modification and preservation of environmental signals in speleothems speleothems are primarily studied in order to generate archives of climatic change and results have led to significant advances in identifying and dating major shifts in the climate system however the climatological meaning of many speleothem records cannot be interpreted unequivocally this is particularly so for more subtle shifts and shorter time periods but the use of multiple proxies and improving understanding of formation mechanisms offers a clear way forward

speleothem based quaternary research in croatian karst a review abstract speleothems as secondary carbonate deposits precipitate in the cave environment from the water originally sourced from the ocean transferred via atmosphere through soil and epikarst into the cave system as such they archive valuable information on the ongoing changes in the atmosphere biosphere hydrosphere and lithosphere which may be used for palaeoenvironmental reconstructions especially for the quaternary period speleothem based quaternary research in croatia started in the 1960 s with the utilization of the flowstone and speleothems whose radiometric ages 14c and u th provided constrained chronological framework for underlying fossils or archaeological material mainly without any further palaeoenvironmental interpretations since the 1990 s several studies have used speleothems for the reconstruction of particular phases of speleogenesis while in the early 2000 s investigation on submerged speleothems started with the aim to reconstruct quaternary relative sea level changes along the eastern adriatic coast only after that thorough research on subaerial speleothems from the different regions of the croatian karst has been initiated usually associated with monitoring programs this paper gathers the most important speleothem based studies displaying potential of this still understudied but promising area in the terms of palaeoclimate and palaeoenvironmental changes in a wider european and global context

sedimentological and palaeoecological integrated analysis of a miocene channelized carbonate margin matese mountains southern apennines italy abstract lower middle miocene temperate marine carbonates occur in the matese mountains southern apennines italy these carbonates formed in an open shelf depositional system with an uneven margin 10 km long and up to 6 km wide shelf margin morphology shows multiple submarine channelized carbonate deposits which are dominated by coralline red algae and subordinate bryozoans two main channel networks pietraroia and regia piana channels with their sedimentary bodies were analysed the studied submarine channels grew by sediment accumulation as prograding bodies on a tectonic modelled substrate shallow water rhodalgal skeletal debris from moderately re mobilized up to significantly re worked built up the complex channel system fills in which sedimentary lenses overlapped and partially amalgamated one another when they were still unlithified the early channelized succession is characterized by parautochthonous bryozoan floatstone and rhodolith bryozoan floatstone representing soft muddy substrates in a low water turbulence and high turbidity setting the rhodoliths dominated by melobesioid coralline algae are sub discoidal and sub spheroidal in shape with a characteristic loosely packed inner arrangement these sediments whose latter portion underwent submarine diagenetic processes incipient to evoluted hard grounds were eroded and successively covered by shallower water gravitative deposits constituted by rhodolith floatstone rudstone their rhodoliths constituted by melobesioids mastophoroids and subordinate lithophylloids and sporolithaceans are mainly spheroidal sub spheroidal in shape with subordinate sub discoidal specimens with massive and laminar inner arrangements the lack in early lithification can be drawn back to the physiography of the channelized shelf margin to the active tectonic as well as to the temperate type carbonate dominant biogenic components the depositional surface profile and local hydrodynamic conditions were the major factors controlling sedimentary facies which differ in their relative proportions of dominant components their internal structures and sedimentary body geometries

provenance and formation of the red palaeosol and lithified terra rossa like infillings on the island of susak a high resolution and chronological approach abstract red palaeosol rp covering the carbonate basement exposed at the bottom of the loess section and lithified terra rossa like materials situated in cavities ltr1 and karstified fissures ltr2 in cretaceous limestones were investigated by means of high resolution approach to give a systematic and deeper palaeopedological insight into reddish materials and the exposed red palaeosols on the island of susak both selected geochemical indicators of weathering al si na k al and fed fet and provenance la ce as well as detailed mineralogical analysis clearly showed differences among ltr1 ltr2 and rp respectively ltr1 and ltr2 represent erosional remains of different soils that existed on the surface of the limestone bedrock prior to the formation of the rp ltr2 has the highest ztr zircon tourmaline rutile index index and contains bauxite minerals gibbsite and boehmite clays kaolinite and mixed layer clay minerals and haematite ltr2 bears characteristics of reworked bauxitic materials mixed with other soils that existed on the surface of the carbonate basement those materials might have been mixed and transported until they were captured in the karstified fissure and subsequently interlocked with calcite veins and lithified this might have happened from the eocene age on our attempt to resolve the age of ltr2 formation more precisely using palaeomagnetic investigations did not give unambiguous results because the extremely viscous behaviour of the ltr2 samples hinders the acquisition of a stable remanent magnetisation if we exclude the secondary calcite ltr1 bears typical mineralogical and geochemical characteristics e g fed fet ratio similar to those of istrian terra rossa insoluble residues of cretaceous limestone might have been the main parent materials for the ltr1 formation while the most likely additional fluxes influencing terra rossa formation on the island of susak were aeolian dust and flysch the erosion remains ended in limestone cavities and were mixed with cm to dm sized angular and subangular limestone clasts and subsequently interlocked with calcite veins and lithified the investigated rp profile comprised the following mineral horizons bwb1 bwb2 bwb3 r the rp formed in a lithologically uniform material that dominantly presents a mixture of loess and partly remains of older soils e g rounded clay coatings not related to macrovoids that existed on the surface of the cretaceous limestone fed fet ratio in rp reflects a low degree of weathering of fe containing primary silicates therefore we can conclude that the rp does not fit a rather limited variation of selected fe oxide characteristics typical for terra rossa the investigated rp was classified independently of the overlying material the full name of the palaeosol that we classified is as follows hypereutric chromic cambisol episiltic endoloamic since no reversal of the emf was recorded in the rp we concluded that the rp formed during the brunhes epoch luminescence dating was applied to establish the age of the rp based on the acquired data we assume that the rp very likely formed during the penultimate interglacial ois7

oxygen and hydrogen isotopic variations between adjacent drips in three caves at increasing elevation in a temperate coastal rainforest vancouver island canada abstract the interpretation of speleothem paleoenvironmental records requires understanding of spatial temporal variations in vadose drip water chemistry and isotopic composition this study reports on intra and inter cave differences in d 18o and electrical conductivity using 18 monthly water samples from three adjacent drips all drips showed isotopic seasonal signals despite varied patterns of drip hydrology there was overlap in isotopic ranges at 1 sd between all three caves in contrast with the expected 18o depletion of 0 15 to 0 5 100 m of ascent observed in standard precipitation the isotopic seasonality was approximated with sine curves and compared to a gnip data set from victoria 300 km to the south the d and 18o drip isotopes lagged the victoria record by 155 26 days and 165 50 days respectively the longest lag was at the slowest drip sea level while the shortest lag 87 days for 18o 550 m asl implies a short residence time paradoxically from the drip with the highest mean electrical conductivity vadose residence time was less than one climatic year reflecting a combination of negligible matrix porosity in the host rock and super humid climatic conditions beneath the epikarst drip hydrology was evidently by simple piston flow phase shifted drip isotope records showed excellent agreement with sea level mean monthly air temperatures at the tahsis meteorological station over the study period the d and 18o drip amplitudes were damped on average 74 and 73 respectively compared to the victoria data the drips at 740 m asl are tightly aligned to the global mean meteoric water line gmwl and 18o depleted the drips at 550 m asl and at sea level plot along the gmwl or between it and the victoria lmwl with the exception of the slowest drip sea level which displays some seasonal evaporitic enrichment the findings quantify substantial intra and inter cave variation of d and 18o in drips having a wide range of drip type and volume of flow sufficient to mute the altitudinal isotopic lapse rate in this local coastal rainforest environment

the effects of grain density variation on turbidity currents and some implications for the deposition of carbonate turbidites abstract sediment grains in carbonate turbidity currents vary greatly in size shape surface texture and density depending on the evolution of the source carbonate platform in time and space facies character and distribution may vary from traditional siliciclastic turbidite models not only because of the difference in composition but also because variation in grain properties influences flow and depositional behavior experimental gravity flows were generated to investigate one control on this variation the experiments used silicon carbide 3214 kg m 3 and glass ballotini 2650 kg m 3 with a similar grain size distribution in varying proportions to assess the influence of particle density on flow and sedimentation processes mixed particle density flows were more efficient than single particle density flows flow propagation was faster in flows with greater initial bulk density determined by grain density and suspended sediment concentration with mixed particle suspensions flow propagation velocity was maintained for longer due to the presence of low settling velocity particles as a result mixed particle density flows transported more sediment downstream compared to single particle density flows of similar initial suspended sediment volume concentration because of the wider range of grain types in carbonate turbidity currents they may more effectively transport coarse sand grade sediment to more distal sites in a marine basin compared to siliciclastic counterparts of equivalent initial volume this results in differences in bed and facies geometry and distribution

a late holocene climate record in stalagmites from modric cave croatia few terrestrial holocene climate records exist from south eastern europe despite its important geographical position as a transitional climatic zone between the mediterranean and mainland continental europe here we present new petrographic and stable isotope data for two holocene speleothems from modric cave croatia 44 15 n 15 32 e a coastal adriatic site 120 m inland modern meteorological and cave conditions have been monitored for 2 years to understand the links between climate variability and stable isotope time series records in speleothems typical of a mediterranean type climate a negative water balance exists between april and september so that recharge of the aquifer is restricted to the winter months the weighted mean 18o of the rainfall is 5 96 2 2 83 and the weighted mean d h rainfall value is 36 83 2 19 95 slightly above the global meteoric water line but well below the mediterranean meteoric water line modern calcite from the tops of each stalagmite exhibits 18o values that are close to isotopic equilibrium with their respective drip water values unfortunately the relatively young ages and low uranium contents ca 50 p p b of both stalagmites hamper the use of u series dating radiocarbon dates have been used instead to constrain their chronology using a dead carbon correction apart from some isotope stage 3 material ca 55 ka both stalagmites were deposited during the late holocene climatic conditions during the late holocene are inferred to have been sufficiently wet to maintain stalagmite growth and any hiatuses appear to be relatively short lived inferred changes in the stalagmite diameters during deposition are linked to 13c and 18o variations indicating alternating periods of drier and wetter conditions drier conditions are inferred for the late roman ages warm period and the mid medieval warm period wetter conditions are associated with the little ice age copyright 2012 john wiley sons ltd

oligo miocene rift of sardinia and the early history of the western mediterranean basin the geodynamic evolution of the western mediterranean basin in spite of many studies is still uncertain there is some consensus for interpreting this basin as a kind of small oceanic marginal basin its opening has generally been related to a subduction process which was active during the oligocene miocene somewhere east of sardinia corsica1 7 as the margins of the basin are deeply buried below miocene to present sediments direct lithological and stratigraphical data which could explain the events responsible for its formation are rare8 10 or missing altogether to obtain such data detailed field studies have been undertaken in sardinia fig 1 and the first results are presented here this approach is justified by the fact that in that island oligocene and miocene sediments were deposited in a rift fossa tettonica sarda of verdabasso11 which is the easternmost arm of the complex rift system that affected the european plate during oligocene and miocene times one of these arms evolved towards a small oceanic basin the western mediterranean or algero provencal basin while others such as the gulf of valencia and the sardinia rift aborted and remained at the rift stage its exceptional exposures make it possible to examine the sardinia rift to clarify the sequence of events which created it and to establish a sedimentological model which we believe is directly applicable to the western mediterranean basin

marine cements in mid tertiary cool water shelf limestones of new zealand and southern australia large areas of southern australia and new zealand are covered by mid tertiary limestones formed in cool water shelf environments the generally destructive character of sea floor diagenesis in such settings precludes ubiquitous inorganic precipitation of carbonates yet these limestones include occasional units with marine cements 1 within rare in situ biomounds 2 within some stacked cross bedded sand bodies 3 at the top of metre scale subtidal carbonate cycles and 4 most commonly associated with certain unconformities the marine cements are dominated by isopachous rinds of fibrous to bladed spar interstitial homogeneous micrite and interstitial micropeloidal micrite often precipitated sequentially in that order internal sedimentation of microbioclastic micrite may occur at any stage the paradox of marine cemented limestone units in an overall destructive cool water diagenetic regime may be explained by the precipitation of cement as intermediate mg calcite from marine waters undersaturated with respect to aragonite in some of the marine cemented limestones aragonite biomoulds may include marine cement sediment internally suggesting that dissolution of aragonite can at times be wholly marine and not always involve meteoric influences we suggest that marine cementation occurred preferentially but not exclusively during periods of relatively lowered sea level probably glacio eustatically driven in the mid tertiary at times of reduced sea level there was a relative increase in both the temperature and the carbonate saturation state of the shelf waters and the locus of carbonate sedimentation shifted towards formerly deeper shelf sites which now experienced increased swell wave and or tidal energy levels fostering sediment abrasion and reworking reduced sedimentation rates and freer exchange of sediment pore waters energy levels were probably also enhanced by increased upwelling of cold deep waters onto the southern ocean margins of the australasian carbonate platforms where water mass mixing warming and loss of co2 locally maintained critical levels of carbonate saturation for sea floor cement precipitation and promoted the phosphate glauconite mineralization associated with some of the marine cemented limestone units

