structural boron as factor controlling illite crystallinity in a mud volcano environment northern apennine italy abstract mud extrusion is a well known phenomenon whereby fluid rich fine grained sediments ascend within a lithological succession due to their buoyancy in this study of the terrestrial mud volcanism associated to an active thrusted area in the northern apennines we investigated the effect of boron incorporation in illite crystalline lattice a significant variation was recorded on the investigated mud samples with respect to both the amount of fixed boron 118 529 g g and the full width at half maximum height value fwhm of illite 0 29 0 62 2 we attribute these variations to the interaction between boron rich formation waters and the silty clayey lithologies of the local sedimentary succession the lack of any geographical correlation between the selected geochemical and mineralogical parameters is likely due to intensive thrust and fold deformation of the study area comparison of fwhm values with those from dellisanti et al 2008 santerno succession northern apennine lead us to suggest that application of fwhm as a depth indicator could be misleading within b rich hydro geological environments

boron in an onshore mud volcanic environment case study from the kerch peninsula the caucasus continental collision zone abstract numerous mud volcanoes mvs of the kerch peninsula emit water and mud with extreme boron enrichment boron content correlates with the burial depth of the source oligo miocene maykop mudrocks yielding the highest boron contents in illite dominated mud up to 900 1500 ppm b and clay fractions found in the bulganak mv which represent the deep endmembers up to 3 5 km in the kerch peninsula smectite dominated mud and clay fractions from shallow depths 1 1 5 km at small mvs are poorer in both illite and boron 66 250 ppm b enrichment of the parent shale and diagenetically driven smectite illitization and dewatering may be main prerequisites for boron enrichment in mvs the majority of both cl hco3 na and hco3 cl na highly evolved saline mv waters sampled in large mvs are enriched in 18o 18o 9 8 to 14 5 vsmow and d d 30 to 4 vsmow isotopes being also rich in boron average 650 ppm waters of small mvs with shallow roots are poorer in 18 18o 3 6 to 6 1 vsmow and b average 130 ppm mv waters are mainly related to diagenetically altered basinal water diluted by 18o enriched fresh water released during smectite illitization the fluid generation temperatures inferred to be mg li 34 to 117 correspond to source depths of 1 0 to 3 5 km at 30 35 c km regional geothermal gradients in the hot season mv waters reach a salinity of 40 70 g l total dissolved solids and precipitate halite ulexite borax and tincalconite at the bulganak mv field there is a unique accumulation of mv related non marine borates such borate deposits can form at the following essential conditions venting of b rich mv waters environment akin to playa lake long dry and hot seasons evaporation and ensuing increased boron concentration in shallow close mv pools ph of mv water between 8 5 and 9 5 low permeability of clayey mud cover

heavy carbon travertine related to methane generation a case study of the big tarkhan cold spring kerch peninsula crimea abstract the big tarkhan cold spring is located within the bulganak zone of mud volcanism in the northern kerch peninsula crimea the spring waters mainly have cl hco 3 na ca chemistry and temperatures from 18 to 23 c active travertine deposition at the site produces abundant calcite and minor amounts of siderite halite tincalconite trona gaylussite northupite and amorphous iron hydroxides calcite contains the impurities of 0 26 2 16 wt mgo up to 0 87 wt feo 0 15 0 73 wt sro 0 28 0 98 bao up to 0 43 wt mno and 0 09 0 60 na 2 o active travertines are depleted in ree ree 2 6 4 8 ppm compared to the inactive ones the kerch travertine calcite shows unusual carbon and oxygen isotope compositions 8 1 12 5 vpdb 13 c and 10 1 12 9 vpdb 18 o their isotopic and trace element signatures including ree patterns suggest their relation to basinal waters and origin from the organic rich clayey maikop fm which is the principal source rock of the area the big tarkhan travertine deposits are associated with thermogenic methane production

fluid expulsion from the dvurechenskii mud volcano black sea part i fluid sources and relevance to li b sr i and dissolved inorganic nitrogen cycles significant sediment ocean chemical fluxes are produced by the expulsion of sedimentary fluids at continental margins although such fluxes could play a role in global geochemical cycles few quantitative estimates of their global or even regional significance exist we carried out a pore water geochemical study of fluids expelled from the dvurechenskii mud volcano dmv in the black sea with the aim of understanding the role played by mud volcanoes in black sea geochemical cycles the dmv is presently expelling highly saline fluids particularly enriched in geochemically important species such as li 1 5 mm b 2 17 mm ba2 0 57 mm sr2 0 79 mm i 0 4 mm and dissolved inorganic nitrogen din 22 mm a combination of geochemical indicators shows that this geochemical signature was acquired via organic matter and silicate alteration processes in the subsurface down to 3 km depth and near surface gas hydrate formation we used a simple transport model to estimate the benthic fluxes of these solutes at the dmv our results show that the dmv is expelling fluids at a rather low seepage rate 8 25 cm year 1 resulting in a total water flux of 9 4 10 5 km3 year 1 this gentle regime of fluid expulsion results in li b sr2 i and din fluxes between 3 8 104 and 2 1 106 mol year 1 surface biogeochemical processes affect the benthic fluxes of ba2 such that the deep ba2 flux is completely consumed through the precipitation of authigenic barite baso4 in surface sediments the black sea i cycle is likely to be affected by mud volcanism if the 50 known black sea mud volcanoes share the rather sluggish activity of the dmv mud volcano fluxes of li b sr and din instead are too small to affect black sea geochemical cycles on a global scale mud volcanism could play a role in the marine cycles of li b sr i and din if current estimates of mud volcano abundance are correct

