monoterpenylabietenoids novel biomarkers from extant and fossil taxodioideae and sedimentary rocks abstract the presence of 7 p cymenylferruginol and its diagenetic biomarkers occurring in cenozoic fossil plants and mesozoic siltstones and coals has been studied using gas chromatography mass spectrometry both 7 and 7 p cymenylferruginol isomers were the dominant natural products with two novel minor additional isomers namely 3 and 3 p cymenylferruginol and two hydrocarbons 7 and 7 p cymenyldehydroabietane the other tentatively assigned aromatic hydrocarbons were 9 10 p cymenylretene and 9 p cymenylsimonellite which were present in upper cretaceous and lower jurassic sedimentary rocks with their further dehydrogenation products diterpenoid dimers were also tentatively identified in trace amounts with 11 and 14 ferruginylferruginol as the dominant compounds our results show that the p cymenylferruginols and p cymenyldehydroabietanes are not thermally stable and that their occurrence in sedimentary rocks is controlled by the maturity of the organic matter om also chamaecydin identified for the first time in pre paleogene strata was not detectable when the om maturity based on vitrinite reflectance was higher than 0 45 0 5 rr

high temporal resolution so2 flux measurements at erebus volcano antarctica abstract the measurement of so2 flux from volcanoes is of major importance for monitoring and hazard assessment purposes and for evaluation of the environmental impact of volcanic emissions we propose here a novel technique for accurate and high time resolution estimations of the gas flux we use two wide field of view uv spectrometers capable of collecting instantaneously light from thin parallel cross sections of the whole gas plume obviating the need for either traversing scanning or imaging it enables tracking of inhomogeneities in the gas cloud from which accurate evaluation of the plume velocity can be made by correlation analysis the method has been successfully applied on mt erebus volcano antarctica it yields estimations of the plume velocity and gas flux at unprecedented time resolution 1 hz and high accuracy uncertainty of 33 during a 2 h experiment on 26 december 2006 so2 flux varied between 0 17 and 0 89 0 2 kg s 1 with a vertical plume velocity varying between 1 and 2 5 0 1 m s 1 these measurements provide insight into the short term variations of the passive degassing of this volcano renowned for its active lava lake a cyclicity in flux ranging from about 11 24 min is evident we propose two physical mechanisms to explain this degassing pattern associated to periodic supply of either gas rich magma or gas alone into the lake the dual wide field of view doas technique promises better integration of geochemical and geophysical observations and new insights into gas and magma dynamics as well as processes of magma storage and gas segregation at active volcanoes

volcanic eruption velocities measured with a micro radar a novel technique to quantitatively assess volcanic eruption dynamics is presented we report on measurements of volcanic eruption velocities with a modified micro radar doppler anemometer on stromboli volcano italy the mean vertical eruption velocity recorded during a four day period in late 1996 was around 10 m s which is somewhat on the small side for strombolian eruptions however the activity of stromboli volcano during this period was very weak explaining the relatively small velocities the technique used is much better in resolution than older techniques based on static photos and allows a continuous monitoring of the volcanic activity in addition to the velocity information recorded by the doppler spectrum it also contains information on the density of the ejected material and the size distribution of the particles in the volcanic jet

open and almost shut case for explosive eruptions vent processes determined by so2 emission rates at karymsky volcano kamchatka vent processes were examined at karymsky volcano kamchatka by measuring so2 emissions using a correlation spectrometer cospec continuous high sensitivity cospec measurements and physical observations were collected on 11 and 12 september 1999 when karymsky was producing small ashy eruptions every 5 20 min each eruptive event began with an explosion and audible rumbling lasting 30 s followed in some cases by audible chugging lasting to 2 min gas plumes accompanied each event and almost without exception the plumes dissipated and became invisible despite significant so2 emissions variations in so2 output show distinctive patterns that correlate with eruption activity maximum so2 output occurred following each explosion and then declined rapidly to low but detectable levels in contrast a second type of event often associated with audible chugging was characterized by high so2 output long after the initial ash blast variations in degassing at karymsky can be explained by secondary boiling gas pressure accumulation and vent resealing we developed a new application of the cospec technique to study the dynamic vent processes of erupting volcanoes this application provides insights into the processes that occur at the otherwise inaccessible vents of erupting volcanoes particularly when a volcano changes from passive degassing and small explosions to degassing patterns that may precede a larger and more dangerous eruption

waves of bubbles in basaltic magmas and lavas initially homogeneous suspensions of bubbles in basaltic magmas and lava flows may become unstable and form rising waves or layers of bubbles we derive a set of model equations for the two phase bubble liquid system and present the results of a linear stability analysis and numerical simulations periodic vesicle layers are preserved in columbia liver flows with a spacing of 1 m the prediction of the stability analysis combined with a simple model for solidification of the lava suggests that vesicle layers may represent waves of bubbles formed within the flow the spacing of layers is determined by a balance between the growth of bubbles and hydrodynamic self diffusion vesicular layers preserved in columbia liver flows may thus form by hydrodynamic processes and do not require the repeated injection of fresh volatile rich magma or a periodic nucleation of bubbles waves of bubbles may also develop in magma chambers and conduits and could play a role in eruption dynamics

organism substrate interactions and astrobiology potential models and methods abstract organism substrate interactions and their products biogenic structures are important biosignatures on earth this study discusses the application of ichnology the study of organism substrate interactions to the search for present and past life beyond earth three main questions are addressed 1 why to look for biogenic structures i e traces and ichnofabrics beyond earth 2 what biogenic structures to expect on other planets moons and asteroids 3 how to study extraterrestrial biogenic structures review of terrestrial evidence highlights a set of properties that make traces and ichnofabrics important for the search of potential extraterrestrial life trace fossils preserve the activity of soft bodied organisms biogenic structures are resilient to processes that obliterate other biosignatures i e mechanical and chemical degradation diagenesis tectonism and metamorphism traces are very visible biosignatures traces indicate environment and behaviour traces can be universal biosignatures i e biosignatures ideally suited for detecting any type of life a model of organism substrate interactions beyond earth is here proposed expected extraterrestrial traces are those that manifest behaviours that allow to maintain homeostasis excavations meandering traces and biodeposition structures most of the existing rovers and orbiters provide basic instruments for searching these traces it is here suggested that the search for extraterrestrial biogenic structures by rovers would also benefit from artificial adjustable lighting gpr lidar and drilling equipment with optical televiewer in this study open access databases of rover and orbiter imagery have been searched for traces and ichnofabrics but no unquestionable evidence of biogenic structures beyond earth has been found besides those produced by humans this sounds along the lines of the famous fermi paradox if the universe is teeming with aliens where are their traces results of this search show that habitable environments are not the only place to look for biogenic structures non habitable environments such as moons without atmosphere can favour the preservation of shallow tier traces the better preservation potential of traces compared to other biosignatures greatly widens the issue of planetary protection including the interaction between astronauts or vehicles and the substrate may produce disturbances although this study highlights a new direction of study with the tools and concepts of ichnology dialogue between the astrobiological and ichnological communities is needed to use its full potential and possibly answer one of the major questions of science does life exist beyond earth

what can thermal infrared remote sensing of terrestrial volcanoes tell us about processes past and present on mars over the past fifty years a diverse set of thermal infrared tir remote sensing data has been acquired from the orbits of earth and mars which both have ubiquitous volcanic landforms these data vary in spatial spectral and temporal resolution and are critical for investigating an ever expanding set of science applications including the focus of this review paper volcanic processes volcanic studies using tir data include active monitoring of flows and plumes on earth and mapping the compositional and thermophysical diversity on mars furthermore recent advances in high resolution low cost ground and laboratory tir instrumentation now help to augment the orbital data through a synergistic approach to data analysis and validation field and laboratory studies also serve as terrestrially focused analogues that provide important insights to interpret the geologic processes that have operated on other planetary surfaces including mars this review expands upon our invited talk of the same title at the 2014 geological society of america meeting to include several case studies designed to give the reader an overview of how tir data can be applied to volcanic processes on earth and mars these case studies highlight prior work by the authors presented at past meetings but which have not been published elsewhere the examples were chosen specifically to identify the tir data similarities between the two planets and include analyses of volcanic surfaces to 1 derive composition and texture using tir spectra earth and mars 2 analyze mantled flows with thermophysical data earth and mars 3 estimate lava discharge rate using tir derived temperature earth with application to mars and 4 model flow dynamics based on geomorphic measurements mars because of our focus on the tir we do not attempt to document other remote sensing wavelength regions nor even every volcanic study using tir data as tir instruments have improved over time along similar trajectories the higher spatial and spectral resolutions provide the ability to examine volcanic processes in more quantitative ways despite the fact that no tir instrument has ever been designed solely to study volcanic phenomena whether these trends continue for both planets will depend on the design of new tir technologies the data they produce and the science that results from the data

infrasonic waves and volcanic tremor at stromboli the origin of the volcanic tremor is still under debate many theories have been proposed in the last years but none has yet been completely accepted in 1993 highly sensitive pressure sensors 2 175 pa volt used to monitor the explosive activity at stromboli have revealed unexpected correlation between small spike shaped pressure signals 1 2 pa and volcanic tremor these pressure pulses repeat regularly in time with a recurrent period of ca 1 s video camera images allowed us to correlate the pressure pulses with small gas bursts occurring at one of the active vents the striking correlation 0 971 between infrasonic and seismic energy fluctuations is particularly meaningful in the frequency domain infrasonic and seismic signal share the same spectral content 3 hz for every station within a range of 700 m around the craters correlations in time and frequency domain remained unaltered during the 1994 field experiments moreover during 1994 the increased degassing activity has been followed by an increase in pressure release 7 8 pa and by a shift towards higher frequencies 8 hz both in the infrasonic and seismic records infrasonic waves and volcanic tremor show similar energy fluctuations and frequency contents appearing therefore to be produced by the same dynamical process on this basis we claim that volcanic tremor at stromboli originates by continuous outbursting of small gas bubbles in the upper part of the magmatic column

ground temperature change observed at unzen volcano associated with the 1990 1995 eruption abstract ground temperature associated with eruptive activity of unzen volcano southwestern japan was observed in a cave about 680 m west of the central vent based on the data during 1991 1996 eliminating the effects of seasonal change the temperature rose to the highest level probably around the first half of 1992 hereafter the temperature decreased gradually year by year at least up to the autumn of 1996 beyond the level recovered at the beginning of the lava extrusion in may 1991 although it is not necessarily conclusive the present observation suggests a possible rise in ground temperature prior to the commencement of the first phreatic eruption in november 1990 if so a careful observation may help to predict future eruptions by detecting a precursory rise of the ground temperature in this volcano

