stable isotopes δ18o and δ13c trace and minor element compositions of recent scleractinians and last glacial bivalves at the santa maria di leuca deep water coral province ionian sea special issue the aplabes programme physical chemical and biological characterization of deep water coral ecosystems from the ionian sea mediterranean 16 pages 13 figures 3 tables 2 appendix

paleoclimatic implications of middle wisconsinan pollen and a paleosol from the purcell trench south central british columbia a paleosol and organic rich horizons occur in bessette sediments near meadow creek south central british columbia the paleosol is at least 42 000 years old and formed on a paleoslope adjacent to some precursor to meadow creek on higher parts of the paleoslope the soil developed under locally dry conditions and influxes of eolian material a regosol formed near the base of the paleoslope marginal to a floodplain pollen assemblages from the organic rich horizons are grouped into two assemblage zones mc 1 approximately 42 000 years old is dominated by arboreal pollen mainly picea mc 2 approximately 34 000 years old is dominated by picea in conjunction with significant amounts of tsuga heterophylla paleoclimatic implications of the assemblages are that temperatures 42 000 years ago were approximately 3 c cooler than present but by 34 000 years ago had ameliorated and were similar to or slightly cooler than present

first observations of the cold water coral lophelia pertusa in mid atlantic canyons of the usa abstract the structure forming cold water coral lophelia pertusa is widely distributed throughout the north atlantic ocean and also occurs in the south atlantic north pacific and indian oceans this species has formed extensive reefs chiefly in deep water along the continental margins of europe and the united states particularly off the southeastern u s coastline and in the gulf of mexico there were however no records of l pertusa between the continental slope off cape lookout north carolina nc 34 n 76 w and the rocky lydonia and oceanographer canyons off cape cod massachusetts ma 40 n 68 w during a research cruise in september 2012 l pertusa colonies were observed on steep walls in both baltimore and norfolk canyons these colonies were all approximately 2 m or less in diameter usually hemispherical in shape and consisted entirely of live polyps the colonies were found between 381 m and 434 m with environmental observations of temperature 6 4 8 6 c salinity 35 0 35 6 and dissolved oxygen 2 06 4 41 ml l 1 all of which fall within the range of known l pertusa distributions all colonies were observed on vertical walls or underneath overhangs in areas of high current which differs from observations further south where l pertusa colonizes rocky ledges and outcroppings often forming large bioherms we discuss observations from baltimore and norfolk canyons in the context of the known distribution of this species in the north atlantic

pollen and lignin records of late quaternary vegetation lake washington analyses of lignin oxidation products and pollen for an 11 meter core from lake washington provide independent but similar reconstructions of the late quaternary vegetation in the puget lowland an exception is in sediments of the late pleistocene where pollen percentages and influx values suggest conifer forest whereas lignin compositions suggest a treeless source region this dissimilarity appears to result from different major provenances eolian transport of pollen to the lake from adjacent or downstream drainage basins as opposed to fluvial transport of lignified plant debris only from the lake washington drainage basin

ploughing the deep sea floor bottom trawling is a fishing technique whereby heavy nets and gear scrape along the sea bed and is shown here to disturb sediment fluxes and modify the sea floor morphology over large spatial scales the direct impact of bottom trawling on local fish populations has received much attention but trawling also affects other aspects of the ocean environment this paper shows that bottom trawling a commercial practice in which heavy nets and gear are dragged along the ocean floor induces sediment reworking and erosion causing the gradient of the sea floor to become smoother over time this reduces the morphological complexity of deep sea environments the authors draw parallels between the effects of bottom trawling at sea and intensive agriculture on land with the important difference that on land ploughing takes place once or twice a year whereas at sea bottom trawling can be a frequent occurrence bottom trawling is a non selective commercial fishing technique whereby heavy nets and gear are pulled along the sea floor the direct impact of this technique on fish populations1 2 and benthic communities3 4 has received much attention but trawling can also modify the physical properties of seafloor sediments water sediment chemical exchanges and sediment fluxes5 6 most of the studies addressing the physical disturbances of trawl gear on the seabed have been undertaken in coastal and shelf environments7 8 however where the capacity of trawling to modify the seafloor morphology coexists with high energy natural processes driving sediment erosion transport and deposition9 here we show that on upper continental slopes the reworking of the deep sea floor by trawling gradually modifies the shape of the submarine landscape over large spatial scales we found that trawling induced sediment displacement and removal from fishing grounds causes the morphology of the deep sea floor to become smoother over time reducing its original complexity as shown by high resolution seafloor relief maps our results suggest that in recent decades following the industrialization of fishing fleets bottom trawling has become an important driver of deep seascape evolution given the global dimension of this type of fishery we anticipate that the morphology of the upper continental slope in many parts of the world s oceans could be altered by intensive bottom trawling producing comparable effects on the deep sea floor to those generated by agricultural ploughing on land

