bryozoans as carbonate sediment producers on the cool water lacepede shelf southern australia abstract modern sediments on the lacepede shelf and adjacent slope are typical mid latitude cool water palimpsest deposits dominated by bryozoan mollusc and quartz particles bryozoan bioclasts form autochthonous and to a lesser extent allochthonous accumulations across the grain size spectrum from mud to boulder size the bryozoan skeletons are grouped on the basis of architecture and style of disarticulation fragmentation into nine morphotypes erect rigid forms comprise 1 fenestrate 2 foliose 3 flat robust branching and 4 delicate branching morphotypes large adeona sp skeletons are recognised as a separate type of fenestrate form because of their distinctive shape mineralogy and restricted environment erect flexible forms are either 5 articulated branching or 6 articulated zooidal other important morphotypes are 7 encrusting 8 nodular arborescent and 9 vagrant differences in skeletal architecture result in distinct particle types encrusting morphotypes on soft organic substrates and the wide variety of erect rigid forms are broken into fragments erect flexible forms disintegrate upon death into definitive sand and silt size grains encrusting morphotypes on hard substrates nodular arborescent and vagrant forms remain whole and when large accumulate in place morphotypes are mineralogically distinct and so bryozoan sediment composition is environmentally controlled shallow water

u series dating of fossil teeth and carbonates from snake cave thailand abstract snake cave thailand is an important site for the study of the evolution in southeast asia leading to a discovery of rich and various faunas including a human tooth fossils of large and small mammals converge to indicate on the basis of faunal assemblage a late middle pleistocene age for the fossiliferous layers on the other hand previous u series dating of carbonates furnished a lower limit for the fossils of about 130 ky in order to achieve a better comprehension of the chronology of the cave the uranium series method for absolute age determination has been applied to some carbonates older than those studied previously and to fossils themselves we used the isochron technique approach to yield valuable ages because spleleothem samples consist in a mixture of calcite and detrital contamination the results obtained suggest that the main fossiliferous level is older than about 160 ky the application of the u series method to tooth samples from this tropical cave leads to erroneous ages probably because of post depositional groundwater movements

restrictions on fluorine depth profiling for exposure age dating in archaeological bones archaeological fragments of bone and teeth that are exposed to a humid environment take up fluorine from the surrounding soil the fluorine ion replaces the hydroxyl group in the mineral phase of the bone forming chemically more stable fluorapatite in cortical parts of the long bone diaphysis a fluorine concentration profile can be observed which decreases from the outer surface and the marrow cavity towards the inner parts of the bone matrix geological time spans are needed for this process to reach equilibrium and for the distribution to become uniform as the shape of the profile which can be described by a diffusion model contains information on the exposure duration of the fossil object several attempts to use fluorine profiling as a dating method have been undertaken the distribution of fluorine in an archaeological sample however is strongly influenced by environmentally induced processes of bone diagenesis i e alteration in the structure and composition of the mineral phase and degradation of organic components that may make the time information indistinct the primary chemical composition of bones can thus be obscured by diagenesis within tens hundreds or thousands of years this depends more on the diagenetic environment than on the geological age to observe the impact of environmental influence on the profile shape samples from several burial sites featuring various soil conditions have been analyzed for their fluorine distribution and preservation state this paper provides an overview on the restrictions that have to be considered when attempts are undertaken to relate a fluorine diffusion pattern to the archaeological age of a bone specimen

the precision of porosity measurements effects of sample pre treatment on porosity measurements of modern and archaeological bone abstract bone porosity plays an important role in the taphonomic trajectory of bones porosity analysis of archaeological material can indicate diagenetic events in the bones taphonomic history furthermore measuring the porosity of modern bone material can potentially provide a method for assessing the relative likelihood of survival for different skeletal elements here we critically assess the use of nitrogen adsorption porosimetry and mercury intrusion porosimetry for analysing porosity of a range of bone preservation types from modern fresh material to highly degraded archaeological material in addition a number of sample preparation methods were assessed our results indicate that bone porosity measurements show large variation which may limit their usefulness when analysing modern material features observed in pore size distribution graphs are however consistent and thus this data would appear to be a useful indicator of diagenetic processes that have occurred in the bone the most effective method for preparation of the bone is lyophilisation which renders the bone dry enough for analysis and does not appear to cause a visible systematic error in the measurements

early diagenesis of bone and tooth apatite in fluvial and marine settings constraints from combined oxygen isotope nitrogen and ree analysis abstract fossil bones and teeth of late pleistocene terrestrial mammals from rhine river gravels rs and the north sea ns that have been exposed to chemically and isotopically distinct diagenetic fluids fresh water versus seawater were investigated to study the effects of early diagenesis on biogenic apatite changes in phosphate oxygen isotopic composition 18opo4 nitrogen content wt n and rare earth element ree concentrations were measured along profiles within bones that have not been completely fossilized and in skeletal tissues bone dentine enamel with different susceptibilities to diagenetic alteration early diagenetic changes of elemental and isotopic compositions of apatite in fossil bone are related to the loss of the stabilizing collagen matrix the ree concentration is negatively correlated with the nitrogen content and therefore the amount of collagen provides a sensitive proxy for early diagenetic alteration ree patterns of rs and ns bones indicate initial fossilization in a fresh water fluid with similar ree compositions bones from both settings have nearly collagen free ree u f and sr enriched altered outer rims while the collagen bearing bone compacta in the central part often display early diagenetic pyrite void fillings however ns bones exposed to holocene seawater have outer rim 18opo4 values that are 1 1 to 2 6 higher compared to the central part of the same bones 18opo4 18 2 0 9 n 19 surprisingly even the collagen rich bone compacta with low ree contents and apatite crystallinity seems altered as ns tooth enamel 18opo4 15 0 0 3 n 4 has about 3 lower 18opo4 values values that are also similar to those of enamel from rs teeth therefore ree concentration n content and apatite crystallinity are in this case only poor proxies for the alteration of 18opo4 values seawater exposure of a few years up to 8 kyr can change the 18opo4 values of the bone apatite by 3 therefore bones fossilized in marine settings must be treated with caution for palaeoclimatic reconstructions however enamel seems to preserve pristine 18opo4 values on this time scale using species specific calibrations for modern mammals a mean 18oh2o value can be reconstructed for late pleistocene mammalian drinking water of around 9 2 0 5 which is similar to that of late pleistocene groundwater from central europe

supply and dispersal of flood sediment from a steep tropical watershed hanalei bay kaua i hawai i usa in contrast to many small mountainous watersheds in temperate coastal regions where fl uvial discharge and wave energy commonly coincide deposition and reworking of tropical fl ood sediment can be seasonally decoupled and this has important implications for coral reef ecosystems an understanding of the interaction between tropical fl ood sedimentation and wave climate is essential to identifying and mitigating effects of watershed changes on coral reefs as urbanization and climate change proceed sedimentary facies and isotopic properties of sediment in hanalei bay on the island of kaua i hawai i usa were used to assess deposition and reworking of fldeposits from the hanalei river in a case study demonstrating the potential ecosystem effects of runoff from a steep tropical watershed in hanalei bay the youngest and thickest terrigenous sediment was consistently present near the river mouth and in a bathymetric depression that acted as at least a temporary sediment sink during this 2 yr study the largest fl ood events occurred in late winter and spring 2006 substantial terrestrial sediment delivered by those fl oods still remained in the bay as of june 2006 because oceanic conditions were not suffi ciently energetic to transport all of the sediment offshore additional sediment was deposited in the bay by a summer 2006 fl ood that coincided with seasonal low wave energy in most years fl ood sediment accumulating in the bay and on its fringing reefs would be remobilized and advected out of the bay during winter when the wave climate is energetic turbidity and sedimentation on corals resulting from late spring and summer fl oods during low wave energy could have a greater impact on coral reef ecosystems than fl oods in other seasons an effect that could be exacerbated if the incidence and sediment load of tropical summer fl oods increase due to urbanization and climate change

paleoenvironmental reconstruction of the early to middle miocene central paratethys using stable isotopes from bryozoan skeletons stable carbon and oxygen isotope values from single bryozoan colonies were used to reconstruct the paleoenvironments of the early to middle miocene ottnangian to badenian sediments of the central paratethys this approach utilizes a locally abundant allochem while avoiding matrix and multiple allochem contamination from bulk rock samples bryozoan colonies and a few foraminifera and rock matrix samples from 14 localities yielded 399 carbon and oxygen isotope values data from six of the localities 15 of the total number of samples were interpreted as having been diagenetically altered and were rejected the remaining data indicate a primarily localized upwelling signal with lesser variation caused by global climatic and regional tectonic forcing of sea level salinity and temperature paleotemperatures were calculated to range from 12 to 21 c despite potential taxonomic and diagenetic problems bryozoan colonies are a powerful underutilized source of paleoenvironmental carbon and oxygen isotope data