when mud volcanoes sleep insight from seep geochemistry at the dashgil mud volcano azerbaijan the worlds 1500 mud volcanoes are normally in a dormant stage due to the short duration of eruptions their dormant stage activity is often characterized by vigorous seepage of water gas and petroleum however the source of the fluids and the fluid rock interactions within the mud volcano conduit remain poorly understood in order to investigate this type of activity we have combined satellite images with fieldwork and extensive sampling of water and gas at seeping gryphons pools and salsa lakes at the dashgil mud volcano in azerbaijan we find that caldera collapse faults and e w oriented faults determine the location of the seeps the seeping gas is dominated by methane 94 9 99 6 with a 13c v pdb in the 43 9 to 40 4 range consistent throughout the 12 analysed seeps ethane and carbon dioxide occur in minor amounts seventeen samples of seeping water show a wide range in solute content and isotopic composition pools and salsa lakes have the highest salinities up to 101 043 ppm cl and the lowest 18o v smow values 1 4 the mud rich gryphons have low salinities 18 000 ppm cl and are enriched in 18o 18o 4 6 the gas geochemistry suggests that the gases migrate to the surface from continuously leaking deep seated reservoirs underneath the mud volcano with minimal oxidation during migration however variations in gas wetness can be ascribed to molecular fractionation during the gas rise in contrast the water shows seasonal variations in isotopic composition and surface evaporation is proposed as a mechanism to explain high water salinities in salsa lakes by contrast gryphons have geochemical signals suggesting a deep seated water source these results demonstrate that the plumbing system of dormant mud volcanoes is continuously recharged from deeper sedimentary reservoirs and that a branched system of conduits exists in the shallow subsurface while the gas composition is consistently similar throughout the crater the large assortment of water present reflects the type of seep i e gryphons versus pools and salsa lakes and their location within the volcano our data highlight the importance of a carefully planned sampling strategy when the target is water geochemistry whereas the methane content and isotopic composition is relatively independent of the particular seep morphology

fluid sediment interactions at eastern mediterranean mud volcanoes a stable isotope study from odp leg 160 abstract pore fluids from two odp sites at eastern mediterranean mud volcanoes have been analyzed for their cl concentration and their 18o and d isotopic composition the cl data span a wide range of concentrations from extremely depleted with respect to seawater as low as 60 mm at the crest of milano dome site 970 to strongly enriched up to 5 4 m at napoli dome site 971 chloride enrichment is known to be due to dissolving messinian evaporites whereas the source of the low cl fluid is deduced from stable isotope data presented here the isotopic composition of the endmember fluid is found to be 10 for 18o and 32 for d for low as well as for high cl waters from this signature it can be concluded that neither gas hydrates nor meteoric water play a significant role in the freshening of the pore water several other processes altering the 18o d composition of pore waters are discussed and considered to be of only negligible influence the process characterizing the isotopic composition of the fluid is found to be clay mineral dehydration mainly smectite illite transformation corresponding to a depth range of 3 5 7 km and an elevated temperature of about 120 165 c a quantitative estimate shows that this reaction is capable of producing the observed extreme cl depletion

sources of solutes and heat in low enthalpy mineral waters and their relation to tectonic setting new zealand abstract approximately 90 of the low enthalpy spring systems in new zealand are distributed along the present day convergence of the pacific and australian plates which varies from subduction to oblique plate collision forearc subducted waters rising in the hikurangi accretionary prism consist of pore waters containing labile organic material water of hydration from clays and seawater these subducted waters are traceable in the north island axial ranges and the northern marlborough fault system in the south island albeit modified by temperature mixing with surface and heated meteoric waters and protracted interaction with the rock the signature of subducted marine sediments in the hikurangi trench is retained in the chemical and isotopic compositions of the taupo volcanic zone magmatic arc type waters the concentrations of b ba br ca cl i k li mg na rb and sr solutes found in high concentrations in forearc subducted waters increase from northeast to southwest towards the incipient subduction zone in the puysegur trench southwest of south island most thermal mineral waters in the south island are expelled along the alpine fault zone where plate collision results to rapid uplift of the southern alps elevated geothermal gradients and fault shearing of rocks in the alpine fault zone variations in temperatures 175 30 c and mineral water compositions are affected by elevation hydrological gradient intensity of tectonic activity permeability fluid volume and rate of throughput and rates of uplift as the main trace of the alpine fault zone is approached concentrations of cl and other solutes generally increase suggesting increasing contributions from ascending cl rich metamorphic waters outside the active convergent zone low enthalpy springs discharge diagenetically modified ancient forearc waters na cl sedimentary formation waters and heated seawater na hco 3 cl waters and na hco 3 deep circulating heated meteoric waters the total surface heat flow in the north island low enthalpy mineral waters is more than 10 higher than in the south island with projected subsurface temperatures as high as 250 c this is because of the widespread occurrence of shallow magmatic and mantle sources associated with pliocene to holocene volcanism and back arc continental rifting the sources of heat and solutes in low enthalpy mineral waters outside the taupo volcanic zone and ngawha are decoupled except for rapidly ascending hot pore waters in the hikurangi accretionary prism and low temperature serpentinization ca cl waters in fiordland

