petedunnite caznsi2o6 stability and phase relations in the system cao zno sio2 the phase relations of petedunnite caznsi2o6 pd were determined experimentally at p t conditions up to 2 5 gpa and 1100 c single phase petedunnite is formed at high pressures p 0 8 gpa reversed experiments show that at lower pressures and temperatures 650 c petedunnite decomposes to willemite zn2sio4 wil hardystonite ca2znsi2o7 har and quartz sio2 qtz according to the reaction 4 pd wil 2 har 3 qtz the boundary curve for this equilibrium reaction is given by p gpa 0 093 0 029 0 0014 0 0003 t c by disregarding the phase transition of quartz the stability field of wil har qtz is restricted toward lower temperatures by zinc feldspar caznsi3o8 zfsp according to the known reaction wil 2 har 7 qtz 4 zfsp these reactions intersect at 650 1 c 0 78 0 01 gpa generating an invariant point i pd additionally petedunnite breakdown reaction is intersected by the low high quartz phase transition curve generating an invariant point i pdqtz at 840 c 1 04 gpa at temperatures 650 c further reactions occur in the system cao zno sio2 including the doubly degenerate reaction zfsp pd qtz and 3 pd har wil zfsp which also intersect the invariant point i pd all reactions involving petedunnite display shallow positive slopes within the p t field indicating that the crystallization of petedunnite is highly pressure sensitive over a wide temperature range this means that an increasing petedunnite component in pyroxene shifts its stability field to higher pressures similar to the effect of a jadeitic component the study of natural clinopyroxene and the correlation of its zinc content with published p t conditions of these mineral assemblages confirmed a significant relationship between extraordinary high zinc concentrations in pyroxene and high metamorphic pressure conditions in addition the petedunnite component is obviously sensitive to the prevailing fluid conditions in terms of the fugacity ratio f s2 f o2 furthermore a distinct temperature dependency of the zinc component was observed in the range of trace element concentration in consequence zn turns out to be a key element with regard to its implementation as a sophisticated petrogenetic indicator of metamorphic conditions therefore routine measurement of zinc in element analyses of clinopyroxenes is strongly recommended

biostratigraphy and sedimentology of the fluviatile untere serie early and middle miocene in the central part of the north alpine foreland basin implications for palaeoenvironment and climate the early to middle miocene fluviatile untere serie lithostratigraphic unit of the upper freshwater molasse ufm in the north alpine foreland basin nafb crops out in a 40 m long section at untereichen altenstadt central part of the nafb this section yields a unique superposition of two vertebrate assemblages belonging to different biostratigraphic units early part osm c d karpatian and osm e early badenian detailed taxonomic analyses reveal different diversity patterns in the two assemblages nine small mammal and six ectothermic vertebrate taxa occur in the older level ua 540 m while 20 small mammal and 23 ectothermic vertebrate taxa are recorded for the younger level ua 565 m from the latter locality comes a small sized representative of the biostratigraphically significant megacricetodon lappi lineage this evolutionary level has not been documented previously for the eastern part of the nafb bioclimatic analysis combined with lithofacies and architectural element analysis indicates that significant changes in the fluvial sedimentation style surface water runoff and tectonics occurred between the early karpatian and early badenian a meandering fluvial system marly unit is erosively overlain by sandy braided river deposits sandy unit overbank deposits of the marly unit revealed that the older vertebrate fossil assemblage ua 540 m is deposited in an animal burrow that was presumably produced by owls both reptilian and mammalian taxa are indicative of a relatively open environment and dry probably semi arid climate conversely vertebrates from the sandy unit ua 565 m which are accumulated in channel fill deposits suggest closed as well as open habitats with a subtropical humid climate and mean annual rainfall of about 1 000 mm according to the sequence stratigraphic analysis the marly unit is interpreted as a highstand system tract of the tb 2 2 global 3rd order sequence the new results add support to the hypothesis that the erosional unconformity between both sedimentary units spanning the karpatian badenian transition corresponds to the pre riesian hiatus which has been interpreted as part of the styrian tectonic phase and was previously identified only in the eastern and northeastern part of the nafb the biostratigraphic data further indicate that this hiatus lasted longer in the eastern than in the central part of the basin

rapid analytical method for trace zn contents in some mafic minerals using the electron microprobe potential utility as a metallogenetic and petrogenetic indicator abstract an analytical method using an electron probe microanalyser epma has been developed to enable rapid determination of trace zn contents in mafic silicates total matrix correction factors of atomic number absorption and fluorescence zaf correction factors for zn are constant and virtually independent of solid solution composition and mineralogy zn analysis confirmed by inductively coupled plasma optical emission spectrometry icp oes reveals that this epma method is capable of analyzing zn within only 30 s at a detection limit of 50 ppm preliminary studies of zn abundance indicate that 1 clinopyroxenes in skarn deposits tend to vary their zn contents in accordance with the metal type 500 ppm for the w type 2 zn contents of granitic biotites in the ishikawa area northeastern japan increase from 290 to 610 ppm with the advance of crystallization and 3 zn contents of chlorite in weathered granitic rocks are almost equivalent to those of its primary biotite therefore this rapid epma method may have considerable potential for the use of trace zn as a metallogenetic indicator and as a marker for crystallization or alteration processes

subsurface lateral flow generation in aspen and conifer dominated hillslopes of a first order catchment in northern utah mountain headwater catchments in the semi arid intermountain west are important sources of surface water because these high elevations receive more precipitation than neighboring lowlands this study examined subsurface runoff in two hillslopes one aspen dominated the other conifer dominated adjacent to a first order stream in snow driven northern utah snow accumulation soil moisture trenchflow and streamflow were examined in hillslopes and their adjacent stream snow water equivalents swes were greater under aspen stands compared to conifer the difference increasing with higher annual precipitation semi variograms of shallow spatial soil moisture patterns and transects of continuous soil moisture showed no increase in soil moisture downslope suggesting the absence of subsurface flow in shallow 12 cm soil layers of either vegetation type however a clear threshold relationship between soil moisture and streamflow indicated hillslope stream connectivity deeper within the soil profile subsurface flow was detected at 50 cm depth which was sustained for longer in the conifer hillslope soil profiles under the two vegetation types varied with deep aspen soils having greater water storage capacity than shallow rocky conifer soils though swes were less under the conifers the soil profile had less water storage capacity and produced more subsurface lateral flow during the spring snowmelt copyright 2010 john wiley sons ltd

messinian lago mare deposits near the strait of gibraltar malaga basin s spain a new stratigraphic unit named lm unit located at the base of the pliocene marine succession in the eastern sector of the malaga basin has been distinguished this unit is composed of two fining upward sequences bounded by a discontinuity related to synsedimentary tectonic activity both sequences are made up of basal alluvial deposits overlain by subaquatic deposits the lower sequence contains rich mollusc faunas characterized by bivalves lymnocardiinae and dreissenidae of paratethyan origin and non marine gastropods typical of oligo low mesohaline shallow waters and low diversified ostracod faunas of paratethyan origin loxocorniculina djafarovi tyrrhenocythere pontica euxinocythere maeotocythere praebaquana and amnicythere propinqua typical of low mesohaline waters alternances of monospecific ostracod assemblages made of cyprideis agrigentina or oligotypic assemblages made of c agrigentina and loxoconcha spp and richer assemblages made of l djafarovi accompanied by several amnicythere spp and camptocypria sp 1 characterize the upper sequence pointing to more unstable environment affected by salinity and depth changes some samples collected from this upper sequence yielded rare planktonic and benthic foraminifera which could suggest the sporadic establishment of quasi normal marine conditions in the westernmost mediterranean during the deposition of this sequence the palaeontological data and the palaeomagnetic results obtained in both the lm unit and the overlying pliocene marine sediments restrict the age of the former to the post evaporitic late messinian the age and the environmental conditions correlate these deposits with the lago mare event occurring throughout the mediterranean before the quick and widespread marine flooding of the mediterranean at the beginning of the pliocene

scheelite malayaite and axinite bearing skarns from el hammam central morocco in the el hammam fluorite mining district central morocco 50 km southwest of meknes interlayered pelite and limestone beds have been metamorphosed into banded calc silicate rocks under the influence of a hidden granitic pluton of variscan age various calc silicate bands occur in the following zonal relationship 1 pelitic hornfels quartz muscovite biotite and plagioclase 2 pyroxene feldspar band salitic pyroxene anorthite k feldspar and titanite 3 grossularite band grossularite accessory diopside and idocrase and 4 marble or wollastonite band field relationships suggest that at least part of the calc silicate rocks predated the skarns and were not genetically linked to them mineral assemblages indicatethat the conditions of formation were 525 degrees t 580 degrees c and x sub co 2 0 15 at p total 2 kbars assumed skarns replaced the calc silicate rocks but not the marble beds based on crosscutting and replacement relationships a sequence of three successive skarn formation stages has been recognized scheelite bearing skarns formed during the first stage they occur as unzoned conformable bodies and consist of salite to ferrosalite anorthite scheelite titanite and k feldspar malayaite bearing skarns formed during the second stage they occur conformably to the banding and display different zonal patterns along strike where the replaced calc silicate band is a wollastonite band the succession of zones is zone 1 tin bearing andradite variable tin content up to 1 6 wt sno 2 and wollastonite zone 2 tin bearing andradite variable tin content up to 5 6 sno 2 and malayaite casnsio 5 and zone 3 hedenbergite and malayaite where the replaced rock is a pyroxene feldspar band or a scheelite bearing skarn malayaite bearing skarns consist of hedenbergite and malayaite where the replaced rock is a grossularite band the zonal pattern is disseminated malayaite and disseminated tin bearing andradite and malayaite axinite bearing skarns formed during the third stage as veins and pods in calc silicate rocks and scheelite and malayaite bearing skarns they consist of ferroaxinite and datolite and in places tin bearing manganaxinite up to 1 7 sno 2 wt malayaite bearing skarns formed at t 480 degrees c log f sub o 2 25 and f sub co 2 100 bars assuming p total 2 kbars the temperature was probably higher for scheelite bearing skarns and lower for axinite bearing skarns late alteration of skarns involved partial silicification sulfidation recarbonation and hydration

the direction of fluid flow during contact metamorphism of siliceous carbonate rocks new data for the monzoni and predazzo aureoles northern italy and a global review periclase formed in siliceous dolomitic marbles during contact metamorphism in the monzoni and predazzo aureoles the dolomites northern italy by infiltration of the carbonate rocks by chemically reactive h2o rich fluids at 500 bar and 565 710 c the spatial distribution of periclase and oxygen isotope compositions is consistent with reactive fluid flow that was primarily vertical and upward in both aureoles with time integrated flux 5 000 and 300 mol fluid cm2 rock in the monzoni and predazzo aureoles respectively the new results for monzoni and predazzo are considered along with published studies of 13 other aureoles to draw general conclusions about the direction amount and controls on the geometry of reactive fluid flow during contact metamorphism of siliceous carbonate rocks flow in 12 aureoles was primarily vertically upward with and without a horizontal component directed away from the pluton fluid flow in two of the other three was primarily horizontal directed from the pluton into the aureole the direction of flow in the remaining aureole is uncertain earlier suggestions that fluid flow is often horizontal directed toward the pluton are likely explained by an erroneous assumption that widespread coexisting mineral reactants and products represent arrested prograde decarbonation reactions with the exception of three samples from one aureole time integrated fluid flux was in the range 102 104 mol cm2 both the amount and direction of fluid flow are consistent with hydrodynamic models of contact metamorphism the orientation of bedding and lithologic contacts appears to be the principal control over whether fluid flow was either primarily vertical or horizontal other pre metamorphic structures including dikes faults fold hinges and fracture zones served to channel fluid flow as well