climate caving in to new chronologies speleothems formed in caves such as stalagmites can be dated precisely and are increasingly providing detailed and accurate records of past climates

fault plane solutions for northeastern united states earthquakes abstract fault plane solutions for eight earthquakes occurring in the northeastern united states have been determined using p wave first motions and a computer algorithm for picking all valid solutions the predominant mechanism in the area is thrust faulting however the direction of the p axis is not consistent throughout the entire area in central new england maine new hampshire the p axis trends nearly e w in southeastern new england the p axis trends n s to ne sw in the adirondacks region of new york the p axis trends ne sw as previously reported by yang and aggarwal 1981 although the stress distribution appears to be complicated as in the central united states street et al 1974 an underlying e w compressive stress may exist in the new england area these small earthquakes may represent the response to local stress concentrations

seismotectonics of northeastern united states and adjacent canada data for local earthquakes recorded by a network of stations in northeastern united states and adjacent canada were analyzed to study the seismicity the relationship between earthquakes and known faults the state of stress and crustal and upper mantle velocity structure in addition portable seismographs were deployed in the field to study aftershocks as a result accurate locations for about 364 local earthquakes 2 mb 5 and 22 focal mechanism solutions were determined a comparison of the spatial distribution of these events 1970 1979 with historical earthquakes 1534 1959 reveals that seismic activity in the northeast is relatively stationary in space those areas that have had little or no seismicity historically are relatively aseismic today whereas the historically active areas are also active today the instrumental locations historical seismicity and focal mechanism solutions show an internal consistency that help us distinguish two distinct seismogenic provinces 1 the adirondack western quebec province is a northwesterly trending zone of seismic activity about 200 km wide and at least 500 km long extending from the se adirondacks into western quebec canada thrust faulting on planes striking nnw to nw appears to predominate and the inferred axis of maximum horizontal compression is largely uniform and trends wsw nearly parallel to the calculated absolute plate motion of north america little or no seismicity is found where anorthosite outcrops at the surface correlations between gravity anomalies and earthquake locations suggest that seismic activity in this zone is localized to regions of steep ne or sw gradient in bouguer anomalies this zone does not appear to extend southeastward to boston as proposed by some workers 2 the appalachian province is a northeasterly trending zone of seismic activity extending from northern virginia to new brunswick canada highangle reverse or thrust faulting on n to ne trending planes appears to predominate the western margin of this province however appears to be relatively aseismic we attribute this relative lack of activity to one or more of the following the presence of igneous activity postdating rifting of africa from north america the occurrence of intense metamorphism during the acadian orogeny which may have annealed preexisting faults and the predominance of ductile as opposed to brittle deformation in the geologic past the inferred axis of maximum horizontal compression along the eastern margin of the appalachians is rather uniform and trends w wnw almost perpendicular to the magnetic lineations offshore we suggest that this w wnw compression reflects the gravitational force arising from horizontal density variations in the oceanic lithosphere as it cools and moves away from spreading centers

distinct phases of relative sea level changes in the central adriatic during the last 1500 years influence of climatic variations abstract we present a new sea level reconstruction for the past 1500 years based on biological indicators from the central adriatic islands biogenic littoral rims built by the coralline rhodophyte lithophyllum byssoides were found on the particularly exposed sites on the rocky coasts of the islands of vis ravnik and bisevo in croatia the presence of thick and well developed lithophyllum rims considered to be precise 10 cm sea level indicators points directly to the rising sea level environment biogenic rims were mapped measured and sampled for 14c dating the obtained results point to four phases of sea level changes the sea level was near stable from around 550 till 770 cal ad in the dark ages cold period dacp then during the medieval climate anomaly mca 770 till 1330 cal ad the sea level increased at a rate of 0 71 mm yr during the little ice age lia 1330 till 1640 cal ad it was near stable again later the sea level started to rise at a much higher rate particularly during the current warm period cwp these data were compared with local predictions derived from a glacio hydro isostatic models associated with the last glacial cycle if the isostatic eustatic component is separated this area seems to have almost stable tectonic conditions during the past 1500 years our results show that the large algal rims most likely grew during near stable sea level conditions that occurred during two relatively colder periods in the past 1500 years they also reveal that well developed up to 1 8 m wide upper levels of algal rims were formed during 300 years of stabilisation throughout the lia

post rift sequence architecture and stratigraphy in the oligo miocene sardinia rift western mediterranean sea abstract rift basins provide important sedimentary archives to reconstruct past tectonic and climatic conditions understanding their sedimentary history is however largely hampered by the competing influence of tectonic versus climatic forcing the aim of this study is to comprehend the effects of local to regional tectonic and global climatic eustatic changes on shallow marine depositional systems in the sardinia rift western mediterranean sea for this purpose the stratigraphic and depositional relations of a mixed siliciclastic carbonate ramp at the porto torres basin margin were studied along extensive proximal to distal transects three depositional sequences ds1 to ds3 of late burdigalian to early serravallian age have been identified which are separated by erosional unconformities each contains a lower transgressive part and an upper regressive part the former includes shoreface sandstone ds2 or coral reef ds3 deposits on the proximal ramp and channelized sheet sandstone ds1 or basinal mudstone ds2 ds3 deposits on the distal ramp typically recording an upsection trend of sediment starvation the latter is represented by basinward prograding coralline red algal carbonate wedges due to enhanced shallow water carbonate production rates in the long term the depositional evolution from ds1 to ds3 reveals basin margin progradation associated with decreasing siliciclastic supply integrated calcareous nannoplankton foraminiferal pectinid biostratigraphy links the depositional sequences to third order sea level cycles and allows to correlate the erosional unconformities at the top of ds1 and ds2 with the bur 5 lan 1 and lan 2 ser 1 sequence boundaries the improved sequence stratigraphic framework enables better regional and global correlations this shows that rhodalgal carbonate slopes started prograding in the western branch of the sardinia rift during the late burdigalian because 1 of a worldwide bloom of rhodalgal facies and 2 decreasing tectonic activity at the transition from the syn rift to the post rift stage caused a continuous reduction of the siliciclastic sediment input

polygenetic soil formation on late glacial loess on the susak island reflects paleo environmental changes in the northern adriatic area abstract a polygenetic soil formed on late glacial loess on the island of susak was investigated by means of high resolution depth approach to give pedosedimentary and palaeoenvironmental reconstructions of the late glacial holocene pedosequence the complete polygenetic profile a 2c1 2c2 3btb 4ck defined as eutric leptic regosol geoabruptic siltic ruptic over argic horizon over loess deposit is a result of the interaction of the sediments loess with environmental conditions from the late glacial throughout the holocene both normal pedogenesis and erosion sedimentation driven pedogenesis influenced its development therefore this profile bears valuable imprints of climate vegetation land surface and land use changes in this part of the adriatic area for the time period covering the past 16 ka the 4ck horizon is a remnant of an a c soil profile whose incipient formation corresponds to a steppe like palaeo vegetation and a semi humid to semi arid palaeo climate the 3btb horizon has blocky structure common clay coatings and infillings that are related to the walls of channel macrovoids increased cia al si and ba sr ratios due to the increase of the al and clay contents highest fet fed mnt and mnd values due to abundant redox concentrations and specific clay mineralogy since the obtained age of the loess deposit 4ck horizon underlying the 3btb horizon is 16 1 1 3 ka can be correlated to the late glacial maximum i e ois 2 we find that the period of the bolling allerod warming might have enabled the formation of the highly weathered 3btb horizon within a luvisol like soil after the period of surface stability a period of forest decay and surface instability took place resulting with the erosion of the luvisol the 3btb horizon was then covered with a homogeneous loess material whose deposition can presumably be related to the younger dryas period inside of which the horizons 2c1 and 2c2 are recognized both these horizons are negligibly affected by pedogenesis and contain artefacts the incipient soil formation in the upper part of the profile along with the irregular lower boundary of the a horizon and the lithic discontinuity between the a horizon and the 2c1 horizon points to the possibility of a very recent and minor aeolian deposition however one should not overlook the potential impacts of human activities and or colluvial depositions on the properties of the a 2c1 and 2c2 horizons

disequilibrium carbon and oxygen isotope fractionation in recent cave calcite comparison of cave precipitates and model data abstract speleothem proxy data provide important information in continental palaeo climate research due to their precise chronology and wide geographic distribution despite a continuously growing number of field and numerical studies designed to study stable isotope fractionation effects many aspects remain a matter of debate here carbon and oxygen isotope ratios from cave drip water and calcite precipitates sampled on watch glasses in the bunker cave western germany are compared with the values expected for isotopic equilibrium furthermore the field data are compared with the results of a numerical model simulating stalagmite growth and stable isotope ratios two drip sites with different drip rates were investigated drip site ts 1 is characterised by a high drip rate and drip water of this site is characterised by a high saturation index with respect to calcite ts 1 shows no evidence of prior calcite precipitation conversely drip site ts 8 shows a low drip rate and drip water from this site is characterised by a low saturation index ts 8 shows evidence of prior calcite precipitation whereas the mean 13 c dic values of the drip water are significantly different between the two drip sites the mean 18 o drip water values are similar calcite precipitation rates are higher at watch glass site u i corresponding to drip site ts 1 this is probably due to the higher si calcite and drip rate the 18 o and 13 c values of the calcite precipitated on watch glasses u iv corresponding to drip site ts 8 are significantly higher than those of the calcite collected on watch glasses u i calcite precipitation occurs close to isotopic equilibrium at watch glass site u i whereas the calcite precipitated at watch glass site u iv shows clear evidence of isotopic disequilibrium the results suggest that cave calcites precipitated at lower drip rates have higher 13 c and 18 o values than predicted by equilibrium precipitation furthermore our data show that stalagmites from the same cave which are fed by drip water with similar 18 o values may have different 18 o calcite values the 13 c and 18 o values predicted by the numerical model are generally lower by 1 9 and 0 8 respectively than those of the natural cave calcite nevertheless the first order trends observed in the cave data are well reproduced by the model the offset between cave and model data is probably due to the fractionation factors used in the model

rhodalgal bryomol assemblages in temperate type carbonate channelized depositional systems the early miocene of the sarcidano area sardinia italy

carbonate lithofacies as paleolatitude indicators problems and limitations abstract detailed study of miocene carbonates in the mediterranean region and their analogues on modern carbonate shelves in the mediterranean sea brazil and other areas reveals at least three major types of carbonate platform lithofacies in addition to the classic tropical coral reef chlorozoan lithofacies a chloralgal lithofacies similar to the chlorozoan but without hermatypic corals b rhodalgal lithofacies characterized by abundant encrusting coralline algae and c molechfor lithofacies consisting of benthic foraminifers molluscs echinoids bryozoans and barnacles these carbonate lithofacies present complex distribution patterns seemingly related primarily to latitude and depth that control water temperature although other factors e g water circulation river discharge suspended sediment controlling water salinity and temperature nutrient content light penetration etc also play important roles chloralgal and rhodalgal lithofacies can be considered two transitional terms between the two end members the chlorozoan lithofacies which characterizes shallow tropical shelves and the molechfor lithofacies which characterizes colder and or deeper areas detailed textural and sequential analysis are required for satisfactory interpretation of these lithofacies in ancient rocks

dating large infrequent earthquakes by damaged cave deposits the long term recurrence patterns of past earthquakes are of considerable consequence for hazard assessments and have implications for earthquake physics we introduce a rigorously dated record of earthquakes from an extensive number of well preserved pre seismic and postseismic precipitates from caves located off the dead sea transform we dated events directly at the paleoseismic contact by means of a novel correlation method with the oxygen isotope record of the speleothems recovered in one of the caves within the 185 k y covered we dated 38 seismite samples these stem from 13 18 earthquakes with a mean recurrence interval of 10 14 k y we show that the deformational events dated in the study caves complement independent near fault paleoseismic records by tem poral correlation with the earthquakes recorded therein this opens up a significant new avenue of earthquake research that will provide precise dating and observational con straints on large infrequent earthquakes

the last glacial aeolian record of the island of susak croatia as seen from a high resolution grain size and rock magnetic analysis abstract the loess palaeosol record on the island of susak in croatia is a unique archive of late glacial climate changes in the adriatic region possibly even in the wider area on susak up to 90 m of thick quaternary sediments were deposited and are accessible for detailed palaeoclimate reconstructions in this paper the results of a high resolution grain size and rock magnetic investigation on the last glacial upper pleniglacial sand pit section from susak are presented in spite of its significant thickness the sand pit section does not represent a continuous record it is a result of a very dynamic environment there the deposition of dust and formation of loess has been interrupted by pedogenesis periods of increased sand accumulation erosion due to slope wash and water activity redeposition and wildfires and all in the time period of about 10 000 years of the upper pleniglacial as seen from the irsl dating results the grain size data clearly show a shift towards coarser grain sizes which differs from typical loess regions such predominance of the coarser grained over the fine grained fraction very likely resulted from the predominance of deposition over pedogenesis increased wind activity and proximal source of material the rock magnetic signal preserved in the sediment also differs compared to loess palaeosol records from other regions the susceptibility values are several times higher than in the records from the pannonian basin and from typical eurasian loess both the increased susceptibility values and the grain size are very likely the result of a significant proximal material input from the po river plain