shelf open ocean exchange forced by wind jets abstractthe general problem of exchange from a shallow shelf across sharp topography to the deep ocean forced by narrow cross shelf wind jets is studied using quasigeostrophic theory and an idealized primitive equation numerical model interest is motivated by katabatic winds that emanate from narrow fjords in southeast greenland although similar topographically constrained wind jets are found throughout the world s oceans because there is no net vorticity input by the wind the circulation is largely confined to the region near the forcing circulation over the shelf is limited by bottom friction for weakly stratified flows but stratification allows for much stronger upper layer flows that are regulated by weak coupling to the lower layer over the sloping topography the topographic beta effect limits the deep flow while for sufficient stratification the upper layer flow can cross the topography to connect the shelf to the open ocean this can be an effective transport mechanism even for short s

boron isotopes in different grain size fractions exploring past and present water rock interactions from two soil profiles strengbach vosges mountains abstract in the present study we test the ability of b isotopes to trace past and present weathering reactions in the case of two forest soils formed by a polyphasic sequence involving early hydrothermal alteration of the bedrock and pedogenesis we provide b chemical and isotopic compositions in two 2 m soil profiles sampled in the strengbach watershed vosges france the two soils belong to different soil series an ochreous podzol haplorthod and a brown acidic soil dystrochrept developed on the same granitic bedrock but differently affected by hydrothermal alteration separated granulometric fractions and bulk soil samples have been analyzed coarse particles are mostly composed of primary minerals and show a clear anti correlation between 11 b and mg al reflecting various grades of the early hydrothermal alteration the finest particles clay size fractions deviate from this hydrothermal trend and are diagnostic of pedogenic processes occurring after b exchange with the surrounding 11 b rich soil solution examination of the b distribution in different particle size fractions also indicates that b is transferred from the coarse sand fraction in deeper soil layers to the clay fraction in the upper layers the intermediate size fractions are found to play only a secondary role in the soil forming reactions the two soils show distinct b isotope profiles which are consistent with the different pedogenic processes that govern their formation in the podzolic soil 11 b can be explained by a simple model in which pedogenesis occurs by continuous dissolution of primary minerals and precipitation of secondary ones in the brown acid soil a more complex model that includes the precipitation of clay minerals in the deep horizon and their gradual dissolution in the upper soil layers accounts for the observed results additionally residual hydrothermal illites are more resistant to weathering and are found in the clay fraction where they were directly inherited from the dislocation of coarser grains in which they were encapsulated on a broader scale the large b isotopic fractionation during water rock interactions greatly facilitates the quantification of matter exchange between soil solutions and solids and the determination of global weathering rates the data from the present study demonstrate that the determination of b isotopes in different particle size fractions can reveal the relative importance of source and process effects during weathering

significance of mud volcanism 1 mud volcanism and diapirism have puzzled geoscientists for 2 centuries they have been described onshore and offshore in many places on earth and although they occur in various tectonic settings the majority of the features known to date are located in compressional tectonic scenarios this paper summarizes the main thrusts in mud volcano research as well as the various regions in which mud volcanism has been described mud volcanoes show variable geometry up to tens of kilometers in diameter and several hundred meters in height and a great diversity regarding the origin of the fluid and solid phases gas predominantly methane water and mud may be mobilized at subbottom depth of only a few meters but in places can originate from several kilometers depth with minor crustal or mantle input the possible contribution of mud extrusion to global budgets both from quiescent fluid emission and from the extrusive processes themselves is important in regions where mud volcanoes are abundant such as the collision zones between africa and eurasia fluid flux through mud extrusion exceeds the compaction driven pore fluid expulsion of the accretionary wedge also quiescent degassing of mud volcanoes may contribute significantly to volatile budgets and hence to greenhouse climate