4d velocity of strombolian eruptions and man made explosions derived from multiple doppler radar instruments abstract we used a novel system of three continuous wave doppler radars to successfully record the directivity of i strombolian explosions from the active lava lake of erebus volcano antarctica ii eruptions at stromboli volcano italy and iii a man made explosion in a quarry erebus volcano contains a convecting phonolite lava lake presumably connected to a magma chamber at depth it is one of the few open vent volcanoes that allow a direct observation of source processes during explosions its lava lake is the source of frequent violent strombolian explosions caused by large gas bubbles bursting at the lake surface the exact mechanism of these bubble bursts is unclear as is the mechanism of the creation of the infrasound signal accompanying the explosions we use the doppler radar data to calculate the directivity of strombolian eruptions at erebus this allows us to derive information about the expected type of infrasound source pattern i e the role of a dipole in addition to the monopole signature and the physical structure of the volcano we recorded 10 large explosions simultaneously with three radars enabling us to calculate time series of 3d directivity vectors i e effectively 4d which describe the direction of preferred expansion of the gas bubble during an explosion such directivity information allows a comparison to dipole infrasound radiation patterns recorded during similar explosions only a few weeks later video observations of explosions support our interpretation of the measurements we conclude that at erebus the directivity of explosions is mainly controlled by random processes since the geometry of the uppermost conduit is assumed to have a large effect on the directivity of explosions the results suggest a largely symmetrical uppermost conduit with a vertical axis of symmetry for infrasound recordings a significant dipole signature can be expected in addition to the predominant monopole signature

the molecular composition of cretaceous ambers identification and chemosystematic relevance of 1 6 dimethyl 5 alkyltetralins and related bisnorlabdane biomarkers abstract one of the major components of the organic solvent extractable fraction of cretaceous ambers is 1 6 dimethyl 5 isopentyltetralin a compound that has been incorrectly or not identified in previous reports on the molecular composition of cretaceous ambers here the purification and structural identification of 1 6 dimethyl 5 isopentyltetralin is reported from amber samples of the cretaceous penacerrada ii deposit at penacerrada alava basque cantabrian basin spain the structural identification of 1 6 dimethyl 5 isopentyltetralin allowed the complete identification of related compounds comprising the family of 1 6 dimethyl 5 alkyltetralins this suggests that those compounds with concentrations up to 27 of the total organic extract of amber from penacerrada are characteristic for labdane type biomarkers in cretaceous fossil resins and their distributions indicate different compositional families related to their botanical and topographic origin also the name amberene is proposed for the main molecule of this group the relative proportion of the amberene type compounds suggests three compositional families for the cretaceous spanish ambers

thermal seismic and infrasound observations of persistent explosive activity and conduit dynamics at santiaguito lava dome guatemala abstract in january 2003 we deployed a seismo acoustic array along with thermal sensors to define the dynamics and source characteristics of persistent intermittent explosive activity at the santiaguito lava dome guatemala seismic and acoustic waveforms accompanying thermal transients i e the thermal signature produced by the vertical ash plumes allowed discrimination of 35 explosions from minor degassing events during the 15 5 h observation period characteristics of thermal transients along with elastic and thermal energy flux from the explosive ash emissions allowed for a standardized measurement of eruption intensity duration frequency and repose interval using the thermal data we calculated a range of minimum exit velocities of 16 76 m s and convective rise rates of 9 26 m s to heights of 100 and 600 m above the vent source depths for the explosions were calculated using the thermo acoustic delay indicating a source 100 620 m below the vent the intensity of the explosions based on thermal amplitude and proxies for elastic energy released is not dependent on repose interval or depth the data support the notion for shear induced fragmentation at the conduit walls due to stick slip movement of the upper degassed part of the magma column as a source mechanism loci of explosion depths suggest that this operates within a 500 m thick dacite plug in the uppermost portion of the conduit

eruption dynamics of the sw crater of stromboli volcano italy an interdisciplinary approach abstract we report on the evaluation of in situ measurements of eruption velocities and relative mass flux collected by doppler radar as well as acoustic and infrared data that were recorded at stromboli volcano doppler radar observations were made alongside thermal acoustic and seismic measurements to 1 further investigate the complex waveforms of the sw crater by combining infrasonic infrared and doppler radar measurements 2 establish a relationship between infrared acoustic and doppler radar measurements and 3 verify that all instruments observe the same behavior in terms of relative mass eruption rate we also explore the relationship between kinetic and acoustic energy released during an eruption comparing the different methods to each other we are able to show that the mass erupted can be estimated either from the total reflected doppler radar energy or from infrared observations however neither thermal nor reflected energy can provide a value in terms of absolute mass in kg the erupted masses of different eruptions can only be evaluated relative to each other using the combined three data sets we especially focus on the eruption dynamics of the sw crater of stromboli namely its fluctuations in eruption strength these pulses in one eruptive event so called pulsations dominate more than 40 of the eruptions of sw crater previous models that explain pulsations to be generated by multiple consecutively exploding bubbles are supported by our combined analysis of infrasound thermal data particle velocities and the reflected energy

paleoenvironmental and paleobiogeographic implications of a new ediacaran body fossil from the neoproterozoic carolina terrane stanly county north carolina new partial swartpuntiid from neoproterozoic age rocks of stanly county north carolina herein assigned to cf swartpuntia sp along with previously described pteridinium carolinaensis aspidella other metazoan trace fossils and previously reported radiometeric ages suggest nama assemblage type affinities for the carolina terrane the new specimen cf swartpuntia sp and associated radiometric ages add further information pertaining to proposed geographic linkages between the carolina terrane and the avalon terrane this new swartpuntiid may be evolutionarily convergent in terms of habitat preference to the infaunal or partially infaunal habitat preferred by other members of the nama type ediacaran biota such as pteridinium and rangea

coupled thermal oscillations in explosive activity at different craters of stromboli volcano 1 thermal infrared thermometers deployed 250 m from stromboli s active craters can detect thermal emissions during strombolian explosions explosions appear as spikes in thermal time series with variations in the mass erupted during each event revealed by pulses in the time series during may 2001 stromboli s ne and sw craters showed consistently different thermal signatures sw crater events were characterized by long lasting 10 s higher amplitude thermal signals with significant fluctuations whereas the ne crater was characterized by short 5 s impulsive lower amplitude signatures the two craters showed well correlated variations in thermal amplitude evolving over periods of several hours and providing strong evidence for linkage of the craters to a common feeding system affected by cyclic processes that drive steady variations in the style of emission

explosive volcanic eruptions ix the transition between hawaiian style lava fountaining and strombolian explosive activity the commonest eruption styles of basaltic volcanoes involve hawaiian lava fountaining or intermittent strombolian explosions we investigate the ways in which magma rise speed at depth magma volatile content and magma viscosity control which of these eruption styles takes place we develop a model of the degree of coalescence between gas bubbles in the magma which allows us to simulate the transition between the two extreme styles of activity we find that magma rise speed is the most important factor causing the transition with gas content and viscosity also influencing the rise speed at which the transition occurs counter to intuitive expectations a decrease in gas content does not cause a transition from hawaiian to strombolian activity but instead causes a transition to passive effusion of vesicular lava rather a change from hawaiian to strombolian style requires a significant reduction in magma rise speed

gas bubble dynamics model for shallow volcanic tremor at stromboli volcanic tremor at stromboli aeolian islands italy is correlated to small infrasonic transients ripepe et al 1996 which repeat almost rhythmically in time in a range between 0 8 and 1 2 s we demonstrate that infrasonic transients are associated to small gas bubble 0 5 m burstings which produces no transients in the seismic signal tremor ground displacement attenuates with the inverse of the distance from the craters indicating that the source is shallow short term energy release shows that infrasonic and seismic signals are linked to the same dynamical process while at the long term scale it is evident that the two signals are controlled by two distinctive mechanisms we suggest that the possible physical model acts in two steps first gas coalescence and then gas bursting in our model the seismic signal is related to the coalescence of a gas bubble from a layer of small bubbles while the infrasonic signal is linked to the bursting of the bubble when it reaches the magma surface gas bubbles could form by free coalescence in magma or could be forced to coalesce by a structural barrier we calculate that forced coalescence induces in magma a pressure change 104 pa 2 orders of magnitude higher than free coalescence and it explains best the tremor ground displacement 10 5 m recorded at stromboli moreover forced coalescence evidences the role of a structural barrier such as a dike in volcanic tremor source dynamics in this gas dynamic process the delay time of 1 2 s between infrasonic pulses could reflect the gas nucleation interval of basaltic magma thomas et al 1993 manga 1996 we propose that the source function for the shallow volcanic tremor at stromboli could be the viscoelastic reaction of the magma to the pressure decrease induced by gas bubble growth rate under constant depressurization the spectrum of our source function is controlled by the time duration of the pressure pulse which represents the viscoelastic relaxation time of the magma and gas bubble growth rate the predicted asymptotic decay of the frequency contents fits the spectral behavior of the volcanic tremor ground displacement recorded at stromboli we show that the same spectral behavior can be found in ground displacement spectra of volcanic tremor recorded on different volcanoes

biomarkers of holocene buried conifer logs from bella coola and north vancouver british columbia canada abstract the biomarker compositions of a holocene seep oil liquefied resin originating from a buried log of douglas fir pseudotsuga menziesii from bella coola bc canada and a holocene pine wood pinus sp sample from north vancouver bc canada were analyzed using gas chromatography mass spectrometry gc ms the total extract of the bella coola sample contains the sesquiterpenoid derivative calamenene and diterpenoids of the labdane abietane pimarane and phyllocladane classes a novel series of successively degraded labdane derivatives labdan 15 oic acid norlabdanoic acids drimenoic acid was detected in the polar fraction and a diagenetic pathway is proposed aromatic abietanes are the major components in the neutral fraction the neutral fraction of the pine wood contains two sesquiterpenoids calamenene cadalene diterpenoids of the abietane pimarane isopimarane and kaurane classes and a series of steroids 18 norabieta 8 11 13 triene dehydroabietin is the major component among the predominantly aromatic abietanes based on the compositions of the terpenoids it is concluded that the diagenesis of the pine and douglas fir logs probably occurred under anaerobic conditions leading to reductive reactions such as decarboxylation of resin acids with concurrent oxidation reactions to form the aromatic derivatives