paleocene lower eocene carbonate platforms of westernmost tethys abstract the paleocene lower eocene succession is well exposed in sierra espuna mula basin betic cordillera s spain and carbonate platforms are well represented as part of this succession the study of the paleoenvironmental evolution of these platforms has allowed to cover an important gap in the knowledge in the westernmost tethys thirteen microfacies mf1 to mf13 were recognized based mainly on the fossil assemblage principally larger benthic foraminifera texture and fabric of the microfacies the fossiliferous assemblage of the entire succession shows a mixture of photozoan and heterotrophic biogenic elements typical of an inner to outer ramp environment of a warm temperate biogeographic province fragments of hermatypic corals have also been detected in the lower part of the succession paleocene allowing thinking in propitious conditions in this period the succession evolves upwards lower eocene to low energy shallow marine protected environments lagoon in inner ramp settings in addition abundant porcelaneous larger benthic foraminifera such as alveolinids and soritids are indicative of euphotic shallow marine conditions in moderately oligotrophic upper subtidal environments in the upper part of the succession hermatypic corals as displaced fragments and in situ isolated coral phaceloid colonies also appear together with other biogenic components indicating warm shallow and euphotic marine conditions coral maerl environment lenticular larger benthic foraminifera characterizing marine mesophotic and oligotrophic habitats can be found in the upper part of the middle ramp and flattened larger benthic foraminifera forms indicating lowermost mesophotic conditions in a distal middle ramp the obtained results have been compared with other similar tethyan sectors obtaining a broader view the biogenic marine association is characterized by the absence of the lockhartia community of the tethyan domain together with the dominance of alveolinids nummulitids and orthophragminids during most of the paleocene northern mediterranean tethys platforms were located in the middle paleolatitudes and characterized by coral reef and coralgal biofacies the studied platforms located at a latitude close to 25 n show in a ramp like context underdeveloped in situ coral constructions probably of patch reef type in the early eocene the expansion and abundance of the larger benthic foraminifera and the practical disappearance of coral took place in the sedimentary platforms through the entire tethys however in the study area small reef coral build ups have also been observed in the lower cuisian beds indicating that in westernmost tethys coral construction continued at these latitudes

bone diagenesis and origin of calcium phosphate nodules from a hominid site in the lukeino formation tugen hills kenya the lukeino formation 6 09 5 68 ma kenya is a fossiliferous fluvio lacustrine sedimentary sequence 100 m thick which yielded the fossil remains of the oldest east african bipedal hominid called orrorin tugenensis at one of the hominid sites aragai centimetric to pluri centimetric indurated calcium phosphate nodules occur in a specific sedimentary layer mineralogical and geochemical analyses coupled with sem optical microscopy and cathodoluminescence observations were performed on four calcium phosphate nodules and one bone showing differential alteration with characteristics locally similar to that of the nodules in order to determine the nature and origin of these nodules a crystallinity index ci and histological index hi were also assigned to these samples to characterize their degree of transformation analyses reveal that all nodules and the studied bone have a similar mineralogical and chemical composition nodules show no internal structure and are composed of a carbonate fluorapatite matrix including feldspars clays and spheres of iron and manganese oxides their high ci indicates significant recrystallization compared to modern bone the altered bone shows infilling of the trabecular cavities characterized by a clay deposit along the walls oxide spheres with a silica center and carbonate fluorapatite baguettes in the highly altered area of the bone a phenomenon of dissolution and dismantlement of bone structures adjacent to an area characterized by the presence of a phosphate matrix is observed the genesis of these calcium phosphate nodules seems to result from an advanced stage of transformation of bones due to a combination of physical chemical and biological bacterial processes the different stages of diagenesis are characterized by the incorporation of components from the sedimentary layer including diatoms and by neoformations of clays and oxides in the bone pores the bone structure is affected by fracturing and dissolution of carbonate hydroxylapatite which reprecipitated in bone cavities under the form of carbonate fluorapatite automorphic crystals then the bone structures and mineral neoformations were affected by a dismantlement phenomenon which increased the dissolution of the bone apatite this resulted in a carbonate fluorapatite matrix in which no trace of the initial bone structure is visible this particular mechanism of genesis of calcium phosphate nodules most probably takes place by action of fluid circulation in a confined environment such as a lake edge or marsh

changes in bryozoan assemblages and bathymetric variations examples from the messinian of northwest algeria abstract studies of recent bryozoan faunas have shown that there is a correlation between colonial growth forms and various physical factors of the environment especially bathymetry each given assemblage of zoarial forms can thus be related to a certain depth interval in marine neogene deposits numerous extant bryozoan species occur and some of them have more or less restricted depth ranges they are used here to complement the indications given by the analysis of growth forms in the messinian uppermost miocene of northwestern algeria a general feature is the occurrence of well developed diatomaceous deposits interbedded with marl beds where benthic invertebrate remains are often abundant in the five sections under study bryozoans are represented by 87 species belonging to nine different colonial growth forms four different assemblages of these zoarial forms characterised by presence absence and number of fragments are distinguished corresponding to four depth intervals the first and deepest assemblage upper bathyal to lower circalittoral occurs in the bottom part of the sections where colonies of a conescharelliniform species strongly predominate the second assemblage lower circalittoral is represented by several species belonging to various zoarial forms conescharelliniform cellariiform vinculariiform adeoniform and reteporiform the third assemblage upper circalittoral is characterised by the absence of conescharelliniforms but membraniporiforms and celleporiforms are abundantly represented together with numerous erect colony fragments in the fourth assemblage infralittoral membraniporiforms and celleporiforms predominate although a number of erect zoarial forms are sometimes associated in various proportions the presence of several extant bryozoan species associated with each of these four assemblages is used as a confirmation for the suggested depth intervals a gradual shallowing is thus indicated by the study of the bryozoan assemblages through the five messinian sections the discussion shows that modern data on zoarial forms and species bathymetric distributions are clearly applicable to cenozoic faunas but that caution must be exercised when using results obtained from different oceanographic regions

pre screening techniques for identification of samples suitable for radiocarbon dating of poorly preserved bones under certain environmental conditions post depositional diagenetic loss of bone collagen can severely reduce the number of bones from a particular archaeological site that are suitable for stable isotopic analysis or radiocarbon dating this study examined nearly 300 bones from 12 archaeological sites across southern england known to yield poor or variable preservation to try to identify one or more pre screening technique s that would indicate suitable collagen preservation for radiocarbon dating the most reliable method was shown to be the percent nitrogen n of whole bone powder which has an 84 chance of successfully predicting whether or not a bone will yield sufficient i e 1 weight collagen for dating

pleistocene calabrian deep water corals and associated biodiversity in the eastern mediterranean karpathos island greece diversified deep water corals and associated communities occur in early pleistocene early calabrian 1 7 1 6 ma calcareous crusts discovered on the south western coast of karpathos island eastern greece apart from abundant and conspicuous solitary and colonial corals 12 species the accompanying fauna comprises mostly bivalves 10 species serpulid worms 4 species and bryozoans 40 species the growth and deposition of the studied organisms occurred in an upper bathyal environment at water depths around 400 600 m the calculated mean uplift rate after deposition of the crusts indicates that karpathos was drowned during the earliest calabrian and experienced severe uplifts by the late calabrian a comparison between these communities and those of the pleistocene to recent mediterranean and north east atlantic shows that a common stock of taxa exist ed among them two azooxanthellate colonial scleractinians lophelia pertusa and madrepora oculata are predominant