late miocene to pliocene palaeogeography of the paratethys and its relation to the mediterranean abstract the palaeogeographic evolution of the paratethyan and mediterranean realms are reconstructed with three maps ranging from the late miocene to the middle late pliocene the maps are based on the facial analysis of selected deposits clastic input slope slide process analyses as well as biogeographic data of the planktic benthic and terrestrial biota characteristic fossil assemblages are used for palaeobathymetric and palaeohydrologic interpretations restoration of palaeogeographic connections the palaeogeographic reconstructions are palinspastically restored after dercourt j ricou l e vrielynck b eds 1993 atlas tethys palaeoenvironmental maps gauthier villars paris pp 1 307 14 maps the paleogeographic atlas of northern eurasia 1997 inst tectonics lithospheric plates moscow 26 maps with modifications maps have been prepared for the terminal tortonian early messinian late pannonian early maeotian late messinian pontian salinity crisis time and piacenzian gelasian akchagilian they illustrate the neogene palaeogeographic evolution during and after the attic orogenesis though the emerging mountain system of the alpine foldbelt increasingly separated the paratethys from the mediterranean tethys paratethys connections remained extant and sufficiently effective for limited communication between both basins they governed many features of the cyclic depositional history and biogeographic evolution of the eastern paratethys

aspects of freshwater mollusc ecological biogeography abstract freshwater molluscs include a variety of groups derived independently from marine ancestry and varying in range of habitat reproduction and distribution the fossil record shows the great age of most families that likely differentiated in the paleozoic present day distributions of species and higher groups are rationalized as due to different ranges of habitat life history and means of dispersion with a strong historical component at the global level distribution of 42 principal families of freshwater and marginally marine molluscs is summarized most are widespread the others representing only a few types of distributiion groups characteristic of the southern continents tethyan or localized localized families are mostly prosobranchs and are concentrated in areas otherwise noted for endemism the atlantic and indo pacific oceans have vastly different relationss to the ranges of freshwater molluscs the atlantic cuts across genera and sets of genera as if it came into being after the evolution of those groups the pacific is not so crossed but bordered with primitive and local families as if development of the pacific basin were earlier and accompanied origin of living families of pulmonates the fossil record in north america is reviewed briefly already in the cretaceous a faunistic division is recognizable some groups in the west are related to those of east asia others in the east are of trans atlantic relationships withdrawal of the epeiric sea from the mid continent exposed what can be viewed as an enormous land bridge linking different faunistic regions these regions retain distinctiveness today no large scale faunal migrations have occurred supposed migrations to south american and australia are therefore dismissed freshwater mussels have often been employed in zoogeographic studies the region west of the rocky mountains in north america has a sparse fauna of asiatic affinities throughout all of cenozoic time these features have been characteristic emphasizing the hisorical value of mussel distribution the historical roots of some zoogeographic thoughts are traced back to charles lyell who introduced uniformitarianism in geology the principle that the distribution of different groups of freshwater molluscs is carried out in different ways determined by range of habitat and life history is uniformitarian it is based on the action of presently observable processes and on their result over long periods of time attention to details of modern ranges and recognition of polytypic and vicariant groups is in full keeping with lyell s urging patiently to explore the realities of the present lyell s belief in a center of origin of species captivated the mind of charles darwin believing in evolution he nevertheless was compelled to deal with geographic distribution in a lyellian non evolutionary way efforts to deal with animal geography by numbers of immigrants flying birds moving plates and floating rafts go back beyond darwin to lyell s special creation the uniformitarian interpretation of geographic distribution is linked causally to the uniformitarian approach of geology both are corollaries of a more general principle earth and life evolve together this also provides the premises for interpretations of the past

flow and solute transport through the soil matrix and macropores of a hillslope segment subsurface flow from various portions of a soil profile on a steep forested hillslope was evaluated by two sets of step change miscible displacement tests at different application rates and antecedent hydrologic conditions solutions of nacl 1000 mg l 1 cl were applied at steady state rates equivalent to 20 and 30 mm h 1 of standing water over the entire plot area using a line irrigation source located 1 5 m upslope lateral distance from an excavated soil pit subsurface flow and tracer breakthrough from five portions the organic rich soil layer including macropores the mineral soil matrix and three groups of macropores in the mineral soil layer of the soil profile were individually measured and analyzed using a convective dispersive model matrix flow dominated discharge from the soil pit during tracer tests 70 93 of total discharge however during wet periods with upslope drainage macropores including organic rich soil contributed proportionally more flow than during periods when upslope drainage was minimal outflow from macropores during the test with wet antecedent conditions had lower cl concentrations than drainage from the soil matrix suggesting dilution in macropores from upslope drainage effective pore volumes calculated for the flow averaged breakthrough data from the entire profile were much less 40 than the estimates measured by tensiometers of total volume of pore water suggesting that preferential flow significantly contributed to subsurface transport of tracer the pore volume for the entire profile increased only slightly with increasing application rate however the relative proportions of pore volumes calculated for individual portions varied proportionally to antecedent hydrologic conditions these changes are attributed to the expansion of individual macropores with surrounding soil and the lateral extension of macropore networks during wetter conditions

the randeck maar palaeoenvironment and habitat differentiation of a miocene lacustrine system abstract the randeck maar in s germany is a well known fossil lagerstatte with exceptionally preserved fossils particularly insects and plants which thrived in and around the maar lake during the mid miocene climatic optimum late early early middle miocene mammal zone mn5 we provide the first critical and detailed overview of the fauna and flora with lists of 363 previously published partially revised and newly identified taxa plant remains are the most diverse group 168 taxa followed by insects 79 the flora points towards subhumid sclerophyllous forests and mixed mesophytic forests the former being an indication for the occurrence of seasonal drought three main sections can be differentiated for the habitats of the randeck maar lake system 1 deep and open water lake habitats with local and short termed mass occurrences of insect larvae amphibians and or gastropods while fish is particularly scarce the interpretation of the water chemistry is problematic because contradictive palaeoenvironmental indicators for both brackish and freshwater conditions exist 2 shallow parts of the lake comprise a narrow reed belt with insects and gastropods living on the exposed plant stems as well as turtles 3 crater slopes and surrounding plateaus were mainly covered by subhumid sclerophyllous to mixed mesophytic forests depending on sun exposition and soil conditions horses and other forest dwellers preferably lived in forested habitats while proboscideans and rhinoceratids occupied more open habitats our study also brings up contradictive results that cannot be untangled with the current state of knowledge and thus directions for future studies are discussed

stability and phase relations of ca znsi3 o8 a new phase with feldspar structure in the system cao zno sio2 zinc feldspar ca znsi 3 o 8 has been synthesized hydrothermally and its phase relations have been investigated in the system cao zno sio 2 up to pressures of 1 0 gpa single phase zn feldspar grew from an oxide mixture at 600 c and 0 7 gpa within 6 days it crystallizes in space group p 1 displaying lattice constants of a 8 121 1 a b 12 927 1 a c 7 206 1 a 93 76 5 116 120 7 84 368 7 v 675 7 a 3 z 2 heuer et al 1998 in zn feldspar zn and si are ordered on the tetrahedral sites and the structure of zn feldspar is more similar to the low albite structure than to that of anorthite due to the tetrahedral ordering scheme zinc feldspar does not melt congruently but decomposes at subsolidus conditions according to the reaction 4 zn feldspar willemite 2 hardystonite 7 quartz 1 reaction 1 was determined by means of reversed experiments and its negative p t slope can be expressed by the equation p gpa 2 797 0 325 0 0031 0 0004 t c introducing the stability relations of the sio 2 system two invariant points i qtz and i trid are generated at 720 c 0 57 gpa and 896 c 0 016 gpa projected on the low high quartz and high quartz tridymite phase transitions respectively the phase assemblage willemite hardystonite quartz is not stable at pressures above 1 2 gpa where petedunnite is formed according to the reaction willemite 2 hardystonite 3 quartz 4 petedunnite 2 rothkopf and fehr 1998 the stability field of zn feldspar is restricted to pressures 3 o 8 component in addition to ca znsi 3 o 8 we recommend inclusion of zn in analysis of feldspars from such paragenesis

metamorphism of pelites in nkfmash a new petrogenetic grid with implications for the preservation of high pressure mineral assemblages during exhumation a petrogenetic grid for metapelites in the system nkfmash is presented the p t range is investigated in three sections 1 the high and ultrahigh pressure range is discussed in the system nfmash because phengite is the only stable potassic phase 2 the transition region is characterised by four nkfmash invariant points that separate high pressure glaucophane bearing from medium pressure biotite bearing metapelites 3 the medium pressure range contains the fifth nkfmash invariant point the univariant reactions of this point terminate the stability range of paragonite which breaks down to form staurolite or kyanite and plagioclase during decompression and or heating as the growth of albitic plagioclase by decomposition of paragonite via continuous reactions may be conspicuous already before these staurolite or kyanite producing reactions are reached such albite porphyroblast schists are typical indicators of a former high pressure metamorphic history considering the preservation of high pressure metapelitic assemblages those crossing the nkfmash transition region during exhumation commonly dehydrate and preservation is unlikely three types of metapelites have a fairly good survival potential 1 low temperature metapelites up to c 540 c with an exhumation path back into the chlorite albite stability field 2 assemblages with chloritoid glaucophane and 3 the relatively high temperature glaucophane kyanite and jadeite kyanite bearing parageneses that are relatively dry at the onset of exhumation a comparison with data from the literature shows that these rock types are the most abundant in nature

exploring the interplay between infiltration dynamics and critical zone structures with multiscale geophysical imaging a review abstract infiltration is the process of water entering into and routings through the subsurface it has a profound impact on water flux in the earth s critical zone cz influencing phenomena such as overland flow stream generation plant available water and groundwater recharge as well as the associated cz processes and functions of weathering erosion slope stability and food production however reliable measurement of infiltration in structured geomedia soils and regolith with hidden subsurface features remain challenging the increasing availability of geophysical techniques has helped them emerge as viable options for minimally invasive determination of infiltration at the pedon to hillslope or catchment scales geophysical methods replace the educated guesswork of interpreting field data from traditional infiltrometers with direct visualization and quantification this paper provides a comprehensive literature review of various applications of geophysical techniques used to 1 visualize infiltration relevant structures 2 monitor non uniform or preferential infiltration patterns and 3 map soil moisture distribution after infiltration it then proposes a new conceptualization form and function dualism for subsurface hydrology to link preferential infiltration to cz structures with the goal of formulating more realistic infiltration theories related to subsurface structural heterogeneity the characterization of both subsurface structures form and infiltration dynamics function via geophysical imaging should help infiltration models currently emphasizing macroscale behaviors rooted in the continuum concept expand to accommodate the microscale nature of preferential flow integrating multiple geophysical approaches and developments into the new generation of geophysical techniques will further enhance our ability to see into the fabric of the subsurface and capture the dynamics of non uniform infiltration through the hidden half of the cz this approach offers exciting opportunities for understanding the complex interactions between cz structures and cz processes