trinidad mud volcanoes where do the expelled fluids come from abstract in order to establish the origin of fluids expelled from mud volcanoes in trinidad we analyzed their major element trace element and isotopic h o sr compositions the mineralogical chemical and sr isotope compositions of associated expelled muds were also determined on the basis of their chemical and sr isotope compositions the fluids were divided into two groups those southwest and northeast of a major right lateral wrench fault the los bajos fault that both controls the chemical quality of the fluids and acts as a drain strontium isotopes were derived via mixing between a radiogenic source 0 71135 and a nonradiogenic source 0 70671 for both southwest and northeast groups however the nonradiogenic source possibly feeding the northeast group showed a lower sr concentration than that of the southwest group h and o isotope data show that the fluids became enriched in 18 o through interaction with wall rocks the fluids were originally oceanic but their properties were subsequently modified by diagenesis as evidenced by chemical data and mixing between fluids issued from two deep seated reservoirs and surface aquifer end members the gas phase expelled with the mud and the fluid through the mud volcanoes is composed mainly of methane with minor carbon dioxide the amount of expelled gas seems the same in samples from both sides of the los bajos fault the almost unique methane content of the gas phase and the large positive 18 o shifts of the reservoir end member as well as b li and ba contents reveal that the fluids from the deep seated reservoirs inherited their chemical compositions at high temperature fluid rock interactions estimates of equilibrium temperatures of the two deep seated reservoirs suggest that to acquire the estimated higher temperature 150 c the mud volcanoes must have been fed partly by a reservoir located at a depth of more than 3 km this depth corresponds to previous geologic information which located the deep seated reservoir in miocene sediments at such a comparable depth the mixing of the original fluids with a less deep seated reservoir and meteoric waters on the ascending path suggests the presence of a recharge mechanism and contributes to the dynamics of the expulsion itself

winter eddy genesis in the eastern south china sea due to orographic wind jets abstract generation of mesoscale eddies in the eastern south china sea scs in winters during august 1999 to july 2002 is studied with a reduced gravity model it is found that the orographic wind jets associated with the northeast winter monsoon and the gaps in the mountainous island chain along the eastern boundary of the scs can spin up cyclonic and anticyclonic eddies over the scs results suggest that direct wind forcing could be an important generation mechanism for the rich eddy activity in the scs and that to simulate this mechanism the resolution of the wind forcing has to be high enough to resolve the local wind jets induced by orographic effects

mineralogy and sedimentology of the miocene gocenoluk borate deposit kirka district western anatolia turkey the miocene boratiferous district of kirka in western anatolia turkey is the most important na borate borax resource in the world two separate deposits in the kirka district are located near the villages of sarikaya and gocenoluk eskisehir province borax is intensively exploited in open pit mines in the sarikaya deposit while only small quarries of colemanite are known in the gocenoluk deposit recent exploratory drilling in the gocenoluk area intersected a thick succession of dolostones tuffs and three borate bearing units lower intermediate and upper borate units in them the most abundant borate mineral is ulexite ca na borate passing at depth to probertite borax na borate is only present in the intermediate borate unit minor amounts of colemanite ca borate and hydroboracite ca mg borate occur at the base and or top of each mineralized unit pyroclastic layers within the borate units show intense alteration by alkaline boron bearing waters and formation of diagenetic clay minerals smectites zeolites analcime and borosilicates searlesite the gocenoluk succession is interpreted as a shallow ephemeral alkaline lake deposit in which carbonates formed as stromatolites and travertines borate precipitation in the gocenoluk area took place interstitially within muddy and carbonate sediments in a lateral progression from marginal ca borates towards na ca borates and rarely to na borates in the center of the lake authigenic silicate mineral distribution shows parallel changes toward the center of the lake that reflect increasing ph gradient

unraveling complex 2 μm clay mineralogy from soils using x ray diffraction profile modeling on particle size sub fractions implications for soil pedogenesis and reactivity a specific methodology was developed to refine the complex clay mineralogy commonly encountered in soil environments the soil examined was a cambisol developed into a ferralitic paleosol the sample was split into four sub fractions of different particle sizes 0 05 0 05 0 1 0 1 0 2 and 0 2 2 mu m and their respective mass contributions to the overall 2 mu m clay fraction were determined for each sub fraction x ray diffraction xrd patterns were modeled using a trial and error approach based on the direct comparison of experimental and calculated profiles quantitative information derived from the fitting procedure for the different sub fractions allowed for the determination of the complex mineralogy of the 2 mu m clay fraction through the identification and quantification of eight clay phases the results show that the finest and most reactive clay fraction 0 05 pm was totally hidden in the xrd pattern of the 2 mu m fraction the fraction commonly considered in soil mineralogical analyses similarly this procedure revealed the presence of illite smectite chlorite and kaolinite illite mixed layer minerals seldom described in soil literature using classical methods the use of this methodology improved our understanding of the pedogenesis of this soil through the identification and quantification of clay phases structural properties the analysis of the evolution of structural parameters with particle size allowed for the detection of local modifications in the interlayer composition of expandable and hydroxy interlayered vermiculite layers following this approach key information can be derived to determine subtle changes in clay mineralogical composition that are related to microorganism and or plant activity