surficial cool water carbonate sediments on the otway continental margin southeastern australia abstract the otway continental margin of southern australia is a swell dominated open cool water carbonate platform it is partitioned into a series of depth related zones of biological sediment production and accumulation by three hydrodynamic interfaces 1 abrasion depth 70 m 2 swell wavebase 130 m and 3 storm wavebase 250 m the otway shelf profile drops steeply from the strandline the shallow shelf lies largely between 30 and 70 m and is a high energy zone of carbonate sediment production intensive destructive diagenesis and erosion the seafloor is characterized by widespread exhumed limestone substrates which host dense encrusting assemblages of molluscs sponges bryozoans and red algae loose sediment accumulation is patchy and consists of a thin quartz rich palimpsest gravel veneer the middle shelf 70 to 130 m is a zone of swell wave shoaling and production and accumulation of coarse mega rippled 2 d dunes bryozoan sands deep shelf areas 130 to 180 m accumulate finer bioclastic sands foraminiferal echinoid bryozoan that are intensely bioturbated and episodically reworked by storms grains are variably fragmented and marginally bored at the shelf edge and top of slope 180 to 350 m nutrient rich upwelling currents support laterally extensive aphotic biostromal hermal bryozoan sponge coral communities which generate and accumulate thick successions of muddy skeletal sand sediments of the upper slope 350 to 500 m are a bioturbated mixture of periplatform bioclastic debris and pelleted foraminiferal nannofossil mud turbidites and resedimentation features are common bioturbation and shelf derived skeletal content decrease progressively downslope and pelagic muds dominate below 500 m lower slope areas are cross cut by gullies and have low accumulation rates the base of slope is characterized by sediment apron deposits consisting of interbedded shelf derived coarse grained turbidites and pelagic ooze

an unusual messinian succession in the sinis peninsula western sardinia italy abstract recently completed sedimentological and palaeontological analyses of the messinian deposits of western sardinia yielded dating palaeoenvironmental and new sequence stratigraphic interpretations the basal marls and the capo san marco formation are referred to the messinian both formations were deposited in a ramp setting whereas the overlaying sinis limestone formation is interpreted as a carbonate platform of wide extent probably equivalent to part of the terminal carbonate complex all these deposits are considered to have formed under normal marine conditions the three formations developed during one and a half cycles of progradation retrogradation compared with other messinian mediterranean carbonate platforms the sinis peninsula exhibits several unusual features 1 the notable absence of scleractinian coral reefs is related to dominantly cool seawater in this area 2 the capo san marco formation contains widespread microbial bryozoan serpulid carbonate buildups partially associated with upwelling currents 3 the breccias at the top of the sinis limestone formation are regarded as resulting from a major seismic shock over the whole peninsula

the oligocene miocene stratigraphic evolution of the majella carbonate platform central apennines italy abstract the stratigraphic architecture of the bolognano formation documents the evolution of the majella carbonate platform in response to global and local changes that affected the mediterranean area during the oligocene miocene interval the bolognano formation consists of a homoclinal ramp that developed in a warm subtropical environment five different lithofacies associations have been identified lepidocyclina calcarenites cherty marly limestones bryozon calcarenites hemipelagic marls and marly limestones and lithothamnion limestones each association corresponds to a single lithostratigraphic unit except for the lepidocyclina calcarenites that form two distinct lithostratigraphic units lepidocyclina calcarenites 1 and 2 these six units reflect alternation of shallow water carbonate production and drowning specifically two of the three stages of shallow water carbonate production regard the development of wide dune fields within the middle ramp one stage dominated by red algae and a sea grass carbonate factory whereas the two drowning phases are represented by marly cherty limestones and calcareous marls a new biostratigraphic framework for bolognano formation is presented based on high resolution analysis of calcareous nannofossil assemblages which proved to be very useful for biostratigraphic constraints also in shallow water settings using this approach we have linked the first drowning phase late chattian aquitanian p p in age to western mediterranean volcanism and the mi 1 event and the second drowning phase late burdigalian serravallian in age to the closure of the indo pacific passage and the occurrence of the global monterey event these results permit a new deciphering in terms of sequence stratigraphy of the bolognano formation that is interpreted as a 2nd order super sequence that can be subdivided into 3 transgressive regressive sequences

identification of degraded bone and tooth splinters from arid environments using palaeoproteomics abstract the analysis of the skeletal remains of vertebrates in archaeological contexts provides information about human animal relationship and their environment their taxonomic identification based on macroscopic observation is not always possible due to fragmentation and poor preservation in recent years proteomics has emerged as an alternative but there is clearly a lack of data in arid environment where diagenesis rapidly affects the integrity of bone proteins here we report the efficiency of three protocols for protein extraction the protocols used harsh 1 m hcl and 0 6 m hcl and soft tris edta decalcification agents and were tested on unidentified splinters from the 2000 years old site of toteng botswana the preservation of the organic phase was first estimated using attenuated total reflectance fourier transform infrared spectroscopy and a set of samples with contrasted collagen contents were selected for palaeoproteomics the extracted proteins were submitted to a bottom up proteomic approach involving trypsin digestion followed by ultra high performance liquid chromatography coupled to mass spectrometry uhplc ms our results identify tris edta buffer as the most suitable decalcification protocol for poorly preserved bones and propose a collagen content threshold of 3 weight content for successful detection of peptides this approach combined with biogeographical and chronological repartitions of mammals in africa allows refining taxonomic attributions for four out of nine splinters leading to species identification data are available via proteomexchange with identifier pxd010725

bone diagenesis in the european holocene ii taphonomic and environmental considerations we have applied cluster analysis to mercury intrusion porosimetry data from 219 archaeological bones 121 human and 98 animal and soil chemistry data from 219 accompanying soil samples 1 per bone sample to investigate the influence of soil chemistry on bone preservation the samples chosen for the study were obtained from sites ranging in time from the pre modern to the mesolithic and were representative of burial environments across europe from the baltic to the mediterranean these results represent the single largest database for archaeological bone preservation in the european holocene to date and demonstrate the potential for large scale diagenetic studies to help develop long term preservation strategies for our european heritage despite the variety of sites and environments bones could be categorised into only four main diagenetic types furthermore soil chemistry appears to significantly affect only one type of preservation the pathway characterised by loss of mineral in neutral to basic soils taphonomy and in particular the differences between the treatment of human and animal remains becomes the dominating factor in determining preservation using these results strategies for heritage management of archaeological sites can be suggested grouping sites into those requiring immediate excavation and those where in situ preservation is viable

micromorphological indicators for degradation processes in archaeological bone from temperate european wetland sites abstract micromorphological investigations of archaeological bones make it possible to study decay processes and the associated depositional environment in one go a selection of micromorphological thin sections from soil samples from three wetland sites in switzerland the netherlands and norway that contained bone fragments were studied the goal was to investigate the type and the timing of decay processes to better understand the taphonomy of bones in such sites using optical microscopy and scanning electron microscopy with energy dispersive x ray spectroscopy sem edx a range of biological decay processes and chemical mineralogical transformations were observed in two of the sites zug riedmatt in switzerland and hazendonk in the netherlands a relatively short exposure to adverse conditions must have occurred some of the bones from zug riedmatt show localized collagen decay related to exposure to fresh ashes others show cyanobacterial tunnelling related to submersion in shallow clear water in hazendonk bone fragments and fish scales apparently have first been exposed to bacterial decay related to putrefaction subsequently alternations between wet and dry conditions resulted in the dissolution of some of the bone mineral and the formation of ca fe iii phosphates probably mitridatite fungal decay caused extensive tunnelling of bone and fish scales as well as the secondary phosphates these processes apparently ended when the bone rich layer became permanently waterlogged and anoxic in stavanger bone mineral is transformed into mitridatite and possibly other ca fe iii phosphates indications that the redox conditions are variable at present suggest that these processes are still active

application of bryozoan zoarial growth form studies in facies analysis of non tropical carbonate deposits in new zealand abstract the fragmental remains of bryozoan colonies are the dominant skeletal contributor in many modern and ancient occurrences of non tropical shelf carbonate deposits the taxonomic complexity of the bryozoa the difficulties of systematic classification except by specialists the wide range of particle sizes and of preservation state in the carbonate deposits and the often well cemented nature of host limestones all limit the sedimentological interpretation of the commonly diverse bryozoan component however following the pioneer work of stach in the 1930 s the potential exists for sedimentologists to obtain useful paleo environmental information about the deposits by recording simply the nature and relative abundances of the various growth shapes of the bryozoan material known as their zoarial colonial growth forms here we propose a simple descriptive terminology covering both cheilostome and cyclostome bryozoans that involves four main growth forms encrusting erect rigid erect flexible and free living and a selection of subcategories based on shape identification of these habitat related growth form types is aided by reference to line drawings specimen photographs and photomicrographs of thin section slices the scheme is illustrated by examining briefly some possible environmental controls on the spatial and or time variations in the nature and distribution of colonial growth forms in several examples of modern and tertiary bryozoan dominated carbonate deposits in new zealand we anticipate that the routine description and quantification of bryozoan colonial growth types in non tropical carbonates generally will facilitate the recognition and interpretation of contrasting sub facies within the global foramol bryomol group of carbonate deposits