subsurface runoff characteristics from a forest hillslope soil profile including macropores hitachi ohta japan subsurface flow within forest hillslopes is not well understood a soil pit containing macropores was prepared and instrumented for subsurface flow measurements at the hitachi ohta experimental watershed the subsurface flow from the soil profile was divided into five groups the porous including macropores organic rich soil layer three macropore groups in the mineral soil layer and the mineral soil matrix excluding visible macropores the outflow from the organic rich soil layer coincided with rainfall and depended strongly on rainfall intensity such a response is related to the location of the organic rich layer in the uppermost portion of the soil profile one macropore in the mineral soil was connected directly to a hydraulically active fracture in the bedrock therefore the flow from this macropore group was high and delayed relative to rainfall even though the group is located in the upper left portion of the mineral soil layer most of the hillslope discharge occurred from the soil matrix excluding visible macropores preferential flow pathways in the mineral soil as evidenced by staining tests contributed to stormflow the flow from two macropores just above bedrock was generally very low and responded gradually to rainfall inputs this minor outflow was influenced by preferential flow above bedrock four macropores in the upper right portion of the mineral soil layer did not connect to preferential flow pathways therefore outflow from this group was measured only when large rain events occurred soil moisture amounts and intensities of rainfall and bedrock topography affected heterogeneous outflow from the soil profile the expansion and extension of macropore networks might contribute to stormflow results indicate that hydrometric measurements are needed to support inferences derived from end member mixing analysis and topographic based hydrologic models related to complex preferential flow pathways in forest catchments copyright 2001 john wiley sons ltd

neogene lake systems of central and south eastern europe faunal diversity gradients and interrelations abstract the gastropod diversity of 12 neogene lake systems is evaluated in total 1184 gastropod taxa from 119 localities are recorded deriving from the early miocene rzehakia lake system the early to middle miocene dinarid lake system lake skopje the paratethyan sarmatian lakes and the south german lakes the late miocene lake pannon the pliocene lakes dacia transylvania slavonia kosovo and sostanj as well as the holocene lake petea each lake system is characterised according to its faunistic inventory and endemism according to their gastropod faunas the lakes may be divided into pyrgulid hydrobiid viviparid and planorbid dominated ones the generally high endemism rate is between 60 and 98 species diversity and generic diversity are strongly correlated in contrast neither endemism nor lake size are tightly linked with diversity outstandingly high diversities such as observed for lake pannon are rather a result of the combined effect of autochthonous evolution in a long lived system and accumulation of inherited elements examples of parallel evolution in lymnaeids and planorbids are presented

paleobiogeography of scleractinian reef corals changing patterns during the oligocene miocene climatic transition in the mediterranean abstract during the oligocene miocene greenhouse to icehouse climatic transition the biogeography of reef corals or zooxanthellate like scleractinian corals was gradually changing from a pan tropical tethyan province in the eocene to three reef coral provinces of the western atlantic caribbean indo pacific and mediterranean our reefcoral database encompasses updated and homogenized data on paleoenvironmental and systematics of scleractinian corals occurring in the oligocene and miocene outcrops from circum mediterranean regions provided by most of relatively recently published data in the literature and by the study of published and unpublished collections of coral specimens from the same area including the important collections housed at the mnhn paris and our own collections as there is no validated direct criterion for the identification of the coral zooxanthellate symbiosis in the fossil record and considering the difficulty to use the biogeochemical approaches in the context of this study the subjectivity of the morphological criteria and the relative recent age of the fossil corals we are dealing with a uniformitarian approach has been used for inferring the symbiotic status of scleractinian genera in reefcoral among the 158 genera included in our database 93 can be considered as zooxanthellate and 10 have a doubtful zooxanthellate status this relatively exhaustive database was used to reconstruct the temporal and spatial distribution of scleractinian corals in the mediterranean during the oligocene miocene time in order to discuss the interplaying effects of the global cooling at that time the re organization of the tethyan realm resulting from the african arabian and eurasian plate collision and the emergence of the alpine chains driving the gradual northward movement of the whole region outside the tropical subtropical belt it is shown that the structure of the mediterranean z coral oligocene miocene paleobiodiversity was characterized by many geographically restricted genera with a moderate to short stratigraphical range and a few long ranging widespread genera a major consequence of this structure is that the extinction pattern has proceeded through the preferential extinction of rare occurrence genera through time the potential rapid long distance dispersal of most coral larvae compared to the size of the oligocene miocene mediterranean explains why no biogeographical subprovinces can be distinguished for the z coral fauna on a local scale ecological processes tend to sort coral taxa by limiting z coral development to geographically restricted and discontinuous areas this accounts for the large amount of geographically restricted taxa forming the mediterranean coral fauna the interaction of plate tectonics alpine orogenesis and climate at local to subregional scales exerts strong controls over the spatio temporal distribution of z coral assemblages within the circum mediterranean realm in particular we suggest that the richness and composition of the eastern atlantic coral fauna are indirectly related to the opening and closure of the eastern seaway connection with the indian ocean which controlled the e w circulation of surface waters and hence the westwards dispersal of pelagic larvae at the scale of the whole region the gradual regional climatic change produced by the northwards migration of the entire area superimposed on the global cooling appears in large part responsible for the extinction pattern of z corals through time in the mediterranean biogeographical province

high resolution water content estimation from surface based ground penetrating radar reflection data by impedance inversion 1 mapping hydrological parameter distributions in high resolution is essential to understand and simulate groundwater flow and contaminant transport of particular interest is surface based ground penetrating radar gpr reflection imaging in electrically resistive sediments because of the expected close link between the subsurface water content and the dielectric permittivity which controls gpr wave velocity and reflectivity conventional tools like common midpoint cmp velocity analysis provide physical parameter models of limited resolution only we present a novel reflection amplitude inversion workflow for surface based gpr data capable of resolving the subsurface dielectric permittivity and related water content distribution with markedly improved resolution our scheme is an adaptation of a seismic reflection impedance inversion scheme to surface based gpr data key is relative amplitude preserving data preconditioning including gpr deconvolution which results in traces with the source wavelet distortions and propagation effects largely removed the subsequent inversion for the underlying dielectric permittivity and water content structure is constrained by in situ dielectric permittivity data obtained by direct push logging after demonstrating the potential of our novel scheme on a realistic synthetic data set we apply it to two 2 d 100 mhz gpr profiles acquired over a shallow sedimentary aquifer resulting in water content images of the shallow 3 7 m depth saturated zone having decimeter resolution

calcite graphite thermometry of the franklin marble new jersey highlands abstract we present new stable isotope data for the mesoproterozoic franklin marble from outcrops along an 80 km traverse parallel to and across strike of the structural grain of the western new jersey highlands calcite and dolomite from marble have an average 13c of documentclass aastex usepackage amsbsy usepackage amsfonts usepackage amssymb usepackage bm usepackage mathrsfs usepackage pifont usepackage stmaryrd usepackage textcomp usepackage portland xspace usepackage amsmath amsxtra usepackage ot2 ot1 fontenc newcommand cyr renewcommand rmdefault wncyr renewcommand sfdefault wncyss renewcommand encodingdefault ot2 normalfont selectfont declaretextfontcommand textcyr cyr pagestyle empty declaremathsizes 10 9 7 6 begin document landscape 0 35 mbox textperthousand pm 0 73 mbox textperthousand end document pdb documentclass aastex usepackage amsbsy usepackage amsfonts usepackage amssymb usepackage bm usepackage mathrsfs usepacka

a gastropod based biogeographic scheme for the european neogene freshwater systems abstract for the first time a palaeobiogeographic framework is proposed for european neogene freshwater systems the distribution of 2226 species group taxa of freshwater gastropods from over 2700 miocene and pliocene localities was evaluated the localities were grouped into palaeo freshwater systems based on latest palaeogeographic reconstructions cluster analyses were computed for four time slices i e early miocene middle miocene late miocene and pliocene the analyses demonstrate a generally high degree of provincialism for the neogene freshwater systems and allow the definition of biogeographic units the delimitations are based on the cluster analyses the degree of endemicity and geographical coherence the early miocene is characterised by a relatively low degree of provincialism suggesting the distinction of three regions coinciding with the development of many endemic systems on the dinarian anatolian island and in central europe the middle miocene demonstrates a higher degree of provincialism allowing the definition of six biogeographic regions with the onset of the late miocene the retreat of the central paratethys and development of the huge lake pannon massively shaped faunal evolution and palaeobiogeography in general the formation of the lago mare environment fringing the mediterranean basin as well as the development of several restricted freshwater systems in western europe additionally promoted biogeographic division the increasing provincialism allowed the delimitation of six biogeographic regions three of which could be subdivided into seven dominions with the disappearance of lake pannon and the decline of western european and mediterranean faunas at the miocene pliocene boundary biodiversity hotspots shifted towards eastern and southeastern europe for the pliocene four biogeographic regions five dominions and four provinces were defined most of the here proposed biogeographic units and faunal differences are governed by the varied existence of large long lived systems because of their prolonged duration they immensely influenced the community composition on the family level differences of the relative species richnesses per biogeographic region and the rising rate of endemicity the underlying mechanism for this pattern is the ongoing continentalization of europe triggered by the alpidic orogenesis and the simultaneous retreat of the paratethys sea the continuing restriction of this huge intracontinental sea from the mediterranean promoted the evolution of endemic freshwater faunas the arising long lived systems like lake pannon lake dacia or lake slavonia persisted over several millions of years and stimulated the evolution of highly diverse and endemic faunas

paleogeographic evolution of the late miocene lake pannon in central europe abstract the paleogeographic evolution of lake pannon within the pannonian basin is reconstructed with eight maps ranging from the middle miocene to the early pliocene the maps are based on the distribution of selected biozones and specific fossils and on complementary sedimentological and seismic information our reconstruction shows that the history of lake pannon can be divided into three distinct intervals an initial stage with low water level which resulted in isolation from the sea at about 12 ma and might have led to temporary fragmentation of the lake an interval of gradual transgression lasting until ca 9 5 ma and a long late interval of shrinkage and infilling of sediments that persisted into the early pliocene the deep subbasins of the lake formed during the transgressive interval in more basinward locations than the deep basins of the preceding sarmatian age the southern shoreline running parallel with the sava and danube rivers along the northern foot of the dinarides changed very little during the lifetime of the lake while the northern shoreline underwent profound changes