geochemistry of mineral waters and associated gases of the sakhalin island far east of russia abstract isotopic and chemical data on the mineral water mud volcanoes fluid and associated gases from the biggest russian island sakhalin together with previous stable isotope data d 18 o dd 13 c allow elucidation of their origin and general evolution the water fluid circulation is mainly related to marine environment inducing three distinct types na hco 3 cl alkali carbonate groundwaters na cl hco 3 highly evolved saline and na cl mature groundwaters indicating different evolution chemical evolution of groundwater on sakhalin island demonstrated cation exchange and salinization as dominant evolutionary pathways isotopic composition of groundwaters varies from meteoric to metamorphic waters these metamorphic waters consist of water hydration from the clay and seawater are traced in fluids of yuzhno sakhalin mud volcano despite modification by mixing with meteoric waters and water rock interaction processes fault systems that define the areas of highly mineralized water circulation appear to play a major role in the co 2 migration to the surface and ch 4 generation the 13 c co 2 values have pointed that gas phase in high pco 2 waters mostly consists of mantle derived co 2 the carbon isotope signature of methane 13 c ch 4 and d ch 4 indicates its distinct origin which is specified by tectonics methane manifestation in the south of the sakhalin island is mainly related to thermogenic reservoirs as they are more often dislocate by tectonics and crossed by active and permeable faults the sources of biogenous methane in the north of sakhalin island is related to younger and shallower reservoirs and less affected by tectonic processes the determinations of 222 rn have allowed observing that maximal radon flux is associated with high pco 2 waters

new insights into fluid rock interaction mechanisms at mud volcanoes implications for fluid origin and mud provenance at bahar and zenbil azerbaijan abstract understanding the fluid rock interactions occurring in terrestrial mud volcanoes is a premise for elucidating the bio geochemical processes involved in the release of aqueous fluids mud and gases to the earth s surface and atmosphere for the first time fluid and mud ejecta from the mud volcanoes at bahar and zenbil located in eastern azerbaijan and in the shallow coastal water of the south caspian were collected and analyzed for their mineralogical textural and chemical composition the expelled aqueous fluids have a na cl hco3 composition and are generated by the mixing of evaporitic caspian seawater and ancient low to high salinity sedimentary pore water at temperatures of 32 3 c and 42 5 c for the mud volcanoes at bahar and zenbil consistent with mud chambers to be situated in the pliocene sediments at 2 3 km depth these aqueous fluids are strongly enriched in major solutes like na cl hco3 b br nh4 and doc as well as in some trace elements as ba cu fe li sr and zn with concentrations up to 220 times that of the current caspian seawater this chemical concentration is caused mainly by a combination of i strong surface evaporation ion exchange and adsorption desorption involving smectite clays redox driven reactions and carbonate mineral precipitation at relatively shallow depths not deeper than 4 km as well as ii thermal breakdown of organic matter and methane production in deeply buried 4 to 7 km depth organic rich strata biogenic processes are only of minor importance the mud is sourced from all horizons the mud volcanoes are cross cutting partly altered by diagenetic processes alteration is comprised of illitization of smectite during burial diagenesis 120 to 150 c replacements of feldspar by kaolinite and smectite weathering of sulfide minerals fe oxy hydroxide formation as well as oxidation of methane and organic matter in the near sub surface environments at low temperature

deep petroleum occurrences in the lower kura depression south caspian basin azerbaijan an organic geochemical and basin modeling study abstract high sedimentation rates as much as 2500 m ma during pliocene pleistocene with a resultant undercompacted section as thick as 10 000 m and lower than normal geothermal gradients are the main characteristics which have created all the means for generation and preservation of oil at deep layers in the lower kura depression oils collected from eight different oil fields for analyses seem to have originated from a common source rock which probably is clastic deposited in relatively subanoxic to suboxic transitional marine environment receiving low to moderate input of terrestrial organic matter oils from shallow a computer aided basin modeling study has been carried out to outline the spatial variation of the oil window and thus help in further identification of possible source rocks for the reservoired oil in the lower kura depression results suggest that the potential hydrocarbon source horizons of the miocene and pliocene red bed series of the so called productive succession are even at depocenter areas immature with respect to oil generation and thus are very unlikely to have been source rocks for the reservoired oils however the oligocene lower miocene maykop rocks are marginally mature to mature depending on locality and the eocene and older rocks are mature with respect to oil generation at all representative field locations oil generation commenced at the end of pliocene and continues at present at depths between 6000 and 12 000 m an unusually deep 10 000 m oil window in the depocenter areas has been caused by the depressed isotherms due to extremely high sedimentation rates up to 3000 m ma for the last two million years the main phase of oil generation is taking place at depths greater than what most of the wells in the study are have reached