hard and soft bottom thanatofacies from the santa maria di leuca deep water coral province mediterranean thanatofacies and the skeletonized components of the living facies from which they originate have been studied from the santa maria di leuca sml deep water coral mound province faunal analysis was carried out by means of bottom sampling and underwater video observations taking into account all benthic taxonomic groups mostly corals molluscs serpulids bryozoans ostracods foraminifers and barnacles which permitted recognition of six different facies these thanatofacies are easily distinguishable and appear to be largely corresponding and overlapping with related living facies some occur in mound areas others in the intermound ones they are as follows the framework building coral facies fc characterised by colonial corals mostly madrepora oculata the coral rubble facies cr with proximal and distal aspects characterised by large to small sized and densely to loosely packed coral fragments the solitary coral facies sc dominated by different species depending on the availability and dimensions of hard exploitable surfaces the gryphus and isidella facies gi in relatively coarse grained bottoms the mollusc mud facies mm and the foraminifer mud facies fm in comparably homogeneous silty bottoms facies distribution and spatial variability are discussed in relation to hydrology and sea floor topography furthermore the sml facies are compared with living facies from the present day mediterranean and pleistocene sediments of the same area data on bioclastic assemblages can serve for comparison with other recent aphotic non tropical carbonates

reprint of on and off the beaten track megafaunal sessile life and adriatic cascading processes abstract valuable megafaunal sessile assemblages in the southern adriatic basin present a western eastern asymmetric distribution this is particularly evident when considering cold water coral cwc communities with most diverse and abundant live corals to be found along the western side on the contrary only spotty occurrences are documented in the eastern side and at times only in a sub fossil state we hypothesize that this asymmetry might derive from differential exposure of the adriatic floor to polarized hydrological processes in such a perspective vigorous albeit a periodical flushing of deep sea bottoms at times of cascading processes could be beneficial to sessile deep sea benthic communities by reinforcing the north adriatic dense water naddw contrasting excess silting and by enhancing the trophic web although no experimental evidence has been yet produced to test this hypothesis it gains some support by the observation that cwc are flourishing in the general area of the bari canyon and adjacent bottoms flushed by dense shelf water dsw cascading while they are much less developed on the basin s opposite side unaffected by this phenomenon

u th dating records of cold water coral colonization in submarine canyons and adjacent sectors of the southern adriatic sea since the last glacial maximum abstract the deep southern adriatic sea is home of widespread cold water coral colonization madrepora oculata lophelia pertusa desmophyllum dianthus which is at present limited by large to its western apulian margin and central part including the bari canyon system on the contrary the eastern side is today almost deprived of significant coral growth and this asymmetrical distribution has been ascribed primarily to the action of the north adriatic dense water naddw that impinges more efficiently on the apulian margin the collection of subfossil specimens of m oculata l pertusa and d dianthus provided the very first dates for cold water coral colonization along the eastern margin once combined with known distribution of live cold water corals and fossil occurrences in the southern adriatic sea uranium series dating provides evidence of i coral presence in the southeastern adriatic during the last glacial maximum lgm followed by ii a time of basin wide colonization after the post last glacial maximum and encompassing the younger dryas iii another time of undocumented coral presence with the onset of sapropel s1 perturbations of the thermohaline circulation in this sector of the mediterranean basin might have governed the presence and demise of the resident cold water coral populations interfering with strength and trajectories of main water masses it is hypothesized that the achievement of the current asymmetrical distribution did occur since the end of s1 protracting to present time the post s1 reorganization likely brought to the current hydrological situation where the influence of naddw prevails in the western side and corals are doing at best on its trajectory the scarcity of datable material makes the proposed scenario open to debate and in need of further supporting evidence

the sardinian cold water coral province in the context of the mediterranean coral ecosystems abstract a new cold water coral cwc province has been identified in the mediterranean sea in the capo spartivento canyon system offshore the southern coast of sardinia the sardinia cold water coral province is characterized in the nora canyon by a spectacular coral growth dominated by the branching scleractinian madrepora oculata at a depth of 380 460 m the general biohermal frame is strengthened by the common occurrence of the solitary scleractinian desmophyllum dianthus and the occasional presence of lophelia pertusa as documented by remotely operated vehicle survey this area is a hotspot of megafaunal diversity hosting among other also live specimens of the deep oyster neopycnodonte zibrowii the new coral province is located between the central mediterranean cwc provinces bari canyon santa maria di leuca south malta and the western and northern ones melilla catalan provencal ligurian canyons as for all the best developed cwc situations in the present mediterranean sea the new sardinian province is clearly influenced by levantine intermediate water which appears to be a main driver for cwc distribution and viability in this basin