mosaic of environments recorded by bryozoan faunas from the middle miocene of hungary the marine sediments of the badenian middle miocene of hungary pannonian basin central paratethys are composed of abundant bryozoan skeletal grains seventy one bulk samples collected at 18 localities outcrops and boreholes yielded a total number of 238 bryozoan species in order to reconstruct the badenian palaeoenvironments the present study investigates the composition of this very diverse fauna using a combination of statistical and palaeoecological methods the statistical analyses make use of cluster analysis and non metric multi dimensional scaling the palaeoecological approaches are based on the known ecological requirements of the bryozoan colonial growth forms and of the numerous extant species five facies have first been differentiated on the basis of sedimentological and palaeontological features coral buildups coralline algal limestones biocalcarenites sands and marls each of them is characterized by the abundance the diversity and the types of growth forms of the bryozoans the palaeoecological statistical and facies analyses further permitted to identify four depositional settings carbonate platform distal and proximal terrigenous platform slope and basin these environments developed at depths between 0 to about 300 m in a mixed carbonate siliciclastic depositional system skeletal production and spatial distribution of carbonate factories were predominantly controlled by terrigenous input this resulted in a complex mosaic of facies habitats where rich bryozoan faunas could thrive many warm water organisms among them foraminifers zooxanthellate corals molluscs bryozoans and echinoids were recorded from the study sites the coexistence of coralgal and bryomol carbonate skeletal assemblages in this subtropical setting is explained mostly by variations in the productivity of surface waters periods of nutrient enrichment and increased benthic eutrophication affected coral diversity and abundance in favour of bryozoans

bryozoan beds in northern italy as a shallow water expression of environmental changes during the oligocene isotope event 1 abstract shifts in carbonate producing biotic communities in the geological record provide evidence of past environmental changes in the neritic realm the shallow marine calcare di nago formation exposed in the san valentino section northern italy covers the late eocene and earliest oligocene the succession is characterized by the occurrence of light dependent biota such as coralline algae and larger benthic foraminifera in the uppermost part of the section however the fossil association is dominated by bryozoans which are filter feeder organisms this ca 12 m thick interval locally contains up to 86 bryozoans while coralline algae as well as larger benthic foraminifera are absent coralline algae and nummulitid foraminifera recover in the upper part of the bryozoan beds whereas orthophragminids do not recover the gradual disappearance of larger foraminifera and coralline algae within the bryozoan dominated deposits is coeval with a pronounced positive shift in 13c based on its biostratigraphic position this positive shift is interpreted to be linked to the positive shift in 13c recognized in deep sea records shortly above the eocene oligocene boundary which in turn is associated to the positive shift in 18o leading to the oi 1 oligocene isotope event 1 cooling phase total phosphorus content increases in the bryozoan beds suggesting enhanced nutrient supply to the neritic ecosystem this phosphorous peak is coeval with the globally recognized increment in ocean productivity around the oi 1 and 13c positive shift thus disappearance of light dependent biota and the dominance of bryozoans in the platform carbonates studied are interpreted to result not necessarily from a deepening of the depositional environment but from the combination of lower sea surface temperatures and the deterioration of underwater light conditions on account of elevated turbidity in surface waters resulting from enhanced primary productivity as bryozoan beds occur in several italian localities around the eocene oligocene boundary they are interpreted to represent the regional expression of neritic carbonate depositional systems to global environmental changes occurring at the dawn of an ice house earth

high resolution records of location and stratigraphic provenance from the rare earth element composition of fossil bones abstract bone apatite acts as a natural timed sampling device scavenging trace elements from local pore waters over timescales of ca 1 50 ka the rare earth element ree and u th composition of fossil bones reflects associated pore water compositions during the period of recrystallisation the ree composition of fossil bones is controlled by partitioning of ree between pore waters and particle surfaces and the ree composition of fossil bones reflects the ree composition of pore waters which vary spatially and temporally light ree are preferentially sorped onto particle surfaces thus the high la yb values seen in many bones from coastal marine and aeolian environments are best explained by release of ree from light ree enriched particles to local pore waters and subsequent immobilisation in recrystallising bones the ree compositions of bones recovered from pedogenically altered diatomite sediments of the olorgesailie formation of southern kenya vary over spatial scales of less than 10 m location accounts for 48 of the observed variation in bone chemistry and bones recovered from eight discrete excavations within the same time equivalent stratigraphic layer can be assigned to their excavation location with 70 accuracy based on a discriminant analysis of ree u and th composition despite this within layer variation bones recovered from different stratigraphic horizons within the olorgesailie formation can also be distinguished on the basis of their trace element composition bones recovered from four stratigraphic horizons spanning ca 0 5 million years were assigned to their correct stratigraphic layer with 90 accuracy where sedimentological conditions are favourable the trace element composition of fossil bone may be used to test stratigraphic provenance and burial location in excavated bone with a temporal resolution of

a new taphonomic bioerosion in a miocene lakeshore environment abstract this study describes a new type of taphonomic alteration of fossil bone that occurred in a continental carbonate palaeolake environment at the reference spanish miocene site of cerro de la garita concud teruel scanning electron microscopy showed this type of alteration to be characterized by microtunnels that penetrate inward from the bone surface and by a branching meandering arrangement of microchannels on the bone surface these microtunnels had a highly electron dense inner wall seen as a characteristic rim in transverse section microspheres were seen inside the microtunnels both this electron dense layer and these microspheres were found to be composed of calcium phosphate these taphonomic modifications bear some similarities to but also differs from those caused by bacterial attack on bone and enamel in marine and terrestrial environments suggesting the present process to be a new type of bioerosion the microspheres inside the microtunnels were similar in size shape and composition to the fossilized bacteria covering fossils from fossil lagersttaten palaeolake sites such as libros teruel spain and messel germany under the transmission electron microscope these structures showed an apparent cell wall suggesting them to be fossilized coccoid bacteria

stratigraphic sedimentology of tertiary cool water limestones se australia abstract mid tertiary limestones exposed as sea cliffs along the coast of victoria southeastern australia accumulated on the inner part of a cool water distally steepened ramp or open shelf all sediments are bioclastic dominated by particles of bryozoans echinoderms benthic foraminifers brachiopods and molluscs shallow grainy facies also contain coralline algae quartz and glauconite while deep muddy facies include ahermatypic corals ostracodes sponge spicules planktic foraminifers and terrigenous clays the fundamental depositional unit is a meter scale subtidal cycle or rhythm shallow shelf cycles are shallowing upward cross bedded or burrowed grainstone capped by a marine cemented hardground or quartz granule lag while mid shelf cycles are upward coarsening and thickening proximal to distal tempestites such cycles are interpreted to form by eustatically driven climatically controlled oscillations in abrasion wave base and swell wave base deep shelf rhythms are interbedded bryozoan marl and calcareous clay thought to be generated by climatically influenced fluctuations in carbonate productivity and terrigenous dilution lowstand systems tracts are depositional or erosional sequence boundaries are complex multigeneration mostly submarine surfaces condensed cycle boundaries that can be traced offshore into multiple omission surfaces and conformable contacts basinward facies shifts result in deposition of condensed lowstand wedges of stacked shallowing upward grainstone cycles transgressive systems tracts are thick bryozoan marl calcareous clay rhythms associated with facies backstepping and abrupt deepening such rhythmites typically grade stratigraphically upward into tempestite cycles highstand systems tracts are highly progradational wedge shaped rock bodies of shallowing upward grainy cycles these limestones provide the critical link of stratigraphy between modern cool water carbonate shelf deposits and the older mesozoic and paleozoic record of similar sediments

