years of relatively high resolution satellite altimetry measurements we first compare two distinct automated methods for eddy identification the objective validation protocol shows that the rarely used geometrical or winding angle method based on the curvature of the streamline functions is more accurate than the commonly used okubo weiss algorithm which defines a vortex as a simple connected region with values of okubo weiss parameter weaker than a given threshold we then investigate vortices off peru using more than 20 000 mesoscale eddies identified by the winding angle method coherent eddies characterized by a high ratio of vorticity to deformation rate are typically formed along the coast and propagate westward at 3 6 cm s 1 the vortices have a mean radius of 80 km increasing northward and are most frequently observed off of chimbote 9s and south of san juan 15s the mean eddy lifetime is about 1 month but if eddies survive at least 2 months the probability for surviving an additional week or month is constant at 90 or 67 anticyclonic eddies tend to propagate northwestward whereas cyclonic vortices migrate southwestward in general cyclones and anticyclones are similar except for eddies surviving at least 6 months in this case after a similar 3 4 months of radius and amplitude growth amplitudes or sizes decay particularly rapidly for anticyclonic or cyclonic eddies in terms of intensity cyclonic eddies show a rapid decay during the first 3 months before arriving at a quasi constant value whereas anticyclones exhibit steady decline finally eddy temporal variations were examined at seasonal and interannual scales in the coastal region favorable to the formation of energetic mesoscale structures on seasonal scales eddy activity is maximal in fall and minimum in spring at interannual scales the eddy activity index was maximal during the strong el nino of 1997 1998 but another strong maximum of eddy activity also occurred late in 2004 these temporal variations are probably associated with the intensification of the upwelling thermal front and with the passage of coastal trapped waves which generate baroclinic instabilities further investigation of the mechanisms involved on the eddy genesis is needed

chemometric study of functional groups in pennsylvanian gymnosperm plant organs sydney coalfield canada implications for chemotaxonomy and assessment of kerogen formation abstract the samples comprise the foliage of four pteridosperm medullosalean plant fossil species of differing preservation states and one of a cordaitean species from two canadian maritime sub basins of carboniferous age 300 ma sydney and stellarton coalfields nova scotia respectively included in the sample set were some coal samples from sydney coalfield along with published data for coal macerals for comparison by applying schulze s maceration process to the fossil foliage to obtain the cuticles five sample forms evolved viz compressions cuticles and fossilized cuticles and acidic and alkaline solutions from schulze s process to which was added the sydney coal samples as the sixth form area integration of the absorbance spectra from solid and liquid state fourier transform infrared ftir spectroscopy produced functional chemical parameters which were organized into a data matrix of eight variables and 62 samples 8 62 matrix since we were interested in grouping the sample forms as a function of phytochemistry functional groups to assess primarily the palaeophytotaxonomic potential as a general approach to carboniferous taxonomy principal components were extracted from the matrix and a subset of 4 33 samples in order to refine the grouping results from the initial component analysis in each case a two component model resulted accounting for least 80 of the cumulative variance overall the results are encouraging in offering increasing support for fossil leaf chemotaxonomy but bearing in mind the limited sampling number 56 and restricted sampling of genera 5 apart from this general conclusion which supports our previous ftir work vis a vis chemotaxonomy we noted functional group similarities in our ftir data with types of kerogen and coal macerals on this basis we hypothesize that in combination with the different preservation states of our fossil specimens these factors have a bearing on kerogen genesis from plant material i e the oil and gas prone types i and ii

phyto and chronostratigraphical correlations between the late pennsylvanian morien group sydney nova scotia and the silesian pennant measures south wales three macrofloral interval zones lobatopteris vestita l micromiltoni and linopteris bunburii recognized in the westphalian d and the cantabrica biozone in the stephanian of europe are also present in the morien group pictou group of sydney coalfield nova scotia these zones allow a more refined correlation to be made between sequences of the same age in the sydney and south wales coalfields and thus between western europe and north america in general

complex trichomes associated with foliar odontopteris schlotheimii brongniart manebach type locality germany implication for taxonomy abstract reported for the first time is a physical association of complex structured trichomes with foliar odontopteris schlotheimii brongniart 1831 from the type manebach formation germany this is based on examining rock matrices dissolved by hydrofluoric acid of bipinnate and pinnate material these trichomes and their inferred dense distribution most significantly are directly comparable with those of specimens of odontopteris cantabrica wagner 1969 from the canadian sydney coalfield used as index fossil to establish the cantabrian substage this result is one strong argument that invites comparison with o schlotheimii in addition to the acknowledged common pinnule morphologies of o cantabrica and o schlotheimii additionally trichomes are not observed in samples of the rock matrix of a fragmentary axis associated with lesquereux specimen of o schlotheimii southern anthracite field eastern pennsylvania usa results of the trichomic comparison and taxonomic implication thereof will be discussed in a future paper

functional groups in a single pteridosperm species variability and circumscription pennsylvanian nova scotia canada abstract multiple foliar specimens of the late pennsylvanian fossil pteridosperm gymnosperm alethopteris zeilleri ragot wagner were collected from one restricted stratigraphical horizon in the canadian sydney coalfield variability of functional group distribution using ftir technique was studied in compressions adaxial versus abaxial cuticles and in unseparated cuticles as a function of maceration time from 48 to 168 h the results obtained document spectral variability that could be expected within specimens of one species for example ch 2 ch 3 and al ox ratios can differ by as much as 20 of the values moreover the experiments performed confirm that by using a previously established maceration protocol long maceration periods do not bias ftir spectra in terms of oxygenation overprinting the inference that this cuticle is robust under the given diagenetic level probably reflects a reassuring degree of chemical fidelity of the pennsylvanian plant to support carboniferous chemotaxonomic observations