geochemistry and mineralogy of rare earth elements in high phosphorus ooidal ironstones a case study of the kamysh burun deposit azov black sea iron province abstract this study is aimed at characterizing the distribution and speciation of the rare earth elements and yttrium ree y in ooidal ironstones from the kamysh burun deposit kerch peninsula with implications for the depositional environments and contributions of different ree y carriers to the ore budget the lower pliocene ooidal ironstone sequence of the so called kerch ores up to 15 m thick occupies an area of 28 km2 the ore sequence lies between miocene lower pliocene shell limestones and upper pliocene pleistocene sandy and clayey sediments and consists of horizontal ooidal ironstone beds composed mainly of goethite and x ray amorphous fe3 oxy hydroxides intercalated with siderite and or rhodochrosite beds iron is a main component in ooidal ironstones 50 03 66 19 wt fe2o3 and 1 61 wt feo as well as in fresh carbonate ores 34 wt feo and 14 70 wt fe2o3 the kerch ores contain up to 4 59 wt p2o5 and show significant positive correlation between p and fe r 0 75 the bulk ore samples and their coarse 1 10 mm fractions are goethite dominated and have similar phase major and trace element and ree compositions the fine la nd ca pr sm the ree content in fresh carbonate ores is below that in paas xav 103 ppm but approaches the latter in oxidized crusts xav 178 ppm the kerch ironstones also contain ree poor early diagenetic fe2 phosphate vivianite ree xav 0 93 ppm and ca fe2 phosphate anapaite ree xav 6 95 ppm with typical seawater ree y distributions the ooidal ironstones show mree enriched patterns with distinct negative y anomalies which reveals fe3 oxy hydroxides as chief carriers of adsorbed ree mainly mree the kerch ironstones accumulated ree progressively due to hysteretic dissolution and precipitation of fe3 oxy hydroxides in oscillating redox conditions the diagenetic source of ree stored in ooidal goethite ironstones was inferred from the paas normalized values cen cen vs nd and cen cen vs yn hon discrimination diagrams in general the ree y budget of the kerch ooidal ironstones mainly formed during early diagenesis and scavenging from pore water with a minor contribution of siliciclastic inputs in the absence of hydrothermalism

how many boron minerals occur in earth s upper crust the current rate of discovery of new boron minerals 65 species or potential species described from 2008 to 2017 is higher than at any prior 10 year period implying that rates of b mineral discovery could increase further with no obvious limit to boron mineral diversity in earth s crust in contrast large number of rare events lnre models calculated from the 295 species of b minerals discovered through 2017 give a total predicted b mineral endowment in earth s crust of 459 65 5 and 523 species using a finite zipf mandelbrot fzm model and sichel s generalized inverse gauss poisson model gigp respectively i e there is a very real predicted limit of no more than 500 species as cautioned by hazen hystad and their co authors lnre modeling presumes no changes in how minerals are discovered from the beginning of mineral discoveries in the late 18th century to early 2017 however this condition is clearly not the case and thus changes could explain the discrepant indications the most important changes are 1 the advent of the electron microprobe which became widely used for chemical analysis of b minerals in 1978 2 technological advances in single crystal x ray diffractrometry 3 technological advances in electron microscopy including advent of electron backscattered diffraction 4 advent of micro raman spectroscopy and 5 changes in mineralogical nomenclatures particularly of the tourmaline supergroup changes 1 to 4 are expected to reduce the size of the mineral grains that can be studied thereby increasing the number of species accessible to study furthermore should species have a fractal distribution i e diversity is independent of scale examination of increasingly smaller grains will turn up an even larger number of species to evaluate the impact of these changes on the lnre modeling we modeled the 146 b minerals discovered up through 1978 which was selected as the cutoff because of 1 the important role played subsequently by the electron microprobe and 2 the number of species was 50 of the current number this modeling gave 306 fzm and 359 gigp for total species i e the access to smaller grains afforded by advanced analytical instrumentation has resulted in an increased estimate of total endowment by 50 from 1978 whether the fzm or gigp distribution is applied we doubt that the 500 b species estimate is the end of the story as we expect there will be further technological advances in the future a more realistic finale might come when we reach the natural limit imposed by the minimum number of unit cells needed for new mineral to be viable and thus lnre modeling might yet show that earth s total endowment of b minerals is finite a review of past patterns of discovery of new boron minerals which can inform us what to expect in future discoveries reveal that only 19 of b minerals were synthesized prior to discovery we conclude that synthetic compounds are not a particularly promising source of potential new b minerals in contrast 22 of b minerals were discovered prior to synthesis and 29 have unique structures i e they have no synthetic analogs and are not isostructural with a known mineral accordingly 41 of b minerals could not be predicted and we conclude that the realm of as yet undiscovered b minerals holds a significant number of surprises