subsurface lateral preferential flow network revealed by time lapse ground penetrating radar in a hillslope subsurface lateral preferential flow lpf has been observed to contribute substantially to hillslope and catchment runoff however the complex nature of lpf and the lack of an appropriate investigation method have hindered direct lpf observation in the field thus the initiation persistence and dynamics of lpf networks remain poorly understood this study explored the application of time lapse ground penetrating radar gpr together with an artificial infiltration to shed light on the nature of lpf and its dynamics in a hillslope based on our enhanced field experimental setup and carefully refined gpr data postprocessing algorithms we developed a new protocol to reconstruct lpf networks with centimeter resolution this is the first time that a detailed lpf network and its dynamics have been revealed noninvasively along a hillslope real time soil water monitoring and field soil investigation confirmed the locations of lpf mapped by time lapse gpr surveys our results indicated the following 1 increased spatial variations of radar signals after infiltration suggested heterogeneous soil water changes within the studied soil which reflected the generation and dynamics of lpf 2 two types of lpf networks were identified the network at the location of soil permeability contrasts and that formed via a series of connected preferential flow paths and 3 the formation and distribution of lpf networks were influenced by antecedent soil water condition overall this study demonstrates clearly that carefully designed time lapse gpr surveys with enhanced data postprocessing offer a practical and nondestructive way of mapping lpf networks in the field thereby providing a potentially significant enhancement in our ability to study complex subsurface flow processes across the landscape

hillslope threshold response to rainfall 1 a field based forensic approach summary hillslope threshold response to storm rainfall is poorly understood basic questions regarding the type location and flow dynamics of lateral subsurface flow remain unanswered even at our most intensively studied field sites here we apply a forensic approach where we combined irrigation and excavation experiments at the well studied maimai hillslope to determine the typology and morphology of the primary lateral subsurface flowpaths and the control of bedrock permeability and topography on these flowpaths the experiments showed that downslope flow is concentrated at the soil bedrock interface with flowpath locations controlled by small features in the bedrock topography lateral subsurface flow is characterized by high velocities several orders of magnitude greater than predicted by darcy s law using measured hydraulic conductivities at the site we found the bedrock to be moderately permeable and showed that vertical percolation of water into the bedrock is a potentially large component of the hillslope water balance our results suggest that it is the properties of the bedrock topography and permeability that control subsurface flow at maimai and the soil profile plays a less significant role than previously thought a companion paper incorporates these findings into a conceptual model of hydrological processes at the site to explore the generalities of whole hillslope threshold response to storm rainfall

imaging rainfall drainage within the miami oolitic limestone using high resolution time lapse ground penetrating radar 1 the vadose zone of the miami limestone is capable of draining several centimeters of rainfall within a fraction of an hour once the water enters the ground little is known about the flow paths in the oolitic rock a new rotary laser positioned ground penetrating radar gpr system enables centimeter precise and rapid acquisition of time lapse surveys in the field two dimensional 2 d gpr time lapse surveying at a 3 min interval before during and after rainfall shows how buried sand filled dissolution sinks efficiently drain the bulk of the rainwater hourly repeated 3 d imaging of a dissolution sink in response to surface infiltration shows how the wetting front propagates at a rate of 0 6 1 2 m h traversing the 5 m thick vadose zone within hours at the same time some of the water migrates laterally into the host rock guided by stratigraphic unit boundaries average lateral propagation measured over a 28 hour period was of the order of 0 1 m h on a seasonal time frame redistribution involves the entire rock volume comparing 3 d surveys acquired after wet summer and dry winter conditions shows good gpr event correspondence but also time shifts up to 20 ns caused by the change of overall water content within the vadose zone high precision time lapse gpr imaging can therefore be used to noninvasively characterize natural drainage inside the vadose zone ranging from transient loading to seasonal variation

eocene pliocene time scale and stratigraphy of the upper rhine graben urg and the swiss molasse basin smb we present a general stratigraphic synthesis for the upper rhine graben urg and the swiss molasse basin smb from eocene to pliocene times the stratigraphic data were compiled both from literature and from research carried out by the authors during the past 6 years an index of the stratigraphically most important localitites is provided we distinguish 14 geographical areas from the helvetic domain in the south to the hanau basin in the north for each geographical area we give a synthesis of the biostratigraphy lithofacies and chronostratigraphic ranges the relationships between this stratigraphic record and the global sea level changes are generally disturbed by the geodynamic e g subsidence evolution of the basins however global sea level changes probably affected the dynamic of transgression regression in the urg e g middle pechelbronn beds and serie grise corresponding with sea level rise between ru1 ru2 and ru2 ru3 sequences respectively as well as in the molasse basin regression of the umm corresponding with the sea level drop at the ch1 sequence the urgent project upper rhine graben evolution and neotectonics provided an unique opportunity to carry out and present this synthesis discussions with scientists addressing sedimentology tectonics geophysics and geochemistry permitted the comparison of the sedimentary history and stratigraphy of the basin with processes controlling its geodynamic evolution data presented here back up the palaeogeographic reconstructions presented in a companion paper by the same authors see berger et al in int j earth sci 2005

extension and compression related basins in central italy during the messinian lago mare event abstract during the messinian lago mare event in the central mediterranean area compression and extension related basins developed as a consequence of the post tortonian evolution of the tyrrhenian apennines system all these syn tectonic sedimentary basins were characterized by different subsidence rates and sedimentary processes several sections located in different tectonic domains from the tyrrhenian to the adriatic margin of the apennine chain have been investigated s valentino in abruzzo citeriore roccamorice penscosansonesco roccacaramanico and le vicenne sections are located in compression related basins foreland basin system while the tolfa blera sections and the sedimentary succession of mondragone 1 well drilled in the garigliano coastal plain are located in extension related basins hinterland or back arc basins the recognition of ostracod assemblages with paratethyan affinities allows them to be referred to the messinian lago mare event loxoconcha djaffarovi zone this result allows us to consider the tyrrhenian rifting the accretion of the apennine thrust belt and the increase in subsidence rate during the flexuration of the foreland domain as synchronous processes due to the same geodynamical process taking into account the thicknesses of the analysed sedimentary basins different total subsidence rates have been computed for both the compression and extension related basins the syn rift basins that developed on the eastern margin of the northern tyrrhenian basin volterra val di fine and tolfa blera basins recorded a mean total subsidence rate of 1 25 mm a whereas higher subsidence rates affected the eastern margin of the central tyrrhenian basin 5 mm a garigliano coastal plain the differences in horizontal stretching and total subsidence rates that affected the tyrrhenian extensional area correspond to different migration rates of the apennine orogenic system in the northern 10 mm a and central apennines 40 mm a this difference in the total syn rift subsidence rate fits in well with the segmentation model of the tyrrhenian apennines system along a nne ssw lithosphere discontinuity which crosses the system from ancona northern apennines to the r selli lineament in the tyrrhenian basin

pairing geophysical techniques improves understanding of the near surface critical zone visualization of preferential routing of stemflow along coarse roots abstract there is compelling evidence from aboveground observations that trees considerably affect precipitation partitioning through the critical zone however due to the lack of appropriate methods the role of root systems the hidden half of trees on redistributing precipitation and infiltration into and routing through the soil remains inadequately visualized and understood here we designed a novel experiment to pair two non invasive geophysical techniques ground penetrating radar gpr and electrical resistivity tomography ert to trace stemflow through the soil in a forested hillslope after water was released on the trunk of an american beech fagus grandifolia ehrh to induce stemflow we used gpr to locate lateral coarse roots and gpr and ert together to confirm the wetting areas in response to the non uniform transport of stemflow signal changes between time lapse geophysical images were used to reveal both the response time and location of stemflow infiltration into and redistribution through the soil this first known study to investigate the subsurface routing of stemflow by combining gpr and ert revealed that the belowground funneling of stemflow along laterally oriented coarse roots transported water 2 8 m downslope from the study tree in 30 min after stemflow was initiated in situ excavation validated the distribution of lateral roots and lateral root derived preferential flow paths identified in geophysical images confirming the utility of pairing gpr and ert to gain insights into the temporal dynamics and spatial distribution of subsurface routing of stemflow the proposed method visualized and confirmed the funneling effect of roots on belowground water redistribution that contributed to subsurface lateral flow pairing gpr and ert provides a useful combination of geophysical methods to advance our understanding of the complex interactions between plant and soil such as the role of tree roots in soil hydrological process by revealing areas of funneling in the hidden part of the critical zone

mare versus lago mare marine fishes and the mediterranean environment at the end of the messinian salinity crisis during the late messinian c 5 5 ma ago after evaporitic sedimentation and before the pliocene flooding the mediterranean recorded a major environmental change testified by deposition of non marine sediments of the so called lago mare facies such deposits are widespread in the mediterranean basin usually characterized by molluscs and ostracodes of brackish affinity here we present marine fish remains from lago mare deposits of central italy the fossils represented by both articulated skeletons and otoliths were collected from nine stratigraphic horizons of the upper portion of the lago mare sequence of cava serredi tuscany marine euryhaline fishes strongly dominate the assemblages but fully marine stenohaline fishes belonging to the families myctophidae and bythitidae are also present the fossil fish remains are associated with classic lago mare ostracodes and molluscs these fossil fishes clearly demonstrate that normal marine conditions were present at least during the upper interval of the lago mare event implying that the marine refilling of the mediterranean was intra messinian rather early pliocene we argue in favour of the necessity of a new palaeoenvironmental interpretation for the post evaporitic messinian of the mediterranean

pyroxene composition as an indicator in the classification of skarn deposits the chemical compositions of pyroxenes from 46 skarn deposits in japan were statistically examined after compiling published and newly analyzed compositional data in order to put constraints on skarn metallogeny the mn fe ratio and zn content of pyroxene in each deposit are relatively constant and tend to vary regionally in accordance with metal type most pyroxenes of cu fe deposits are characterized by a low mn fe ratio 0 2 and a high zn content 200 ppm pyroxenes of w deposits have an intermediate mn fe ratio around 0 15 and a very high zn content especially those of w sn f deposits 500 ppm the systematic relation between the pyroxene composition and the metal type extends to the mn fe ratio and cd content of skarn sphalerites these compositional features of pyroxenes and sphalerites seem to indicate that the proportion of fe mn zn and cd contents in hydrothermal fluids did not change significantly from the time of pyroxene formation to the period of the later sulfide deposition on the scale of the deposit the mn fe ratio and zn content of skarn pyroxene can serve as an additional aid in the classification and defining of the environment of skarn formation