the western edge of the mediterranean pelagian platform a messinian mixed siliciclastic carbonate ramp in northern tunisia the marine messinian deposits of tunisia cover a narrow littoral strip some 300 km long between the northern bizerte and cap bon areas and the central eastern sahel region litho and biofacies analysis of six stratigraphic sections reveals the distinctive features of these deposits the lower messinian deposits are characterized by ubiquitous siliciclastics and abundant oolitic bioclastic limestones organized in an eastward facing ramp westward landward this ramp changes into coastal lagoons sometimes containing evaporites eastward the ramp passes to the reefal pelagian platform extending as far as lampedusa two main sedimentary cycles are distinguished 1 an early messinian siliciclastic retrogradational then oolitic bioclastic progradational cycle beni khiar formation and lower oued bel khedim formation 2 a late messinian brackish to continental cycle that probably accumulated in rapidly subsiding lagoons cued el bir formation and upper oued bel khedim formation the tunisian early messinian cycle is partly eustatically controlled but the late messinian cycle cannot be confidently correlated to other well known messinian series because of tectonic movements the lower messinian deposits of tunisia are also characterized by abundant suspension feeding organisms molluscs and bryozoans and rare corals calcareous algae echinoids and larger benthic foraminifers the proposed palaeoenvironmental model shows that the lower messinian ramp of tunisia was located on a current protected margin and subjected to continent derived sediment and nutrient supply eastward nutrient influx diminished and a shallow water isolated carbonate platform with coralgal facies developed between the western and the eastern mediterranean basins the main hydrological connection between these two basins occurred through a narrow seaway situated to the northeast of the pelagian platform south of sicily and malta

petrous bone diagenesis a multi analytical approach abstract the discovery of petrous bone as an excellent repository for ancient biomolecules has been a turning point in biomolecular archaeology especially in adna research but excessive and uncontrolled sampling could result in loss of this valuable resource for future research this study reports on the histological optical microscopy physical ftir atr elemental chn and biochemical collagen and dna analysis preservation of 15 human petrous bones spanning from the c 2100 bce to 1850 ce through the combined application of a number of diagenetic parameters general histological index infrared splitting factor carbonate phosphate ratio amide phosphate ratio col wt c n and c n of whole bone and collagen endogenous dna we provide new insights into petrous bone micromorphological characteristics and diagenesis and new evidence to enhance screening practices for adna and collagen analysis

contextualising the dead combining geoarchaeology and osteo anthropology in a new multi focus approach in bone histotaphonomy abstract histotaphonomy has become an important area of research in funerary archaeology it focuses on diagenetic alterations in bone microstructure and the reconstruction of post mortem processes microbial bioerosion is the most common diagenetic change observed in archaeological bone and its probable causes have been the subject of ongoing discussions this paper presents a new integrative approach that combines methods from physical anthropology and geoarchaeology the aim is to contextualise samples in regard to their sedimentary milieu sediment type the sedimentation processes they underwent and the specific archaeological features they originate from the analysis is based on 208 human and animal skeletal fragments from the late la tene site of basel gasfabrik recovered from various feature types and embedded in different sediments both 80 m and 30 m thin sections were graded semi quantitatively on a scale of 0 or 1 to 5 in regard to bacterial attack bai wedl tunnels wti cyanobacterial attack cai the formation of cracks cri the collagen content coi and thermal alterations hei our results evinced no correlations between the intensity of bacterial attack and sediment types or sedimentation processes respectively we therefore deduce that bacterial degradation of bone is mainly caused by endogenous gut bacteria wedl tunnels on the other hand are chiefly found in bones from exposed surfaces bone collagen content as measured by birefringence is dependent on a variety of factors with thermal alteration being among the most important unlike the 80 m sections used in anthropological investigations the 30 m thin sections typically utilized in geoarchaeological analyses permitted a reliable distinction of microbial bioerosion types our context oriented histotaphonomic approach allows detailed conclusions on the causes of microbial bioerosion in bone moreover it provides an important tool for reconstructing the post mortem biographies of human and animal remains especially in regard to multi stage mortuary practices and the analysis of sedimentation processes thus this novel approach generates a wealth of information from individual skeletal elements as well as from bone fragments embedded in soil samples

palaeoenvironmental changes across the danian selandian boundary in the north sea basin abstract the danian selandian boundary 60 ma marks the cessation of 40 million years of carbonate deposition in the north sea basin and a shift to siliciclastic deposition on the basis of variations in lithology benthic and planktonic foraminifera and calcareous nannofossils in three cores from storebaelt in the eastern part of the north sea basin we have reconstructed the palaeoenvironmental changes across the boundary the benthic foraminiferal faunas belong to the midway type fauna they are extremely rich and more than 260 taxa have been recognized q mode cluster analysis groups the benthic assemblages into four biofacies which correspond fairly closely to lithological units correlation of the storebaelt records with marine palaeorecords from the danish basin and the north sea basin indicate that the transformation of the north sea from a carbonate to a siliciclastic basin occurred in four steps separated by relatively long stable periods the most important external factors involved in the change are firstly a drop in the relative sea level during the late danian leading to the disappearance of bryozoans from the north sea basin and to non deposition and erosion in many areas secondly coinciding with the danian selandian boundary an uplift of the scotland shetland area resulting in a massive input of siliciclastic deposits to the north sea basin thirdly during the early selandian inversion of the sorgenfrei tornquist zone and mesozoic basins in the southern and eastern part of the north sea basin resulted in a huge influx of reworked cretaceous chalk and an almost complete stop of carbonate production finally later in the early selandian in connection to a general sea level rise and a reduction in the gateway between the north sea basin and the tethys sea the sea bottom conditions became colder and more acidic this resulted in partial dissolution of the carbonates and the deposition shifted from marl to clay comparison with records from the western pyrenees the nile basin and the eastern north america suggests that sea level changes across the danian selandian boundary are primarily of eustatic nature

diagenesis in bone and enamel apatite carbonate the potential of density separation to assess the original composition abstract this paper presents a new approach to the isotopic measurement of diagenetically altered archaeological bone apatite carbonate we describe how the existing differential dissolution method may be combined with a new approach to remove diagenetically reformed material on the basis of its greater specific gravity we show that heavier more diagenetically altered fraction has a higher altered 13 c and also increased crystallinity within one individual in addition we proposed one potential tool to check the validity of bone carbonate by comparing bone collagen enamel carbonate and bone carbonate values of 13 c and radiocarbon content from the same individual in the case of danebury cattle we estimated the biogenic 13 c apa value for dc83 and dc89 although it is still difficult to overcome diagenesis in order to meet the expected value which is shown to be 1 9 dc83 and 3 5 dc89

use of micro computed tomography imaging and porosity measurements as indicators of collagen preservation in archaeological bone abstract collagen isolated from archaeological bone is a common material for radiocarbon dating stable isotope analysis and zooarchaeology by mass spectrometry zooms however not all bones contain extant collagen leading to unnecessary destruction of unproductive bones and wasted laboratory time and resources an aim of this research is to study bone diagenesis particularly collagen destruction in an effort to develop a minimally destructive method for identifying bones with high collagen content in a multi method study of variably preserved bones from etton cambridgeshire uk we examined material properties of neolithic cattle and sheep bones including porosity surface area and elemental composition micro computed tomography microct is an imaging technique that furnishes three dimensional images of mineralized materials such as bone cortical bone porosity the percentage of total bone volume consisting of empty space as calculated using microct can act as a proxy for bone collagen preservation in general bones with high cortical porosity are unlikely to contain sufficient collagen for further analysis bones with apparently low cortical porosity have a more varied range of collagen preservation bone samples with low porosity and no extant collagen often contain micropores with a diameter of 10 nm or less that cannot be seen in microct images but are apparent in pore size distributions measured by mercury porosimetry and indicated by high surface areas measured by nitrogen adsorption furthermore a re evaluation of light induced breakdown spectroscopy data from this same assemblage confirms that ratios of calcium to fluorine may likewise indicate the state of diagenesis

bone preservation in hayonim cave israel a macroscopic and mineralogical study abstract understanding the cause of patchy bone distributions in archaeological sites requires that one distinguish bone decomposition in place from empty areas where bones were never present marked horizontal variations in bone abundance are found in the thick mousterian layer e of hayonim cave a large paleolithic site in northern israel infra red analyses of minerals in the sediments identify zones of advanced diagenesis and decomposition alongside zones whose chemistry clearly favoured the preservation of bones and wood ash these differences adhere closely to the distribution of recognizable bones in the deposits indicating that spatial variation in bone abundance is essentially a product of differential preservation conditions however the few bones present in the bone poor units are in surprisingly good condition the higher degree of abrasion damage and more random orientations of these bones indicate that small amounts of recent material were introduced into older layers by small burrowing animals and perhaps localized trampling the ratio of post mousterian to mousterian artifacts in layer e and the numeric contrasts in bone abundance among stratigraphic units indicate that time averaging from mechanical intrusion was quantitatively unimportant 2 5 throughout this 2 4 m thick layer our findings support karkanas et al 2000 suggestion that bone and ash mineral diagenesis in caves follow step wise rather than gradual transformations in geological time good preservation environments can be distinguished from poorer ones on the basis of mineral assemblages in sediments and deposits that once contained bone and wood ash can be identified long after the visible traces of these materials have disappeared