advancements in the use of speleothems as climate archives abstract speleothems have become a cornerstone of the approach to better understanding earth s climatic teleconnections due to their precise absolute chronologies their continuous or semicontinuous deposition and their global terrestrial distribution we review the last decade of speleothem related research building off a similar review by mcdermott 2004 in three themes i investigation of global teleconnections using speleothem based climate reconstructions ii refinement of climate interpretations from speleothem proxies through cave monitoring and iii novel technical methods of speleothem based climate reconstructions speleothem records have enabled critical insight into the response of global hydroclimate to large climate changes this includes the relevant forcings and sequence of climatic responses involved in glacial terminations and recognition of a global monsoon response to climate changes on orbital and millennial time scales we review advancements in understanding of the processes that control speleothem 13 c values and introduce the idea of a direct atmospheric pco 2 influence we discuss progress in understanding kinetic isotope fractionation which with further advances may help quantify paleoclimate changes despite non equilibrium formation of speleothems this feeds into the potential of proxy system modeling to consider climatic hydrological and biogeochemical processes with the objective of quantitatively interpreting speleothem proxies finally we provide an overview of emerging speleothem proxies and novel approaches using existing proxies most recently technical advancements made in the measurement of fluid inclusions are now yielding reliable determinations of paleotemperatures

displaced re worked rhodolith deposits infilling parts of a complex miocene multistorey submarine channel a case history from the sassari area sardinia italy abstract in the sassari area north western sardinia italy the miocene porto torres sub basin sequences represent the complex multistorey mixed carbonate siliciclastic submarine feature called the sassari channel during the late burdigalian early serravallian repeated terrigenous supplies from uplifted paleozoic crystalline substrata fed the sassari channel system by means of turbidity and locally hyper concentrated turbidity flows shelfal areas were the source of terrigenous clasts but open shelf rhodalgal foramol carbonate areas were very productive and largely also contributed to the channel infilling re worked sands and skeletal debris were discontinuously re sedimented offshore as pure terrigenous mixed and or carbonate deposits major sediment supply was introduced between the latest burdigalian and the start of the middle langhian during which a large amount of carbonate mixed and siliciclastic sediments reached the porto torres basin sassari channel i contributions from shallow proximal source areas typify the lower intervals unit a in marginal sectors of the channel upward these evolve into autochthonous rhodolith deposits winnowed by strong currents in relatively shallow well lit settings within a complex network of narrow tidally controlled channels unit d locally bearing coral assemblages conversely re sedimented rhodoliths from the units b and c accumulated under conditions of higher turbidity in deeper parts of the channel taxonomically diversified rhodoliths point to the mixing of re deposited skeletal components from different relatively deep bathmetric settings in the latest early langhian major re sedimentation episodes resulting in large prograding bodies unit d triggered by repeated regression pulses in a frame of persistent still stand during these episodes photophile assemblages dwelled in the elevated margin sectors of the channel a significant latest early langhian drop in relative sea level resulted in impressive mass flows involving early cemented channel margin and levee blocks and culminated in the formation of major erosional surface er e such events seemingly correlate with the long term global cooling trend of the mid miocene climatic transition episodes of middle langhian re sedimentation concluded with the channel abandon phase after which new erosive episodes followed overall this led to a shift in the sassari channel ii with phases presumably started during the earlymost serravallian subsequent to the major sea level drop at the langhian serravallian boundary

speleothem palynology an undervalued tool in quaternary studies palynological analysis of cave sediments in particular the analysis of pollen from speleothems is not a widely adopted approach to palaeoenvironmental studies in the british isles this disregard of speleopalynology may be due to the lack of understanding of the cave pollen taphonomy and uncertainty and suspicion as to what cave pollen spectra actually represent however a number of studies of pollen from caves have been carried out particularly in belgium france and spain which have demonstrated speleothem pollen spectra to be representative of contemporary vegetation above the cave with pollen generally well preserved speleothems have the distinct advantage over other pollen sources that they can be dated by high precision tims u th dating up to an order of magnitude further back in time than 14c dating of organic sediments would allow this potentially allows previously unconstrained middle pleistocene palynological records to be precisely and accurately dated thus providing a geochronologically controlled terrestrial record of palaeoenvironmental change this paper presents a timely review of speleothem palynology aiming to eliminate biases and misconceptions and illustrate the enormous potential this unique source of palaeoenvironmental data holds particularly in providing accurately dated pollen records from previously understudied environments and time periods

anatomy of a submarine channel system and related fan in a foramol rhodalgal carbonate sedimentary setting a case history from the miocene syn rift sardinia basin italy abstract during aquitanian burdigalian times thick mixed carbonate siliciclastic successions were deposited in basins located on the grabens and half grabens along the oligo miocene sardinia rift basin locally active tectonics sea level variations and ecological factors combined to control the development and distribution of foramol carbonate factories as well as the remobilisation and the redeposition of carbonate sediments into the adjacent deeper areas in the isili basin foramol rhodalgal carbonate factories developed on submerged structural highs which resulted from pre and syn sedimentary tectonics these carbonate factories were periodically shaved mainly during negative sea level oscillations and the sediments removed were funnelled towards the basin through a complex submarine channel network which included a tributary belt one main channel isili channel and the related fan the isili channel is up to 1 km wide 60 100 m deep and includes two stacked channel complexes each built up by several minor order channel units complex strata geometries characterise the isili channel and its related architectural elements e g overbank levee margin and channel thalweg which also include up to 15 m high bedforms individual channel complexes were temporally related to individual fan systems whose spatial distribution and internal geometry were strongly controlled by the type and rate of sediment accumulation and in turn by relative sea level oscillations facies associations include sandy to cobble sized gravity flow and bottom current deposits as well as megabreccias characterised by impressive displaced and tilted blocks which resulted from major channel margin collapses detailed analysis has led to the reconstruction of the internal geometry and depositional architecture of these carbonate bodies and to the determination of the main controlling factors the dimension and distribution of channel and channel related depositional bodies have been accurately determined this information provides a useful tool to analyse less extensively exposed analogues and to model foramol shelf to basin transitions and related channel and fan systems

late holocene climate variability in the adriatic sea central mediterranean planktic and benthic foraminifera assemblages from a set of sediment cores collected on the adriatic shelf and the southern adriatic deep basin provide compelling evidence of submillennial scale environmental changes during the last 6000 years repeated peaks in globigerinoides sacculifer represent warm dry intervals including the mediaeval warm period the roman age the late bronze age and the copper age the last occurrence lo of g sacculifer 550 years bp approximates the base of the little ice age lia significant turnovers in the structure of the water column reflect changes in the rate of formation and depth of flow of the north adriatic dense water naddw and the levantine intermediate water liw about 7500 years bp the benthic oxygen isotope records mark the timing when the naddw formation intensified on the slope and shifted to its modern route about 5500 years bp when sea level reached its modern high stand oxygen isotope records of intermediate planktic dwellers indicate a northward intrusion of the liw on the slope the oscillating isotope trends during the last five millennia document a discontinuous invasion of liw into the central adriatic possibly reflecting short term climate changes with weakened liw production during colder and wetter intervals

state of stress and intraplate earthquakes in the united states recently compiled data on the state of stress have been used to define stress provinces in the conterminous united states in which the orientation and relative magnitude of the horizontal principal stresses are fairly uniform the observed pattems of stress constrain mechanisms for generating intraplate lithospheric stresses coupled with new information on geologic structure and tectonism in seismically active areas of the midcontinent and east these data help to define some characteristics common to these areas and to identify key questions regarding why certain faults seem to be seismically active

isotopic characterization of cave environments at varying altitudes on the eastern adriatic coast croatia implications for future speleothem based studies abstract an important step in the implementation of paleoclimate reconstructions from speleothems cave carbonate deposits is to evaluate the sensitivity of the host cave environment to regional climate accordingly we studied three caves at different altitudes 74 m 570 m and 1250 m a s l along a transect from the dalmatian islands to velebit mountain peaks in coastal croatia to characterize their environments in terms of each cave s suitability to host speleothems that would be capable of yielding robust paleoclimate reconstructions we conducted cave microclimate 2 years and dripwater 1 year monitoring and analysed the isotopic composition of precipitation cave dripwater and modern spelean calcite as for the water isotopic imprints the isotopic values of meteoric waters reaching the two lower altitude caves in spite of an altitude difference of 500 m lie on local meteoric water lines lmwls of similar slope and intercept 2 h 6 61 18 o 4 92 and 2 h 6 69 18 o 6 86 their slopes lower than that of gmwl indicate enhanced evaporation during the warm season as expected the lmwl of the highest cave region 2 h 7 83 18 o 14 45 resembles the slope of the gmwl but the values of deuterium excess obtained for all three caves between 15 2 and 16 6 match that of western mediterranean sourced waters 15 monthly d excess values suggest atlantic sourced air masses can reach the sites throughout the year but never dominate the rainfall composition the altitude effect was noted both in precipitation and in dripwater isotopic composition but with notably different 18 o 100 m gradients 0 33 and 0 11 respectively stable isotope variations of the dripwaters in all caves were attenuated in relation to the rainwater even those of the drip sites with fracture flow behaviour based on stable cave microclimate conditions relatively steady discharges and modern calcite apparently precipitated at or close to isotopic equilibrium with dripwater the two caves at lower altitudes show the greatest potential for future paleoclimate studies the cave at the highest altitude experiences large cave air temperature amplitudes 5 3 c and pronounced ventilation making the isotopic signal susceptible to kinetic fractionation which might preclude quantification of environmental changes but on the other hand it accentuates isotopic events making them easier to identify

late quaternary speleothem pollen in the british isles as with many terrestrial areas the british quaternary sequence is characterised by incomplete fragmentary records whose correlation is based on stratigraphic or biostratigraphic techniques due to the lack of radiometric ages beyond the 40 kyr limit of 14c dating speleothems secondary cave calcite deposits offer a significant advantage over many sources of palaeoenvironmental information they can be dated to a high precision and accuracy by uranium thorium 238u 230th thermal ionisation and inductively coupled plasma icp mass spectrometry in the time period back to 500 kyr they may also contain sufficient well preserved pollen representative of contemporary vegetation above the cave to allow palaeoenvironmental reconstruction this study adopts the novel approach of combining pollen and thermal ionisation mass spectrometric tims u th dating of british speleothems to produce well constrained palaeoenvironmental records we report for the first time precisely dated records of pollen assemblages from speleothems suggesting the presence of thermophilous arboreal species in phases previously considered to have been consistently cool or cold and devoid of trees copyright 2007 john wiley sons ltd

meteoric phreatic speleothems and the development of cave stratigraphy an example from tounj cave dinarides croatia abstract speleothems occurring in some caves of the carbonate dinarides line all channel surfaces and have been deposited from meteoric waters under phreatic conditions such phreatic speleothemic deposition modifies common experience l that meteoric phreatic conditions cause dissolutional widening of cave voids and 2 that speleothems imply vadose conditions the phreatic speleothems described here postdate an early polygenetic evolution of the cave voids and predate the last vadose stage they were likely produced during the late postglacial warming period when dissolved carbonate was amply supplied and when there was much water available for saturation of underground voids phreatic speleothems may be used as a tool for time correlation of internal deposits both within one cave and within a karst region they indicate an important stage in the history of the ground water regime of an area in general phreatic speleothems help in better understanding of the development of subterranean voids and related karst palaeokarst

early middle holocene relative sea level oscillation events recorded in a submerged speleothem from the yucatan peninsula mexico geomorphological and biological archives of relative sea level change in the western north atlantic caribbean region following the last glacial maximum have traditionally supported the hypothesis o

temperate skeletal carbonate sediments on scott shelf northwestren vancouver island canada abstract scott shelf 2000 km 2 centred at scott islands northwestern vancouver island is mainly shallower than 150 m topographically diversified and floored by bedrock outcrops and terrigenous lithic gravels and sands left stranded following the post glacial rise in sea level 13 000 yrs b p it lies in a zone of vigorous wind wave currents and strong tidal flows but is largely starved of modern terrigenous sediment as a consequence it is slowly accumulating a thin discontinuous blanket of clean skeletal carbonate sands and gravels admixed to varying degrees with the underlying terrigenous deposits principal skeletal contributors are infaunal bivalves on coarse sandy and gravelly substrates barnacles on low amplitude gravelly ridges bryozoans on bedrock outcrops and boulders and benthic foraminifera on fine sands in deep 100 m waters south of the scott islands living carbonate benthos are scattered and generally sparse occupying specific ecologic niches and the shelf wide rate of carbonate production is low skeletons are fragmented transported and mixed during storms and are concentrated within bedrock hollows and crevices and shallow depressions between gravel ridges where infaunal bivalves are abundant the carbonates are dominated by aragonite but otherwise the skeletal hashes are predominantly calcitic many grains and especially aragonitic ones are corroded and weakened by epilithic and endolithic bioerosion and probably also by marine and dissolution the most corroded shells have ages of only about 1000 yrs so that their preservation potential is low the character of scott shelf skeletal carbonate deposits reflects their temperate latitude cold water heritage