application of reflectance micro fourier transform infrared analysis to the study of coal macerals an example from the late jurassic to early cretaceous coals of the mist mountain formation british columbia canada abstract the applicability of the reflectance micro fourier transform infra red spectroscopy ftir technique for analyzing the distribution of functional groups in coal macerals is discussed high quality of spectra comparable to those obtained using other ftir techniques kbr pellet and transmission micro ftir indicate this technique can be applied to characterizing functional groups under most conditions the ease of sample preparation the potential to analyze large intact samples and ability to characterize organic matter in areas as small as 20 m are the main advantages of reflectance micro ftir the quantitative aspects of reflectance micro ftir require further study the exaples from the coal seams of the mist mountain formation british columbia show that at high volatile bituminous rank reflectance micro ftir provides valuable information on the character of aliphatic chains of vitrinite and liptinite macerals because the character of aliphatic chains influences bond disassociation energies such information is useful from a hydrocarbon generation viewpoint in medium volatile bituminous coal liptinite macerals are usually not detectable but this technique can be used to study the degree of oxidation and reactivity of vitrinite and semifusinite

subregional characterization of mesoscale eddies across the brazil malvinas confluence horizontal and vertical motions associated with coherent mesoscale structures including eddies and meanders are responsible for significant global transports of many properties including heat and mass mesoscale vertical fluxes also influence upper ocean biological productivity by mediating the supply of nutrients into the euphotic layer with potential impacts on the global carbon cycle the brazil malvinas confluence bmc is a western boundary current region in the south atlantic with intense mesoscale activity this region has an active role in the genesis and transformation of water masses and thus is a critical component of the atlantic meridional overturning circulation the collision between the malvinas and brazil currents over the patagonian shelf slope creates an energetic front that translates offshore to form a vigorous eddy field recent improvements in gridded altimetric sea level anomaly fields allow us to track bmc mesoscale eddies with high spatial and temporal resolutions using an automated eddy tracker we characterize the eddies across fourteen 5 5 subregions eddy centric composites of tracers and geostrophic currents diagnosed from a global reanalysis of surface and in situ data reveal substantial subregional heterogeneity the in situ data are also used to compute the evolving quasi geostrophic vertical velocity qg associated with each instantaneous eddy instance the qg eddy composites have the expected dipole patterns of alternating upwelling downwelling however the magnitude and sign of azimuthally averaged vertical velocity varies among subregions maximum eddy values are found near fronts and sharp topographic gradients in comparison with regional eddy composites subregional composites provide refined information about mesoscale eddy heterogeneity this article is protected by copyright all rights reserved

reliability of thermoluminescence dating of stalagmitic calcite the dating of stalagmitic calcite at the early hominid site of caune de l arago france by the esr technique of yokoyama et al 1 has yielded ages for the underlying floor of 7 105 yr these are in serious disagreement with the chronology obtained by thermoluminescence tl 2 which indicates a date of around 3 105 yr the discrepancy has been attributed3 to instability of the tl 280 c dating signal for which a mean life of 2 105 yr was proposed here the arguments on which this claim is based are criticized and evidence is presented that corrections to tl age measurements incurred by signal fading are even for the oldest stalagmites from the site probably 15 the conflict between the tl and esr chronologies at caune de l arago is explicable in terms of the esr results reported by skinner4

the westphalian stephanian macrofloral record from the south wales coalfield uk the south wales coalfield has the most complete westphalian macrofloral record anywhere on the variscan foreland or adjacent basins with 135 biodiversity meaningful morphospecies having been recognized all of the standard macrofloral biozones of the westphalian stage have been recognized although a detailed comparison with the central pennines coalfields has indicated some discrepancies in the relative positions of the biozonal boundaries total species richness progressively increases through the langsettian substage and then remains relatively stable through most of the duckmantian and bolsovian substages there is a distinct reduction in total species richness towards the top of the bolsovian substage but this partially recovers in the middle asturian substage with the appearance of a range of marattialean ferns and medullosalean and callistophytaleans pteridosperms there is no evidence of any significant drop in total species richness towards the top of the succession indicating that conditions at this time were relatively stable the change from coastal floodplain to alluvial braidplain conditions in middle bolsovian times correlates with a marked increase in the proportion of medullosalean remains being preserved in the adpression record reflecting an expansion of the clastic substrate habitats

coupling of extratropical mesoscale eddies in the ocean to westerly winds in the atmospheric boundary layer abstract the sea surface temperature sst signature in mesoscale eddies in the western boundary current extensions around the globe and in the antarctic circumpolar current are found to alter the surface stress associated with background westerly winds producing wind stress curl wsc residuals of eddy scale that are capable of modifying the eddy dynamics this is revealed by examining satellite derived mesoscale sea level height slh sst and neutrally stable zonal surface wind zsw residuals together for 18 months in the presence of background westerly winds on basin scales warm mesoscale eddies reduce the stability of the marine atmospheric boundary layer increasing the zonal air sea momentum flux measured by satellite scatterometry warm sst residuals of 0 8 c are capable of producing westerly zsw residuals of 1 2 m s 1 under background westerly winds of 6 m s 1 alternatively this means increasing the otherwise neutrally stable drag coefficient by 40 consistent with in situ measurement