onset of the persistent activity at stromboli volcano italy stromboli known worldwide as the lighthouse of the mediterranean is commonly believed to have been in a state of persistent activity for the past 2000 2500 years however historical sources older than 1000 a d are not accurate enough to assess if the activity of the volcano was exactly the same as we see at present in order to attempt to identify the onset of the present eruptive regime and assess if it has been maintained with the same characteristics through time stratigraphic and radiometric studies of the recent tephra deposits were undertaken up to 4 m deep stratigraphic trenches dug at a height of approximately 500 m on the ne flank of the volcano exposed a conformable tephra pile containing charcoal fragments one of the most interesting finds was the discovery of a 7 cm thick weathered bed rich in organic matter thin palaeosol approximately 3 m below the surface the sequence underneath the palaeosol consists of decimetre thick lapilli fallout beds alternating with ash deposits bearing small charcoals with calibrated ages of between the fourth century b c and the first century a d the sequence above the palaeosol is charcoal free and consists of coarse ash deposits with discrete centimetre thick lapilli fallout beds composed of crystal poor golden pumice and subordinate crystal rich black scoriae similar to scoria pumice pairs emitted during the more energetic explosions of the present day activity the data collected indicate that between the third and seventh centuries a d after a period of quiescence the activity resumed with an eruptive style identical to the present one we conclude that the lighthouse of the mediterranean actually began its activity in a period much later than previously thought

magma budgets and steady state activity of vulcano and stromboli we present three models for magma budget during steady state volcanic activity by which non erupted magma is emplaced as dykes or cumulates or crystallises in place using gas and thermal data we apply our models at vulcano to calculate degassing cooling and crystallisation of magma at a rate of 40 375 kg s 1 within a magma body with an upper surface at a 2 km depth at stromboli we calculate a steady magma supply of 300 1300 kg s 1 to shallow 1 km depths

real time measurement of volcanic so 2 emissions validation of a new uv correlation spectrometer flyspec a miniaturized lightweight and low cost uv correlation spectrometer the flyspec has been devel oped as an alternative for the cospec which has long been the mainstay for monitoring volcanic sulfur dioxide fluxes field experiments have been conducted with the flyspec at diverse volcanic systems including masaya nicaragua po as costa rica stromboli etna and vulcano italy villarica chile and kilauea usa we present here those validation measurements that were made simultaneously with cospec at kilauea between march 2002 and february 2003 these experiments with source emission rates that ranged from 95 to 1 560 t d 1 showed statistically identical results from both instruments so2 path concentrations ranged from 0 to 1 000 ppm m with average correlation coefficients greater than r 2 0 946 the small size and low cost create the opportunity for flyspec to be used in novel deployment modes that have the potential to revolutionize the manner in which volcanic and industrial monitoring is performed

blue fluorescing amber from cenozoic lignite eastern sikhote alin far east russia preliminary results abstract blue and greenish yellow in addition to ordinary yellow orange amber has recently been found in a lignite seam in the zerkal nenskaya depression primorsky krai russia the amber is associated with abundant charcoal and fusain fragments in the host rocks its ftir spectra indicate the presence of significant quantities of volatile matter including free hydroxyl groups and carbon dioxide both co 2 and oh contents are greater in the greenish yellow and blue hard varieties suggesting rapid heating possibly from a wildfire followed by rapid cooling in water as a causative agent of amber hardening and extreme polymerization this process and the following amber deposition in the reduced environment might produce the fluorescent aromatics that have been previously suggested and confirmed by this study as the blue glow main cause

trace fossil preservation and the early evolution of animals abstract the trace fossil record is an important element in discussions of the timing of appearance of bilaterian animals a conservative approach does not extend this record beyond about 560 555 ma crucial to the utility of trace fossils in detecting early benthic activity is the preservational potential of traces made close to the sediment water interface our studies on the earliest cambrian sediments suggest that shallow tiers were preserved to a greater extent than typical for most of the phanerozoic this can be attributed both directly and indirectly to the low levels of sediment mixing the low levels of sediment mixing meant that thin event beds were preserved the shallow depth of sediment mixing also meant that muddy sediments were firm close to the sediment water interface increasing the likelihood of recording shallow tier trace fossils in muddy sediments preservation of surficial trace fossils in this type of setting remains problematic but the above factors suggest that also these can be expected to have left a reasonable record overall the trace fossil record can be expected to provide a sound record of the onset of bilaterian benthic activity the lack of convincing trace fossils significantly before the cambrian supports models of late appearance of macroscopic benthic bilaterians

visible and invisible volcanic plumes 1 volcanic plumes discharging from craters or fumaroles are usually observed at active volcanoes these plumes are divided into two categories from their appearance one is a transparent invisible plume composed of volcanic gases and the other is a white visible plume containing water droplets in addition to the vapors the difference in plume visibility is caused by changes in the conditions that control water condensation in the plume we present a simple model describing the condition for the water condensation in the plume as a function of the exit temperature volcanic gas composition atmospheric temperature and humidity and tested the model with a field observation the result indicates that we can estimate the exit temperature from the visibility of the plume under known atmospheric conditions

terpenoids in extracts of lower cretaceous ambers from the basque cantabrian basin el soplao cantabria spain paleochemotaxonomic aspects the composition of terpenoids from well preserved cretaceous fossil resins and plant tissues from the amber bearing deposits of el soplao and reocin in cantabria northern spain have been analyzed using gas chromatography mass spectrometry and the results are discussed using the terpenoid composition of extant conifers as a reference amber is present at many horizons within two units of coastal to shallow marine siliciclastics of albian and cenomanian age the fossil resins are associated with black amber jet and abundant well preserved plant cuticle compressions especially those of the extinct conifer genus frenelopsis cheirolepidiaceae we report the molecular characterization of two types of amber with different botanical origins one of them is characterized by the significant presence of phenolic terpenoids ferruginol totarol and hinokiol and pimaric isopimaric acids as well as their diagenetic products the presence of phenolic diterpenoids together with the lack of abietic and dehydroabietic acids excludes both pinaceae and araucariaceae as sources for this type of amber the biological diterpenoid composition is similar to that observed for extant cupressaceae the second type of amber is characterized by the absence of phenolic terpenoids and other specific biomarkers some terpenoids with uncertain structure were detected as well as the azulene derivative guaiazulene our results suggest that the amber from cantabria could be fossilized resin from frenelopsis and other undetermined botanical sources the biological terpenoid assemblage confirms a chemosystematic relationship between frenelopsis and modern cupressaceae

multiparametric study of the february april 2013 paroxysmal phase of mt etna new south east crater european fp7 med suv mediterranean supersite volcanoes grant number 308665 european research council european fp7 fp 2007 2013 erc grant number 279802 sigma sistema integrato di sensori in ambiente cloud per la gestione multirischio avanzata

mixing of stratified liquids by the motion of gas bubbles application to magma mixing mafic magma underlying more silicic magma in a reservoir can exsolve volatiles as it crystallizes forming bubbles that segregate upwards to the interface with the overlying silicic magma we describe laboratory experiments designed to investigate how gas bubbles migrate into the more viscous upper layer in one regime bubbles move individually across the interface entraining a small quantity of lower layer fluid and the two layers become progressively stirred into a homogeneous mixture in a second regime bubbles form a thin foam layer at the interface which becomes gravitationally unstable giving rise to two phase plumes which rise and produce a coarse mixture of the liquids for a given viscosity ratio the transition between these regimes occurs when the gas flux is greater than a critical value which we found to decrease with increasing viscosity ratio we estimate the critical gas flux for magmatic conditions and how vesiculation may vary with pressure degree of crystallization and the composition of volatile components mafic inclusions which are often found in silicic to intermediate lavas can form in the plume regime analysis of the instability of the foam predicts wavelengths of between 1 cm and 1 m which is consistent with the observed sizes of inclusions volatiles from the mafic magma may be efficiently transported by this mechanism into the viscous silicic magma as bubble plumes despite low stokes velocities for individual vesicles at small viscosity ratios or low gas fluxes the bubbling regime can produce hybrid magmas

thermal observations of gas pistoning at kilauea volcano 1 data acquired by three continuously recording thermal infrared thermometers situated on the north rim of pu u o o crater at kilauea volcano during 2002 revealed episodes of periodic thermal pulses originating from a degassing vent on the crater floor these thermal pulses are interpreted as gas release jetting events associated with gas pistoning a mechanism observed previously at both mauna ulu and pu u o o during a 35 day long period spanning june and july 2002 gas pistoning was frequently the dominant mode of gas release with as many as several hundred pulses occurring in uninterrupted series on other days degassing alternated between periods of quasi continuous gas jetting and intervals of gas pistoning that contained a few to a few dozen pulses characteristic time intervals between pistoning events ranged from 2 up to 7 min we identify three types of pistoning type 1 involves emission of lava followed by gas jetting and drain back type 2 is the same but the elevated position of the vent does not allow postjet drain back and type 3 involves gas jetting only with no precursory lava flow to explain gas pistoning we apply a model whereby a stagnant cap of degassed magma develops in the conduit below the vent gas bubbles rise through the magma column and collect under the cap the collective buoyancy of these bubbles pushes the cap upward when the cap reaches the surface it erupts from the vent as a lava flow unloading of the conduit magma in this way results in an abrupt pressure drop i e the overburden felt by the bubbles is reduced causing explosive gas expansion in the form of gas jetting from the vent this terminates the event and lava drains back into the conduit to start the cycle anew in the case where there is no surface lava emission or drain back the cap instead pushes into and spreads out within a subsurface cavity again this unloads the conduit magma and terminates in explosive gas release once gas is expelled lava in the cavity is free to drain back we hypothesize that pistoning is a stable mode of degassing for low viscosity basaltic magmas with appropriate conduit geometries and volatile supply rates

an unprecedented condensation pathway leading to the formation of phenolic c40 bis diterpenoids in sediments from the lower oligocene of the rhine rift valley abstract in the course of a detailed palaeoenvironmental study based on biomarker distributions in sediments of rupelian age lower oligocene from the rhine rift valley an outcrop sample rich in higher plant fossil remains was collected from a quarry near the city of burnhaupt le haut south alsace france in agreement with the macrofossil assemblage most of the biomarkers were related to terrigenous organic matter as evidenced by the presence of di and triterpenoid derivatives from vascular plants the aromatic hydrocarbon fraction was also shown to contain two predominant series of unknown c 40 oxygenated compounds as indicated by high resolution mass spectrometry isolation of the predominant compound from the first series and of two isomers from the second was undertaken to determine the structures from nuclear magnetic resonance nmr studies thus we determined that both series of compounds consist of bis diterpenoids made up of phenolic sub units related to totarol and sempervirol possibly originating from podocarpaceae their formation comprises a first step involving oxidative coupling between the two phenolic monomeric sub units via a free radical mechanism and leading to the formation of an ether bond first series of compounds or a carbon carbon bond second series of compounds in the case of the compounds from the second series a second acid catalysed cyclisation step likely results in the formation of a central dibenzofuranyl moiety it remains unclear however whether these condensation cyclization mechanisms are biologically mediated or result from diagenetic reactions