megafauna distribution along active submarine canyons of the central mediterranean relationships with environmental variables abstract the tectonically controlled margins off southern italy are carved by several shelf indenting submarine canyons that are periodically flushed by sedimentary gravity flows in this study the distribution of benthic and demersal megafauna within the thalweg of some of these canyons i e the gioia petrace and caulonia marina canyons in the tyrrhenian and the ionian calabrian margins respectively and the sant agata san gregorio tremestieri and messina canyons in the messina strait was studied using remotely operated vehicle video transects the relationships between fauna distribution and environmental conditions i e seafloor type depth slope aspect and canyon system extracted from video footage and bathymetric data were assessed to identify the main physical drivers influencing the megafaunal assemblages within active submarine canyons these latter have their heads in shallow water so representing highly dynamic environments affected by present day sediment transport hierarchical cluster analysis allowed to distinguish seven different assemblages occurring in the study areas permanova analysis showed significant differences among species groups associated to different seafloor types depth ranges and canyon systems distance based linear modeling distlm identified the canyon system as the main factor explaining the variability of the megafaunal assemblages across the study areas in the gioia and petrace canyons both characterized by homogenous fine grained sediment the assemblages were mainly dominated by polychaeta sabellidae and ceriantharia the almost total absence of sessile fauna at the canyons head was interpreted as an effect of a strong physical disturbance due to the impact of sedimentary flows in the canyons of the messina strait the presence of more varied seafloor encompassing fine and coarse sediment along with an higher spatial heterogeneity of physical disturbance determined more diversified faunal assemblages featuring species associated with hard and soft substrates more in detail in the sant agata san gregorio and messina canyons the colonization of cobbles and boulders by slow growing species vulnerable to physical disturbance such as the gorgonians acanthogorgia hirsuta and swiftia dubia was recorded for the tremestieri canyons a stronger impact by sedimentary flows was reflected both by a very high abundance of land based litter and the lowest values of species richness interactions between megafauna and marine litter whose widespread occurrence was recorded on the floor of all these canyons have been also presented and discussed although in several cases litter caused entanglement of benthic species the anthropogenic debris was also used as growing substrate or shelter by some invertebrates and fishes suggesting complex fauna litter interactions that should be better explored overall the large variability in morphology and seafloor characteristics across the studied canyons is reflected on the variability of megafauna assemblages suggesting a strong influence of the physical conditions specific of each canyon in controlling fauna distribution

geology and paleoecology of early holocene lacustrine deposits in the columbia river valley near fauquier southern british columbia early holocene lake sediments are exposed near fauquier on the east side of the arrow lakes in the columbia river valley of british columbia a glacial lake occupied the valley at the time of deglaciation but by 10 ka bp this had been replaced by a nonglacial lake that was at least 250 km long and as much as 5 km wide comparison of pollen and macroscopic plant remains in these nearshore and littoral deposits with modern vegetation indicates that many of the plants present between 9 and 10 ka bp are found in the area today either along the valley floor or at higher elevations in the subalpine zone nearby some of the organic material may be allochthonous this complicates paleoecological and paleoclimatological interpretations it appears that the climate in the columbia river valley between 9 and 10 ka bp was as wet or wetter than at present the presence of many of these species in the southern columbia river valley of british columbia during early holocene time suggests that elements of the modern ve

physico chemical parameters of neoarchean syntectonic magmatism the example of the muscocho pluton abitibi subprovince abstract the muscocho pluton is one of a number of syntectonic neoarchean granodiorite intrusions formed during the main deformation phase in the abitibi subprovince that lead to stabilization of the superior craton such magma locally are associated with magmatic hydrothermal styles of mineralization interpreted by some works to reflect intrusion related gold systems irgs determining whether magmas can transport enough au to fertilize the upper crust during this tectonomagmatic interval requires insights into physico chemical parameters such as pressure temperature and oxygen fugacity o2 the o2 parameter is particularly important because it affects s speciation and s solubility which correlates with au solubility in magmas retrieving such parameters from the metamorphosed locally hydrothermally altered and generally deformed neoarchean rocks is particularly challenging as such this contribution uses fresh to altered granodiorites of the muscocho pluton a 16 km diameter granodiorite intrusion spatially associated with polymetallic mineralization to evaluate whether physico chemical parameters can be retrieved from ancient altered rocks based on amphibole apatite and zircon chemistry this study also has implications for the origins of the muscocho pluton which ascended slowly toward the upper crust as a single pulse of evolved magma and became emplaced at about 12 km depth the magma had an o2 above the ni nio solid oxygen buffer nno 1 which is not considered optimal for au transportation the magma also formed a deep intrusion unable to provide magmatic fluids to trigger an efficient hydrothermal system this study provides the basis for a systematic evaluation of the physico chemical conditions within which syntectonic magmas evolved in the upper crust knowledge of these physico chemical conditions are necessary to better constrain the irgs metallogenic model

reconstruction of the late pleistocene grassland of the columbia basin washington usa based on phytolith records in loess abstract silica phytoliths preserved in three loess sections in southeastern washington state revealed a 100 000 year history of the columbia basin grassland changes in the proportion of different morphotypes indicate large shifts in vegetation composition during the last 100 ka a low elevation section 677 m asl near the center of the basin provided a record of alternating xeric festuca poa and mesic festuca koeleria grassland the middle slope section 1095 m asl supported picea abies or pinus ponderosa forest or non analog parkland at different times some trees were present at or near the site even during the last glacial maximum the highest site 1220 m asl supported stipa festuca and poa dominated grassland with some artemisia shrub during most of the late pleistocene but supports a coniferous forest today variations in vegetation can be explained as a response to changes in large scale climatic controls grasslands and shrub steppe were apparently more widespread and forests more restricted than today during the marine isotope stages 2 and 4 probably as a result of cooler and drier conditions the three new records are well correlated with previously published paleo reconstructions based on phytolith cicada burrow and stable isotope data from a nearby kp 1 loess section carp lake pollen record and global ice volume variations