the geochemistry and origin of the hydrothermal water erupted at lusi indonesia abstract the spectacular lusi mud eruption started in northeast java the 29th of may 2006 despite extensive research the origin of the erupted water remains elusive and poorly constrained here we present a comprehensive study of the geochemistry of lusi waters compared with those collected from surrounding areas all collected between 2006 and 2013 including data from mud volcanoes and volcano hosted hydrothermal springs within this broad context the geochemical characteristics of the fluids expelled in the lusi region suggest that we can classify the waters in three groups 1 meteoric waters expelled in cold springs and artesian wells 2 hydrothermal waters typically mixed with meteoric waters and 3 formation water from marine sediments altered by diagenetic processes such as clay mineral dehydration samples collected from the lusi crater are cl and na dominated up to 527 mm and 471 7 mm respectively similar to seawater indicating that altered sedimentary formation waters are predominant in this system in addition they are enriched in sr up to 808 4 m and other elements commonly associated with hydrothermal systems such as li up to 877 6 m compared to 26 m in seawater some of these elements are up to ten times enriched compared to seawater values high temperature fluid mineral interactions in the subsurface appear to have facilitated the transfer of li and other mobile elements into the fluids high temperature fluid mineral interaction reactions are also supported by si concentrations significantly higher compared to other sampled mud volcanoes in the island crater samples also show the highest 18o values 5 after correction for evaporation compared to 1 at the mv localities 87sr 86sr ratios vary between of 0 7077 and 0 7083 and seem to reflect a general mixture of fluids from clay mineral dehydration carbonate recrystallization alteration of volcanic rocks and hydrothermal imprint eight years of geochemical monitoring indicate that the composition of the deep sourced lusi fluids remain fairly constant through time thus our findings show that the lusi crater waters represent a regional geochemical anomaly and we suggest that a combination of high temperatures in the source region and fluid rock interactions with silicates and possibly carbonate rich lithologies can explain the data this is consistent with a model where the emitted gases migrate from a deep seated 4 km source region likely associated with the presence of hot igneous intrusions and or high t reactions related to the presence of neighbouring active volcanoes

analysis of deep penetrating radar surveys of west antarctica us itase 2001 1 we collected 1850 km of ground based radio echo sounding res data in west antarctica along the 2001 us leg of the international trans antarctic scientific expedition traverse us itase these data represent the first high resolution measurements of ice thickness and internal stratigraphy for portions of this area that bear on questions about the stability of the west antarctic ice sheet wais internal layers depicting isochrones have been traced continuously for much of the profile length and a date from the byrd deep core is ascribed to one of these isochrones from which we estimate vertical velocities across the traverse route comparison of our ice thickness measurements with bedmap show good agreement in regions where the database is well constrained by data coverage where the bedmap dataset was forced to interpolate differences are as high as 45 of the ice thickness

boron isotope systematics in large rivers implications for the marine boron budget and paleo ph reconstruction over the cenozoic abstract the chemical composition of the oceans and long term climate changes are believed to be linked reconstruction of seawater ph evolution is desirable as ph may be related to atmospheric pco2 and hence to climate evolution boron isotopes in oceanic carbonates have been suggested to be a proxy for oceanic paleo ph reconstruction nevertheless the calculation of paleo ph values over geological periods requires a precise knowledge of the boron isotopic composition of the oceans when calcite precipitated we present the systematics of boron isotopic composition of the world s main rivers we deduce a continental boron flux to the oceans of 38 1010 gb year with a mean isotopic composition of 10 these results lead to a balanced boron budget in the oceans and allow the development of a model for the marine boron secular evolution over the past 100 myr it is shown that the oceanic boron cycle is mainly controlled by the boron continental discharge and the boron uptake from the oceans during low temperature alteration of oceanic crust however the recent important increase of the clastic sediment supply linked to the himalayan erosion impacts the oceanic boron budget by enhancing significantly the boron uptake by adsorption on sediments we predict a boron isotopic composition in the oceans lower during the cenozoic and slightly higher during the cretaceous than today the modelled values for the marine boron isotopes follow the variations of boron isotopes in carbonates over the cenozoic era provided by previous studies suggesting that the variations of the seawater ph may not have been important on this time scale if this is the case it involves that buffering mechanisms occur in the oceans to maintain seawater ph at a roughly constant value against past atmospheric pco2 variations

chemical and isotopic evidence for sources of fluids in a mud volcano field seaward of the barbados accretionary wedge chemical isotopic and heat budgets are controlled by fluid flow and venting at convergent margins fluids vent from accretionary complex sediments via numerous pathways including mud volcanoes which are common at the barbados convergent margin chemical and isotopic compositions of fluids collected from four mud volcanoes located east of the barbados deformation front at 13 50 n indicate venting is sufficiently rapid to prevent diffusion from seawater in sediments surrounding the mud volcanoes the rate of nonfocused fluid flow is 0 26 cm yr although this rate is 3 orders of magnitude slower than the flow from the mud volcanoes significantly more fluid vents from the sediments surrounding the mud volcanoes than from the restricted areas of rapid flow from the volcanoes chloride concentrations are depleted to a minimum of 211 mm 45 of seawater value primarily by mixing diagenetically altered pore fluids with an 18o enriched fresh water released from the dissociation of methane hydrate this reaction is accompanied by the release of sufficient methane to form a free gas phase and initiate eruption of the mud volcanoes the geochemical compositions of the diagenetically altered pore fluids reflect the interplay between five major reactions 1 clay mineral dehydration which releases h2o and influences a range of chemical and isotopic compositions 2 organic matter regeneration which increases alkalinity nh4 and br and decreases so42 concentrations 3 cation exchange with clay minerals which increases na and decreases nh4 concentrations 4 carbonate recrystallization and precipitation which decrease ca2 but increase sr2 concentrations and 5 conversion of volcanic ash to clay minerals which utilizes h2o and decreases mg2 concentrations the geochemistry of the pore fluids suggests that these reactions occurred at temperatures ranging from 75 to 115 c thus at the regional geothermal gradients of 27 to 40 c km these temperatures indicate that the source regions are at 2 to 4 5 km depth