chronology causes and progression of the messinian salinity crisis the messinian salinity crisis is widely regarded as one of the most dramatic episodes of oceanic change of the past 20 or so million years 1 3 earliest explanations were that extremely thick evaporites were deposited in a deep and desiccated mediterranean basin that had been repeatedly isolated from the atlantic ocean1 2 but elucidation of the causes of the isolation whether driven largely by glacio eustatic or tectonic processes have been hampered by the absence of an accurate time frame here we present an astronomically calibrated chronology for the mediterranean messinian age based on an integrated high resolution stratigraphy and tuning of sedimentary cycle patterns to variations in the earth s orbital parameters we show that the onset of the messinian salinity crisis is synchronous over the entire mediterranean basin dated at 5 96 0 02 million years ago isolation from the atlantic ocean was established between 5 59 and 5 33 million years ago causing a large fall in mediterranean water level followed by erosion 5 59 5 50 million years ago and deposition 5 50 5 33 million years ago of non marine sediments in a large lago mare lake sea basin cyclic evaporite deposition is almost entirely related to circum mediterranean climate changes driven by changes in the earth s precession and not to obliquity induced glacio eustatic sea level changes we argue in favour of a dominantly tectonic origin for the messinian salinity crisis although its exact timing may well have been controlled by the 400 kyr component of the earth s eccentricity cycle

evolution of the freshwater ecosystem the fossil record abstract the freshwater ecosystem may be as old as most life although freshwater life is taxonomically impoverished in comparison with marine and terrestrial biotas and ultimately derived from them it cannot be assumed that freshwater communities have necessarily been less complex in the geologic past than they are today although it is clear they have undergone a number of major changes freshwaters contain not only their own ancient and peculiar groups some with ancestries as far back as the middle paleozoic but they have been a theater for adaptive radiation of more recent immigrants from the land or sea and a way station for still other groups that passed through both from sea to land and the reverse this review summarizes first fossil records in freshwaters for many of these organisms and examines the question of the changing complexity of the freshwater ecosystem through time by looking at the fossil record of continental aquatic habitats

soil layering and preferential flow impacts on seasonal changes of gpr signals in two contrasting soils abstract experimental evidence has shown that soil layering can significantly alter water movement through soil profiles especially in sloping landscapes detailed knowledge of soil layering and its position in the landscape is therefore necessary for determining dynamic subsurface flow in this study we used ground penetrating radar gpr in combination with high resolution real time soil water monitoring to investigate seasonal changes in gpr signals to identify soil horizon interfaces and their impacts on water flow in two contrasting soils the results showed that 1 in the deep rushtown soil located in a concave hillslope gpr reflections in the bw bc and bc c horizon interfaces became clearer as soil became wetter such increased contrast along interfaces was due to the presence of water associated with water restricting bc horizon and lateral flow from upslope area and 2 in the shallow weikert soil located in a planar hillslope gpr reflections in the soil bedrock interface and the weathered unweathered rock interface become intermittent as soil became wetter this scattering of gpr reflection was due to the non uniform distribution of water in fractured shale bedrock and possible tree root effects while wet condition permitted the enhanced detection of water distribution in both soil profiles optimal time for detecting soil layering was different for these two soils wet condition was more suited for detecting water restricting dense layer in the deep rushtown soil while dry season was optimal for identifying the soil bedrock interface in the shallow weikert soil overall this study demonstrates the value of repeated gpr surveys in different seasons to capture subsurface hydrologic processes and the impacts of soil layering and preferential water distribution on seasonal changes of gpr signals it also provides a useful reference for selecting optimal time for gpr survey in the field

zinc lead skarn deposits of the nakatatsu mine central japan several zoned skarns are found in the nakatatsu mine which consists of several zinc lead skarn deposits in the vicinity of the contact between the paleozoic fujikuradani formation and granite porphyry intrusions of tertiary age the skarns are mainly composed of manganoan hedenbergite of limestone origin and grandite andradite of dolerite and limestone origin clinopyroxene was altered in the vicinity of the orebodies to nontronite and clinopyroxene in the same skarn below the orebodies was transformed into garnet thus the relationship between skarns and ores seems to be one of the key points in considering a possible mechanism for ore formation the mode of occurrence of the ores the mineral compositions and the estimated physicochemical environment during ore formation suggest that the principal causes of ore formation are a reduction of the ore forming fluid and a decrease in temperature

how do disconnected macropores in sloping soils facilitate preferential flow runoff from hillslopes is generated by processes such as infiltration excess and saturation overland flow subsurface stormflow and subsurface return flow preferential flow through macropores can affect any one of these runoff generation processes field studies at the hitachi ohta experimental watershed in japan have noted that self organization processes may manifest the connectivity of such subsurface flow paths particularly via macropores from hillslopes to stream channels it is well established from soil physics principles that the connectivity of macropore networks depends on soil wetness and this has been shown experimentally at hitachi ohta where subsurface flow and streamflow respond to thresholds of wetness numerical solutions to the three dimensional richards equation are derived for a sloping soil block containing a population of disconnected macropores of various sizes shapes and orientations solutions for the case of steady water flux applied to the surface of the soil block are evaluated to determine the conditions where the disconnected macropores become active in the flow process results show that subsurface flow is directed through the preferential flow network in the saturated portion of the soil but bypasses the macropores in the drier regions the preferential flow network expands as the degree of saturation increases the expanding network of active macropores leads to less resistance to overall flow in the domain and access to increased volumes of the flow domain although the individual macropores are disconnected it is argued that large localized hydraulic gradients can potentially lead to preferred zones of subsurface erosion in addition to the importance of these findings related to stormflow generation in catchments they add support to the concept of self organization of subsurface flow systems in soils copyright 2010 john wiley sons ltd

preferential flow occurs in unsaturated conditions copyright 2011 john wiley sons ltd because it commonly generates high speed high volume flow with minimal exposure to solid earthmaterials preferential flow in the unsaturated zone is a dominant influence in many problems of infiltration recharge contaminant transport and ecohydrology by definition preferential flow occurs in a portion of a medium that is a preferred part whether a pathway pore or macroscopic subvolume there are many possible classification schemes but usual consideration of preferential flow includes macropore or fracture flow funneled flow determined by macroscale heterogeneities and fingered flow determined by hydraulic instability rather than intrinsic heterogeneity that preferential flow is spatially concentrated associates it with other characteristics that are typical although not defining it tends to be unusually fast to transport high fluxes and to occur with hydraulic disequilibrium within the medium it also has a tendency to occur in association with large conduits and high water content although these are less universal than is commonly assumed predictive unsaturated zone flow models in common use employ several different criteria for when and where preferential flow occurs almost always requiring a nearly saturated medium a threshold to be exceeded may be specified in terms of the following i water content ii matric potential typically a value high enough to cause capillary filling in a macropore of minimum size iii infiltration capacity or other indication of incipient surface ponding or iv other conditions related to total filling of certain pores yet preferential flow does occur without meeting these criteria my purpose in this commentary is to point out important exceptions and implications of ignoring them some of these pertain mainly to macropore flow others to fingered or funneled flow and others to combined or undifferentiated flow modes

catastrophic flood of the mediterranean after the messinian salinity crisis around 5 6 million years ago the mediterranean sea became disconnected from the world s oceans and during the period that followed known as the messinian salinity crisis sea levels fell dramatically as the waters evaporated the water returned about 5 3 million years ago but the details about this the largest known flood in earth s history remain sketchy a study making use of boreholes seismic data and numerical modelling suggests that it was a catastrophic event though it started as a trickle that may have lasted several thousand years as much as 90 of the incoming water was transferred in less than two years such an abrupt flood may have involved peak rates of sea level rise of more than 10 metres a day 5 33 million years ago in an event known as the zanclean flood atlantic waters refilled a mostly desiccated mediterranean sea which had become disconnected from the world s oceans however the nature abruptness and evolution of this flood remain poorly constrained using borehole and seismic data and a model study it is now suggested that 90 per cent of the water was transferred in a short period of a few months to two years with peak rates of sea level rise in the mediterranean possibly reaching more than 10 metres per day the mediterranean sea became disconnected from the world s oceans and mostly desiccated by evaporation about 5 6 million years ago during the messinian salinity crisis1 2 3 the atlantic waters found a way through the present gibraltar strait and rapidly refilled the mediterranean 5 33 million years ago in an event known as the zanclean flood4 the nature abruptness and evolution of this flood remain poorly constrained4 5 6 borehole and seismic data show incisions over 250 m deep on both sides of the gibraltar strait that have previously been attributed to fluvial erosion during the desiccation4 7 here we show the continuity of this 200 km long channel across the strait and explain its morphology as the result of erosion by the flooding waters adopting an incision model validated in mountain rivers this model in turn allows us to estimate the duration of the flood although the available data are limited our findings suggest that the feedback between water flow and incision in the early stages of flooding imply discharges of about 108 m3 s 1 three orders of magnitude larger than the present amazon river and incision rates above 0 4 m per day although the flood started at low water discharges that may have lasted for up to several thousand years our results suggest that 90 per cent of the water was transferred in a short period ranging from a few months to two years this extremely abrupt flood may have involved peak rates of sea level rise in the mediterranean of more than ten metres per day

messinian salinity crisis regulated by competing tectonics and erosion at the gibraltar arc the persistent shallow connection between the atlantic ocean and the mediterranean sea that caused the messinian salinity crisis may have been sustained by a balance between tectonic uplift and erosion due to inflow about six million years ago a series of geological factors drastically reduced the exchange of water between the atlantic ocean to the mediterranean sea through what is now the strait of gibraltar the resulting widespread salt precipitation in the mediterranean linked to a decrease in sea level of about 1 5 kilometres due to evaporation is known as the messinian salinity crisis the exact mechanism that caused the crisis remains uncertain here daniel garcia castellanos and antonio villasenor propose a competition between the obstruction of the gibraltar arc seaway by tectonic uplift and its erosional deepening by water inflow controlled by the resulting changes in sea level difference across the gibraltar arc as a possible mechanism for the crisis the messinian salinity crisis1 2 5 96 to 5 33 million years ago was caused by reduced water inflow from the atlantic ocean to the mediterranean sea resulting in widespread salt precipitation and a decrease in mediterranean sea level of about 1 5 kilometres due to evaporation3 the reduced connectivity between the atlantic and the mediterranean at the time of the salinity crisis is thought to have resulted from tectonic uplift of the gibraltar arc seaway and global sea level changes both of which control the inflow of water required to compensate for the hydrological deficit of the mediterranean1 4 however the different timescales on which tectonic uplift and changes in sea level occur are difficult to reconcile with the long duration of the shallow connection between the mediterranean and the atlantic5 needed to explain the large amount of salt precipitated here we use numerical modelling to show that seaway erosion caused by the atlantic inflow could sustain such a shallow connection between the atlantic and the mediterranean by counteracting tectonic uplift the erosion and uplift rates required are consistent with previous mountain erosion studies with the present altitude of marine sediments in the gibraltar arc6 7 and with geodynamic models suggesting a lithospheric slab tear underneath the region8 9 10 the moderate mediterranean sea level drawdown during the early stages of the messinian salinity crisis3 5 can be explained by an uplift of a few millimetres per year counteracted by similar rates of erosion due to atlantic inflow our findings suggest that the competition between uplift and erosion can result in harmonic coupling between erosion and the mediterranean sea level providing an alternative mechanism for the cyclicity observed in early salt precipitation deposits and calling into question previous ideas regarding the timing of the events that occurred during the messinian salinity crisis1