synchrotron radiation applications to past volcanism archived in speleothems an overview abstract precise dating and correlation of past key volcanic eruptions over a wide geographic area in archives of past climate variability is necessary to support a direct causality between volcanism and climate changes research has mostly focused on ice cores and varved sediments which capture a record of volcanic eruptions in geochemistry and the presence of tephra and criptotephra precisely dated cave carbonate deposits collectively known as speleothems are other valuable palaeoclimate archives and encode information on past volcanism in their sulphate concentration variability due to the physical characteristic of speleothems detection of sulphate concentration variability requires techniques capable of high spatial resolution very low limit of detection ppm to ppb and low background noise synchrotron radiation based sr micro x ray fluorescence xrf and x ray absorption near edge spectrometry prove to be one of the most effective techniques to detect short lived pulses of sulphate concentration increase which may be interpreted as being related to atmospheric load due to volcanic eruptions here we provide an overview of existing work as well as a novel interpretation of a sr xrf based sulphate series in an annually laminated stalagmite with robust chronology sulphate concentration peaks in the years 1815 1816 1844 and 1947 possibly coinciding with tambora krakatau and hekla eruptions it is concluded that sulphate concentration in speleothems expand the potential to correlate volcanic eruption events at a global scale

pseudogleyed loess derivates the most common soil parent materials in the pannonian region of croatia abstract loess derived sediments represent the most widespread soil parent materials in the pannonian region of croatia pseudogley as the most common soil type in this region developed mainly on such parent materials pseudogleys largely correlate with the wrb reference soil group of stagnosols on the general soil map of croatia at scale 1 50 000 gsm of croatia the distinction is made between pleistocene loams pl and loess as pseudogley parent materials the initial purpose of this research was to investigate if the criteria for this distinction were clear and consistent and if the terms used for labeling these parent materials were adequate hence we investigated parent materials of 18 pseudogleys across 6 different locations three on loess and three on pl in the pannonian region of croatia we analyzed their morphology including micromorphology of three representative parent materials particle size distribution total porosity ph and mineral assemblages by modal analysis of three representative parent materials following these analyses no systematic differences between the loess parent materials and the pl parent materials were found additionally it was concluded that due to significant geogenetic and or pedogenetic alterations of all studied parent materials none of them should be labeled simply as loess hence parent material at one location was labeled as leached loess derivate and parent materials at all other locations were labeled as pseudogleyed loess derivates both types of parent materials were described in detail and defined in addition the terminology and the classification of loess derived parent materials in general was proposed the analyzed pseudogleyed loess derivates were not completely uniform across the investigated locations primarily this was due to the polygenesis of loess reflected by differences in particle size distributions and compositions of light and heavy mineral fractions secondarily it was due to the 600 1100 mm map gradient along the study region reflected by differences in ph values and properties of redoximorphic features although pedogenesis of the investigated parent materials might have started already during the late glacial and have continued throughout the holocene at varying and overall decreasing rates their morphology indicates that pseudogleization and lessivage are still active processes which occur simultaneously in the analyzed parent materials and agree with the present climate

vertical crustal movements in the vicinity of the 1931 valentine texas earthquake deformation possibly related to an earthquake in texas has been revealed from analysis of precise leveling data collected by the national geodetic survey relative elevation changes deduced from first order leveling surveys conducted between 1910 and 1957 show that at least two areas in western texas near the epicenter of the 1931 valentine earthquake m 6 4 subsided relative to their surroundings apparent subsidence east of van horn texas is attributed primarily to the combined effects of groundwater withdrawal and topography related survey errors in contrast relative subsidence near valentine texas of 11 2 1 0 cm extending over a distance of about 20 km does not appear to be due to either near surface effects or leveling errors and thus may represent coseismic deformation of the valentine earthquake the large magnitude of the vertical movements indicated by the leveling data suggests significant dip slip movement on the inferred earthquake fault this is consistent with the cenozoic structure of the region which is characterized by basin and range morphology if the observed subsidence was caused by the 1931 earthquake the leveling data suggest that the epicenter for this event lies considerably closer to valentine than originally reported this new location is supported by a recent relocation for the valentine earthquake and by local intensity reports

a point sourced calciclastic submarine fan complex eocene anotz formation western pyrenees facies architecture evolution and controlling factors a complete transect of a fossil carbonate ramp slope has been reconstructed using outcrop data from the lower middle eocene anotz formation in the western pyrenees the anotz formation contains four calciclastic mostly bioclastic members encased within hemipelagic marl limestone alternations each calciclastic member representing a submarine fan system individual fans are composed of a gullied upper slope a leveed feeder channel a channelized lobe area an unconfined lobe zone and a peripheral lobe fringe that grades downcurrent into basinal deposits quantitative data on the dimensions and degree of lateral continuity and vertical connectivity of the anotz calciclastic fan elements are presented these data provide information for a better understanding of the intrinsic nature of calciclastic submarine fans and to model their reservoir potential the long term evolution of the anotz carbonate slope was generally progradational as evidenced by the four discrete episodes of calciclastic fan development the location of the fans was controlled by the synsedimentary tectonic activity of the pamplona fault which created a slope valley along which the reworked shallow water calciclastic sediments were funnelled in addition episodic basinward tilting of the shallow water carbonate ramp linked to the development of the south pyrenean foreland basin switched on and off the process of calciclastic resedimentation and determined the growth or abandonment of the fan systems

epeirogenic plate movements consideration is given to the kinematics of epeirogenic movements over the recent geologic past late pleistocene in a region for which there is an abundance of geological and geophysical information the continental shelf off the east coast of north america it is found that there has been a relative change in elevation of 140 m downward toward the northeast over this longitudinal distance of 3000 km during the past 18 000 years specifically miami has been elevated at a rate of 0 8 cm yr with respect to the scotian shelf continental margin the confirming data include the shelf break corrected for progradation reef building and glacio isostatic adjustment late pleistocene shores on the continental shelf earlier pleistocene unconformity surfaces dated geologic samples of known shallow water origin buried pleistocene channels and recent leveling analysis

stratal geometries facies and sea floor erosion in upper cretaceous chalk normandy france unusual lenticular stratal geometries and facies of the upper cretaceous chalk of coastal haute normandie france are described and interpreted thirteen facies within these chalks are described and illustrated on the basis of field thin section and sem investigations nannofossil mudstones nannofossil hardgrounds echinoderm wackestones and packstones echinoderm hardgrounds bryozoan mudstones and wackestones bryozoan hardgrounds bryozoan packstones and wackestones inoceramid wackestones inoceramid hardgrounds sponge hardgrounds marly chalks conglomeratic chalks and debris flow chalks these facies occur within lenticular bedded structures with both concave up and concave down geometries which have been previously interpreted as megaripples mud mounds or tectonic structures detailed examination of the structures and the associated facies indicates that the concave up geometries were formed from submarine erosion and redeposition in nw se longitudinal channels the concave down geometries developed between adjacent channels assessment of the regional and temporal setting indicates that the erosion occurred in the armorican cornubian straits of the anglo paris basin during sea level lowstands within these straits channelling is preferentially developed on the positive south western block to the lillebonne fecamp cotentin fault

volcanic ash fall events identified using principal component analysis of a high resolution speleothem trace element dataset large multivariate trace element datasets produced by la icp ms speleothem analysis can pose difficulties for analysis and interpretation processes acting on various timescales and magnitudes affect trace element concentrations and deconvolving the most important controls is often complex here principal component analysis pca is applied to identify the modes and timings of variation which best explain the overall variability in an exceptionally high resolution 10 m vertical resolution multivariate trace element record produced by la icp ms from a modern 1979 2001 belizean stalagmite with excellent age control principal component 1 pc1 in this dataset is defined by a weak correlation between multiple elements and may reflect non carbonate material incorporated within the speleothem elevated pc1 scores in atm 7 occur following regional volcanic eruptions with ash clouds extending over the cave site as demonstrated using nasa remote sensing data from the total ozone mapping spectrometer and hysplit trajectory modelling spikes in pc1 occur at the beginning of the wet season and this may reflect a seasonal flushing event that transports volcanogenic material through the karst and incorporates it within the speleothem our results suggest that pca can simplify exploration of large laser ablation datasets and that pca is a valuable tool for identifying the dominant controls on stalagmite trace element chemistry future studies should evaluate how transferable this technique is to other sites with different environmental conditions where volcanic ashfall has occurred this research potentially adds tephrochronology to the stalagmite dating toolkit or conversely opens the door to using stalagmites to identify previously unknown or uncertainly dated eruptions

climatology of cyclogenesis mechanisms in the mediterranean abstract a general climatology of the main mechanisms involved in mediterranean cyclogenesis is presented a diagnostic study of both composite means and case studies is performed to analyze processes occurring in different seasons and in different cyclogenetic regions within the same season it is shown that cyclones that developed over the three most active areas in winter the gulf of genoa the aegean sea and the black sea are essentially subsynoptic lows triggered by the major north atlantic synoptic systems being affected by local orography and or low level baroclinicity over the northern mediterranean coast it is also suggested that cyclones in two or all three of these regions often occur consecutively linked to the same synoptic system in spring and summer thermally induced lows become progressively more important despite the existence of other factors such as the atlas mountains contributing to lee cyclogenesis in northern africa or the extension of the asian monsoon into the eastern

late holocene climatic variability south of the alps as recorded by lake level fluctuations at lake ledro trentino italy a lake level record for the late holocene at lake ledro trentino northeastern italy is presented it is based on the sediment and pollen analysis of a 1 75 m high stratigraphic section observed on the southern shore site ledro i and a 3 2 m long sediment core taken from a littoral mire on the southeastern shore site ledro ii the chronology is derived from 15 radiocarbon dates and pollen stratigraphy the late holocene composite record established from these two sediment sequences gives evidence of centennial scale fluctuations with highstands at c 3400 2600 1700 1200 and 400 cal bp in agreement with various palaeohydro logical records established in central and northern italy as well as north of the alps in addition high lake level conditions at c 2000 cal bp may be the equivalent of stronger river discharge observed at the same time in central italy s rivers in agreement with the lake level record of accesa tuscany the ledro record also suggests a relatively complex palaeohydrological pattern for the period around 4000 cal bp on a millennial scale sediment hiatuses observed in the lower part of the ledro i sediment sequence indicate that except for a high stand occurring just after 7500 cal bp lower lake levels generally prevailed rather before c 4000 cal bp than afterwards finally the lake level data obtained at lake ledro indicate that the relative continuity of settlements in humid areas of northern italy during the bronze age in contrast to their general abandonment north of the alps between c 3450 and 3150 cal bp does not reflect different regional patterns of climatic and palaeohy drological conditions in contrast the rise in lake level dated to c 3400 cal bp at ledro appears to coincide with a worldwide climate reversal observed in both the hemispheres while palaeoenvironmental and archaeological data collected at lake ledro may suggest as a working hypothesis a relative emancipation of proto historic societies from climatic conditions

an introductory perspective on non tropical shelf carbonates abstract this brief account introduces the topic of non tropical shelf carbonate deposits both modern and ancient specific aspects of which are described and discussed in the 22 accompanying papers in this special issue of sedimentary geology non tropical shelves are loosely defined as lying poleward of the present limit of development of hermatypic coral reefs or beyond the mean annual surface water isotherm of about 20 c typically near 30 latitude most geoscientists have traditionally regarded shallow water carbonate formation as a low latitude phenomenon however wherever the rate and extent of terrigenous sediment dilution is small the potential exists for extensive deposits of skeletal carbonate to accumulate on shelves beyond the sub tropics the facies attributes of the modern non tropical carbonates are distinctive and contrast significantly with the structural lithological faunal floral mineralogical and diagenetic character of their tropical counterparts in the rock record non tropical limestones probably occur throughout the phanerozoic but generally remain to be identified and or interpreted as such they are presently described mainly from the ordovician permian and tertiary quaternary periods of major continental glaciations and accentuated latitudinal thermal gradients a uniformitarian approach to the recognition and interpretation of ancient shallow marine limestones requires acceptance of both tropical and non tropical carbonate facies models