characterisation of post depositional taphonomic processes in the accumulation of mammals in a pitfall cave deposit from southeastern australia mceachern s deathtrap cave g49 50 is a classic pitfall trap located in southeastern australia which has been collecting terrestrial animals since the late quaternary dispersal and breakage of fossil bone elements are recognised as dominant taphonomic processes the sedimentary sequence contained within the cave consists of an upper and lower sequence where two distinct types of bone modification are identified the degree of bone breakage gradually increases with depth and is attributed to sediment compression and trampling minor in situ breakage has occurred as a result of rock fall and or trampling bone dispersal processes are indicated by a deficit in element representation required to account for whole skeletons based on mni calculations bone elements that are easily transportable by flowing water have a low frequency of representation in the sedimentary sequence in the cave floor bone lag deposit shallow intermittent flowing water is suggested by the dominance of transverse limb orientations and the low frequency of stable orientations that only occur in the most sensitive flow indicators e g pelves

patterns of diagenesis in bone i the effects of site environments abstract we have measured a suite of diagenetic parameters for several populations of archaeological bones buried in a number of northwest european sites since the last ice age these are the structural damage due to microbes changes in bone micro and macro porosity protein content a measure of the crystallinity of hydroxyapatite as reflected in the phosphate infra red spectrum peak splitting and a measure of the carbonate content as given by the ratio of carbonate to phosphate infra red absorption peaks the results provide a database that clearly characterises the patterns which are often site dependent of diagenetic change in buried bone our main conclusions are that individual site hydrology appears to have a strong influence on the outcome of bone preservation and that porosity is the most effective single diagenetic parameter which both determines and reflects the preservation of bone in the burial environment

geochemical study of vertebrate fossils from the upper cretaceous santonian csehbanya formation hungary evidence for a freshwater habitat of mosasaurs and pycnodont fish abstract the diverse vertebrate remains from the upper cretaceous freshwater settings at iharkut hungary contain two fossil groups pycnodontiformes fish and mosasauridae that are almost exclusively known from marine palaeo environments hence their appearance in alluvial sediments is very unusual trace element and isotope compositions of the remains have been analyzed to investigate the taphonomy and the ecological differences among the different fossil groups present at iharkut all examined fossils have undergone post depositional diagenetic alteration which resulted in high concentrations of ree u and fe together with almost complete homogenization of 18oco3 values similar ree patterns in different fossils suggest a common origin for all remains hence the discovered species most likely lived in the same local ecosystem despite partial diagenetic overprinting the 18opo4 values of the fossils indicate sufficient taxon specific isotopic diversity to permit some broad conclusions on the palaeo environment of the fossils in particular it is apparent that the isotopic composition of the pycnodontiformes fish and mosasauridae remains is most compatible with a freshwater palaeo habitat and incompatible with a marine palaeo environment in addition the sr concentration and isotope data indicate that the pycnodontiformes and mosasauridae likely lived predominantly in a freshwater environment and were not simply occasional visitors to the iharkut river ecosystem regarding other fossil groups high 18opo4 values of alligatoroidea and iharkutosuchus teeth suggest that these small crocodile species might have inhabited swamps and ponds where the water was relatively rich in 18o due to evaporation

modern carbonate and terrigenous clastic sediments on a cool water high energy mid latitude shelf lacepede southern australia the wide lacepede shelf and narrow bonney shelf are contiguous parts of the south eastern passive continental margin of australia the shelves are open generally deeper than 40 m covered by waters cooler than 18 c and swept by oceanic swells that move sediments to depths of 140 m the lacepede shelf is proximal to the delta of the river murray and the coorong lagoon shelf and upper slope sediments are a variable mixture of holocene and late pleistocene quartzose terrigenous clastic and bryozoa dominated carbonate particles bryozoa grow in abundance to depths of 250 m and are conspicuous to depths of 350 m they can be grouped into four depth related assemblages coralline algae the only calcareous phototrophs are important sediment producers to depths of 70 m active benthic carbonate sediment production occurs to depths of 350 m but carbonate sediment accumulation is reduced on the open shelf by continuous high energy conditions the shelf is separated into five zones the strandline is typified by accretionary sequences of steep shoreface beach and dune carbonate siliciclastic sediments similar shoreline facies of relict bivalve limestone cobble ridges are stranded on the open shelf the shallow shelf c 40 70 m deep is a wide extremely flat plain with only subtle local relief it is a mosaic of grainy quartzose palimpsest facies which reflect the complex interaction of modern bioclastic sediment production dominated by bryozoa and molluscs numerous highstands of sea level over the last 80 000 years modern mixing of sediments from relatively recent highstands and local introduction of quartz rich sediments during lowstands the middle shelf c 70 140 m deep is a gentle incline with subtle relief where holocene carbonates veneer seaward dipping bedrock clinoforms and local lowstand beach complexes carbonates are mostly modern uniform clean coarse grained sands dominated by a diverse suite of robust to delicate bryozoa particles produced primarily in situ but swept into subaqueous dunes the deep shelf edge c 140 250 m deep is a site of diverse and active bryozoa growth resulting accumulations are characteristically muddy and distinguished by large numbers of delicate branching bryozoa the upper slope between 250 and 350 m depth contains the deepest platform related sediments which are very muddy and contain a low diversity suite of delicate branching cyclostome bryozoa this study provides fundamental environmental information critical for the interpretation of cenozoic cool water carbonates and the region is a good model for older mixed carbonate terrigenous clastic successions which were deposited on unrimmed shelves

variability of bone preservation in a confined environment the case of the catacomb of sts peter and marcellinus rome italy most of the studies investigating the diagenetic trajectory of fossil bones focus on open air sites and very little work have been published in confined environments such as catacombs while the stable thermal history of catacombs should favor bone preservation the accumulation of corpses over a short period of time could favor their destruction the aim of this study is to describe the diagenetic trajectory of 128 human bone samples coming from six different burial chambers of the catacomb of sts peter and marcellinus sspm rome italy a multi proxy approach was undertaken to provide an assessment of the molecular preservation as well as a direct record of the isotopic composition itself collagen yield carbon and nitrogen abundances c n ratio ft ir based collagen and carbonate contents and crystallinity index radiocarbon dating and stable isotope analysis of bone collagen and carbonate indicate that both the mineral and the organic fractions are impacted by diagenesis to various degrees and that bones originating from the small burial chambers are more affected than those coming from the large ones while some of the bones were strongly recrystallized the impact of bone diagenesis on the stable isotope values of bone carbonate was limited comparison with contemporary sites from the latium showed that conditions prevailing in catacombs seem overall to favor rather than disadvantage bone preservation

diagenetic changes on bone histology of quaternary mammals from a tropical cave deposit in southeastern brazil abstract karst caves are suitable environments for the accumulation and preservation of fossils cave deposits are often complex and the environmental conditions within cave sites result from intricate interactions between various biological physical and chemical factors however it is not fully understood how the complexity of the environmental conditions of caves influences bone diagenesis the study of the initial stages of bone diagenesis depends to a large extent on understanding the changes in the bone histology to contribute to this issue we examine a set of postmortem changes affecting the bone histology of quaternary mammals that accumulated naturally in locus 2 a pitfall site in cuvieri cave located in the tropical region of brazil our analyses show that bones deposited in caves may be subject to a peculiar set of environmental conditions that in tropical regions may prevent the preservation of bone histological structure the effect of diagenetic processes on the bones differs depending on the taphonomic stage of the bone and the diagenetic alterations appear to have influenced each other the deposition of bioclasts following the entrapment of individuals in locus 2 favours the proliferation of bacteria on bones and appears to be important in directing the diagenetic alteration the hydrological regime of the cave that is recharge with potential phases of higher humidity also is important in directing the diagenetic alteration and further decreased the preservation potential of the bone microstructure the formation of macroscopic and microscopic cracks related to bone weathering in caves shows that the taphonomic processes peculiar to these environments are poorly understood highlighting the need for more research to be conducted on cave taphonomy