fish otoliths in superficial sediments of the mediterranean sea abstract otoliths represent a significant biogenic carbonate component in marine sediments that may provide valuable information for paleoenvironmental and biogeographic reconstructions in spite of their importance relatively little is still known about the taxonomic composition abundance and early taphonomic characteristics of recent otolith death assemblages which would add to their value to interpret situations in the geological record here we present data on the distribution of fish otoliths from bottom sediments collected in the central mediterranean sea ranging in depth from 51 to 3300 m the preservation of otoliths ranges from fresh semi translucent white specimens to dull coloured dark ones although whitish specimens are predominant across all the samples this diversity in lustre and colour and at times texture reflects the degree of early taphonomic processes undergone by these aragonitic bodies post mortem under submarine conditions never being exposed to diagenetic processes on land in general a correlation with depth is observed with best preservation observed in otoliths sampled at depths

evidence from thermoluminescence dating for middle wisconsinan deglaciation in the hudson bay lowland of manitoba we report here the first direct dating of the nonglacial intertill nelson river sediments from five sites in northern manitoba we used the thermoluminescence tl sediment dating technique to obtain age estimates of 32 46 ka for four samples and 119 ka for the fifth all samples previously correlated to the sangamonian stage 80 130 ka missinaibi formation we interpret the younger tl dates as being within 20 40 of the true deposition ages but interpret the oldest tl date as an overestimate because of ineffective zeroing of the light sensitive tl associated with observed pebble and sand detritus in that sample thus these younger direct dates imply a significant climatic warming and deglaciation in the heart of the laurentide ice sheet area during middle wisconsinan time

water flux estimates in the central mediterranean sea from an inverse box model 1 seasonal hydrological surveys and long term current measurements carried out during a wide investigation of the central mediterranean connecting the eastern and western parts of the basin with the tyrrhenian sea are used to estimate the absolute geostrophic flow through the region applying an inverse methodology the inverse box model prescribes conservation of water properties mass heat and salt inside closed boxes of water as well as the imposition of mean fluxes by direct current measurements the model result is a mean circulation of the region during four different periods along with simultaneous evaluation of water fluxes through the three boundary sections and the associated uncertainties the overall situation besides confirming previous qualitative knowledge on the mean circulation at all levels provides a novel quantitative pattern of the water mass exchange in a region that is crucial for the assessment of a more realistic budget for the whole basin the positive results obtained indicate that the inverse method may be considered an effective powerful tool for successful applications at regional scale

late quaternary vegetation near battle ground lake southern puget trough washington pollen and plant macrofossil records from battle ground lake along with published data are used to reconstruct the late quaternary vegetation history of the nonglaciated southern puget trough coinciding with the end of the evans creek stade circa 20 000 17 000 yr b p of fraser glaciation gramineae artemisia herbs and picea cf engelmannii grew in a parkland tundra around battle ground this assemblage recorded throughout the southern puget trough implies cold relatively dry conditions similar to subalpine environments east of the cascade range the presence of pseudotsuga picea sitchensis and alnus rubra as macrofossils suggests a slight interstadial warming between 17 000 and 15 000 yr b p cool humid conditions prevailed during the vashon stade when south of the cordilleran ice sheet open forest or parkland featured mesophytic subalpine taxa at battle ground lake temperate conifers were part of forest communities circa 11 200 yr b p but elsewhere they were present as early as 12 500 yr b p from 10 000 to 4500 yr b p pseudotsuga quercus savannah spread into the battle ground area offering evidence for summer drought more severe than today pseudotsuga and thuja forest was established in the late holocene with the introduction of the modern humid climate consideration of all the pollen data from the southern puget trough and the available radiometric chronology suggests that postglacial migration of most lowland conifers into the puget trough was rapid and not necessarily from southern refugia

targeted lagrangian sampling of submesoscale dispersion at a coastal frontal zone 1 the potential impact of rapidly evolving submesoscale motions on relative dispersion is at the forefront of physical oceanography posing challenges for both observations and modeling a persistent coastal front driven by river outflows in the north western mediterranean sea is targeted by two observational cruises conducted in the summer of 2010 the frontal zone is sampled using drifters launched with a multi scale strategy consisting of modules of triplets released on either side of the front by small boats this experiment is original in that the submesoscale range of 100 m to 1000 m is directly targeted and the results are expected to provide guidance for practical applications such as prediction of the initial spreading of pollutants and biogeochemical tracers the influence of submesoscale motions on relative dispersion is quantified using both particle mean square separation as a function of time and scale dependent finite size lyapunov exponents fsle our main finding is the identification of a local dispersion regime with values reaching as high as 20 days 1 at drifter pair separation distances of 100 m this value is more than an order of magnitude greater than that obtained by drifters in the offshore ligurian current the ligurian sea circulation is modeled using a fully realistic regional ocean modeling system roms with 1 60 horizontal resolution it is found that the numerical model significantly underestimates the relative dispersion at submesoscales indicating the need for particle dispersion parameterizations for unresolved processes