dynamics of the 5 april 2003 explosive paroxysm observed at stromboli by a near vent thermal seismic and infrasonic array 1 on 5 april 2003 an array of thermal infrasonic and seismic sensors tracked the dynamics of a major explosive paroxysmal event at stromboli the thermal signal recorded a decline 1 hour before the paroxysm which itself lasted 6 5 minutes and opened with a 14 s low thermal amplitude phase this was followed by three main explosive phases with gas and ejecta velocities of 324 and 185 m s being calculated for the first phase the delay time between thermal and infrasonic signals indicates a very shallow 150 m source for fragmentation a strong tilt component in the seismic signals shows that the conduit began to expand at least 90 s before the explosion large seismic amplitudes were recorded during the emission onset the seismic signal can thus be related to stress build up followed by release during the ejection of the gas particles mixture we calculate that the cloud of hot gas and ash emitted during the explosion had an overpressure of 3 8 mpa and involved 5 7 105 m3 2 9 106 kg of gas

investigation of at vent dynamics and dilution using thermal infrared radiometers at masaya volcano nicaragua abstract in order to develop a detailed understanding of the dynamics of gas puffing gas release as a series of distinct pulses and more sustained degassing steady plumes of gas during persistent volcanic degassing measurements of gas mass flux are required in the vicinity of the volcanic vent masaya volcano nicaragua a persistently degassing system is an ideal location for measuring the dynamics of releases of volcanic gas in the first few seconds of their propagation we carried out two field experiments during february 2002 and march 2003 during which thermal infrared thermometers were targeted into the degassing vent at masaya to record thermal variations related to variations in the at vent gas emission over short on the order of seconds time scales the thermometers recorded an oscillating signal as gas puffs passed through the field of view detailing variations in the degassing process developing over time scales of seconds these data were processed to extract puff frequencies amplitudes durations emission velocities and volumes these data showed that over time periods of hours the total gas flux was stable with little variation in the puffing frequency however between the 2002 and 2003 data set we noted an increase in mean plume temperature puffing frequency puff emission velocity and puff volume as well as a decrease in mean puff duration these changes were consistent with a thermal data derived increase in emitted gas flux from 4 2 10 7 m 3 d 1 to 6 4 10 7 m 3 d 1 between the two campaigns turbulent gas puffs entrain surrounding air and quantifying the magnitude of air entrainment or dilution represents a major challenge for the measurement of total volcanic gas emissions our observations of small gas puffs suggest that they behave as turbulent buoyant thermals and we use equations for mass momentum and buoyancy coupled with the standard entrainment assumption for turbulent buoyant flows to estimate the gas puff dilution the theoretically calculated dilution of 0 09 and 0 24 between emission and detection yields total so 2 mass fluxes of 209 t d 1 and 864 t d 1 for 2002 and 2003 respectively this compares well with uv spectrometer so 2 fluxes of 470 and 680 t d 1 for february 2002 and march 2003 respectively

molecular tracers preserved in lower jurassic blanowice brown coals from southern poland at the onset of coalification organic geochemical and petrological characteristics abstract the petrographic and molecular characteristics of the pliensbachian toarcian blanowice brown coals and associated sediments are described these coals are generally dominated by vitrain macerals although in one sample the inertinite is 60 this is interpreted as a result of wildfire or peat fire activity which was confirmed by the co occurrence of charcoal fragments and elevated relative concentrations of unsubstituted pahs in the samples vitrinite reflectance values are in the range of 0 49 0 56 ro and the c content varies from 30 3 61 9 placing the coals within the sub bituminous coal group however detailed characterization of coal extracts revealed their highly immature character based on the occurrence of phenolic abietanes such as ferruginol sugiol and 7 oxototarol as well as other biomolecules including labdanoic acid cholesterol and sitosterol this is one of the first descriptions of natural product compounds in jurassic sedimentary rocks moreover in addition to typical lignin decomposition products dicarboxylic acids with a preponderance of succinic acid were identified to the best of our knowledge free dicarboxylic acids have not been reported previously from coal extracts these acids are characteristic resin constituents we speculate that a low ca 40 50 c but long term temperature influence led to an increased vitrinite reflectance values ca 0 55 ro with only minor changes to the composition of unstable biomarkers and biomolecules moreover the resin matrix could protect unstable compounds against geochemical structural alteration vitrinite reflectance values may also be elevated due to oxidation which caused paler in colour reaction rims the presence of phenolic abietanes and the absence of abietic and dehydroabietic acids suggest that the cupressaceae and or podocarpaceae families were the most likely peat forming plant species

thermal seismic and infrasonic evidences of variable degassing rates at stromboli volcano abstract during june 1999 we measured the amplitude and rate number of events per second at which gas exited the vent at stromboli volcano as discrete gas bursts or puffs this allowed us to identify two styles of gas burst puffing activity the first is characterized by frequent rapidly rising puffs the second by less frequent slowly rising puffs each style persisted over 5 40 min long durations and was associated with a high and low number of strombolian explosions per hour respectively each period was also associated with characteristic delay times between the arrival of the infrasonic and thermal signals during strombolian explosions the delays were longer during vigorous puffing periods to explain our observations we propose a model in which the degassing process cycles between vigorous and weak degassing phases during vigorous degassing phases bubble layers ascend the conduit at a frequency of 0 5 1 0 s 1 this high degassing level reflects a gas rich magma column and leads to an increased rate in the formation of shallow foams and hence an increase in puffing and explosive activity as well as a higher free surface level and or gas jet velocity during weak phases bubble layers ascend the conduit at a reduced frequency of 0 2 0 3 s 1 during such times the magma column is poor in gas this leads to a decreased rate of foam layer formation and hence a reduction in puffing and explosive activity as well as a lower free surface level and or gas jet velocity variations in puffing activity can thus be used to track changes in the rate at which the shallow system is supplied by fresh gas rich magma our observations indicate that the two degassing styles last from 5 to 40 min and that the switch from one to the other occurs over a matter of minutes

a case history of paroxysmal explosion at stromboli timing and dynamics of the april 5 2003 event abstract on april 5 2003 stromboli volcano italy produced the most violent explosion of the past 50 years the event was exceptionally well documented thanks to the presence on the island of several scientists and a large number of instruments deployed over the preceding months to monitor the effusive eruption that began in december 2002 integration of visual documentation deposit features and geophysical data allowed an accurate reconstruction of the explosive event and its dynamics the eruption consisted of a 8 min long explosive event which evolved through four phases whose timing was precisely recorded by an infrared thermometer located about 450 m from the summit crater phases 2 and 3 lasted 39 and 42 s respectively both had an impulsive character were responsible for ejecting almost the entire mass of the pyroclastic products phases 1 and 4 represented respectively a short lived precursory event and a waning tale during phase 2 meter sized ballistic blocks were launched with velocities of 170 m s to altitudes of up to 1400 m above the craters these fell on the volcano flanks and on the village of ginostra about 2 km distant from the vent a vertical jet rose above the craters which developed to feed a convective plume that reached a height of up to 4 km the calculated mass of the phase 2 fallout deposit and mass discharge rate were 1 1 1 4 108 kg and 2 8 3 6 106 kg s respectively during phase 3 a scoria flow deposit with an estimated volume of 0 9 1 1 104 m3 was erupted from the same vent that fed the ongoing sustained lava flow the average mass discharge rate for this phase was 2 5 3 1 105 kg s products emitted during phases 2 and 3 consisted of lithic and fresh magmatic material in similar proportions the juvenile fraction consisted of a deep originated almost aphyric highly vesicular pumice mingled with a shallow derived crystal rich moderately vesicular scoria similarities with the eruption dynamics of other historical paroxysms at stromboli makes the april 5 2003 explosion representative of these highly energetic events that constitute the most hazardous volcanic phenomena at stromboli volcano

the further adventures of tin man vertical temperature gradients at the lotts creek coal mine fire perry county kentucky abstract the lotts creek coal mine fire developed in an abandoned underground and surface mine in the hindman hazard no 9 coalbed in the hazard north 7 minute quadrangle in a study conducted in april and may 2012 an array of five thermocouples with 1 m vertical separation between individual thermocouples was suspended in an active vent of the fire data were collected from each thermocouple for 21 days at 1 min intervals for many days small thermal gradients were noted on 3 may 2012 the 10th day of the investigation a relatively extreme thermal event occurred with a nearly 95 c difference in the 2 m between the 2nd and 4th thermocouples other extreme heating events were noted but none as intense as the latter event such events were overprinted on the diurnal and shorter breathing cycles of the fire and the complications induced by changing atmospheric conditions and the shifting of the fire front as the coal burned the 3 may thermal event may have been a result of a sudden opening of a vent with the consequent influx of air increasing the intensity of the fire since the experiment was run remotely without visits to the site between the time of placement and pick up of the data logger assembly no one witnessed the incident

effects of thermal maturity on biomarker distributions in gondwana coals from the satpura and damodar valley basins india abstract organic geochemistry of gondwana coals especially the distribution of molecular fossils or biomarkers is not well constrained throughout the world in this study we have therefore evaluated biomarker signatures along with bulk organic matter and petrographic characteristics in coal samples collected from two gondwana basins in india satpura basin kanhan coalfield and damodar valley basin jharia coalfield from both coalfields the samples were collected from the lower permian barakar formation which is one of the major coal bearing strata in india a significant variation in thermal maturity levels in the samples is indicated by rock eval pyrolysis and petrographic analysis with the kanhan samples generally belonging to immature to early mature stage while the jharia samples display characteristics of overmature coals this variation in the thermal maturity strongly affects the biomarker distributions especially the terpenoids hopanes and steranes were considerably degraded due to thermal maturation and were below detection limit in the overmature samples presence of aliphatic diterpanes ent 16 h kaurane 16 h phyllocladane as well as aromatic diterpanes retene methylretenes tetrahydroretene simonellite and bisnorsimonellite in low maturity samples indicate terrestrial input possibly from the primitive conifers however the aliphatic and aromatic diterpanes were below detection limit in overmature samples making it difficult to infer their source distributions of polycyclic aromatic hydrocarbons pahs are also controlled by thermal maturity levels as evident from difference in pah ratios in the low and high maturity samples

precambrian fossil vermiforma is a tectograph vermiforma antiqua cloud 1976 1 once celebrated as the earliest animal fossil of the united states is actually a tectonic artifact the main argument is that the congruence and equal orientation of multiple patterns on the same bedding plane are incompatible with swaying worm bodies or worm burrows as shown by analog and numerical simulations these structures can be explained as tracks of particles that broke out from the base of an overlying turbidite and became rolled between beds during bed to bed shearing 1 ref 5