light at the end of the tunnels the origins of microbial bioerosion in mineralised collagen abstract microbial bioerosion in all its manifestations is one of the major factors determining the long term survival of archaeologically and environmentally important artefacts and ecofacts made from mineralised collagen bones antler teeth and ivory the bone diagenesis literature contains extensive descriptions of different morphologies and classifications of microbial bioerosion microscopical focal destruction wedl tunnels linear longitudinal budded and lamellate tunnelling etc but the causative agents remain to be discovered palaeontologists are in a similar situation when describing ichnofossils where bioerosion is classified by its characteristic morphology and only tentatively assigned to specific causes in archaeological bones wedl tunnels have traditionally been ascribed to fungi but a re examination of wedl s original paper and subsequent literature has shown that all the early specimens examined came from aquatic environments and that euendolithic microflora cyanobacteria or chlorophytes might have been responsible these microorganisms are known to tunnel into marine shells linear longitudinal budded and lamellate tunnelling have all been ascribed to bacteria however analyses using a combination of backscatter sem bsem and mercury intrusion porosimetry hgip of bones excavated from terrestrial soils suggest that the various tunnelling morphologies described by earlier researchers are actually all manifestations of a single architecture the differences arising from the inherent variability of bone microstructure and the hydrology of the burial environment an examination of the bsem and hgip data also indicates that the bacteria responsible may spread through dead bone tissues by expanding the canalicular network or dentinal tubules in teeth rather than creating new tunnels long term field burial experiments using de fleshed cow bone specimens have now demonstrated that bacterial tunnelling develops over decades rather than months as was previously thought even in warm tropical soils this has obvious implications for the origin of the bacteria responsible soil bacteria versus endogenous gut bacteria since the bone specimens were quickly isolated from gut contents although no attempt is made here to identify a specific organism or organisms responsible for tunnelling in terrestrial archaeological bones a tentative model is proposed for how cycles of wetting and drying or changes in local dissolved oxygen levels could lead a common gram positive soil bacterium to produce the pattern of bacterial bioerosion seen in exhumed bones this soil organism may act in a similar way to staphylococcus aureus which proliferates in living bone causing osteomyelitis by infiltrating and enlarging the canalicular network

bone diagenesis in the european holocene i patterns and mechanisms diagenetic changes in archaeological bone are known to influence the data derived from such material and have thus been the subject of numerous studies a number of general trends have been observed but many of the processes that occur are still not fully understood we present here the analysis of 195 bones excavated from 32 sites in five different countries from eurasia characterized using 10 simple diagenetic parameters the results reveal that most european holocene archaeological bone can be categorized by only four main diagenetic states related to three distinct trajectories that describe more than 60 of the variation in these parameters given the potential amount of variation in the dataset the small number of diagenetic pathways is surprising but highlights the large importance of a few key factors that influence bone diagenesis mercury intrusion porosimetry is a key technique for identifying modes of degradation

measurements and relationships of diagenetic alteration of bone from three archaeological sites four diagenetic parameters have been chosen to represent the state of diagenesis of bone buried on archaeological sites they are histological preservation protein content crystallinity and porosity how these parameters are measured is described and results from populations of bones from three different sites are presented the results show the extent and variation in the degree of change both within a site and between sites in particular the correlations between diagenetic parameters are examined which give clues about the processes which cause alteration the value of porosity determinations both at the intercrystalline level and at coarser levels in revealing the degree of diagenetic change in bone and in underlying the dynamics of the interaction between buried bone and the surrounding water is stressed the data also indicate but are too restricted to prove the following microbiological attack is generally complete within less than 500 years substantial levels of protein may remain in bone after maximal micromorphological alteration loss of protein appears to be independent of other diagenetic change the correlated lose of microporosity with increase of crystallinity suggests these changes may arise from the dissolution perhaps with subsequent recrystallization of the smallest hydroxyapatite crystallites

bone diagenesis variability among multiple burial phases at al khiday sudan investigated by atr ftir spectroscopy abstract in this study the diagenetic pathways of archaeological human bones are investigated through fourier transform infrared spectroscopy in attenuated total reflection mode atr ftir archaeological excavations at al khiday 16 d 4 site khartoum sudan revealed a multi stratified cemetery with distinct burial phases chronologically attributed to different periods spanning from the early holocene to the beginning of the 1st millennium ce atr ftir measurements are carried out on a set of 56 bone samples representative of each burial phase parameters related to collagen content and to bioapatite crystallinity and structural carbonate are calculated from infrared spectra in order to monitor the types and extent of diagenetic alteration to assess the preservation state of bones and to define the alteration processes occurring during burial a new method is here developed to quantify the amount of secondary calcite and to remove its contribution to the infrared spectrum when interfering with the signal of structural carbonate from bioapatite considering the wide span of time covered by the archaeological record the variability of bones alteration among burial phases is related to the climatic changes occurring in central sudan during the holocene the more humid environment occurring in the early holocene characterised by higher precipitation rates seasonal swamps and palaeo lakes progressively changed towards drier conditions until the current arid climate of the sub saharan belt the change of palaeoenvironmental and local burial conditions over time differently influenced the types and extent of diagenetic processes affecting bones during burial in this research are also discussed advantages and disadvantages of atr ftir spectroscopy with respect to the more established ftir spectroscopy in transmission mode

origin of a cool water oligo miocene deep shelf limestone eucla platform southern australia the abrakurrie limestone is an areally extensive bryozoan rich unit within the eucla platform a tertiary carbonate shelf which caps the central part of the southern australian continental margin the onshore portion the topic of this study has been exposed since middle miocene time and lies beneath the nullarbor plain the rocks are fine sand to granule sized calcarenites composed of bryozoans bivalves benthic foraminifera and echinoids with lesser numbers of brachiopods solitary corals and serpulids they conspicuously lack significant numbers of planktonic foraminifera and coralline algae most bryozoan remains are from delicate branching cyclostomes although delicate branching robust branching foliose fenestrate multilaminar encrusting and free living cheilostomes are variably abundant in specific units the poorly lithified sequence is punctuated by well cemented layers with erosional tops which are interpreted as hardgrounds the limestone is interpreted as a cool water deep shelf deposit which accumulated in water depths generally greater than 50 m on the inner part of the eucla platform a model which involves deposition and cementation on a carbonate shelf swept by open ocean swells is proposed to explain the style of sedimentation the shelf is envisaged as partitioned by the depth of the zone of wave abrasion sediments were produced throughout but accumulated only below this depth when the seafloor was above this depth it was an environment of cementation and erosion the vertical sequence correlates in a general way with the global sea level model for the mid cenozoic while accumulation rates for southern australian carbonates are similar to rates of cool water carbonate deposition elsewhere c 2 5 cm kyr 1 the rate of abrakurrie accumulation is much less suggesting that significant time periods are represented by the hardgrounds

palaeoenvironmental changes at the tortonian messinian boundary a deep sea sedimentary record of the eastern mediterranean sea abstract in the eastern mediterranean the island of crete offers excellent exposures of upper miocene marine deposits three detailed sections of the tortonian messinian sedimentary succession were measured and sampled in three different basins from west to east chania heraklion and sitia the biostratigraphic analysis based on planktonic foraminifera yielded ages ranging from about 7 58 to 6 72 ma nine bioevents were also recognised and provided good correlations between the studied sections rich benthic faunas commonly occurring together with fish otoliths have furthermore been recovered and analysed foraminifera mollusc mostly bivalves bryozoans and ostracods the autochthonous assemblages suggest deposition at middle upper bathyal depths at the base and outer inner shelf in the upper parts of the sections the shallowing upward trend observed in all three sections is accompanied by the occurrence in a few messinian levels of allochthonous fossils transported downslope and deposited in deep water environments dysoxic episodes were moreover recorded in some beds mostly in the messinian a comparison with other coeval basins and faunas indicates that similar palaeoenvironmental conditions predominated throughout the mediterranean sea during the late miocene this is consistent with the postulate of open connections through marine corridors between the mediterranean and the atlantic presumably until late in the messinian

diagenesis of archaeological bone and tooth an understanding of the structural complexity of mineralised tissues is fundamental for exploration into the field of diagenesis here we review aspects of current and past research on bone and tooth diagenesis using the most comprehensive collection of literature on diagenesis to date environmental factors such as soil ph soil hydrology and ambient temperature which influence the preservation of skeletal tissues are assessed while the different diagenetic pathways such as microbial degradation loss of organics mineral changes and dna degradation are surveyed fluctuating water levels in and around the bone is the most harmful for preservation and lead to rapid skeletal destruction diagenetic mechanisms are found to work in conjunction with each other altering the biogenic composition of skeletal material this illustrates that researchers must examine multiple diagenetic pathways to fully understand the post mortem interactions of archaeological skeletal material and the burial environment