the west melilla cold water coral mounds eastern alboran sea morphological characterization and environmental context a new mound field the west melilla mounds interpreted as being cold water coral mounds has been recently unveiled along the upper slope of the mediterranean moroccan continental margin a few kilometers west of the cape tres forcas this study is based on the integration of high resolution geophysical data swath bathymetry parametric sub bottom profiler ctd casts acoustic doppler current profiler adcp rov video and seafloor sampling acquired during the topomed gassis 2011 and melcor 2012 cruises up to 103 mounds organized in two main clusters have been recognized in a depth range of 299 590 m displaying a high density of 5 mounds km2 mounds 1 48 m high above the surrounding seafloor and on average 260 m wide are actually buried by a 1 12 m thick fine grained sediment blanket seismic data suggest that the west melilla mounds grew throughout the early pleistocene holocene settling on erosive unconformities and mass movement deposits during the last glacial interglacial transition the west melilla mounds may have suffered a drastic change of the local sedimentary regime during the late holocene and unable to stand increasing depositional rates were progressively buried at the present day temperature and salinity values on the west melilla mounds suggest a plausible oceanographic setting suitable for live cwcs nonetheless more data is required to groundtruth the west melilla mounds and better constrain the interplay of sedimentary and oceanographic factors during the evolution of the west melilla mounds

benthic habitat characterization and distribution from two representative sites of the deep water sml coral province mediterranean abstract two sites ms04 and ms06 from the santa maria di leuca sml coral province were analyzed by a video and acoustic survey during the national italian project apulian plateau bank ecosystem study aplabes site ms04 atlantis mound is characterized by a sub conical mound 500 m wide and 25 m high located at a water depth of about 650 m site ms06 yellow chain comprises several elongated reliefs nnw sse oriented up to 25 m high and 500 m in maximum lateral extent located at a depth of between 490 and 540 m at both sites two main mesohabitats mound and intermound containing several coral bearing and barren macrohabitats were observed in recorded videos and detected in side scan sonographs the coral rich macrohabitats characterized by densely packed colonies of the scleractinians madrepora oculata and secondarily lophelia pertusa m l are typically restricted to the mound areas the mud dominated ones almost devoid of m l colonies are more common within the intermound mesohabitat however on the most extensive mounds both macrohabitat typologies exist they are heterogeneously distributed on the mound surface often showing a clear differentiation along two opposite flanks of the same topographic feature m l rich macrohabitats are preferentially located on top and along the mound northeastern flank showing a typical step like distribution probably reflecting the arrangement of hard substrate outcrops along this flank fan shaped madrepora colonies and sponges are often oriented nnw sse implying together with other evidence a primary southwestern current flow the hard bottom macrohabitats of the southwestern mound flank are generally restricted to sparse exposed subvertical to overhanging scarps as well as to heterometric boulders located at the scarp base their fauna is mainly characterized by small sized organisms such as sponges and solitary scleractinians although m sized boulders may locally host very large antipatharian colonies leiopathes glaberrima the heterogeneous distribution of the observed benthic macrohabitats seems to be strictly related to the local topography the main current flow and consequently larvae food supply per unit of time and the substrate typology hard vs soft bottom

proliferation and demise of deep sea corals in the mediterranean during the younger dryas abstract uranium series and radiocarbon ages are reported for deep sea corals madrepora oculata desmophyllum dianthus lophelia pertusa and caryophyllia smithii from the mediterranean sea u series dating indicates that deep sea corals have persisted in the mediterranean for over 480 000 years especially during cool interstadial periods the most prolific period of growth however appears to have occurred within the younger dryas yd period from 12 900 to 11 700 years bp followed by a short 330 years phase of post yd coral growth from 11 230 to 10 900 years bp this indicates that deep sea corals were prolific in the mediterranean not only during the return to the more glacial like conditions of the yd but also following the rapid deglaciation and transition to warmer conditions that followed the end of the yd surprisingly there is a paucity last glacial maximum lgm coral ages implying they were largely absent during this period when cold water conditions were more prevalent radiocarbon ages show that the intermediate depth waters of the mediterranean generally had 14 c compositions similar to surface waters indicating that these waters were extremely well ventilated the only exception is a narrow period in the yd 12 500 100 years bp when several samples of lophelia pertusa from the ionian sea had 14 c values falling significantly below the marine curve using a refined approach isolation ages isol of 300 years to 500 years are estimated for these intermediate 800 1000 m depth waters relative to surface marine waters indicating a reduction or absence of deep water formation in the ionian and adjacent adriatic seas during the yd contrary to previous findings we find no evidence for widespread intrusion of low 14 c atlantic waters into the mediterranean prolific growth of deep sea corals in the mediterranean ended abruptly at 10 900 years bp with many of the coral bearing mounds on the continental slopes being draped in a thin veneer of mud their demise is attributed to a number of factors including the direct loss of habitat due to high sedimentation that accompanied glacial meltwater pulses together with rising temperatures that would have finally pervaded the deeper water of the mediterranean following the onset of holocene warming