spatiotemporal variations in eruption style and magnitude at yasur volcano vanuatu part 2 extending strombolian eruption classifications in this companion study to simons et al bull volcanol 82 2020a we examine strombolian style explosive activity at yasur vanuatu over 11 weeks via seismic thermal infrared and visual observations in part 1 of this study simons et al bull volcanol 82 2020a we investigated the link between variations in the surface expression and style of volcanism at yasur in relation to vent shallow conduit and shallow magma reservoir processes now in part 2 based on the database of 4998 explosions we describe define and classify yasur s strombolian eruption styles and magnitudes and compare and contrast to stromboli and other similar centres the styles of most of yasur s explosions fit with other known strombolian eruptions but they are 2 3 times more frequent and with higher average eruption heights than at stromboli observed activity at yasur also produced more ash than at stromboli the most powerful eruptive periods are dominated by type 2a explosions ballistics and ash and type 2b ash dominated explosions a new type of strombolian style explosion was observed at yasur and is here termed a type 3 explosion they occur when vents are buried by a thick cap of loose poorly sorted pyroclastic breccia type 3 explosions begin as a series of emergent ash rich jets that rupture and fountain from the breccia cover generating prolonged jetting of ash to form vigorous low plumes the loose breccia cover apparently dissipates the violent early phase of the explosion the greatest hazard of type comes from their occurrence with little warning from a smooth crater floor without an apparent vent and after longer than typical intervals between eruptions the findings extend the observed range of strombolian explosion styles and imply that surficial vent cover and burial may influence gas slug stability and contribute to variations in ash and ballistic output

molecular organic geochemistry of a proposed stratotype for the oxfordian kimmeridgian boundary isle of skye scotland the composition of the soluble organic matter of the oxfordian kimmeridgian flodigarry shale member isle of skye scotland is presented for the first time a continuous succession of silty clays and nodular limestone beds is exposed on a rocky shore to the north of staffin bay this succession is proposed as a potential stratotype of the boundary between the oxfordian and kimmeridgian stages this paper points out the exceptional preservation and very low thermal degradation of the organic matter indeed the molecular composition is characterized by the abundance of unsaturated biomarkers hopenes and diasterenes as well as undamaged bioterpenoids ferruginol and sugiol the abundance of long chain n alkanes characterized by an odd over even predominance reveals a dominant continental contribution this is also attested to by the relatively high amounts of plant biomarkers e g ferruginol sugiol cadalene and retene which suggest a palaeovegetation largely composed of pinophytes especially cupressaceae taxodiaceae and cheirolepidiaceae on the nearest emerged lands the water column of the depositional environment was oxic in its upper part and rather dysoxic in its lower part the composition of the organic matter does not significantly change along the flodigarry shale member in other words no evolutionary events or drastic change in palaeoenvironments can be deduced from the molecular content of these sedimentary rocks and it does not allow us to support a precise location for the oxfordian kimmeridgian boundary in the succession

characteristics of puffing activity revealed by ground based thermal infrared imaging the example of stromboli volcano italy puffing i e the frequent 1 s ca release of small 0 1 10 m3 over pressurized pockets of magmatic gases is a typical feature of open conduit basaltic volcanoes worldwide despite its non trivial contribution to the degassing budget of these volcanoes and its recognized role in volcano monitoring detection and metering tools for puffing are still limited taking advantage of the recent developments in high speed thermal infrared imaging we developed a specific processing algorithm to detect the emission of individual puffs and measure their duration size volume and apparent temperature at the vent as a test case we applied our method at stromboli volcano italy studying snapshots of 1 min collected in the years 2012 2013 and 2014 at several vents in all 3 years puffing occurred simultaneously at three or more vents with variable features at the scale of the single vent a direct relationship links puff temperature and radius suggesting that the apparent temperature is mostly a function of puff thickness while the real gas temperature is constant for all puffs once released in the atmosphere puffs dissipate in less than 20 m on a broader scale puffing activity is highly variable from vent to vent and year to year with a link between average frequency temperature and volume from 136 puffs per minute 600 k above ambient temperature 0 1 m3 and the occasional ejection of pyroclasts to 20 puffs per minute 3 k above ambient 20 m3 and no pyroclasts frequent small hot puffs occur at random intervals while as the frequency decreases and size increases an increasingly longer minimum interval between puffs up to 0 5 s appears these less frequent and smaller puffs also display a positive correlation between puff volume and the delay from the previous puff our results suggest an important role of shallow bubble coalescence in controlling puffing activity the smaller and more frequent puffing at hotter vents is in agreement with the rapid rise of small gas pockets with only limited coalescence while slower rise allowing more time for coalescence leads to larger but less frequent puffing at colder vents this link between puffing style and vent thermal state points to a feedback between gas flux and magma temperature and viscosity where higher gas flux stirs and heats the magma which by getting less viscous becomes a preferential way for bubble rise such a link has implications for the monitoring of the state of the shallow conduit at open vent volcanoes as well as for determination of their total gas budget relevant for hazard forecast and environmental studies

infrasonic tremor observed at kīlauea volcano hawai i 1 infrasonic array data collected at k lauea volcano hawai i during november 12 21 2002 indicate that the active vents and lava tube system near the pu u vent complex emit almost continuous infrasound in the 0 3 10 hz frequency band the spectral content of these infrasonic signals matches well that of synchronous seismic tremor in sites protected from wind noise significant signal to noise ratios were recorded as far as 13 km from the crater of pu u the infrasonic recordings suggest that one or more tremor sources may be close to the surface in addition these results demonstrate that adequate site and instrument selections for infrasonic arrays are essential in order to obtain consistent and reliable infrasonic detections

ducks low cost thermal monitoring units for near vent deployment abstract during 1999 we designed and tested a thermal monitoring system to provide a cheap robust modular real time system capable of surviving the hostile conditions encountered proximal to active volcanic vents in november 2000 the first system was deployed at pu u o o kilauea hawai i to target persistently active vents aside from some minor problems such as sensor damage due to tampering this system remained operational until january 2004 the success of the prototype system led us to use the blueprint for a second installation at stromboli aeolian islands italy this was deployed dug into a bomb proof bunker during may 2002 and survived the april 2003 paroxysmal eruption despite being located just 250 m from the vent in both cases careful waterproofing of connectors and selection of suitable protection has prevented water damage and corrosion in the harsh atmosphere encountered at the crater rim the pu u o o system cost us 10 000 and comprises four modules sensors transmission and power hub repeater station and reception site the sensor component consists of three thermal infrared thermometers housed in pelican cases fitted with germanium arsenide selenium windows two 1 field of view fov sensors allow specific vents to be targeted and a 60 fov sensor provides a crater floor overview a hard wire connection links to a pelican case housed microprocessor modem and power module from here data are transmitted via a repeater site to a dedicated pc at the hawaiian volcano observatory here data are displayed with a delay of 3 s between acquisition and display the modular design allows for great flexibility at stromboli 1 and 15 fov sensor modules can be switched depending changes in activity style and crater geometry in addition a direct line of site to the stromboli reception center negates the repeater site requirement reducing the cost to us 5500 for a single sensor system we have also constructed self contained units with internal data loggers for us 1500 unit these have been tested at kilauea stromboli etna masaya santiaguito fuego pacaya poas soufriere hills villarrica and erta ale these instruments have proved capable of detecting thermal signals associated with 1 gas emission 2 gas jetting events 3 crater floor collapse 4 lava effusion 5 lava flow in tubes 6 lava lake activity 7 lava dome activity and 8 crater lake skin temperature

polar aromatic biomarkers in the miocene maritza east lignite bulgaria aromatic and polar compounds of lignite lithotype bitumens maritza east were analyzed diterpenoid phenols and ketophenols i e mainly ferruginol sugiol hinokione and products of their diagenetic transformations were identified as the dominant biomarkers a variety of sesquiterpenoids was present as well these compounds provided evidence for the assumption that members of the cupressaceae s 1 are the coal precursors polar triterpenoids i e lupeol lupenone adiantone and hopanones were present in subordinate quantities in the humoclarain sample these biomarkers support an input of deciduous angiosperm vegetation to the peat swamp source matter three diagenetic transformation schemes for the diterpenoid phenols ketophenols are proposed 1 ferruginol and or sugiol alteration through dehydrogenation demethylation and ring b cleavage 2 hinokione aromatization to simonellite and 3 7 ketototarol change through 7 ketototar 5 enol to 20 nor 3 oxo totara 5 10 6 dienol the identified diterpenoids demonstrated the presence of gymnospermae in the coal forming community furthermore the phenolic diterpenoids indicated a specific input of organic matter from conifers of the cupressaceae taxodiaceae or podocarpaceae as the most abundant trees in the coal forming swamp

identification of variable convective regimes at erta ale lava lake abstract during february 17 19 2002 we collected a combined thermal and seismic data set for persistent lava lake activity at erta ale volcano ethiopia these data indicate that the lake cycled between periods characterized by low 0 01 0 08 m s 1 and high 0 1 0 4 m s 1 surface velocities typically lasting tens to hundreds of minutes these periods of high and low velocity motion define periods of vigorous and sluggish convection respectively spectral analysis revealed that vigorous convection periods were characterized by high frequencies and energies in the thermal data and an increased presence of high frequency energy in the seismic data the data show that vigorous periods were characterized by formation of hot short lived plastic crusts and sluggish periods by cooler longer lived brittle crusts here the higher transit velocity across the lake surface from upwelling zones of crust formation to downwelling zones of crust destruction during the vigorous periods decreases the crust lifetime this in turn decreases the total cooling and thickening experienced by a plate of crust moving across the lake surface two scenarios can be envisaged to explain such convection cycles the first relates variable convection rates to changes in the volume flux and rheology of magma entering the lake in the second cyclic convection is set up by the generation of convective instabilities within the lake in this case cooling of a surface layer generates a slow moving viscous increasingly dense convection layer at the lake surface which is consumed and replaced during overturn

volcano surveillance using infrared cameras abstract volcanic eruptions are commonly preceded accompanied and followed by variations of a number of detectable geophysical and geochemical manifestations many remote sensing techniques have been applied to tracking anomalies and eruptive precursors and monitoring ongoing volcanic eruptions offering obvious advantages over in situ techniques especially during hazardous activity whilst spaceborne instruments provide a distinct advantage for collecting data remotely in this regard they still cannot match the spatial detail or time resolution achievable using portable imagers on the ground or aircraft hand held infrared camera technology has advanced significantly over the last decade resulting in a proliferation of commercially available instruments such that volcano observatories are increasingly implementing them in monitoring efforts improved thermal surveillance of active volcanoes has not only enhanced hazard assessment but it has contributed substantially to understanding a variety of volcanic processes drawing on over a decade of operational volcano surveillance in italy we provide here a critical review of the application of infrared thermal cameras to volcano monitoring following a summary of key physical principles instrument capabilities and the practicalities and methods of data collection we discuss the types of information that can be retrieved from thermal imagery and what they have contributed to hazard assessment and risk management and to physical volcanology with continued developments in thermal imager technology and lower instrument costs there will be increasing opportunity to gather valuable observations of volcanoes it is thus timely to review the state of the art and we hope thereby to stimulate further research and innovation in this area