bone diagenesis in arid environments an intra skeletal approach bone trace element content and isotopic composition are closely related to human nutrition the investigation of archaeological bone geochemistry can help us to better understand the relationship between past populations and their environment alongside cultural practices as inferred from dietary reconstruction however dietary in formation may be altered post mortem by diagenetic processes in soil in this study bone mineralogy ca p sec ondary minerals organic matter content and bone apatite crystallinity histology element content mg na f sr ba mn fe la ce and u and stable isotope composition 13cand 18o carbonate were investigated at the intra individual scale in order to understand the effects of diagenesis on skeletons buried in different saharo sahelian environments between 10 to 18 bone samples were taken from 4 neolithic skeletons excavated in the mauritanian dhar oualata and nema and in the daounas mali additionally the enamel of two third molar teeth was also analysed from each skeleton for comparison with bone the results show that the four skeletons buried in the same desert climate area all exhibited different degrees of diageneticmodification relatedto localtaphonomic conditions highly drainedand periodically flooded environments generated substantial bone bacterial damage low to moderate apatite crystallinity and secondary minerals in bone pores bone trace element content and isotopic composition were more diagenetically affected than in bones from skeletons buried in a drier environment which display little bioerosion high apatite crystallinity and the absence or late precipitation of secondary minerals in their bone pores intra skeletal variability of the geochemical composition and the comparison of geochemical data from bones and teeth enables the approximation of ante mortem bone trace element and stable isotope compositions using the best preserved bones from each skeleton

evolution of a miocene carbonate shelf northern apennines italy revealed through a quantitative compositional study abstract the evolution of the miocene san marino carbonate shelf torriana outcrop developed on the accretionary prism of the northern apennines has been interpreted through a stratigraphic and compositional study modal analysis allowed to quantify the framework components and to identify four microfacies through which the main steps of the carbonate ecosystem were traced the healthy phase of the carbonate shelf dominated by bryozoans and echinoids originated in a high energy transgressive setting and evolved during a warm period characterized by a progressive increase of nutrients the transitional stage is marked by a reduction of carbonate productivity and by terrigenous intermittent pulses associated with bioclast fragmentation the drowning succession corresponds to deepening upward facies formed by fine grained hybrid arenites to sandy marls with abundant planktonic foraminifera glauconitic grains and clay matrix the demise of the carbonate shelf might have resulted from a combination of regional and global factors that interplayed controlling the detrital input the nutrient budget and the deepening of the basin synsedimentary tectonics triggered subsidence of the basin and enhanced terrigenous discharge moreover the superposition of paleoclimatic and paleoceanographic events monterey and middle miocene climate optimum could have contributed with the intense weathering and remarkable detrital and nutrients supply

bone diagenesis new data from infrared spectroscopy and x ray diffraction abstract this paper combines non destructive high resolution fourier transform infrared spectroscopic techniques attenuated total reflectance in the mid infrared atr and diffuse reflectance in the near infrared nir with x ray diffraction and rietveld analysis in the study of bone diagenesis sixty fossil bones from two upper miocene sites in greece pikermi and chalkoutsi and one upper pleistocene site in cyprus aghia napa are investigated in comparison to various mineral and biological apatites diagenetic trends common to all these sites include a subtle but systematic decrease of the unit cell volume and a axis of carbonate hydroxylapatite as well as a parallel increase of the coherence length along the c axis chemometric modelling reveals that the changes in the unit cell and the coherence length are highly correlated to and can be predicted on the basis of the atr spectra besides using chemometrics as a convenient predictive tool we have been able to identify that the correlation with the xrd data is primarily based on the intensity of infrared bands at 577 865 and 1092 cm 1 as well as on the position of the 1 phosphate mode at ca 960 cm 1 these structural changes constitute the vibrational signature of diagenesis throughout our set of bone samples and can be accounted for by the stabilization of a distorted co 3 2 species in the b sites of apatite and to a lesser extent by the substitution of oh by f nir spectroscopy allowed for the identification of a well defined h 2 o species absorbing at 5318 and 7240 cm 1 this species is labile appears to characterize mostly biogenic apatite and is therefore considered to be chemisorbed on the surface of the crystallites

cretaceous evolution of the central asian proto paratethys sea tectonic eustatic and climatic controls the timing and mechanisms of the cretaceous sea incursions into central asia are still poorly constrained we provide a new chronostratigraphic framework based on biostratigraphy and magnetostratigraphy together with detailed paleoenvironmental analyses of cretaceous records of the proto paratethys sea fluctuations in the tajik and tarim basins the early cretaceous marine incursion in the western tajik basin was followed by major marine incursions during the cenomanian ca 100 ma and santonian ca 86 ma that reached far into the eastern tajik and tarim basins these marine incursions were separated by a turonian coniacian ca 92 86 ma regression basin wide tectonic subsidence analyses imply that the early cretaceous sea incursion into the tajik basin was related to increased pamir tectonism we find that thrusting along the northern edge of the pamir at ca 130 90 ma resulted in increased subsidence in a retro arc basin setting this tectonic event and coeval eustatic highstand resulted in the maximum observed geographic extent of the sea during the cenomanian ca 100 ma the following turonian coniacian ca 92 86 ma major regression driven by eustasy coincides with a sharp slowdown in tectonic subsidence during the late orogenic unloading period with limited thrusting the santonian ca 86 ma major sea incursion was likely controlled by eustasy as evidenced by the coeval fluctuations in the west siberian basin an early maastrichtian cooling ca 71 70 ma potentially connected to global late cretaceous trends is inferred from the replacement of mollusk rich limestones by bryozoan and echinoderm rich limestones

bone diagenesis at the micro scale bone alteration patterns during multiple burial phases at al khiday khartoum sudan between the early holocene and the ii century ad abstract histological analysis is widely applied to archaeological and fossil bones in order to identify diagenetic changes in bone microstructure diagenetic processes affecting bones from the body deposition to the discovery strongly depend on environmental conditions therefore the study of diagenetic alterations provides valuable information on the taphonomic history of bones and on their burial environment histological analysis was performed on 58 samples of human compact bone found at al khiday khartoum sudan a multi stratified archaeological site that revealed a cemetery with distinct burial phases dating from the early holocene to the ii century ad the well defined archaeological context provides a set of bone samples belonging to the same site but buried in different phases and under different environmental conditions central sudan was characterised by a humid environment with seasonal swamps and palaeo lakes in the early holocene while in the ii century ad the environmental conditions were more similar to the current arid climate of the sub saharan belt scanning electron microscopy sem and high resolution x ray computed micro tomography ct analysis revealed extensive bacterial and fungal attack and secondary phases precipitation and dissolution in the samples the analysis of textural relationships between each diagenetic feature enabled to establish a relative chronological sequence of events acting during burial moreover different patterns of diagenetic alterations were observed for burial phases of different ages proving a strong relationship between diagenesis and environmental conditions

patterns of diagenesis in bone ii effects of acetic acid treatment and the removal of diagenetic co32 abstract archaeological bones of varying preservation have been treated with 0 1 m acetic acid in order to investigate the effect on structural and chemical alterations caused by diagenesis acetic acid is commonly used as a cleaning agent for removing diagenetic carbonate from bone and enamel in an attempt to recover original biogenic signals for use in dietary and14c dating studies diagenetic parameters were measured before and after treatment on a range of archaeological bones with good and bad preservation histological preservation defined the behaviour of the correlating parameters where correlation coefficients between carbonate content and crystallinity microporosity and macroporosity increased significantly after treatment for histologically well preserved material acetic acid is effective at returning carbonate content to around that of modern bone where bone is extensively damaged by micro organisms loose diagenetic material can be removed but a fraction largely composed of hypermineralized bioapatite remains which we believe cannot be reliably used to obtain accurate biological signals

examining histology to identify burned bone abstract early research suggests that examination of the microscopic internal structure is a valid method for distinguishing burned from unburned bone in the archaeological record this study compares burned and unburned modern bones with archaeological bones from sibudu cave ca 60 000 years ago and cave of hearths over 200 000 years ago to more fully describe the heat induced histological changes to bone we also explore the effects of diagenesis on those changes to determine if histological evidence of burning preserves through fossilisation and diagenetic processes and can be successfully used to identify ancient burning application of this technique can help in addressing various issues including the origins of controlled use of fire and understanding animal butchery and disposal