megabenthic assemblages in the continental shelf edge and upper slope of the menorca channel western mediterranean sea abstract highly diverse megabenthic assemblages dominated by passive and active suspension feeders have been recently reported in shelf edge environments of the mediterranean sea due to their frequent association with species of commercial interest these assemblages have been heavily impacted by fishing the vulnerability and low resilience of these assemblages composed mainly by long living and slow growing species have motivated the implementation of management measures such as the restriction of bottom trawling and the establishment of large protected areas embracing these environments the menorca channel is one of such areas recently included in the european union natura 2000 network quantitative analysis of video transects recorded at 95 360 m depth by manned submersible and remotely operated vehicles were used to characterize megabenthic assemblages and to assess their geographical and bathymetric distribution six different assemblages were identified mainly segregated by substrate type and depth hard substrates hosted coral gardens and sponge grounds whereas soft sediments were mainly characterized by large extensions of the crinoid leptometra phalangium and the brachiopod gryphus vitreus the good preservation of most of the observed assemblages is probably related to a low bottom trawling pressure which mainly concentrates deeper on the adjacent continental slope because of their biological and ecological value management and conservation measures need to be established to preserve these benthic assemblages

stratigraphic framework of the apulian deep water coral province ionian sea abstract shallow sediment lithology and stratigraphy were investigated at selected areas off santa maria di leuca sml on the apulian margin between 350 and 1200 m water depth in order to define the sea bottom character on which coral mounds have developed according to existing geophysical data and in situ observations deep coral growth in the sml area creates patches of colonies typically settled on hard substrates on the upper flanks and or near the top of mound like structures and elongated ridges the sedimentary stratigraphy is strongly influenced by the local topography which is modeled by tectonic and geomorphological forcing large scale erosional features slope failure and sediment mass accumulation are evident from seismic investigations additionally sites of preferential sediment accumulation due to the action of bottom currents are identified as a result a complex sedimentary pattern characterizes this part of the apulian margin with strong lateral variability in sediment type and age although hemipelagic silty clay constitutes the main lithology there are sites characterized by periodic accumulation of silt and fine sand and local re deposition of coarse biogenic sand from the surrounding areas and from shallower depths excluding one site where mid pleistocene sediments are brought very close to the bottom surface due to wide scale erosion all collected sediments are late pleistocene to holocene in age and fall biostratigraphically within the emiliania huxleyi acme nannofossil zone reworking detected through nannofossil analysis is common in most cores excluding the ones taken from topographic highs and is variable in extent from site to site and within the sediment column it includes cretaceous to early pleistocene species suggesting provenance from extended successions or various stratigraphic levels outcropping on the submerged apulian margin or in adjacent land sections reworking is often associated with a high content of lithogenic particles and an increase in the coarser silt fraction coral debris was collected at many stations both at the sediment surface and within the stratigraphic sequence with varying abundance in relation to proximity to the coral colonies radiometric dating and micropaleontological analyses at some sites allow us to propose a sequence of coral colonization phases

variability of the large scale general circulation of the mediterranean sea from observations and modelling a review abstract in this paper we present an overview of the most recent findings about the mediterranean sea present day circulation structure both historical observations and numerical model simulations are presented outlining the differences and agreement the model simulations are presented for both an eddy resolving and a coarse resolution numerical model and the results are intercompared the importance of the mesoscales in modifying the large scale flow field is elucidated the critical point is the discovery of the large amplitude interannual variability of the circulation and water mass structure associated with the anomalies of atmospheric forcing over the basin the seasonal variability can be strictly related to changes in heat and momentum fluxes while the interannual variability has a component which is related to the mesoscale field the latter is very intense in the algerian current region and levantine basin but different in structure in the two regions results are shown which confirm the importance of wind driving in establishing the kinetic energy of the flow field by comparing the current transport at the strait of corsica with observations in conclusion the essential characteristics of the present day circulation are associated with the atmospheric forcing and the basin topographic structure results from palaeoceanographic simulations for the last 20 000 years show that changing the atmospheric forcing can cause large changes in the circulation structure which may have affected sapropel formation

late quaternary paleoenvironments of the morley flats and kananaskis valley of southwestern alberta a 3 1 m section of limnic sediment and peat from a bog on the morley flats and a 2 8 m section of limnic sediment from wedge lake in the kananaskis valley have yielded the first comprehensive late quaternary biostratigraphic record from south western alberta both sections were analyzed for subfossil pollen molluscs and several sedimentary indices two distinct pollen zones were recognised the basal zone characterized by high relative abundancy of artemisia salix juniperus suggests that the morley flats were dominated by a sparse vegetation composed of aggressive pioneer species following deglaciation until prior to approximately 10 000 bp similarly the mollusc fauna from this zone is dominated by northern ranging species the second zone is typified by a predominance of pinus and picea this reflects the expansion of coniferous forest into the region both the relative abundance of southern ranging mollusc species and the total carbonate concentration in the sediment increase in this zone the veg