orogenic evolution of the external dinarides in the ne adriatic region a model constrained by tectonostratigraphy of upper cretaceous to paleogene carbonates abstract mesozoic to cenozoic evolution of the central part of the adriatic plate external dinarides and adriatic foreland is still a matter of debate this is expressed by opposing paleogeographic models single carbonate platform adriatic or adriatic dinaridic versus two carbonate platforms adriatic and dinaridic separated by the inter platform budva cukali basin estimates of shortening during adria ne subduction that resulted in the development of the dinaric alps differ substantially the single platform model involves minor shortening achieved by folding and faulting along steep reverse faults the two platform model involves significant shortening achieved mainly by thrust stacking which resulted in almost complete underthrusting of the intervening basinal deposits analysis of upper cretaceous to paleogene stratigraphical data from both outcrops and boreholes allows regional correlation and the interpretation of major lithostratigraphic units as a result a few tectonostratigraphic units are recognized the tectonostratigraphy is used as a basis for a new model on the late mesozoic to cenozoic evolution of the region generally adriatic and dinaridic segments acted as major regional crustal entities of adria the upper portions of the sedimentary cover were differentially affected by progressive southwestward verging thin skinned deformations during the paleocene to eocene miocene the adriatic foreland stayed out of the deformations and is characterized predominantly by wrench and salt tectonics the regional tectonic map shows arcuate thrust fronts of the external dinarides they could be a consequence of both differential propagation of early orogenic thin skinned deformations over crustal fragments separated by transversal faults and or differential isostatic movements of the fragments the collision zone of the adriatic and dinaridic segments is characterized by late orogenic oligocene to miocene thick skinned compressional uplift exhumation related gravity gliding and still active escape tectonics wrenching these processes masked primary thin skinned deformations a significant amount of shortening within and between the thin skinned sedimentary covers is proposed therefore the question of the general paleogeography of the region and the original nw extent of the budva cukali basin ne adriatic trough remains open

an outer ramp to basin plain transect interacting pelagic and calciturbidite deposition in the eocene oligocene of the tuscan domain adria microplate italy abstract the interaction of ramps basin plains and turbidite systems on the scale of tens of km has been rarely observed in fossil examples deep marine eocene oligocene beds are exposed in the axial zone of the chianti mountains italy and compose a regionally continue stratigraphic succession known as the scaglia toscana formation the formation was deposited in the tuscan domain of the adria microplate this research aims at depicting its depositional architecture and evolution in the type area stratigraphic and sedimentologic analyses were performed on a ca 25 km long transect that includes depositional systems sectioned both in the down and along dip directions shaly carbonate deposits compose a complex of interacting ramps basin plains and turbidite floor fan systems ramp deposits accumulated above the lysocline and in oxic conditions basin plain beds were deposited below the lysocline and were subject to episodes of oxygen depletion turbidity flows fed elongate fan lobes characterized by poor channelisation the basin palaeogeography hampered the development of slope apron turbidite systems the eocene oligocene geodynamic setting of the tuscan domain was characterized by the evolution of a peripheral bulge and by the early structuring of a foredeep basin syn sedimentary tectonism acted a primary role in the basin scale arrangement however other mechanisms also contributed to the local facies distribution including the disposition of sediment source areas and intrabasinal confinement morphologies as well as relative oscillations of the depositional surface with respect to the lysocline and oxycline

pollen from accurately dated speleothems supports alpine glacier low stands during the early holocene deciphering pollen assemblages from alpine speleothems holds potential to provide unique information about past vegetation in rapidly changing environments here we reconstruct subsurface aerosol transport at milchbach cave switzerland 1840 m asl based on the pollen content of two holocene stalagmites we demonstrate that pollen is chiefly associated with bacterially mediated calcite fabrics typical of a well ventilated cave system in contrast pollen is absent from columnar calcite fabrics confirming that hydrological transport is not a significant process for the incorporation of pollen into speleothems at milchbach cave our results support significant changes in the subsurface ventilation regime which can be associated with the waxing and waning of upper grindelwald glacier pollen assemblages obtained from six carbonate sub samples attest the presence of a mixed deciduous forest in the grindelwald valley during the early and middle holocene in agreement with coeval regional pollen records this study demonstrates that even small amounts of calcite 0 3 2 8 cm3 are capable of delivering pollen spectra representative of the original vegetation if sufficiently elevated deposition fluxes are provided

a numerical study of the climate response to lowered mediterranean sea level during the messinian salinity crisis abstract roughly six million years ago tectonic movements isolated the mediterranean sea ms from the atlantic ocean an event known as the messinian salinity crisis msc subsequent evaporative drawdown of the ms resulted in a subaerial depression with a depth between 1500 and 2500 m in this study five simulations are run using the national center for atmospheric research ncar community atmosphere model version 3 cam3 configured with the slab ocean model three simulations have been performed to test the climate impacts to desiccation and to changing the ms base level in this study the ms base level is reduced 750 m in the half land simulation hl and 1500 m in the lowered sea ls and lowered land ll simulations the hl and ll simulations differ from the ls in that the surface is converted to land representing the complete desiccation of the ms the substantial ms depression generates planetary scale atmospheric waves responsible for significant climate effects throughout the northern hemisphere a notable deepening of the aleutian low and a significant equatorward shift in the atlantic jet stream are evident in djf vertical ascent at the northern margin of the ms results in a 1 5 2 5 mm day 1 precipitation anomaly in the ls run over the alps consistent with proxy data annual mean area averaged ms evaporation is slightly higher than control conditions except when salinity is a substantial barrier to evaporation our results suggest that a partially filled basin cannot exist in equilibrium and the ms must either be partly connected to the atlantic ocean or completely desiccated base level lowering which alters the water budget must be taken into account when considering the freshwater budget during the msc

submarine lobes and feeder channels of redeposited temperate carbonate and mixed siliciclastic carbonate platform deposits vera basin almeria southern spain temperate carbonates and mixed siliciclastics carbonates of upper tortonian age were deposited on a narrow platform along the southeastern margin of the sierra de los filabres on the western side of the vera basin the temperate carbonates were unlithified or were only weakly lithified on the seafloor and so were easily prone to synsedimentary removal part of the shelf sediments were eroded reworked and redeposited in submarine lobes up to 40 m thick and 1 km wide the lobes consist of turbiditic carbonates calcarenites and calcirudites and mixed siliciclastics carbonates which contain up to 30 siliciclasts derived from the sierra de los filabres to the northwest and abundant bioclasts of coralline algae bivalves and bryozoans in the inner platform the feeder channels of the lobes cross cut beach and shoal deposits and are filled by strings of debris flow conglomerates up to 3 m thick and a few metres wide these channels presumably developed as the continuation of river courses entering the sea further towards the outer platform they pass into large channels up to several hundred metres wide and 20 m deep steeply cutting into the horizontally bedded strata of the platform significant quantities of platform sediment were removed by erosion during their excavation once abandoned they were filled by new platform sediments further towards the basin the channels associated with the lobes exhibit lateral accretion and internal cut and fill structures and are intercalated between hemipelagic deposits the channel filling sediments are in this latter case coarse grained carbonates and mixed siliciclastics carbonates lobe development concentrated first at cortijo grande on the western side of the

from platform top to adjacent deep sea new source to sink insights into carbonate sediment production and transfer in the sw indian ocean glorieuses archipelago abstract over the past ten years a huge amount of source to sink studies have aimed to unravel the tectonic climatic and other processes that shape the landscape from mountains to the deep ocean interestingly these studies have been mainly dedicated to siliciclastic or mixed systems for which the connection between drainage basins continental shelves slope and basin environments are often well constrained here we present a study focusing on a source to sink study dedicated to a pure carbonate system located in the sw indian ocean glorieuses archipelago extensive field sampling and geophysical acquisition across the carbonate platform have allowed us to estimate the composition the lateral variability and volumes of neritic sands deposited on the platform top additional seismic and bathymetric surveys across the platform interior illustrate the presence of plurimetric sandy bodies deposited along the leeward platform edge corresponding to the export of carbonate sediments from the platform top toward the platform edge under the influence of dominant currents and wind driven processes high resolution seismic bathymetric data and sediment cores acquired along the leeward slope and basin adjacent to the carbonate platform highlight the presence of channel levee complexes and turbiditic lobes which have accumulated on the seafloor on top of a 250 m thick sedimentary basin at 2000 3400 m water depth our study points out that carbonate sands and aragonitic mud produced on the platform top during the holocene have been shed to the adjacent basin we also demonstrate that this routing system was active at least throughout the last three glacial interglacial cycles this study has important consequences for our understanding of carbonate sedimentation processes occurring in the vicinity of isolated carbonate platforms 1 it highlights the role of oceanographic conditions in the distribution of sediment on a platform top and its export along the platform edge and the adjacent basin 2 it contributes to quantify the productivity of a carbonate platform as well as its sediment storage capacity 3 a first estimate of a carbonate source to sink system is proposed demonstrating that 0 57 km3 of sediments have been produced during the holocene 0 3 km3 being presently stored on the platform and the remaining having been exported to the deep basin

architecture and evolution of calciclastic marginal slope fans of the ordovician carbonate platform in the yijianfang outcrop of the bachu area west tarim basin the ordovician carbonate platform at the yijianfang outcrop of the bachu uplift region in the western tarim basin contains four types of genetic facies associations developed in the calciclastic slope fan depositional system an olistostrome zone fan channels lobes and a marginal slope the olistostrome zone is characterized by olistoliths and slump fans whereas the fan channels and lobes are further divided into proximal and distal facies the marginal slope deposits constitute the background sedimentation in which the calciclastic slope fans are intercalated from proximal to distal parts of the fan channels and lobes their scale gradually becomes smaller and the size and sorting of grains become finer and better respectively analysis of the stratigraphic framework indicates that the fans formed in the lower strata of the upper ordovician lianglitage formation in four high frequency sequences i e pss1 pss4 field paleocurrent measurements indicate northeast southwest depositional strike for the early platform margin of the lianglitage formation sediments in the calciclastic slope fans were derived from the platform margin and evolution of the calciclastic slope fans was generally progradational from pss1 to pss2 and then continuously retrogradational from pss2 to pss4 the calciclastic slope fans in the outcrop area are not reservoir prone rocks but interpretation on these fans can provide useful information about potential hydrocarbon reservoirs along the platform margin the p wave velocity s wave velocity and density variations in each genetic facies may be used to identify the subsurface calciclastic slope fan depositional system

foramol carbonate shelves as depositional site and source area recent and ancient examples from the mediterranean region abstract in recent environments only limited carbonate depositional areas are dominated by coral reefs such platforms frequently develop rimmed margins and are characterized by chlorozoan facies with large contributions of nonskeletal grains they are practically limited to warm tropical seas in temperate seas as well as anomalous tropical zones large areas of the middle outer shelf are covered by skeletal debris with variable amounts of mollusks foraminifers coralline algae bryozoans etc foramol facies apart from the skeletal fragments derived from the shallow inner shelf and the contribution from local endobiota and epibiota the source of the bioclastic sediments may be found in limited and scattered areas supporting active carbonate producing assemblages fossil counterparts of similar deposits are present in the mediterranean region e g spain italy malta libya locally showing good reservoir properties examples are described from the miocene of the southern apennines italy where a variety rich in encrusting coralline algae is present as well as from the upper cretaceous of the southern apennines and northwest sardinia italy where scattered rudistid buildups are associated with bioclastic sediments rich in coralline algae and bryozoans

late pleistocene holocene sea level rise and the pattern of coastal karst inundation records from submerged speleothems along the eastern adriatic coast croatia in order to reconstruct the late pleistocene holocene sea level rise along the eastern adriatic coast eight speleothems were collected from three submerged caves along the croatian coast from depths of 38 5 to 17 m the marine biogenic overgrowth layer and the youngest and the oldest parts of the speleothems were dated by the 14c method their stable isotope 13c 12c and 18o 16o contents were also measured from the measured 14c activity of the marine overgrowth and using the model of alessio et al 1992 risultati preliminari relativi alla datazione di speleotemi sommersi nelle fasce costiere del tirreno centrale giornale di geologia ser 3 54 2 165 193 the start of overgrowth i e the time of flooding by seawater was determined to be 10 185 cal bp at 36 m 9160 cal bp at 34 m and 7920 cal bp at 23 m our results partially match the sea level curves reconstructed for adjacent areas tyrrhenian coast and french mediterranean coast however the start of the marine overgrowth on speleothems in pit caves indicates strong dependence on the steepness of the terrain on steep extensively karstified coasts marine overgrowths on speleothems coincided with the submersion of the speleothems due to the relatively short distance between the pit and the open sea and fast penetration of seawater into the pit in contrast marine overgrowths on speleothems in pits in the flat terrains occurred later because speleothem growth ceased due to flooding with fresh groundwater later the fresh water was replaced by seawater due to the greater distance of the inland pits to the former coast