acoustic sounder measurements of the vertical velocity of volcanic jets at stromboli volcano we have used a sodar acoustic doppler sounder to characterize the behavior of volcanoes and in particular to measure the vertical velocities of volcanic jets we have analyzed more than 100 explosions on stromboli volcano eolian islands first results show vertical speeds close to the vent ranging from 20 m s to 80 m s the uncertainty in the measurements is close to 10 due mainly to the inaccurate knowledge of the sound speed in volcanic jets this is small compared to other volcanological methods this method is well suited for monitoring temporal variations during an eruption and should be particularly interesting for the study of the eruptive dynamics of lava fountains the doppler spectrum in explosions appears to be related to different types of echoes and contains information on particle sizes in the jet

sulfur and halogen gases at masaya caldera complex nicaragua total flux and variations with time santiago crater of masaya caldera complex near managua nicaragua entered a phase of intense magmatic degassing in late 1979 the flux of so2 increased rapidly from a previous average of 380 t d 1 to approximately 1200 t d 1 in february 1980 we report on results of a study of the gas flux and geochemistry conducted as part of a broader interdisciplinary study of the volcano and its impact on the adjacent environment masaya is an unusual volcano because of its low shield like form consistent tholeiitic basaltic composition frequent activity and especially because of the approximately 25 year cycle of major non eruptive degassing crises we have used a combination of techniques involving remote sensing using a correlation spectrometer cospec of the flux of so2 and direct filter sampling of the ratios of the sulfur and halogen gases and aerosols to quantify the flux of all of these species the three stage filters successively trap aerosols halogen acid gases and sulfur dioxide and are analyzed by ion chromatography we have used the ratios of various species with the cospec measurements of the flux of so2 to calculate that the average flux of so2 is 1275 t d 1 hcl is 830 t d 1 hf is about 16 t d 1 and hbr is at most 1 t d 1 h2s and so4 are only minor sulfur species the flux of so2 and hcl represents the largest reported noneruptive sustained volcanic release of these species in the world masaya contributed 7 of the total so2 estimated to have been released by volcanoes worldwide in 1981 the flux of so2 has declined by about 9 each year since 1979 and can be modeled as a first order kinetic rate law with a decay constant of approximately 0 04 yr 1 approximately 2 2 106 tons of so2 has been released between september 1979 and september 1985 the ratio s cl has declined more rapidly than the flux of so2 reflecting the greater solubility of hcl than so2 in the magma the so2 flux at santiago varies more widely within a single day than observed at other degassing volcanoes and may be controlled at least in part by effects of the solid earth tide an area larger than 500 km2 has been severely impacted downwind of the volcano downwind ground level concentrations of so2 of 0 25 ppm are frequently encountered acid rain unusually chloride rich has a ph as low as 2 63 s cl ratios in the gas plume increase downwind probably as a result of the high solubility and dry deposition velocity of hcl preliminary analyses of primary concentrations of sulfur and chlorine in the magma of the present lava lake are used to calculate that at least 1 2 km3 has been completely degassed with respect to sulfur to provide the observed flux this implies that 10 km3 have been degassed by previous crises in the past century and further suggests a magma supply rate of approximately 0 1 km3 yr comparable with kilauea or etna volcanoes during historic time only two lava flows have been extruded implying an unusually low ratio of extrusion intrusion of only 0 0007

trace elements in the particulate phase of the plume of masaya volcano nicaragua masaya volcano nicaragua has been passively degassing since 1993 this gas crisis provides a unique opportunity for investigating the degassing of magmatic volatiles here we studied the chemical composition of the volcanic particulate phase collected directly from the plume the objective was to gain new insights into the volatilities and emission rates of trace elements the results indicate enrichments in the aerosol phase of all analyzed trace elements including not only those known to be volatile such as cu and te but also elements considered as refractory such as rare earth elements rees and th rees were fractionated with a significant enrichment of light rare earth elements lrees over heavy rare earth elements hrees this pattern suggests degassing of lrees as chlorides in general the emission of most trace elements in volcanic plumes is governed by the primary degassing of chloride compounds however sem eds data and chemical analysis of aerosol filters allow us to state that trace elements can also be released as sulphate and chloro sulphate compounds the trace element emission rates at masaya are significant and place this volcano as a major gas emitter however for some elements like cu masaya s contribution to the global volcanic flux seems disproportionate probably pointing to the poor dataset available for other degassing volcanoes

carbon dioxide dynamics in kelud volcanic lake 1 in november 2007 the extrusion of a new lava dome evaporated kelud volcanic lake in java indonesia four months before a detailed echo sounding survey of the volcanic lake coupled to floating accumulation chamber measurements detected abnormally high carbon dioxide emissions it constituted the earliest sign of the volcanic unrest well before any other monitored parameter co2 flux is quantified using an empirical equation based on the volume of bubbles backscattered in the water column its comparison with the fluxes retrieved from the floating chamber method better constrain carbon dioxide dynamics in the volcanic lake it reveals that 70 of the carbon dioxide enters the lake in a dissolved form while the remaining 30 is supplied to the lake on a gaseous state almost three quarter of the ascending bubbles dissolve in the water column leaving the majority of the 330 tons day 1 of carbon dioxide diffusing at the air water interface

gravity changes and passive so2 degassing at the masaya caldera complex nicaragua an understanding of the mechanisms responsible for persistent volcanism can be acquired through the integration of geophysical and geochemical data sets by interpreting data on micro gravity ground deformation and so2 flux collected at masaya volcano since 1993 it is now clear that the characteristically cyclical nature of the activity is not driven by intrusion of additional magma into the system rather it may be due in large part to the blocking and accumulation of gas by restrictions in the volcano substructure the history of crater collapse and formation of caverns beneath the crater floor would greatly facilitate the trapping and storage of gas in a zone immediately beneath san pedro and the other craters another mechanism that may explain the observed gravity and gas flux variations is the convective overturn of shallow pre existing degassed cooled dense magma that is replaced periodically by lower density hot gas rich magma from depth buoyant gas rich magma rises from depth and is emplaced near the surface resulting in the formation and fluctuation of a low density gas rich layer centred beneath nindiri and santiago craters as this magma vigorously degasses it must cool increase in density and eventually sink five stages of activity have been identified at masaya since 1853 and the most recent data suggest that the system may have been entering another period of reduced degassing in 2000 this type of analysis has important implications for hazard mitigation because periods of intense degassing are associated with poor agricultural yields and reduced quality of life a better understanding of persistent cyclically active volcanoes will allow for more effective planning of urban development and agricultural land use

the initial phases of the 2008 2009 mount etna eruption a multidisciplinary approach for hazard assessment accepted for publication in journal of geophysical research copyright 2010 american geophysical union

a comparison of field and satellite derived thermal flux at piton de la fournaise implications for the calculation of lava discharge rate we present thermal measurements made by high spatial resolution ground based a hand held thermal camera and low spatial resolution space based modis instruments for a lava flow field active during the last phase of the may july 2003 eruption at piton de la fournaise la reunion multiple oblique ground based thermal images were merged to provide full coverage of the flow field these were then corrected for path length attenuation and orthorectified allowing the at surface radiance emitted by the flow field to be estimated comparison with the radiance recorded by the modis sensors during the eruption reveals that for clear sky conditions and moderate to low viewing angles satellite zenith 40 the satellite measurements represent 90 of the at surface radiance and thus represent valuable data for quantifying volcanic thermal anomalies nevertheless extreme viewing geometries and the presence of clouds strongly affect the radiance reaching the sensor and affected data from 94 of the overpasses ground based thermal data were used to investigate an empirical relationship between the radiant heat flux and lava discharge rate during the emplacement of pahoehoe flows while the average radiation temperature for flow surface that were 6 24 h old ranged between 500 k and 625 k the ratio between radiative heat flux and time averaged lava discharge rate tadr ranged between 1 5 108 j m 3 and 3 5 108 j m 3 this relationship was used to estimate tadr values from optimal modis data and produced results in line with those obtained from gps surveys coppola et al 2005 our results underscore the importance of ground based thermal analysis for the interpretation of satellite measurements particularly in terms of calculating discharge rate trends

polar aromatic biomarkers of miocene aged chukurovo resinite and correlation with a progenitor macrofossil abstract functionalised aromatic constituents of chukurovo resinite are compared here with the chemical composition of a macrofossil assigned paleobotanically as taxodium dubium sternb heer terpenoids and lipids of fossil wood tissue embedded in a clay sediment were extracted and analyzed for comparison the information was interpreted in relation to the biomarker compositions of different conifer families as well as to the effects of contamination by inward migration of organic matter from the adjacent sediments many of identified geolipids i e alkanes alkanols alkan 2 ones and steranes triterpanes have no chemosystematic value because they are ubiquitous in the plant kingdom ferruginol sugiol and products of their diagenetic transformations were identified as the dominant specific biomarkers in the resinite ferruginol and its analogues were the most abundant diterpenoids in taxodium dubium sample thus the biomarker composition of the extractable matter of the resinite strongly suggests that species of cupressaceae contributed significantly to the chukurovo paleoenvironment

high frame rate thermal imagery of strombolian explosions implications for explosive and infrasonic source dynamics 1 explosive activity at stromboli volcano is analyzed using a high frame rate 50 hz thermal camera and differential pressure transducers we develop a thermal image based decomposition method to derive vertical and horizontal exit velocities of the explosive cloud peak vertical velocity ranges between 23 and 203 m s slightly higher than previous estimates and rapidly decreasing to a constant value of 30 50 m s within the first 0 1 s plume velocities are consistent with an elongated cloud expanding much faster vertically than horizontally and indicating the interaction with the conduit wall considering a vent radius of 2 m we estimate a volumetric flux of 200 600 m3 s which converts to total volumes of gas particles of 103 104 m3 for a single eruption these volumes are proportional to the thermal energy recorded by the camera providing a means to convert thermal radiance to volumes comparing the thermal onset of the explosions with the arrival time of the acoustic pressure we demonstrate that infrasound is propagating 0 14 1 7 s ahead of the explosive front the time difference between thermal and acoustic onsets constrains the infrasonic source within the conduit at 15 35 m below the crater rim peak amplitudes of acoustic pressure show a power law relationship p u2 with the exit vertical velocities consistent with the energy balance of a two phase flow rapidly accelerated in the conduit by gas decompression our results support monopole isotropic acoustic radiation of a source embedded within the conduit walls and indicate that explosive dynamics undergo strong accelerations of 103 104 m s2