origin of the charnockites of the louis lake batholith wind river range wyoming the 2 63 ga louis lake batholith a calc alkalic pluton exposed opxand fayalite fay bearing felsic igneous rocks inin wind river range of western wyoming consists of minor diorite clude opdalite opx granodiorite enderbite opx tonalquartz diorite granodiorite and granite at shallow structural levels ite and mangerite opx monzonite le maitre et al the batholith is pyroxene free but at deeper levels all units of the 1989 many of these rock names are not commonly batholith contain pyroxenes on its northern margin the batholith used the term charnockite sensu lato is typically applied was emplaced at p 5 6 kbar t 775 800 c fo2 at to any opx bearing granitoid regardless of its bulk fmq fayalite magnetite quartz 1 5 to fmq 1 8 and composition for example the charnockite suite of south ah2o 0 1 along the southern margin of the batholith the india includes enderbites opdalites and charnockites emplacement pressure was 3 kbar the batholith includes two howie 1955 the nigerian suite includes charnockite compositional series the peraluminous high ree series is rich in and opdalite olarewaju 1987 and that of lofoten is k2o and displays larger feo feo mgo the metaluminous associated with mangerites malm ormaasen 1978 low ree series has less k2o and smaller feo feo mgo because the terms enderbite and opdalite are so rarely in the boulder canyon area most of the rocks belong to the lowused in this paper we use the term charnockite for all ree series the nd pb and sr initial isotopic compositions of opx bearing granitic rocks where it is important to both series vary and do not correlate with sio2 abundance relatively describe a specific rock type we use opx as a varietal constant fe mg ratios over a wide range of sio2 and the large modifer to the rock name e g opx granodiorite instead variation in initial isotopic compositions indicate that the sources of opdalite for the louis lake batholith include older wyoming province crustin the 1980s workers in southern india recognized and mantle derived mafic melts the calc alkalic nature of the areas where biotite bearing granitic gneiss had been boulder canyon charnockites indicates that there is no special cconverted to pyroxene bearing gneiss along fluid pathtype magma instead charnockites will form in any rock type if ways janardhan et al 1982 friend 1985 this led to the water activity is low enough the term charnockitization srikantappa et al 1985 and the concept that charnockite is a metamorphic rather than an igneous rock as a result charnockite has been used incorrectly by some workers as a synonym for

paleogeographic evolution of the southern pannonian basin 40ar 39ar age constraints on the miocene continental series of northern croatia the pannonian basin originating during the early miocene is a large extensional basin incorporated between alpine carpathian and dinaride fold thrust belts back arc extensional tectonics triggered deposition of up to 500 m thick continental fluvio lacustrine deposits distributed in numerous sub basins of the southern pannonian basin extensive andesitic and dacitic volcanism accompanied the syn rift deposition and caused a number of pyroclastic intercalations here we analyze two volcanic ash layers located at the base and top of the continental series the lowermost ash from mt kalnik yielded an 40ar 39ar age of 18 07 0 07 ma this indicates that the marine continental transition in the slovenia zagorje basin coinciding with the onset of rifting tectonics in the southern pannonian basin occurs roughly at the eggenburgian ottnangian boundary of the regional paratethys time scale this age proves the synchronicity of initial rifting in the southern pannonian basin with the beginning of sedimentation in the dinaride lake system beside geodynamic evolution the two regions also share a biotic evolutionary history both belong to the same ecoregion which we designate here as the illyrian bioprovince the youngest volcanic ash level is sampled at the glina and karlovac sub depressions and both sites yield the same 40ar 39ar age of 15 91 0 06 and 16 03 0 06 ma respectively this indicates that lacustrine sedimentation in the southern pannonian basin continued at least until the earliest badenian the present results provide not only important bench marks on duration of initial synrift in the pannonian basin system but also deliver substantial backbone data for paleogeographic reconstructions in central and southeastern europe around the early middle miocene transition

origin of a carbonate hosted fe mn ba as pb sb w deposit of langban type in central sweden the sjogruvan deposit is one of the langban type fe mn oxide deposits hosted by marble interbeds within svecofennian metavolcanic rocks in the bergslagen region central sweden mineralogical and geochemical studies have been carried out to clarify the premetamorphic origin of this type of deposit which is set apart from most other mn mineralizations by a significant enrichment in ba as sb pb w and be contained by various oxyminerals the principal ore types at sjogruvan are 1 hematite quartz magnetite 2 hausmannite calcite tephroite and 3 braunite celsian phlogopite the mn ores are compositionally akin to modern mn deposits formed by submarine hydrothermal processes with a high mn fe ratio and low contents of co ni th u and ree and likely owe their existence to similar mechanisms of formation pb isotope data indicate that the metal source and timing of deposition is similar to the major stratabound base metal and iron deposits in bergslagen all the key elements have been leached from the local felsic volcanic units and were deposited on the sea floor the excellent mn fe separation occurred in an eh ph gradient that essentially corresponded to the mixing zone of hydrothermal solutions and seawater the braunite ore is chemically distinct from the hausmannite ore with a high concentration of refractory elements al ti zr and a positive ce anomaly which indicate a detrital hydrogenetic contribution to its protolith carbon isotope 13c values around 0 relative pdb suggest that carbonates in the deposit formed directly from seawater

sulphur isotope compositions in the ammeberg zn pb ore deposit south central sweden genetic implications the distribution of sulphur isotope compositions in the ammeberg sulphide ore deposit is discussed the 34s values for various sulphides show a complex pattern of fluctuations between isotopic equilibrium and non equilibrium conditions this feature as well as the observed variations in the 34s values of galena and sphalerite are interpreted to have originated from successive pulses of sulphide forming solutions on the basis of geological field criteria and sulphur isotope data the ammeberg deposit is considered to be a typical distal mineralization belonging to the volcanic exhalative group of ore deposits the banded structure of the ore the spatial separation of pb and zn and the presence of discrete persistant ore layers probably relate to the type of convective system that created the mineral forming solutions and to the various processes taking place when the brines were expelled onto the sea floor

rise and fall of the paratethys sea during the messinian salinity crisis abstract extremely thick evaporite units were deposited during the so called messinian salinity crisis msc 5 96 5 33 ma in a deep mediterranean basin that was progressively disconnected from the atlantic ocean a crucial but still poorly understood component in messinian evaporite models is the connectivity between mediterranean and paratethys i e the former black sea domain inadequate stratigraphic correlations and insufficient age control for paratethys sediments have so far hampered a thorough understanding of hydrological fluxes and paleoenvironmental changes here we present a new chronology for the eastern paratethys by integrating biostratigraphic and paleomagnetic data from mio pliocene sedimentary successions of romania and russia we show that a major flooding event from the mediterranean surged the paratethys basins at the maeotian pontian boundary 6 04 million years ago this indicates that sea level in both mediterranean and paratethys was high at the beginning of the msc we argue in favor of changes in paratethys mediterranean connectivity to initiate the msc in combination with elusive tectonic processes in the gibraltar arc a subsequent fall of paratethyan water level closely coincides to the mediterranean isolation event corresponding in age to the glacial cycles tg12 14 5 60 5 50 myr in the latest messinian a major climate change towards more humid conditions produced a positive hydrological balance and likely a transgression in the paratethys although our stratigraphic resolution cannot exclude a possible relation to the pliocene flooding of the mediterranean here

a comparative study of fossil and extant algaenans using ruthenium tetroxide degradation in this study the chemical structure of algaenans isolated from the freshwater algae tetraedron minimum pediastrum boryanum and botryococcus braunii are compared with their fossil counterparts by means of ruo4 oxidation the results show that the algaenans investigated are preserved in sediments with only minor structural alterations however product mixtures from ruo4 degradation of the fossil algaenans exhibit a broader distribution of oxidation products than freshly isolated algaenans indicating that the fossil biopolymers contain a greater proportion of ether cross links which maybe an effect of diagenetic alteration or different algal strains despite these differences fossil algaenans can still be recognised chemically on the basis of the specific ruo4 oxidation products even after 50 ma of sediment burial

lago mare and the messinian salinity crisis evidence from the alboran sea s spain this paper provides a new environmental sedimentological and stratigraphic context of the lago mare deposits from the north alboran region and clarifies their chronologic location with respect to the messinian salinity crisis we present new micropaleontological data dinoflagellate cysts calcareous nannoplankton planktonic foraminifers correlated with field observations and offshore seismic interpretations we show that the lago mare event known in three onshore localities rio mendelin near malaga zorreras near sorbas gafares near nijar follows the marine reflooding of the mediterranean basin which ended the messinian salinity crisis chronologically these lago mare deposits last from the latest messinian to the early zanclean in fact the first influx of paratethyan organisms is revealed by the dinoflagellate cyst record from near malaga within a gilbert type fan delta overlying the messinian erosional surface invading molluscs and or ostracods may have persisted in lagoonal coastal areas more or less affected by discontinuous marine influxes sorbas and nijar the malaga area is convenient for a paleogeographic and sedimentary reconstruction which shows the prevalent forcing of sea level changes during the time interval 5 600 5 332 ma at the difference of the usually solicited prevalent tectonics the studied lago mare event is the third episode resulting in such a paleobiological assemblage in the mediterranean region and corresponds to the final two way water exchange at high sea level between the mediterranean and the former paratethys it documents the onset of the modern marine circulation in the mediterranean after the reflooding ending the messinian salinity crisis

petedunnite caznsi 2 o 6 a new zinc clinopyroxene from franklin new jersey and phase equilibria for zincian pyroxenes

late cenozoic increase in accumulation rates of terrestrial sediment how might climate change have affected erosion rates abstract accumulation rates of terrestrial sediment have increased in the past few million years both on and adjacent to continents although not everywhere apparently erosion has increased in elevated terrain regardless of when last tectonically active or what the present day climate in many regions sediment coarsened abruptly in late pliocene time sparser data suggest increased sedimentation rates at 15 ma approximately when oxygen isotopes in benthic foraminifera imply high latitude cooling if climate change effected accelerated erosion understanding how it did so remains the challenge some obvious candidates such as lowered sea level leading to erosion of continental shelves or increased glaciation account for increased sedimentation in some but not all areas perhaps stable climates that varied slowly allowed geomorphic processes to maintain a state of equilibrium with little erosion until 3 4 ma when large oscillations in climate with periods of 20 000 40 000 years developed and de