the impact of cascading currents on the bari canyon system sw adriatic margin central mediterranean abstract the bari canyon system bcs is a peculiar erosional depositional feature characterised by two main almost parallel conduits emanating from a broad crescent shaped upper slope region when viewed in cross sections parallel to the margin bcs appears markedly asymmetric with a right hand southern side that is higher and steeper about 800 m in relief and more than 30 steep the left hand side of the canyon is instead much smoother as a consequence bottom currents flowing along the slope from the north enter the canyon and interact with its complex topography leading to preferential deposition on the up current side of pre existing morphological relief where mass failure deposits generate morphologic relief outside the canyon sediment is preferentially deposited up current n ward bcs includes three main ew oriented sediment conduits canyon c to the south channel b in the central area and moat a in the north channel b shows a well developed levee deposit on its right hand side and appears markedly straight and erosional on the upper slope the deepest portion of channel b is substantially abandoned and draped but still shows a subdued thickening of the draped unit north and up current of pre existing morphologic relief confirming the impact of along slope flowing currents canyon c is flanked by erosional walls all the way to the basin floor where deep sea furrows develop with a nw se orientation today dense water formation in the adriatic is seasonally modulated and displays a significant variability on inter decadal scales dense water formation during glacial intervals was likely different from the modern because most of the north adriatic shelf was subaerially exposed and the deep water mixing in the south was likely reduced as suggested by paleoceanographic reconstructions the growth patterns of bcs since the lgm are characterised by concurrent erosion of the upper portion of channel b and of the lower portion of canyon c it is possible that flows through the straight narrow and steep upper segment of channel b spill over its right hand levee in ca 600 m water depth where the relief of levee b on the channel floor is minimal and enter canyon c where substantial erosion takes place in this view the upper portion of canyon c where hard grounds and corals are encountered is flushed by currents characterised by reduced turbidity while the lower part of canyon c collects additional flows from upper channel b

spatiotemporal bioerosion patterns in deep water scleractinians from off santa maria di leuca apulia ionian sea abstract this study focuses on the carbonate biodegradation processes of deep water scleractinians from off apulia at santa maria di leuca sml in the ionian sea including living colonies of lophelia pertusa madrepora oculata and desmophyllum dianthus the corallites were grouped into three zones the live zone edge zone and dead zone in total 13 trace types were encountered and are attributed to borings of sponges 3 fungi 6 foraminifers 2 bacteria 1 and annelids 1 their relative spatial appearance within the host skeletons led to the distinction between six succession stages of bioerosion the first endobiontic traces are exclusively produced by bacteria and fungi and are already present in the edge zone which could be attributed to their fast growth rates and or temporal exposure of the bare skeleton to the water column in d dianthus the entire ichnospecies assemblage has been documented within the first 1 9 cm below the live zone and represents the most condensed bioerosion succession amongst the coral species studied the strongest degradation of corallites at sml is made by boring sponges which can excavate 70 or more of the skeleton the finding of a unilateral condensed succession of bioerosion stages may be linked to prevailing unidirectional strong currents a comparison of the present ichnocoenosis with bioerosion studies from the eastern atlantic evidences a reduced ichnodiversity in ionian sea bathyal corals

growth and demise of cold water coral ecosystems on mud volcanoes in the west alboran sea the messages from the planktonic and benthic foraminifera the dhaka and maya mud volcanoes mvs located in the mud diapir province in the western alboran basin along the moroccan coasts were cored during the ttr 17 leg 1 cruise cores were taken on the top of the volcanoes at a water depth of 370 m on the dhaka mv core ttr17 ms411g and at 410 m water depth on the maya mv core ttr17 ms419g respectively on both mud volcanoes the extruded mud breccia provides the nucleation point for the colonization and development of cold water corals and associated ecosystems two phases of cold water coral growth are observed 1 between slightly older than 4175 62 years bp and around 2230 59 years bp at dhaka and 2 between slightly older than 15583 185 years bp and around 7613 38 years bp at maya mv on the top of the maya mv only a small patch reef and or isolated corals proliferated whereas a more extended patch reef colonized the top of the dhaka mv at both sites the cold water coral developmentwas triggered by the availability of a suitable substrate for initial coral settling provided either as a firm ground or as single clasts subsequently coral growth was supported by enhanced nutrient flux possibly related to upwelling and or strong currents during the intervals of coral growth planktonic foraminiferal assemblages were dominated by neogloboquadrina incompta the decline of coral ecosystems on the mud volcanoes is accompanied at surface by a shift fromthe n incompta dominated assemblage to a globorotalia inflata dominated assemblage possibly reflecting more oligotrophic conditions this shift is coeval to the passage from wet to arid conditions at the end of the african humid period at mayamv it is interpreted as an effect of an early human impact on a fragile environment which was already stressed by desiccation at the time of the development of complex human society along the mediterranean coasts at dhaka mv