the cenozoic graben system of sardinia italy geodynamic evolution from new seismic and field data abstract a tectono sedimentary scenario for the southern sardinia italy cenozoic graben system is proposed using field observations and the interpretation of onshore and offshore seismic profiles the major structural events are tied to the general geodynamic evolution of the western central mediterranean thus the extensional late oligocene aquitanian event is a consequence of an apenninic westward subduction process associated with a volcanic arc 29 30 to 15 16 my which is particularly well exposed in sardinia deposition of sub aerial clastics was followed by transgression of the rift depression at the beginning of the aquitanian subduction terminated at the opening of the oceanic provencal basin and the rotation of sardinia corsica during burdigalian time 20 21 to 15 16 my the messinian compressional event ne sw oriented documented from microtectonic data strongly affected the oligo miocene basin the superimposed plio quaternary campidano graben which is probably related to the formation of the tyrrhenian basin contains more than 600 m of syntectonic deposits a change in polarity of the master faults bounding the oligo miocene rift created a central horst type twist zone separating two depocenters in the oristano and cagliari regions emplacement of large volcanic bodies and inversion of the basin during the messinian in cagliari area has reduced the areas with potential for hydrocarbon exploration the two remaining prospective zones are the oristano sub basin and the offshore south of cagliari where burial of lower miocene marine organic matter may have been sufficient to generate hydrocarbons potential reservoirs could be pre rift mesozoic or eocene strata but are mainly excellent miocene sands derived from erosion of the granitic basement in tilted blocks

non seagrass meadow sedimentary facies of the pontinian islands tyrrhenian sea a modern example of mixed carbonate siliciclastic sedimentation abstract the soft bottom of the mediterranean continental shelf is characterized by a heterozoan skeletal assemblage sensu james n p 1997 the cool water carbonate depositional realm in james n p clarke j eds cool water carbonates spec publ soc sediment geol vol 56 pp 1 20 although the contemporary presence of terrigenous and skeletal carbonate sediments has been well established tortora p 1996 depositional and erosional coastal processes during the last postglacial sea level rise an example from the central tyrrhenian continental shelf italy j sed res 66 391 405 fornos j j ahr w m 1997 temperate carbonates on a modern low energy isolated ramp the balearic platform spain journal of sedimentary research 67 364 373 fornos j j ahr w m 2006 present day temperate carbonate sedimentation on the balearic platform western mediterranean compositional and textural variation along a low energy isolated ramp in pedley h m carannante g eds 2006 cool water carbonates depositional systems and palaeoenvironmental controls geological society london special publications 255 pp 121 135 the interactions between carbonate and terrigenous siliciclastic sedimentation has not been documented well enough a total of 33 surface sediment samples from the pontinian shelf tyrrhenian sea central mediterranean have been analysed sampling stations range from 15 to 250 mwd meter water depth and are located along five transects ponzaw ponzanw ponza ne ponza e zannone plus four samples collected around palmarola island sectors colonized by seagrass meadows have not been sampled a total of 6 sedimentary facies f and 10 microfacies mf have been recognized by using component analyses grain size percentage sorting carbonate content and authigenic mineralization rate these facies and microfacies represent the pontian islands shelf sedimentation in the interval between the upper infralittoral and the epibathyal zones that represent shelf break and upper slope sedimentation the maerl facies f4a b mf4a b and the skeletal sands f2a b mf2a1 mf2a2 mf2b fall within the circalittoral zone the circalittoral zone in the water depth interval between 82 m and 112 m display relict facies f6 mf6 finally facies f5 siliciclastic sands includes subfacies f5b mf5b located in the circalittoral zone at depths of 49 to 101 mwd and restricted to the western and eastern sectors of ponza and subfacies f5a in the upper infralittoral zone 15 mwd 25 mwd where erosional processes prevail carbonate content analyses indicate that maximum carbonate production on the pontinian shelf took place in the 60 80 mwd interval facies f4 maerl represents the environment characterized by the highest carbonate production rates in the pontian area siliciclastic carbonate mixing took place in the infralittoral zone and in the lower circalittoral zone in the infralittoral zone erosional processes on the rocky shoreline produced lithoclasts and vulcanoclastic deposits that were reworked by wave induced near shore currents in the lower circalittoral zone the prolific production by photic biota red algae ends while skeletal remains of the aphotic environment mixes with planktonic sediments characterized by low carbonate values sand 63 m 2 mm is the dominant grain size class however gravel dominated facies f4 maerl are present in water depths 50 to 112 mwd which are significantly below the storm wave base glauconite mineralization appears on the pontinian shelf from 50 mwd and increases in abundance along the deeper bathymetries the compositional characteristics of relict facies f6 shows the concurrence of biota assemblages of the infralittoral and circalittoral zones likely representing the record of the last holocene transgressive event 18 ky and expressed by the overlapping of components of different environments

palaeo climate reconstruction from stable isotope variations in speleothems a review abstract speleothems are now regarded as valuable archives of climatic conditions on the continents offering a number of advantages relative to other continental climate proxy recorders such as lake sediments and peat cores they are ideal materials for precise u series dating yielding ages in calendar years thereby circumventing the radiocarbon calibration problems associated with most other continental records stable isotope studies in speleothems have shifted away from attempting to provide palaeo temperature reconstructions to the attainable goal of providing precise estimates for the timing and duration of major o isotope defined climatic events characterised by high signal to noise ratios e g glacial interglacial transitions dansgaard oeschger oscillations the 8200 year event unlike the marine records speleothem data sets are not tuned and their independent chronology offers opportunities to critically assess leads and lags in the climate system that in turn can provide important insights into forcing and feedback mechanisms improved procedures for the extraction and measurement of stable isotope ratios in fluid inclusions trapped in speleothems are likely to provide in the near future a much enhanced basis for the quantitative interpretation of o isotope ratios in speleothem calcite the latter developments open up once again the tantalising prospect of palaeo temperature estimates but more importantly perhaps provide a direct test for a new generation of general circulation models whose hydrological cycles will incorporate the water isotopes the literature is reviewed briefly to provide for the reader a sense of the current state of the art and to provide some pointers for future research directions

evolution of the adriatic carbonate platform palaeogeography main events and depositional dynamics abstract the adriatic carbonate platform adcp is one of the largest mesozoic carbonate platforms of the perimediterranean region its deposits comprise a major part of the entire carbonate succession of the croatian karst external or outer dinarides which is very thick in places more than 8000 m and ranges in age from the middle permian or even upper carboniferous to the eocene however only deposits ranging from the top of the lower jurassic toarcian to the top of the cretaceous can be attributed to the adcp defined as an isolated palaeogeographical entity although the entire carbonate succession of the karst dinarides was deposited within carbonate platform environments there were different types of carbonate platforms located in different palaeogeographical settings carboniferous to middle triassic mixed siliciclastic carbonate deposits were accumulated along the gondwanian margin on a spacious epeiric carbonate platform after tectonic activity culminating by regional middle triassic volcanism recorded throughout adria the african promontory a huge isolated carbonate southern tethyan megaplatform abbreviated as stm was formed with the area of the future adcp located in its inner part tectonic disintegration of the megaplatform during the middle to late early jurassic resulted in the establishment of several carbonate platforms including the adriatic apenninic and apulian separated by newly drowned deeper marine areas including the adriatic basin as a connection between the ionian and belluno basins lagonero basin and the area of the slovenian and bosnian troughs the adcp was characterised by predominantly shallow marine deposition although short or long periods of emergence were numerous as a consequence of the interaction of synsedimentary tectonics and eustatic changes also several events of temporary platform drowning were recorded especially in the late cretaceous when synsedimentary tectonics became stronger leading up to the final disintegration of the adcp the thickness of deposits formed during the 125 my of the adcp s existence is variable between 3500 and 5000 m the end of adcp deposition was marked by regional emergence between the cretaceous and the palaeogene deposition during the palaeogene was mainly controlled by intense synsedimentary tectonic deformation of the former platform area some carbonates mostly eocene in age were deposited on irregular ramp type carbonate platforms surrounding newly formed flysch basins and the final uplift of the dinarides reached its maximum in the oligocene miocene the adriatic carbonate platform represents a part although a relatively large and well preserved one of the broader shallow water carbonate platform that extended from ne italy to turkey although its continuity is somewhat debatable in the area near albanian greece boundary this large carbonate body which was deformed mostly in the cenozoic including a significant reduction of its width needs a specific name and the central mediterranean carbonate platform is proposed abbreviated to cmcp although the local names such as adcp for its nw part should be kept to enable easier communication and to facilitate description of local differences in platform evolution

tectonic constraints on the late pleistocene holocene relative sea level change along the north eastern adriatic coast croatia abstract in spite of very favourable coastal features late pleistocene holocene relative sea level changes along the eastern adriatic coast are still not completely resolved mostly due to the intensive and complicated regional and local neotectonics we gathered current knowledge that generally presents the north adriatic area as subsiding one and proposed a reconstruction in new light of possible very slow local uplift average rate of 0 1 0 25 mm a for last 80 ka which is supported by well dated submerged speleothems and tectonic reconstruction in addition such a scenario supports also the formation of tidal notches that are common in the north adriatic region but not yet entirely understood however according to the latest mediterranean data on sea level during the marine isotope stage mis 5 1 being at 1 m 80 ka ago we do not dismiss the possibility of subsidence which would have been 0 18 0 23 mm a on average for the last 80 ka but notch formation under such condition would not have been realistic apparently the position of the north eastern adriatic coast on a convergence area requires extensive palaeoenvironmental studies including structural lithostratigraphical palaeontological archaeological and radiometric data and application of isostatic modelling

hydrology of cave drip waters at varying bedrock depths from a karst system in southeastern australia the study of how cave drip water discharge responds to recharge events is fundamental to evaluating the potential of actively forming speleothems as high resolution climate archives most previous research has focused on caves of the northern hemisphere middle latitudes where recharge is strongly seasonal few studies have explored drip water behaviour from regions where the expected seasonal rainfall pattern is significantly perturbed on an irregular basis by changing regional atmospheric circulation patterns here we report the results of a 4 year study of cave drip water climate relationships from two caves in eastern australia the discharge of 10 drip sites located beneath bedrock thicknesses of 12 22 and 45 m was monitored either continuously using automated infrared sensors or at discrete approximately monthly intervals and compared with local rainfall and water balance data the study period traversed two major droughts including the severe 2002 2003 el nino drips at 12 and 22 m depths responded almost simultaneously to individual recharge events although the time lag between individual events varied according to the volume of recharge and pre event storage overall a steady decline in discharge is evident through the moisture deficit period with increased flows through phases of positive water balance speleothems growing at these and similar shallow chamber sites have potential for reconstructing palaeo rainfall trends at high resolution although the highly variable nature of year to year recharge would make it difficult to obtain data on a calendrical time scale drips at 45 m depth did not respond consistently to individual recharge events and displayed hydrological behaviour markedly dissimilar to one another and to the near surface drip sites indicating great complexity in karst architecture and the absence of fissure flow although speleothems at this depth may well preserve information on longer term rainfall trends their potential to encode a palaeo rainfall variability signal at interannual resolution is poor copyright 2007 john wiley sons ltd

cambrian to holocene structural and burial history of nashville dome about 14 000 ft 4 270 m of strata covered basement over the present crest of the nashville dome by the end of the paleozoic calculated by estimating the geothermal gradient and using temperatures of veins in stones river group and knox dolomite at least 7 500 ft 2 290 m of post devonian strata have been removed by subsequent erosion estimates of other erosional episodes include 350 ft 107 m of upper knox during the middle ordovician and 500 ft 152 m of devonian ordovician during the late devonian mesozoic to holocene uplift was at least 6 350 ft 1 940 m 1 500 ft or 460 m 25 of which occurred in the latest 100 m y and 450 ft or 140 m 7 during the latest 2 m y a rate ranging from about 15 ft m y 4 6 m m y for the longer term to over 225 ft y 70 m m y in the pleistocene to holocene earliest structure of the area was a series of elongate basins probably rifts synchronous with reelfoot rift to the west uplifts trending n10 e moved about 40 mi 65 km westward during the middle ordovician these may relate to similar trending and moving appalachian orogenic events a change to uplifts trending n50 e parallel to strikes of appalachian thrusts occurred in the late ordovician and continued to the devonian this may reflect a similar late ordovician change in the orientation of appalachian tectonism in the interval from post mississippian to late cretaceous the dome curved westward to join the pascola arch in response to ouachita activity