circum mediterranean oligo miocene biogeographic evolution the gastropods point of view based on studies in iran qom basin esfahan sirjan basin zagros mountains in turkey mut and sivas basins in the mesohellenic basin and in northeastern egypt a new palaeobiogeographic concept for the oligocene and miocene in the circum mediterranean area with special emphasis on the distribution patterns of gastropod faunas is presented a very strict biogeographic terminology is proposed to avoid the common fusion of geographic faunistic and geodynamic terms in the palaeontologists jargon our main interest focuses on the affinities and the faunistic interactions between the early mediterranean and the early indo pacific regions during the oligo miocene especially the role of the early indo pacific faunas as the mythic centre of origination of early neogene european mollusc faunas as often vaguely indicated in the literature is critically evaluated this leads to the establishment of a mediterranean iranian province and a western indian eastern african province as palaeobiogeographic subunits of the western tethys region during the oligocene due to major geodynamic and related biogeographic changes in the early miocene the western tethys region no longer existed and was replaced by the proto mediterranean atlantic region for the area of the paratethys the palaeobiogeographic unit danubian province which includes the protocaspian subprovince is proposed furthermore the underrated transatlantic communication of the oligo miocene nearshore mollusc faunas is demonstrated altogether this paper is a contribution to the discussion on the biogeographic concepts classification and nomenclature in palaeontology as initiated by westermann palaeogeogr palaeoclimatol palaeobiogeogr 158 2000 1 13 163 2000 49 68 2002 elsevier science b v all rights reserved

new developments in the upper pliocene pleistocene stratigraphic units of the dacian basin eastern paratethys romania abstract as a result of multidisciplinary investigations carried out in the last two decades the knowledge of the pliocene and quaternary stratigraphy from dacian basin has increased considerably new lithostratigraphic units were revealed for example trajkovo fm romanian vl deni fm v n tori fm pleistocene and other units have been reassessed izvoarele fm tulucesti fm romanian a new biozonation based on molluscan fauna from the late pliocene nsm11 nsm12 and pleistocene qm1 qm9 deposits made possible a more accurate subdivision and cronostratigraphical assignments and correlations many localities with romanian mammal associations lupoaia dr nic podari tetoiu leu etc were reviewed adding new taxa in the faunal list with implications for accurately establishing host deposit ages these studies together with bio magnetostratigraphic investigations led to revision of the romanian stage boundaries and subdivisions pelendavian valahian and to outline several new pleistocene chronostratigraphic units the argedavian dinogetian ilfovian stages and milcovian uzunian netindavian musaisian substages finally one major achievement consisted in the pliocene pleistocene boundary relocation in the dacian basin in agreement with its new position at 2 6 ma in the mediterranean realm

the mid hungarian line a zone of repeated tectonic inversions abstract the mid hungarian line is a major tectonic feature of the intra carpathian area separating two terranes of different origin and tectonic structure although this tectonic line was known from borehole records it has not been described in seismic sections the study presents interpreted seismic lines crossing the supposed trace of the mid hungarian line these seismic sections show north dipping normal faults and thrust faults as well as cross cutting young strike slip faults a complex tectonic history is deduced including intra oligocene early miocene thrusting middle miocene extension local late miocene inversion and late miocene pliocene normal faulting and left lateral wrenching in the light of our seismic study we think that the best candidate for the mid hungarian line is a north dipping detachment fault beneath large masses of neogene volcanics the auxiliary structures to the north seen on seismic sections suggest that it moved as a south vergent thrust fault during the palaeogene early miocene which later was reactivated as a set of normal faults the northern alcapa unit overrode the southern tisza dacia unit along this fault zone the same relative positions are observed in the northern termination of the line other structures along the supposed trace of the line are north dipping normal or strike slip faults which frequently were reactivated as smaller thrust faults during the late neogene palaeogene early miocene thrusting along the line might be the result of the opposite tertiary rotations of the two major units as suggested by palaeomagnetic measurements and earlier models

hydrological processes letters topographic controls on subsurface storm flow at the hillslope scale for two hydrologically distinct small catchmetns controls on hillslope ow pathways are still not well understood despite the many di erent studies reported since the pioneering work of hewlett 1961 in a wide range of recent modelling studies it has been assumed that ow directions can be related to hydraulic gradients derived from surface topography this assumption leads to believable maps of predictions of soil saturation and is convenient because of the increasing availability of digital terrain maps dtms the validity of the resulting spatial patterns throughout the watershed however have not been fully assessed although see the discussion in beven et al 1995 and the recent studies of nyberg 1996 and crave and gascuel odoux 1997 this results from the di culty of obtaining adequate spatial coverage of hydrological variables and the scale problem of relating point measurements to predictions at the dtm grid scale recent hillslope analyses of soil moisture distributions have identi ed that ow paths do not necessarily converge to hollow regions anderson 1982 that they may require dynamic spatial representations barling et al 1994 and that their prediction using topographically derived indices have had mixed results burt and butcher 1986 moore and thompson 1996 spatial representations of topographically driven indices therefore need further exploration a possible way forward is to conduct more detailed studies of the dynamics of subsurface ow at the hillslope scale analysis of a natural hillslope combines integrated trench ow and point scale soil moisture measurements coupled with a detailed understanding of surface and subsurface features such data provide a more comprehensive assessment of the assumption used in many modelling studies that hillslope ow is controlled by surface topography in this letter we address the question of whether it is appropriate to use surface topography to describe hillslope ow paths or if it is not more appropriate to use subsurface gradients relating to the soil bedrock interface or the hydrologically impeding layer we present examples for two hillslopes in di erent hydrogeological climatic settings analyses of the distribution of topographic index patterns derived from digital terrain analysis for both surface and subsurface topography are related to observational patterns of subsurface storm ow along arti cial trench face sections

on the formation and evolution of the pannonian basin constraints derived from the structure of the junction area between the carpathians and dinarides 1 the large number and distribution of rollback systems in mediterranean orogens infer the possibility of interacting extensional back arc deformation driven by different slabs the formation of the pannonian back arc basin is generally related to the rapid miocene rollback of a slab attached to the european continent a key area of the entire system that is neglected by kinematic studies is the connection between the south carpathians and dinarides in order to derive an evolutionary model we interpreted regional seismic lines traversing the entire serbian part of the pannonian basin the observed deformation is dominantly expressed by the formation of miocene extensional detachments and half grabens the extensional geometries and associated synkinematic sedimentation that migrated in time and space allow the definition of a continuous and essentially asymmetric early to late miocene extensional evolution this evolution was followed by the formation of few uplifted areas during the subsequent latest miocene quaternary inversion the present day extensional geometry changing the strike across the basin is an effect of the clockwise rotation of the south carpathians and apuseni mountains in respect to the dinarides our study infers that the carpathian rollback is not the only mechanism responsible for the formation of the pannonian basin an additional middle miocene rollback of a dinaridic slab is required to explain the observed structures furthermore the study provides constraints for the pre neogene orogenic evolution of this junction zone including the affinity of major crustal blocks obducted ophiolitic sequences and the sava suture zone

did the mediterranean marine reflooding precede the mio pliocene boundary paleontological and geochemical evidence from upper messinian sequences of tuscany italy abstract the events related to the messinian salinity crisis are among the most deeply investigated of earth s history according to the current hypothesis of neogene paleogeographic evolution approximately 5 5 ma ago after evaporitic sedimentation and before the mio pliocene boundary the mediterranean was characterized by the widespread development of non marine environments inhabited by molluscs and ostracods of brackish affinity the messinian post evaporitic deposits that testify such a dramatic environmental change are commonly referred to as lago mare and have been reported from several outcrops and boreholes throughout the entire mediterranean basin the origin of lago mare conditions is commonly interpreted as the result of the synergistic effect of both the humid climatic conditions and change of the drainage patterns at the mediterranean scale with the capture of paratethyan brackish waters a few recent studies however suggest that such a scenario probably represents an oversimplification of the original context from both a paleogeographical and paleoenvironmental point of view unfortunately the results of these studies have never been commonly accepted and the proposed evidences have been considered questionable in this paper we describe the fish assemblages from the lago mare deposits of two localities cava serredi and podere torricella located in the neogene hinterland basins of tuscany central italy these assemblages consists of a mixture of marine euryhaline and stenohaline taxa suggesting that the depositional environments were characterized by permanently open connections with a marine basin filled with normal marine waters in order to better define the paleontological significance of these upper messinian fish assemblages the oxygen carbon and strontium isotopic composition of fish otoliths and other fossils has been measured these isotopic compositions are strongly indicative of the presence of normal marine conditions close to the depositional environments testified by the sedimentary sequences thereby implying that the interpretation of the geochemical results are consistent with those derived from the paleoecological analyses of the fish assemblages based on the integrated paleoichthyological geochemical approach discussed in this paper it is possible to unambiguously demonstrate that normal marine rather than fresh or brackish waters were present in the mediterranean at least during the upper part of the lago mare event providing an unquestionable evidence that the marine refilling of the basin preceded the mio pliocene boundary

a conceptual model of preferential flow systems in forested hillslopes evidence of self organization preferential flow paths are known to be important conduits of subsurface stormflow in forest hillslopes earlier research on preferential flow paths focused on vertical transport however lateral transport is also evident in steep forested slopes underlain by bedrock or till macropores consisting of decayed and live roots subsurface erosion surface bedrock fractures and animal burrows form the basis of a backbone for lateral preferential flow in such sites evidence from field studies in japan indicates that although individual macropore segments are generally 0 5 m in length they have a tendency to self organize into larger preferential flow systems as sites become wetter staining tests show clear evidence of interconnected macropore flow segments including flow within decayed root channels and subsurface erosion cavities flow in small depressions of the bedrock substrate fracture flow in weathered bedrock exchange between macropores and mesopores and flow at the organic horizon mineral soil interface and in buried pockets of organic material and loose soil here we develop a three dimensional model for preferential flow systems based on distributed attributes of macropores and potential connecting nodes e g zones of loose soil and buried organic matter we postulate that the spatially variable and non linear preferential flow response observed at our japan field site as well as at other sites is attributed to discrete segments of macropores connecting at various nodes within the regolith each node is activated by local soil water conditions and is influenced strongly by soil depth permeability pore size organic matter distribution surface and substrate topography and possibly momentum dissipation this study represents the first attempt to characterize the spatially distributed nature of preferential flow paths at the hillslope scale and presents strong evidence that these networks exhibit complex system behaviour

pre glacial topography of the european alps we present a topographic reconstruction of the european alps prior to quaternary glaciation based on the assumption that this topography was a steady state fluvial landscape eroding according to a stream power law but with spatially variable channel steepness we find high pre glacial channel steepness in the western alps and on the harder rocks of the basement and metamorphic nappes while lower values are often associated with weaker alpine flysch deposits the reconstructed pre glacial river network also provides an estimate of distribution and magnitude of glacial erosion and associated isostatic adjustment suggesting an increase of valley scale topographic relief and decrease of mean elevation throughout glaciation