automated high time resolution measurements of so2 flux at soufriere hills volcano montserrat we report here the first results from an automated telemetered uv scanning spectrometer system for monitoring so2 emission rates at soufriere hills volcano montserrat two spectrometers receive light by way of a motor driven stepping prism and telescope in order to make vertical scans of the volcanic plume spectral data from these spectrometers situated 2 800 m apart and 4 500 m from the volcano are relayed back to the observatory every 4 5 s via radio modems a full scan of the plume is accomplished every 1 6 min by the time synchronised spectrometers and a so2 emission rate is calculated using the so2 slant concentrations scan angles and plume speeds estimated from the wind speed from a telemetered weather station near to the volcano the plume s position and dimensions are calculated using the angular data from the two spectrometers the plume height varies significantly diurnally and seasonally and is important in order to minimise the error on so2 emission rates the new scanning system scanspec provides so2 emission rates from 08 00 to 16 00 h local time every day preliminary results highlight a number of features of the so2 time series and plume dynamics and give our first indications of the errors and limits of detection of this system so2 emission rates vary widely on all time scales minutes days months this new system has already provided the first real and consistent indication that so2 emission rates vary on a minutes to hours basis which can be correlated with volcanic activity for example rockfall and pyroclastic flow activity it is anticipated that this system at soufriere hills will yield information on shallow processes occurring on short time scales periods of minutes to hours as well as deep processes relating to magma supply rates which will be associated with longer wavelength so2 signals of weeks to months

terpenoid composition and botanical affinity of cretaceous resins from india and myanmar abstract fossil resins from the cretaceous sediments of meghalaya india and kachin myanmar burma were analysed using curie point pyrolysis gas chromatography mass spectrometry and thermochemolysis gas chromatography mass spectrometry to help elucidate their botanical source the major pyrolysis products and methyl esterified thermochemolysis products of both the resins were abietane and labdane type diterpenoids with minor amount of sesquiterpenoids the thermochemolysis products also included methyl 16 17 dinor callitrisate methyl 16 17 dinor dehydroabietate and methyl 8 pimaren 18 oate the latter two from just the myanmarese resin the exclusive presence of both labdane and abietane diterpenoids and the lack of phenolic terpenoids may suggest that the studied cretaceous resins were derived from pinaceae pine family conifers

terpenoid composition of fossil resins from western india new insights into the occurrence of resin producing trees in early paleogene equatorial rainforest of asia abstract the terpenoid composition of well preserved fresh and oxidized fossil resins ambers from early paleogene lignite bearing sequences of india have been examined using gas chromatography mass spectrometry for determining their botanical origin the samples were collected from two sedimentary basins viz barmer akli formation and bikaner nagaur palana formation western india the total extracts of the studied ambers are represented by hydronaphthalenes sesquiterpenoids and significant occurrence of diterpenoids such terpenoid distribution is typical for gymnosperm especially conifer derived sources the diterpenoids are comprised of majorly abietane phyllocladane kaurane pimarane isopimarane and podocarpane class compounds tertracyclic diterpenoids such as 18 norkauranes ent 16 h kaurane and 16 h phyllocladane and a rearranged tricyclic diterpenoid rosane are detected in the fossil resins from barmer basin the occurrence of tetracyclic diterpenoids and rosane together with 8 13 dimethyl 16 norpodocarpa 6 ene suggests that podocarpaceae family is the possible source of the ambers however chemotaxonomic assignment at family level for the fossil resin from bikaner nagaur basin is difficult due to the absence of source specific diterpenoids previous reports had documented the occurrence of angiosperm derived dammar resins from early paleogene sediments of india dutta et al 2009 rust et al 2010 the present study suggests that the early paleogene resins of the equatorial rainforests were not always represented by the dammar resins derived from dipterocarpaceae a family of angiosperm some of them were also contributed by the conifers

mesozoic extension in the basque cantabrian basin n spain contributions from ams and brittle mesostructures abstract in this work we analyse and check the results of anisotropy of magnetic susceptibility ams by means of a comparison with palaeostress orientations obtained from the analysis of brittle mesostructures in the cabuerniga cretaceous basin located in the western end of the basque cantabrian basin north spain the ams data refer to 23 sites including triassic red beds jurassic and lower cretaceous limestones sandstones and shales these deposits are weakly deformed and represent the syn rift sequence linked to basins formed during the mesozoic and later inverted during the pyrenean compression the observed magnetic fabrics are typical of early stages of deformation and show oblate triaxial and prolate magnetic ellipsoids the magnetic fabric seems to be related to a tectonic overprint of an original compaction sedimentary fabric most sites display a ne sw magnetic lineation that is interpreted to represent the stretching direction of the early cretaceous extensional stage of the basin without recording of the tertiary compressional events except for sites with compression related cleavage brittle mesostructures include normal faults calcite and quartz tension gashes and joints related to the extensional stage the results obtained from joints and tension gashes show a dominant n s to ne sw and secondary nw se extension direction paleostresses obtained from fault analysis right dihedra and stress inversion methods indicate nw se to e w and n s extension direction the results obtained from brittle mesostructures show a complex pattern resulting from the superposition of several tectonic processes during the mesozoic linked to the tectonic activity related to the opening of the bay of biscay during the early cretaceous this work shows the potential in using ams analysis in inverted basins to unravel its previous extensional history when the magnetic fabric is not expected to be modified by subsequent deformational events brittle mesostructure analysis seems to be more sensitive to far field stress conditions and record longer time spans whereas ams records deformation on the near distance during shorter intervals of time

the nasa volcano sensor web advanced autonomy and the remote sensing of volcanic eruptions a review abstract the volcano sensor web vsw is a globe spanning net of sensors and applications for detecting volcanic activity alerts from the vsw are used to trigger observations from space using the earth observing 1 eo 1 spacecraft onboard eo 1 is the autonomous sciencecraft experiment ase advanced autonomy software using ase has streamlined spacecraft operations and has enabled the rapid delivery of high level products to end users the entire process from initial alert to product delivery is autonomous this facility is of great value as a rapid response is vital during a volcanic crisis ase consists of three parts 1 science data classifiers which process eo 1 hyperion data to identify anomalous thermal signals 2 a spacecraft command language and 3 the continuous activity scheduling planning execution and replanning casper software that plans and replans activities including downlinks based on available resources and operational constraints for each eruption detected thermal emission maps and estimates of eruption parameters are posted to a website at the jet propulsion laboratory california institute of technology in pasadena ca selected products are emailed to end users the vsw uses software agents to detect volcanic activity alerts generated from a wide variety of sources on the ground and in space and can also be easily triggered manually

the oldest record of ediacaran macrofossils in gondwana 563 ma itajai basin brazil abstract the avalon biota ediacaran period 570 559 ma marks the first appearance of macroscopic and complex benthic communities in the fossil record this assemblage is known from a few localities worldwide mainly in canada and england here we report for the first time the presence of ediacaran macrofossils in deposits of similar age from gondwana itajai basin southern brazil our new radiometric date 563 ma indicates that the itajai basin can be chronocorrelated with the classic avalonian deposits and thus represents one of the oldest records of the ediacaran biota in gondwana we describe the presence of the ediacaran genus palaeopascichnus as well as discs aspidella and nimbia and other problematic forms contrary to the deep marine macroorganisms of the avalon assemblage the itajai fossils are associated with abundant and exceptionally preserved three dimensional microbial mats and microbially induced sedimentary structures miss in relatively shallow settings upper slope and distal delta front deposits in this sense the itajai biota could represent early adaptations of benthic macrobiota to the shallower and more photic environments that characterize the later white sea assemblage

volcanology 2020 how will thermal remote sensing of volcanic surface activity evolve over the next decade abstract volcanological remote sensing spans numerous techniques wavelength regions data collection strategies targets and applications attempting to foresee and predict the growth vectors in this broad and rapidly developing field is therefore exceedingly difficult however we attempted to make such predictions at both the american geophysical union agu meeting session entitled volcanology 2010 how will the science and practice of volcanology change in the coming decade held in december 2000 and the follow up session 10 years later looking backward and forward volcanology in 2010 and 2020 in this summary paper we assess how well we did with our predictions for specific facets of volcano remote sensing in 2000 the advances made over the most recent decade and attempt a new look ahead to the next decade in completing this review we only consider the subset of the field focused on thermal infrared remote sensing of surface activity using ground based and space based technology and the subsequent research results this review keeps to the original scope of both agu presentations and therefore does not address the entire field of volcanological remote sensing which uses technologies in other wavelength regions e g ultraviolet radar etc or the study of volcanic processes other than the those associated with surface mostly effusive activity therefore we do not consider remote sensing of ash gas plumes for example in 2000 we had looked forward to a golden age in volcanological remote sensing with a variety of new orbital missions both planned and recently launched in addition exciting field based sensors such as hand held thermal cameras were also becoming available and being quickly adopted by volcanologists for both monitoring and research applications all of our predictions in 2000 came true but at a pace far quicker than we predicted relative to the 2000 2010 timeframe the coming decade will see far fewer new orbital instruments with direct applications to volcanology however ground based technologies and applications will continue to proliferate and unforeseen technology promises many exciting possibilities that will advance volcano thermal monitoring and science far beyond what we can currently envision

on the transition from strombolian to fountaining activity a thermal energy based driver since 1999 mount etna s italy south east crater system has been characterised by episodic lava fountaining each episode is characterised by initial strombolian activity followed by transition to sustained fountaining to feed high effusion rate lava flow here we use thermal infrared data recorded by a permanent radiometer station to characterise the transition to sustained fountaining fed by the new south east crater that developed on the eastern flank of the south east crater starting from january 2011 we cover eight fountaining episodes that occurred between 2012 and 2013 we first developed a routine to characterise event waveforms apparent in the precursory strombolian phase this allowed extraction of a database for thermal energy and waveform shape for 1934 events we detected between 66 and 650 events per episode with event durations being between 4 and 55 s in total 1508 78 of the events had short waxing phases and dominant waning phases event frequency increased as climax was approached events had energies of between 3 0 106 and 5 8 109 j with rank order analysis indicating the highest possible event energy of 8 1 109 j to visualise the temporal evolution of retrieved parameters during the precursory phase we applied a dimensionality reduction technique results show that weaker events occur during an onset period that forms a low energy sink the transition towards fountaining occurs at 107 j where subsequent events have a temporal trend towards the highest energies and where sustained fountaining occurs when energies exceed 109 j such an energy based framework allows researchers to track the evolution of fountaining episodes and to predict the time at which sustained fountaining will begin