holocene environmental record from lake sediments in the bokanjacko blato karst polje dalmatia croatia abstract the bokanjacko blato karst polje field is a typical depression along the eastern adriatic coast that is filled with lake sediments this large scale structure is also an hydrologically important region as wells in southern part of the karst polje comprise the water supply for surrounding towns and villages the evolution of this polje however remains poorly understood a 7 8 m long sediment core from the south eastern part of the karst polje is utilized in this study to enable a multiproxy approach to the reconstruction of depositional processes that have occurred over the last 10 3 ka cal bp the sedimentological mineralogical and geochemical characteristics as well as palynological analyses of this core indicate that the whole sediment sequence consists of lake sediments alongside a variable amount of carbonates and silicates the lake existed for approximately 10 300 years before it was drained for agricultural purposes in the 1960s depositional changes are also evident throughout the core between 10 3 and 4 2 ka cal bp a higher values of magnetic susceptibility ms and concentrations of lithogenic elements indicate increased erosion and input of material from the catchment and therefore wetter climatic condition deposition of siliciclastic detrital material gradually decreased from 4 2 ka cal bp onwards replaced by carbonate sedimentation alongside minimal input of the former the carbonate based sandy silt sedimentation remains until hydromelioration of the depression the results of this study show that the lake level gradually increased between 4 2 and 2 9 ka cal bp evidenced by a higher carbonate content and a lower proportion of detrital material reaching a maximum between 2 9 and 1 6 ka cal bp data also show that at 1 6 ka cal bp the lake level was likely lowered due to higher nutrient content including sulfur s and phosphorus p as well as organic compound levels prior to human intervention and hydromelioration for agriculture high concentrations of the nutrient elements lead pb copper cu and zinc zn in the upper 40 cm of this sequence are indicative of the influence of agricultural activities across the karst polje as well as anthropogenic atmospheric pollution geochemical and sedimentological proxies illustrate centennial scale variability in carbonate deposition and erosional runoff processes comparable with the natural climatic and anthropogenic factors that are known to influence the evolution of holocene karst poljes across the central mediterranean

chlorozoan versus foramol lithofacies in upper cretaceous rudist limestones abstract the study of upper cretaceous limestones of the nurra region northwestern sardinia italy that crop out with open shelf rudist rich deposits has shown that during the early senonian coniacian santonian interval sediments characterized by assemblages dominated by molluscs with variable amounts of red algae bryozoa and echinoids replaced sediments including hermatypic corals green algae and variable amounts of non skeletal grains these latter components were largely dominant in the previous carbonate shelf contexts of the nurra during jurassic early cretaceous times becoming less numerous until they disappeared in the transgressive deposits that followed the tectonically induced middle cretaceous emersion phase a rhodalgal association typical of anomalous tropical areas or transitional ones has been recognized in the replacing limestones that may be more generically considered foramol type deposits this seems to document conditions of stress in the waters impinging on the nurra carbonate platform during the coniacian santonian transition the observation that in the late cretaceous a similar evolutionary trend seems to have characterized many shallow neritic successions from many different areas leads us to hypothesize more general causes of stress e g induced upwellings on the marginal sectors of the shelves increased oceanic overturns and hyperproductivity due to terrestrial runoff on post emersive transgressed substrata peculiar oceanic conditions were able to create depositional contexts that were considerably changed with respect to the previous ones such that the more opportunistic forms of the foramol assemblages flourished the change in dominant assemblages resulted in a different organization of the sediment as a response to the different producing communities the resulting temperate type carbonate shelves were characterized by a low growth potentiality essentially due to a higher dispersion rate and this could have facilitated their drowning

heterozoan carbonate deposition on a steep basement escarpment late miocene almeria south east spain heterozoan temperate water carbonates mixed with varying amounts of terrigenous grains and muddy matrix azagador limestone accumulated on and at the toe of an inherited escarpment during the late tortonian early messinian late miocene at the western margin of the almeria nijar basin in south east spain the escarpment was the eastern end of an uplifting antiform created by compressive folding of triassic rocks of the betic basement channelized coralline algal bryozoan rudstone to coarse grained packstone together with matrix supported conglomerate are the dominant lithofacies in the higher outcrops comprising the deposits on the slope these sediments mainly fill small canyon shaped half graben depressions formed by normal faults active before during and after carbonate sedimentation roughly bedded and roughly laminated coralline algal bryozoan rudstone to coarse grained packstone are the main lithofacies forming an apron of four small kilometre scale lobes at the toe of the south eastern side of the escarpment almeria area channelized and roughly bedded coralline algal bryozoan rudstone to coarse grained packstone conglomerates packstone and sandy silt accumulated in a small channel lobe system at the toe of the north eastern side of the escarpment las balsas area carbonate particles and terrigenous grains were sourced from shallow water settings and displaced downslope by sediment density flows that preferentially followed the canyon shaped depressions roughly laminated rudstone to packstone formed by grain flows on the initially very steep slope whereas the rest of the carbonate lithofacies were deposited by high density turbidite currents the steep escarpment and related break in slope at the toe favoured hydraulic jumps and the subsequent deposition of coarse grained low transport efficiency skeletal dominated sediment in the apron lobes accelerated uplift of the basement caused a relative sea level fall resulting in the formation of outer ramp carbonates on the apron lobes which were in turn overlain by lower messinian coral reefs this is the first known example of a base of slope apron within temperate water carbonate systems this article is protected by copyright all rights reserved

diatom responses to holocene environmental changes in a karstic lake vrana in dalmatia croatia abstract the 11 m sediment core of karstic lake vrana located at the dalmatian coast of eastern adriatic croatia was investigated through the analyses of diatoms the diatoms exhibited six marked changes in diatom zones dz with included water sediment interface as the record of environmental changes detected by marine and other terrestrial palaeoclimate records the diatoms recorded at the deepest sediments were interpreted to represent pleistocene holocene transition the dated holocene history is top 810 cm core section ca 8 1 cal kyr bp to the present the first zone record 1101 1050 cm was interpreted as alkaline oligo mesotrophic oxic lentic ecosystem of the karstic flooding plain based on the dominance of epithemia adnata enhanced bioproductivity of the shallow and unstable environment was noticed in the second diatom zone 1050 815 cm which was interpreted as the beginning of the holocene and it was divided into 4 subzones because of rapid environmental fluctuations a warmer period of temperate climate with a pluvial phase initiated development of the oligo mesosaprobic shallow lake in the early holocene the expansion of the macrophytes and higher cyanobacteria production that caused acidification and oxygen depletion at the lake bottom was determined in the mid holocene 810 713 cm 8 1 7 1 cal kyr bp mid holocene 8 1 4 7 cal kyr bp is marked by oligohalobic freshwater epithemia argus characteristic for alkaline water high cyanobacteria production was determined as a consequence of algal production that induced anoxic conditions in the lake bottom sediments from the warmer period till today the initial marine influx through the permeable karst underground was observed in the sediment record from ca 5 cal kyr bp the discovered marine influence on the lake indicating brackish water conditions related to the holocene sea level high stand the sea intrusion had different intensities through time and is still observed today in the seasonal fluctuation of lake water salinity the late holocene 2 7 cal kyr bp to the present sediment record is characterized with the strongest marine influxes and highest biodiversity of the mesosaprobic lake major changes in the water sediment interface of very shallow karstic lake were caused by anthropogenic agricultural activity in vrana diatom compositions of lake vrana indicate that they are sensitive to both paleoclimatic changes freshwater influx and sea level rise marine intrusion through permeable karst

the base of slope carbonate breccia system of ceuse tithonian s e france occurrence of progradational stratification in the head plug of coarse granular flow deposits abstract once interpreted as a deep water canyon infilling and later as some kind of tempestite deposit the tithonian breccias of ceuse are here reinterpreted as a small lobe deposit emplaced at the mouth of a gully cutting into a slope between two deep water terraces in the eastern part of the subalpine basin the breccias belong to two basic categories mostly grain supported and occasionally mud supported spectacular large scale oblique geometries apparent lateral accretions are observed in the grain supported breccias both within the infilling of the lower feeder channel and in the updip part of the lobe detailed analyses of these geometries show that they correspond to progradational features both laterally and in a more distal position on the lobe these progradational bodies evolve into a pile of unsorted massive breccias sometimes showing a crude even stratification we thus propose a depositional model for the grain supported breccias linking the two facies as follows the deposition of a gravity flow begins at the toe of slope mouth of the tributary gully by a progradational head which evolves downslope and laterally to a splay of massive or crudely stratified breccia the internal oblique stratification flattens distally over a distance of a few kilometres elementary beds pile up in morphological compensation to build the 100 m thick breccia body of ceuse because the breccias are derived from the gravity reworking of deep water nodular carbonates there is no sand sized material available in the depositional system or only a little probably produced through an erosive clast grain diminution process during transport this explains why the thick breccia beds pass quickly eastward to thin bedded mud turbidites

submerged caves of croatia distribution classification and origin presently 235 submerged caves and pits have been recorded along the croatian coast and islands partly or completely submerged by sea water contrary to the inland situation recorded submerged features are predominantly horizontal 60 though there are indications that the real situation is similar to that of the continental part where 69 are vertical pits completely marine conditions are established in 126 caves and the rest are anchihaline caves and submarine springs speleothems are found in more than 140 caves by their origin the investigated caves are all continental features formed in mesozoic and palaeogene carbonates subsequently submerged owing to sea transgression due to the relatively low wave energy rapid sea level rise and maturity of the host rock they do not fit into concepts of a sea cave or a flank margin cave development but they fulfil several conditions for being the blue holes since the term blue hole is mainly associated with the bahamian karst our attempt is only to show the possible similarities with no intention of ascribing that term to the croatian caves beside karstological issues croatian submerged caves are unique environmental archaeological and tourism assets

calciclastic submarine fans an integrated overview abstract calciclastic submarine fans are rare in the stratigraphic record and no bona fide present day analogue has been described to date possibly because of that and although calciclastic submarine fans have long intrigued deep water carbonate sedimentologists they have largely been overlooked by the academic and industrial communities to fill this gap we have compiled and critically reviewed the existing sedimentological literature on calciclastic submarine fans thus offering an updated view of this type of carbonate slope sedimentary system calciclastic submarine fans range in length from just a few to more than 100 km three different types can be distinguished 1 coarse grained small sized most calciclastic submarine fans were formed on low angle slopes and were sourced from distally steepened carbonate ramps subjected to high energy currents under these conditions shallow water loose grainy sediments were transferred to the ramp slope and eventually funnelled into the submarine fan by sediment gravity flows these conditions seem to have been more easily met on leeward margins in which the formation of reefs was hampered by cool waters nutrient enrichment or oligophoty another circumstance that contributes to the transfer of shallow water sediments to the distal ramp slope is a low sea level forcing the carbonate factory closer to the slope break and destabilizing sediments by increased pore water pressure however the most important factor controlling the development of calciclastic submarine fans was the existence of an efficient funnelling mechanism forcing sediment gravity flows to merge downslope and build up a point sourced sedimentary accumulation in most cases this occurred through a major slope depression associated with tectonic structures an inherited topography or large scale mass failures

sea level change during mis 5a based on submerged speleothems from the eastern adriatic sea croatia abstract two stalagmites were collected from below sea level in u vode pit on the krk island eastern adriatic sea at elevations of 14 5 and 18 8 m they exhibit a growth history indicating a double high sea level stand during marine isotope stage mis 5a 87 77 ka thin layers of halite and gypsum were found to be associated with hiatuses in speleothem growth probably caused by seawater inundation during sea level highstands these mineral deposits are likely to have been precipitated during marine regression phases under evaporitic conditions we constrain the age of the speleothem growth below and above growth hiatuses and hence timing of possible marine incursions using multi collector inductively coupled plasma mass spectrometry mc icpms u th techniques age estimates indicate that during mis 5a relative sea level elevations were greater than 14 5 m from 87 to 82 ka and 18 8 m from 77 to 64 ka and constrained to be lower than 18 8 m from 93 to 90 ka 82 to 77 ka and 64 to 54 ka assuming no tectonic adjustment however present speleothem depths could indicate long term regional tectonics

genesis of limestone megabreccias and their significance in carbonate sequence stratigraphic models a review a re appraisal of the factors controlling the deposition of carbonate megabreccias and their sequence stratigraphic significance is presented based on an examination of the mechanisms for instigating carbonate seafloor slope instability and a review of the depositional settings of these distinctive rock deposits limestone megabreccias have classically been interpreted as formed by the catastrophic collapse of high angle metastable oversteepened carbonate platform margins however a review of megabreccia occurrence shows that these deposits formed on a broad range of carbonate slope angles and that metastable oversteepened slopes are not necessary for their genesis a re evaluation constructed from first principles of mechanisms promoting submarine gravitational instability indicates that pore water overpressure of confined aquifer horizons beneath the seafloor rather than slope oversteepening is the critical control on megabreccia deposition catastrophic release of overpressure may initiate gravitational instability of previously kinematically stable slopes the relative importance of endogenic processes intrinsically linked to the depositional system and exogenic processes operating independently in generating megabreccias is assessed two particularly important mechanisms in generating megabreccias are endogenic processes causing overpressure at discrete hydrologically confined horizons beneath the seafloor during relative sea level falls and increases in stress as pore fluid drains from the sediment when the platform top becomes subaerially exposed during relative lowstands of sea level the increased likelihood of megabreccia genesis during relative sea level falls is supported by an empirical trend identified from a review of the stratigraphic distribution of documented megabreccias exogenic causes of gravitational instability with inherently random periodicity especially seismicity may account for the small number of documented megabreccias that do not conform to this underlying trend the proposed endogenic pattern favouring megabreccia deposition during relative sea level falls is important in a sequence stratigraphic context megabreccia deposits may build volumetrically significant toe of slope wedges and aprons during relative lowstands of sea level partially compensating for the decrease loss in the supply of fresh granular sediment as the platform top carbonate factory contracts lowstand wedges and aprons in carbonate systems therefore generally differ in composition from equivalent highstand deposits in being composed not of calciturbidite deposits but of megabreccias cannibalized from the upper slope