piping and pipeflow in a deep peat catchment abstract natural pipes are common in many upland blanket peats yet little is known about pipe network morphology or pipeflow processes most information on soil piping comes from the shallow peaty podzols of the welsh uplands where monitoring suggests that pipes may be important contributors to streamflow this paper presents information on piping and pipeflow from a deep upland blanket peat catchment in the pennine hills of northern england pipe outlets are found throughout the soil profile ranging from the underlying substrate at 3 m depth to pipes which are within a few centimetres of the surface mean pipe diameters range from 3 to 70 cm some pipes are over 150 m long slopes in the catchment are less steep than those usually associated with soil piping continuous flow records were obtained from 15 gauging sites on 8 separate pipes the pipeflow response from deep blanket peat was found to be different to that reported in the shallow peaty podzols of the welsh uplands the distinction between ephemeral and perennial pipe types does not appear to be useful within the deep pennine blanket peat response times from all of the pipes are short even from pipes deep within the peat at the same time pipes have a prolonged recession limb such that they maintain low flow for longer periods than most other runoff production processes within the catchment pipeflow contributes around 10 of the streamflow volume but can at times contribute up to 30 soil pipes may therefore be far more important in some upland peat catchments than previous work has hitherto suggested

magnetostratigraphy and radio isotope dating of upper miocene lower pliocene sedimentary successions of the black sea basin taman peninsula russia abstract we present a new chronology for the upper miocene to pliocene deposits of the black sea basin based on high resolution magnetostratigraphic data coupled with 40 ar 39 ar dating from the 475 m long zheleznyi rog section on the taman peninsula russia this section comprises the stratigraphic interval of the khersonian to kimmerian regional stages of the eastern paratethys our magnetostratigraphic record is based on biogenic and early diagenetic greigite components and yields a magnetostratigraphic sequence of 8 polarity zones a volcaniclastic ash layer at the upper part of the khersonian is radio isotopically dated at 8 69 0 18 ma the age of the khersonian meotian transition arrives at 8 6 or 8 2 ma which is significantly younger than earlier estimates the new age has important consequences for the hipparion datum in the eastern paratethys and implies that all vallesian fossil sites are younger than 11 2 ma the meotian stage has a total duration of 2 2 to maximum 2 6 myr and is marked by multiple erosional events the end of the paratethys sea is dated at 5 5 ma when the black sea becomes isolated from the caspian sea the dacian basin and the mediterranean

facies analysis of a 1 9 ga continental margin back arc felsic caldera province with diverse zn pb ag cu au sulfide and fe oxide deposits bergslagen region sweden the bergslagen mining district in south central sweden has been a major metal producer for more than 1 000 years in geologic terms bergslagen is the intensely mineralized part of a large early proterozoic mainly 1 90 1 87 ga felsic magmatic region of mainly medium to high metamorphic grade in the baltic shield the district contains a diverse range of ore deposit types including banded iron formation magnetitecalc silicate skarn manganiferous skarn and carbonate hosted iron ore apatite bearing iron ore stratiform and strata bound zn pb ag cu au sulfide ores and w skarn most ore deposits occur in hydrothermally altered metavolcanic rocks and associated metalimestones and skarns this study is a field oriented regional facies analysis based on recognition of primary volcanic and sedimentary features through the strong overprints of hydrothermal alteration deformation and metamorphism the region is interpreted as an extensional probably back arc active continental margin magmatic region it evolved through stages of intense magmatism thermal doming and crustal extension followed by waning extension waning volcanism thermal subsidence reversal from extension to compressional deformation regional metamorphism and structural inversion the volcanic successions comprise interfingering proximal near vent medial volcano flanks and distal volcano margin facies associations of rhyolitic pyroclastic caldera volcanoes and subordinate dacite rhyolite complexes nonwelded to poorly welded pyroclastic flow and fallout units and their rapidly resedimented subaerial and subaqueous equivalents are the most abundant volcanic facies subvolcanic porphyritic intrusions and cryptodomes are also abundant the pyroclastic debris was shed from mainly shallow water and subaerial proximal areas to shallow and moderately deep water above and below storm wave base distal areas most ore deposits formed during the regional waning volcanic stage and occur in medial to distal facies associations that comprise rhyolitic ash siltstone limestone and vitric crystal sandstone and breccia these mineralized facies associations were deposited in subaqueous environments mainly below the fair weather wave base but locally above the storm wave base water depths are interpreted to have been mainly 10 to 500 m with local deeper areas although the ore deposits occur in medial to distal facies associations many occur above or laterally adjacent to subsided volcanic vent complexes this suggests a spatial temporal and possible genetic relationship between several ore deposit types and the late magmatic stage of these volcanic centers except for the apatite bearing iron deposits it is uncertain if the ores are genetically related to specific magmatic hydrothermal events from specific volcanoes this is possible especially for the base metal sulfide deposits which have intense localized footwall alteration in felsic volcanic rocks however an important role of the volcanic centers may have been to provide strong positive pertubations or magmatic hydrothermal input to the regional convective geothermal system the main zn pb ag cu au ore deposits span a range between two end member types stratiform ash siltstone hosted sea floor deposits that have similarities to some stratiform sediment hosted zn pb ag deposits especially the broken hill type deposits and strata bound volcanic associated limestone skarn subsea floor replacement deposits that more closely resemble felsic volcanic associated massive sulfide deposits facies models are presented for both the banded iron formations are interpreted as chemical suspension deposits rhythmically interbedded with rhyolitic ash siltstone the skarn iron ores are strata bound in limestones and include metamorphosed sedimentary ores and metasomatic replacements apatite bearing iron ores differ in setting from the other ores in being formed within a dacitic intrusive complex that may be the root zone of a dacite rhyolite volcanic center

hydrological connectivity of soil pipes determined by ground penetrating radar tracer detection soil pipes are common and important features of many catchments particularly in semi arid and humid areas and can contribute a large proportion of runoff to river systems they may also signi cantly in uence catchment sediment and solute yield however there are often problems in nding and de ning soil pipe networks which are located deep below the surface ground penetrating radar gpr has been used for non destructive identi cation and mapping of soil pipes in blanket peat catchments while gpr can identify subsurface cavities it cannot alone determine hydrological connectivity between one cavity and another this paper presents results from an experiment to test the ability of gpr to establish hydrological connectivity between pipes through use of a tracer solution sodium chloride was injected into pipe cavities previously detected by the radar the gpr was placed downslope of the injection points and positioned on the ground directly above detected soil pipes the resultant radargrams showed signi cant changes in re ectance from some cavities and no change from others pipe waters were sampled in order to check the radar results changes in electrical conductivity of the pipe water could be detected by the gpr without data post processing when background levels were increased by more than approximately twofold it was thus possible to rapidly determine hydrological connectivity of soil pipes within dense pipe networks across hillslopes without ground disturbance it was also possible to remotely measure travel times through pipe systems the passing of the salt wave below the gpr produced an easily detectable signal on the radargram which required no post processing the technique should allow remote sensing of water sources and sinks for soil pipes below the surface the improved understanding of owpath connectivity will be important for understanding water delivery solutional and particulate denudation and hydrological and geomorphological model development copyright 2004 john wiley sons ltd

paleogeography of the upper rhine graben urg and the swiss molasse basin smb from eocene to pliocene twenty paleogeographic maps are presented for middle eocene lutetian to late pliocene times according to the stratigraphical data given in the companion paper by berger et al this volume following a first lacustrine continental sedimentation during the middle eocene two and locally three rupelian transgressive events were identified with the first corresponding with the early rupelian middle pechelbronn beds and the second and third with the late rupelian serie grise fischschiefer and equivalents during the early rupelian middle pechelbronn beds a connection between north sea and urg is clearly demonstrated but a general connection between north sea urg and paratethys via the alpine sea is proposed but not proved during the late rupelian whereas in the southern urg a major hiatus spans early aquitanian to pliocene times early and middle miocene marine brackish and freshwater facies occur in the northern urg and in the molasse basin omm osm however no marine connections between these basins could be demonstrated during this time after the deposition of the molasse series a very complex drainage pattern developed during the late miocene and pliocene with a clear connection to the bresse graben during the piacenzian sundgau gravels during the late miocene pliocene and quaternary sedimentation persisted in the northern urg with hardly any interruptions the present drainage pattern of the rhine river from alpine area to the lower rhine embayment was not established before the early pleistocene

paleomagnetic and geochronologic constraints on the geodynamic evolution of the central dinarides the geodynamic evolution of the dinaride mountains of southeastern europe is relatively poorly understood especially in comparison with the neighboring alps and carpathians here we construct a new chronostratigraphy for the post orogenic intra montane basins of the central dinarides based on paleomagnetic and 40ar 39ar age data a first phase of basin formation occurred in the late oligocene a second phase of basin formation took place between 18 and 13 ma concurrent with profound extension in the neighboring pannonian basin our paleomagnetic results further indicate that the dinarides have not experienced any significant tectonic rotation since the late oligocene this implies that the dinarides were decoupled from the adjacent adria and the tisza dacia mega units that both underwent major rotation during the miocene the dinaride orogen must consequently have accommodated significant shortening this is corroborated by our ams data that indicate post middle miocene shortening in the frontal zone wrenching in the central part of the orogen and compression in the hinterland a review of paleomagnetic data from the adria plate which plays a major role in the evolution of the dinarides as well as the alps constrains rotation since the early cretaceous to 48 10 counterclockwise and indicates 20 of this rotation took place since the miocene it also shows that adria behaved as an independent plate from the late jurassic to the eocene from the eocene onwards coupling between adria and africa was stronger than between adria and europe adria continued to behave as an independent plate the amount of rotation within the adria dinarides collision zone increases with age and proximity of the sampled sediments to undeformed adria these results significantly improve our insight in the post orogenic evolution of the dinarides and resolve an apparent controversy between structural geological and paleomagnetic rotation estimates for the dinarides as well as adria

metamorphic ore remobilization in the hallefors district bergslagen sweden constraints from mineralogical and small scale sulphur isotope studies the marble and metavolcanic hosted pb zn ag sb as deposits of the hallefors district located in the palaeoproterozoic bergslagen ore province south central sweden comprise both stratabound sulphides and discordant ag rich sulphide sulphosalt veins the complex sulphide sulphosalt assemblages of the alfrida jan olof mines at hallefors were investigated by a combination of ore microscopy electron microprobe analysis and in situ laser sulphur isotope analysis the massive ore is characterized by positive and homoge neous d 34 s 1 4 to 2 7 v cdt whereas vein hosted sulphides and sulphosalts exhibit similar but generally less positive to slightly negative d 34 s 0 6 to 2 0 comparison of the observed ore mineral assemblages with calculated phase equilibria in the sys tem fe as s o h and isotopic fractionation as a function of temperature oxygen fugacity and ph indi cates that the vein type mineralization was formed from relatively reduced and rather alkaline hydrothermal fluids at these reduced conditions fractionation of d 34 s via changes of fo2 is insignificant and thus the isotopic signatures of the vein minerals directly reflect the com position of the sulphur source we therefore conclude that the vein type ore essentially inherited the sulphur isotope signature from the pre existing massive sulp hides via metamorphic remobilization at approximately 300 400c and 2 3 kbar scales of remobilization observable are on the order of about 5 mm to 30 cm overall the sulphide sulphosalt assemblages from the alfrida jan olof mines exhibit d 34 s values which are comparable to a majority of metasupracrustal hosted deposits in the bergslagen province thereby suggesting a common origin from ca 1 90 1 88 ga volcanic hydro thermal processes