the 2011 strong fire eruption of shikhzarli mud volcano azerbaijan a case study with implications for methane flux estimation shikhzarli is a typical active mud volcano mv in azerbaijan with extremely high percentages of fire eruptions reaching 74 the strong eruption of shikhzarli mv on 13 march 2011 shamakhi gobustan region central azerbaijan at 40 29 12 5 n 49 02 03 4 e was accompanied by gas ignition with a straight flow vertical gas flare a large 60 m height short living 30 min gas flare and small 1 5 m height gas spouts with longer lifetimes 5 h were simulated in sigmaflow and the model was used to evaluate methane flux and the amount of combusted methane geological and mineralogical data field observations as well as eye witness reports and photographs in mass media were used to choose the boundary conditions for the gas fire simulation this study provides the first quantitative evaluation for methane emission during an mv catastrophic eruption as simulation predicts 14 000 m3 of methane was consumed for the life time 30 min of the main 60 m high flare which is equivalent to nine tons of cold gas at ambient conditions the volume of erupted methane for the 5 h lifetime of a small spout 1 5 m high was 72 6 m3 45 kg of cold ch4 the amount of methane emitted during a single strong flame eruption is commensurate with the annual output of permanently active individual mv vents or may be ten to hundred times as high

boron isotope composition of secondary smectite in suevites at the ries crater germany boron fractionation in weathering and hydrothermal processes abstract the 24 km diameter ries crater in germany is one of the best preserved terrestrial complex impact structure and clay minerals in the groundmass of the ries suevites have been recognized for several decades it is generally accepted that these clays were formed by post impact aqueous alteration of impact generated glasses and or finely comminuted crystalline basement material at temperatures above ambient conditions the ries impact structure provides a good opportunity to study the evolution of post impact development of impact craters here we present a study of boron isotopic compositions 11 b and b concentrations of the secondary smectite clay fraction in fall out and crater suevites from the ries crater germany these data were used to study the boron fractionation in clay mineral precipitation processes and to model using b isotope fractionation the characteristics ph temperature and salinity of fluids during fluid rock interaction at different positions within the crater the results of this study show that the boron isotopic composition of smectite in fall out suevites sampled from 4 different locations average 24 5 1 8 was significantly different from that of the smectite in crater suevites sampled from the nordlingen 1973 drill core at different depth intervals from 370 m to 525 m average 4 07 similarly the 11 b composition of the fluids responsible for the alteration calculated from smectite isotopic composition in the fall out suevites 7 5 1 6 differed from the alteration fluid composition in crater suevites 17 6 10 8 indicating a different origin of the fluids responsible for the alteration of the fall out and crater suevites in the ries crater our results suggest that the alteration in fall out suevites occurred at lower temperatures than the crater suevites and at a lower ph which is consistent with the smectite precipitation in equilibrium with meteoritic fluids the boron isotopic composition of smectite in the crater suevites suggests secondary clay formation at higher temperatures and or at elevated ph 8 9 low 11 b values of fixed boron in secondary smectite in fall out suevites suggests that b was incorporated into the mineral structure during the precipitation of authigenic smectite whereas the smectite precipitated in equilibrium with the boron and hydrogen isotopic composition in the meteoric water that percolated through the system our study provides new constraints on the origin and evolution of the geothermal fluids that were involved in the formation of altered minerals at the ries crater and suggests that boron isotope composition studies of the secondary clay phases associated with post impact cooling may have important implications for the changes in fluid flow and changes in geochemical signatures of the fluids and provide new constraints on fluid rock interaction and mass transport during the cooling of the impact crater

mud volcanism and fluid geochemistry in the cheleken peninsula western turkmenistan abstract a geological and geochemical study has been carried out to investigate the relationships between major mud volcano structures and deep fluid migration in the cheleken peninsula in the south caspian basin the fluid geochemistry allowed the origin and migration of the saline waters and the hydrocarbons to be deduced along with the regional source and reservoir rocks the emitted waters formed by the mixing of deep highly saline water from the main source rocks of the maykop fm with the caspian like pore water contained in the pliocene reservoirs the water composition is very similar to that emitted by the mud volcanoes in azerbaijan allowing comparisons to be done between the reservoirs in the western and eastern sides of the south caspian basin the associated oil is derived from a mixed type ii iii kerogen deposited in a sub oxic marine environment and generated during the early oil window the oil biomarkers indicate that the source rock is the maykop fm as previously determined for the other areas of the south caspian basin the spontaneous emissions showing different morphologies are mainly aligned along normal and transtensive fault systems which provide effective pathways for rapid fluid ascent from deep reservoirs to the surface