mineralogical organic and isotopic composition as palaeoenvironmental records in the lake sediments of two lakes the plitvice lakes croatia abstract six sediment cores the top 30 40 cm from two lakes of different sizes lake prosce and lake kalu erovac situated in the karst region of the plitvice lakes system croatia were studied by mineralogical and structural c n and total organic carbon toc and isotopic analyses a14c and 13c of carbonate and organic fractions the study of the two karst lakes where sediment composition is mainly calcite showed that organic matter om also plays an important role and that both fractions analysed simultaneously give a good overview of the processes in the lakes the morphological and structural properties of the calcite particles at micron and submicron levels indicate that the calcite mineral phase is formed by active authigenic precipitation in the studied lake systems in the small lake kalu erovac the measured distributions of carbonate and om fractions c n toc and a14c and 13c values of both fractions along the sediment depth showed similar values for all three cores with small variations in each core indicating very homogenous precipitation of autochthonous calcite inside the lake without allochthonous fraction in the bigger lake prosce the large difference in sediment composition of the three cores indicated different conditions of sediment precipitation inside the lake significant fractions of land derived carbonate and om were recognized by mineralogical c n a14c and 13c values in the shallow coastal area indicating that the sediment was a mixture of allochthonous and autochthonous fractions in contrast the composition of the deep water sediment in the same lake indicated in situ calcite precipitation and aquatic om produced in the lake sedimentation rates of 0 7 cm yr and from 0 3 to 0 7 cm yr for lake prosce and lake kalu erovac respectively were determined based on the a14c of macrofossils extreme hydrological events in 1981 and 2010 were identified by disturbances in carbon isotopes distributions in sediment profiles no evidence of anthropogenic influence in either lake on the local level was found but the response to the global 14c contamination was observed by a14c peaks in both carbonate and organic fractions increased bioproductivity in the recent decades was observed in lake prosce which can be correlated with a slight increase in lake water temperature in the last three decades this process can be associated with enhanced eutrophication in lake prosce

progradational patterns at the head of single units of base of slope submarine granular flow deposits conglomerats des gâs coniacian se france upper cretaceous conglomerates sandstones and calcarenites outcropping in the glandage syncline les gas gorge belong to two superimposed turbidite systems the first being the shortest about two hundred metres thick five kilometres wide and a mere ten kilometres long both onlap a sw ne oriented palaeoslope created by faulting in the latest turonian on the southern edge of the vercors carbonate platform the first system is coniacian in age the second probably campanian this study deals only with the first system which comprises in stratigraphic order classical sandstone turbidites clast supported conglomerates and coarse grained cross bedded sandy calcarenites the transition between the last two lithologies is progressive allowing the mechanisms responsible for apparent lateral accretions found pervasively in both the conglomerates and the calcarenites to be understood here cross bedding is not the result of changes in the direction of accretion in lateral bars or in oblique infillings of sinuous channels as is often suggested in other similar deep water carbonate systems each event bed comprises a prograding conglomeratic head plug blanketed in continuous sedimentation by forward spreading bioclastic calcarenites the superimposition of such mixed beds gives rise to a low angle cross stratification an unusual feature for a system interpreted as a base of slope apron conglomerates were probably deposited through a granular flow mechanism at a strong hydraulic jump at the base of the slope associated calcarenites show supercritical flow features the undulating transverse architecture of its large head onlapping the paleoslope suggests it is a multi apex apron the sandstone conglomerate calcarenite succession of the depositional sequence is interpreted as overall transgressive after the late turonian tectonic phase that led to the exposure of the vercors carbonate platform updip

climatic and environmental controls on speleothem oxygen isotope values variations in speleothem oxygen isotope values d 18 o result from a complicated interplay of environmental controls and processes in the ocean atmosphere soil zone epikarst and cave system as such the controls on speleothem d 18 o values are extremely complex an understanding of the processes that control equilibrium and kinetic fractionation of oxygen isotopes in water and carbonate species is essential for the proper interpretation of speleothem d 18 o as paleoclimate and paleoenvironmental proxies and is best complemented by study of site specific cave processes such as infiltration flow routing drip seasonality and saturation state and cave microclimate among others this review is a process based summary of the multiple controls on d 18 o in the atmosphere soil epikarst and speleothem calcite illustrated with case studies primary controls of d 18 o in the atmosphere include temperature and relative humidity through their role in the multiple isotope effects variability and modifications of water d 18 o values in the soil and epikarst zones are dominated by evaporation mixing and infiltration of source waters the isotopically effective recharge into a cave system consists of those waters that participate in precipitation of caco3 resulting in calcite deposition rates which may be biased to time periods with optimal dripwater saturation state recent modeling experimental and observational data yield insight into the significance of kinetic fractionation between dissolved carbonate phases and solid caco3 and have implications for the hendy test to assist interpretation of speleothem d 18 o time series quantitative and semi quantitative d 18 o climate calibrations are discussed with an emphasis on some of the difficulties inherent in using modern spatial and temporal isotope gradients to interpret speleothems as paleoclimate proxy records finally several case studies of globally significant speleothem paleoclimate records are discussed that show the utility of d 18 o to reconstruct past climate

comparison of esr and tims u th dating of marine isotope stage mis 5e 5c and 5a coral from barbados implications for palaeo sea level changes in the caribbean abstract electron spin resonance esr dating of coral has become an efficient geochronological tool in supporting morphostratigraphic studies carried out on barbados during the last 10 years the newly developed approach for de determination de dmax plot procedure improves the precision of esr dating of pleistocene coral and therefore permits differentiation between the main marine isotope stages mis 5 7 9 and 11 and also between sub stages 5e c and a this study compares results of esr and tims uranium series dating u th of emergent last interglacial coral reef terraces from barbados and presents some implications for the timing and extent of sea level changes during marine isotope stages mis 5e c and a both dating methods indicate a distinct formation of up to three coral reef terraces during mis 5e at approximately 132 ka esr to 128 ka u th at c 128 ka esr and at c 120 ka u th to 118 ka esr it is also highly probable that three reef terraces were developed during mis 5c between c 103 ka u th and 105 ka esr the formation of two separate coral reefs during mis 5a is recognized for the first time on barbados with an age estimate for the older mis 5a 2 reef of 85 ka esr or 84 ka u th and an age estimate for the younger mis 5a 1 reef terraces of 74 ka esr or 77 ka u th assuming a constant uplift rate of 0 276 m ka at the south coast of barbados sea level reached its maximum during mis 5e 3 and mis 5e 2 between 132 and 128 ka ago after this sea level declined reaching a level of c 11 m below present sea level approx 118 120 ka ago mis 5e 1 during the substage 5c sea level was generally lower than in substage 5e it reached relative maxima at c 13 20 and 25 m during mis 5c approx 105 ka and formed three distinct coral reef terraces probably in relative short time intervals for the first time a double sea level oscillation is recognized on barbados during mis 5a an early mis 5a 2 c 85 ka with a sea level places at approx 21 m and a late mis 5a 1 sub stage c 74 or 77 ka with a sea level at approx 19 m below present sea level

palaeoclimate determination from cave calcite deposits calcite deposits formed in limestone caves have been found to be an excellent repository of palaeoclimatic data for terrestrial environments the very presence of a relict deposit indicates non glacial conditions at the time of formation and both 14c and uranium series methods can be used to date the deposit and hence the age of these climatic conditions variations in 13c and 18o content of the calcite in 2h and 18o content of fluid inclusions in trace element concentrations and more recently in pollen assemblages trapped in the calcite are all potentially available as synchronous palaeoclimatic indicators previous work has tended to concentrate mainly on abundance of deposits as a palaeoclimatic indicator for the last 300 000 years this literature is briefly reviewed here together with the theory and methods of analysis of the u series and stable isotopic techniques the combined use of u series ages and 13c and 18o variations in cave calcites illustrates the potential for palaeoclimate determination previously unpublished results of stable isotopic variations in dated calcites from caves in northern england indicate the level of detail of stable isotopic variations and time resolution that can be obtained and the complexity of interpretation that may arise tentative palaeoclimatic signals for the periods 90 125 ka and 170 300 ka are presented more comprehensive studies are needed in future work especially in view of the difficulty in obtaining suitable deposits and the ethics of cave deposits conservation

monitoring of selected caves as a prerequisite for the speleothem based reconstruction of the quaternary environment in croatia abstract quaternary palaeo environmental changes that have taken place in croatia are likely to be recorded in speleothems secondary carbonate deposits precipitated in caves confident interpretation of well dated speleothem proxy records relies on modern monitoring programs which we provided in three regionally different caves parallel monitoring of the surface and cave air temperature and relative humidity precipitation and cave drip intensity as well as stable isotope modification of meteoric and drip water was carried out in order to estimate the most reliable stalagmites for the interpretation of quaternary landscape history in all three caves nova grgosova 239 m a s l t cave 11 2 c in central croatia lokvarka 780 m a s l t cave 7 5 c in the mountainous part of croatia and modric 32 m a s l t cave 16 6 c in coastal croatia we selected the parts of the caves where the ambient cave conditions appeared to be appropriate for equilibrium deposition of calcite in terms of constant air temperature seasonal amplitudes of 0 73 0 38 and 0 45 c respectively and relative humidity 100 both atlantic and mediterranean moisture influences were detected in all three caves but of different intensities cave hydrological settings governed by karst aquifer properties were resolved by the comparison of the precipitation intensities and drip site responses to the rain events and generally seasonal rainwater isotopic signal was almost completely attenuated except for one drip site such homogenized drip water and stable cave environmental settings give confidence for calcite deposition under equilibrium conditions especially for modric and nova grgosova caves where speleothems inner structures also look promising for potentially quality dating results and stable isotopic profiles the fracture flow drip regime of selected drip sites in lokvarka cave and uncompleted homogenization of the water in the epikarst might point to speleothem samples that are unsuitable for resolving multi annual quaternary climate changes this view is supported by the high porosity internal structure of some lokvarka speleothems so further monitoring sampling and the thorough speleothem examination is therefore necessary for adequate interpretations of palaeo environmental changes

sea level controls sedimentation and environments in coastal caves and sinkholes abstract quaternary climate and sea level research in coastal karst basins caves cenotes sinkholes blueholes etc generally focuses on analyzing isotopes in speleothems or associating cave elevations prior sea level highstands the sediments in coastal karst basins represent an overlooked source of climate and sea level information in the coastal zone but to accurately interpret these sediments first requires an understanding of the forcing mechanisms that emplace them in this study we hypothesize that coastal karst basins transition through vadose littoral anchialine and finally into submarine environments during sea level rise because groundwater and sea level oscillate in near synchrony in the coastal zone causing each environment to deposit a unique sedimentary facies to test this hypothesis the stratigraphy in twelve sediment cores from a bermudian underwater cave green bay cave was investigated and temporally constrained with twenty radiocarbon dates the results indicate that we recovered the first succession spanning the entire holocene from an underwater cave 13 ka to present the sediments were characterized with x radiography fossil remains bulk organic matter organic geochemistry 13corg c n and grain size analysis four distinct facies represent the four depositional environments i vadose facies 7 7 ka calcite rafts lithofacies ii littoral facies 7 7 to 7 3 ka calcite rafts and mud lithofacies iii anchialine facies 7 3 to 1 6 ka slackwater and diamict lithofacies and iv submarine facies

neotectonic movement earthquakes and stress state in the eastern united states abstract a regional pattern of crustal movement across the eastern united states is suggested by relations found by investigations into the cause of earthquakes the pattern consists of zones of fractures and vertical movement most of the seismic source areas appear to be related to northwest trending fracture zones that commonly have apparent righ lateral strike slip offset where they cross broad northeast trending belts of vertical movement the fracture zones also appear to control the positions of local northwest trending basins embayments on the atlantic and gulf coastal plains these embayments seem to be relatively subsiding at present and have earthquakes associated with them intervening arches have very few earthquakes some earthquakes are also spatially related to north trending extensional fault zones that commonly lie north of northwest trending fracture zones a slight northward tilt of the entire region and possible lingering effects of glacial rebound in the northeast show no relation with seismicity both the broad belts of vertical movement and embayments are apparently those initiated by the late cretaceous as the north atlantic basin widened and the northwest trending fracture zones can be directly or indirectly related to the offshore transform fracture zones the interplate movements in the eastern united states are thus directly related to those in the north atlantic basin the fracture pattern is also similar to that of the western united states but the movements less these tectonic movements in the eastern united states can be accounted for by a maximum horizontal compressive stress oriented approximately north northwest south southeast to north south and an extension oriented approximately east west