a total volatile inventory for masaya volcano nicaragua nerc project magma dynamics at persistently degassing basaltic volcanoes a novel approach to linking volcanic gases and magmatic volatiles within a physical model ne f004222 1 and ne f005342 1

continuous monitoring of high temperature fumaroles on an active lava dome volcan colima mexico evidence of mass flow variation in response to atmospheric forcing rapid multichannel monitoring of fumaroles on volcan colima mexico provides new insight into the time scales and magnitudes of fumarole temperature variation temperatures in five fumaroles all located along a single fracture cutting the summit lava dome of the volcano were monitored at 20 min intervals between may 1991 and may 1992 measurements were made using a programmable data logger deployed near the fumarole field and data were radiotelemetered to a nearby volcano observatory at regular intervals mean fumarole temperatures varied between 350 c and 550 c statistical analysis of these time series shows that significant diurnal variation occurs in each fumarole magnitudes of these daily fluctuations are generally between 25 c and 50 c although larger amplitude variations occur especially in cooler fumaroles simultaneous monitoring of atmospheric pressure at the fumaroles indicates that these variations in temperature are inversely correlated with barometric pressure these observations indicate that fumarole temperatures respond to atmospheric forcing a numerical model developed to explore the dependence of fumarole temperature on mass flow demonstrates that many aspects of observed temperature variation are accounted for by mass flow variation resulting from small changes in barometric pressure the relationship between mass flow and fumarole temperature is nonlinear the response of fumarole temperatures to a given change in mass flow is greatest in fumaroles with low mass flow and cool temperatures the nature of this dependence is little affected by fumarole geometry for the cases considered continuous measurement of fumarole temperatures may be an effective means of monitoring local mass flow on volcanoes at volcan colima average temperatures changed by less than 100 c during the 1 year sampling period during and immediately following effusive activity changes in degassing were abrupt and inconsistent along the length of the fracture following this period temperatures decreased gradually and there was a higher degree of correlation between fumaroles the method described here represents a substantial improvement over traditional fumarole monitoring techniques because subtle variation can be quickly identified using standard statistical techniques and the method provides regular information about thermal activity on a volcano minimizing the hazards normally associated with the collection of these data on a regular basis

sesqui and diterpenoid biomarkers preserved in taxodium rich oligocene oxbow lake clays weisselster basin germany several diterpenoids of the abietane pimarane and phyllocladane type and three cadalanetype sesquiterpenoids have been identified in the organic solvent extracts of lower oligocene clay sediments haselbach strata saxony germany the sediment contains needles and cone scales of a fossil taxodium species which represents the only conifer in the samples a clear correlation between the observed conifer biomarkers and taxodium is evident apart from diterpenoids detected previously in other sediments a new diaromatic totarane diterpenoid is reported in isolated fossil and recent taxodium needles and cone scales as well as in the haselbach clays a phenolic diterpenoid of the abietane type ferruginol has been identified the results indicate that the taxodium rich clay samples contain several diterpenoids which so far have been used as biomarkers for other conifer families and thus the chemotaxonomical use of diterpenoid biomarkers for the differentiation of fossil conifer families has to be revised

hydrocarbon composition of russian amber from the voznovo lignite deposit and sakhalin island abstract amber of different color and fluorescence has recently been found in a lignite seam in the zerkal nenskaya depression primorsky krai russia in this deposit the amber is associated with abundant charcoal and fusain fragments in the host rocks beside three composite samples of different color from the lignite and one composite amber sample from the sakhalin island has been included in this study for comparison based on previous fluorescence and fluorescence excitation measurements the blue glow of amber has been related to the fluorescent aromatic hydrocarbon perylene although ftir study of the russian blue amber has not found any distinct signature of this compound the present analyses using gas chromatography mass spectrometry have also identified no perylene in any of the four russian amber samples the hydrocarbon fractions of the extractable organic matter from the ambers are dominated by c18 to c20 diterpenoids of the labdane abietane pimarane phyllocladane and kaurane types their biomarker composition is consistent with the proposed origin from gymnosperms of the families pinaceae cupressaceae and or taxodiacceae the cause for the blue amber glow could not be clarified based on the commonly used methods of hydrocarbon composition study

measuring and interpreting heat fluxes from shallow volcanic bodies using vertical temperature profiles a preliminary test to test the potential of heat flux prospecting in active volcanic areas using shallow temperature data taken along vertical profiles we carried out two thermal profile surveys one not far from yasur cone on tanna island and another inside the caldera of ambrym new hebrides arc southwestern pacific the basic steady heat flux of internal volcanic origin was determined taking into account both conductive and convective heat transfers at both locations there exists over small distances significant differences in the heat flux these differences correspond to shallow sources of heat the use of a network of vertical profiles allowed a heat flux mapping b location of shallow volcanic heat sources and c observation of the detailed structure of the heat release at quiescent but active volcanoes

vascular plant biomarkers as proxies for palaeoflora and palaeoclimatic changes at the dogger malm transition of the paris basin france abstract vascular plant biomarkers are used here as a chemostratigraphic tool for tracing both palaeoflora and palaeoclimatic changes during the callovian and oxfordian in the paris basin the retene cadalene ratio shows low values in claystones from the middle callovian to the end of the lower oxfordian then increases drastically from the end of the lower oxfordian cordatum zone synchronously with the progressive development of the oxfordian carbonate platform the relative proportion of retene a conifer biomarker is strongly correlated with the abundance of some of its diagenetic precursors and with saturated diterpanes some of these are very common and abundant in the pinaceae family while specific markers for non pinaceae conifers are not detected thus the increase in the retene cadalene ratio around the cordatum zone reflects the rising proportion of pinaceae on the london brabant massif which was the nearest land from the locations studied as pinaceae show many morphological adaptations to dry climate compared to the other plants reported in the jurassic taphofloras of the paris basin their increasing proportion indicates an increasing aridity this climatic change is also supported by published geochemical palaeobiogeographical palynological palaeobotanical and mineralogical data a comparable increase in the relative proportion of retene was also described for the oxfordian of western australia which could be an argument for a worldwide increase in aridity at the end of the lower oxfordian

effusive to explosive transition during the 2003 eruption of stromboli volcano the persistent explosive activity of stromboli volcano italy ceased in december 2002 and correlated with the onset of a seven month long effusive eruption on the volcano flank from new vents that opened just below the summit craters we intensively monitored this effusive event collecting and interpreting in real time an extensive multiparametric geophysical data set the resulting data synergy allowed detailed insights into the conduit dynamics that drove the eruption and the transition back to the typical strombolian activity we present a direct link between gas flux magma volume flux and seismicity supporting a gas driven model whereby the balance between gas flux and gas overpressure determines whether the system will support effusive or explosive activity this insight enabled us to monitor the migration of the magma column up the conduit and to explain the onset of explosive activity

application of new diterpane biomarkers to source biodegradation and mixing effects on central llanos basin oils colombia llanos basin oils have been commonly attributed to the prolific upper cretaceous age source formations outcropping in the eastern cordillera recently however variable oleanane indices have been reported for llanos oils suggesting a contribution from tertiary source sequences largely on the basis of the presence of high relative abundance of oleanane a tertiary age diagnostic biomarker a homologous series of 25 norhopanes in many central llanos basin oils indicates that heavy biodegradation is particularly common to the initial oil charging reservoirs from upper cretaceous marine sources one homologue 20s 25 norhomohopane c30 25 norhopane co elutes with oleanane and may thus contribute to the peak attributed to oleanane also confusing the source identification is the possibility that some cretaceous facies also contain oleanane three plant diterpanes which may be isomers of fichtelite and are common to the central llanos oils have been observed in an eocene source rock sample but not in cretaceous rocks or oils providing additional strong evidence for a tertiary contribution to some llanos basin oils in mixed oils with low to moderate oleanane contents and with a strong co eluting c30 25 norhopane the fichtelite isomers are the more reliable indicators of tertiary source input

carbon oxygen and strontium isotope geochemistry of proterozoic carbonate rocks of the vindhyan basin central india abstract carbon oxygen and strontium isotope compositions of carbonate rocks of the proterozoic vindhyan supergroup central india suggest that they can be correlated with the isotope evolution curves of marine carbonates during the latter proterozoic the carbonate rocks of the lower vindhyan supergroup from eastern son valley and central vindhyan sections show 13c values of 0 v pdb and those from rajasthan section are enriched up to 2 8 in contrast the carbonate rocks of the upper vindhyan succession record both positive and negative shifts in 13c compositions in the central vindhyan section the carbonates exhibit positive 13c values up to 5 7 and those from rajasthan show negative values down to 5 2 the 18o values of most of the carbonate rocks from the vindhyan supergroup show a narrow range between 10 and 5 v pdb and are similar to the best preserved 18o compositions of the proterozoic carbonate rocks in the central vindhyan and eastern son valley sections carbonates from the lower vindhyan exhibit best preserved 87sr 86sr compositions of 0 7059 6 which are lower compared to those from rajasthan 0 7068 4 the carbonates with positive 13c values from upper vindhyan are characterized by lower 87sr 86sr values 0 7068 2 than those with negative 13c values 0 7082 6 a comparison of c and sr isotope data of carbonate rocks of the vindhyan supergroup with isotope evolution curves of the latter proterozoic along with available geochronological data suggest that the lower vindhyan sediments were deposited during the mesoproterozoic eon and those from the upper vindhyan represent a neoproterozoic interval of deposition

molecular composition and chemosystematic aspects of cretaceous amber from the amazonas araripe and reconcavo basins brazil amber occurrences in brazil are rare in this regard the molecular composition of three such fossil resin samples from brazilian cretaceous sedimentary basins has been analyzed to determine the botanical origin of the resins the samples were collected from the amazonas alter do chao formation araripe santana formation crato member and reconcavo maracangalha formation caruacu member basins the mono sesqui and diterpenoids in the extracts were used as chemosystematic markers when compared with terpenoids in extant conifers the compounds were mainly diterpenoids and their degradation products from the labdane podocarpane pimarane and isopimarane classes in addition to paraffins methoxyphenols and carboxylic acids tetracyclic diterpenoids such as phyllocladane kaurenol and kauranol were also present the biomarker compositions are certainly typical for conifers and given the absence of triterpenoids and diterpenoids such as ozic acid angiosperms can be excluded as a botanical source the absence of phenolic diterpenoids ferruginol totarol and their derivatives excludes podocarpaceous affinities for the ambers from the amazonas and araripe basins the fossil records of the embedding sediments e g araucariaceae pollen and leaves support the proposal of an araucariacae origin for these ambers but cupressaceae and cheirolepidiaceae cannot be excluded on the other hand the presence of phyllocladane and kaurane derivatives is evidence for araucariaceae or podocarpaceae origins for the amber from the reconcavo basin but cupressaceae cannot be excluded