olympia interstadial vegetation landscape history and paleoclimatic implications of a mid wisconsinan mis3 nonglacial sequence from southwest british columbia canada lithostratigraphic 14c and palynologic analyses of peat and silty peat at three nearby sites reveal a 25 000 year vegetation and climate history of the olympia interstade for the fraser lowland british columbia 300 km within the southern limit of the cordilleran ice sheet at lynn valley polypodiaceae fern spores and nonarboreal pollen dominate 47 8 14c ka bp reflecting unstable and cold landscapes a pinus poaceae zone follows representing pine parkland and cool dry climate fluctuating values of picea and tsuga mertensiana pollen at lynn and seymour valleys and port moody characterize most of the olympia interstade during local peat deposition in cyperaceae and myrica wetlands until about 26 7 14c ka bp under a cool and moist climate a brief pinus tsuga heterophylla zone at lynn valley 44 39 14c ka bp suggests a climatic optimum a poaceae artemisia assemblage and deposition of silty sand after 26 7 14c ka bp reflect cooling and drying after which a unique lycopodium assemblage at lynn valley

water mass characteristics and sill dynamics in a subpolar cold water coral reef setting at stjernsund northern norway the stjernsund located in subpolar setting at 70 5 n off northern norway hosts a thriving cold water coral reef community on a morainic sill dives with manned submersible jago identified the different reef zones and sedimentary facies on top and on the slopes of the sill hydrographic investigations indicate different water mass distribution east and west of the sill winter mode water and norwegian coastal water variability depends on the runoff and freshwater discharge into the fjord atlantic water dynamics are almost entirely tidally driven high resolution ctd time series covering a full tidal cycle demonstrate mixing processes occurring east of the sill additionally the different bathymetric distribution of living corals on the western and eastern slope of the sill portrays the dependence on these tidal dynamics the living corals thrive just below the isopycnal of 27 5 kg m 3 which marks the boundary between norwegian coastal water and atlantic water

megafauna of vulnerable marine ecosystems in french mediterranean submarine canyons spatial distribution and anthropogenic impacts abstract vulnerable marine ecosystems vme in the deep mediterranean sea have been identified by the general fisheries commission for the mediterranean as consisting of communities of scleractinia lophelia pertusa and madrepora oculata pennatulacea funiculina quadrangularis and alcyonacea isidella elongata this paper deals with video data recorded in the heads of french mediterranean canyons quantitative observations were extracted from 101 video films recorded during the medseacan cruise in 2009 aamp comex qualitative information was extracted from four other cruises two marum comex cruises in 2009 and 2011 and two ifremer cruises in 1995 and 2010 to support the previous observations in the cassidaigne and lacaze duthiers canyons all the species fishing impacts and litter recognized in the video films recorded from 180 to 700 m depth were mapped using gis the abundances and distributions of benthic fishing resources marketable fishes aristeidae octopodidae vulnerable marine species trawling scars and litter of 17 canyons were calculated and compared as was the open slope between the stoechades and toulon canyons funiculina quadrangularis was rarely observed being confined for the most part to the marti canyon and i elongata was abundant in three canyons bourcart marti petit rhone these two cnidarians were encountered in relatively low abundances and it may be that they have been swept away by repeated trawling the lacaze duthiers and cassidaigne canyons comprised the highest densities and largest colony sizes of scleractinian cold water corals whose distribution was mapped in detail these colonies were often seen to be entangled in fishing lines the alcyonacean callogorgia verticillata was observed to be highly abundant in the bourcart canyon and less abundant in several other canyons this alcyonacean was also severely affected by bottom fishing gears and is proposed as a vulnerable marine species our studies on anthropogenic impacts show that seafloor disturbance by benthic fishing is mainly attributable to trawling in the gulf of lion and to long lines where rocky substrates are present the bauxite residue red mud expelled in the cassidaigne canyon was seen to prevent fauna from settling at the bottom of the canyon and it covered much of the flanks litter was present in all of the canyons and especially in considerable quantities in the ligurian sea where the heads of the canyons are closer to the coast three marine protected areas and one fishing area with restricted access have recently been established and should permit the preservation of these deep ecosystems

dating the death of mediterranean deep sea scleractinian corals abstract several c 14 datings of deep sea scleractinians indicate that the major decline of this coral population in the mediterranean sea took place around 30 000 15 000 yrs b p it is probable that the most important factor causing such an event was the rise of temperature that either directly affected the physiology of the corals or more likely triggered unfavorable hydrological conditions

coral li mg thermometry caveats and constraints abstract the coral li mg temperature proxy is revisited through an in depth trace element analysis of scleractinians collected live from tropical to polar environments the dataset consists of li ca mg ca sr ca and li mg ratios from 64 coral specimens belonging to 8 different taxa including both reef building zooxanthellate and cold water non zooxanthellate species from a wide range of water temperature 1 to 29 5 c salinity 34 71 to 38 61 and depth 3 to 670 m our results showed that the reliability of the li mg temperature proxy is strongly limited by the organic matter associated with the coral skeleton which is most evident within the green bands observed in tropical corals organic rich bands can double the mg content otherwise present in the skeleton which may ultimately lead to a temperature overestimation exceeding 15 c we found that this bias can be overcome by the treatment of coral skeletons with a specific oxidizing cleaning protocol we also detected the presence of calcite deposits within the aragonite skeleton of some antarctic living coral specimens which strongly affects the robustness of the li mg proxy given its temperature sensitivity of 1 5 c 1 calcite therefore to obtain reliable reconstructions a correction needs to be applied when organic matter and or calcite contamination is present which requires the scrupulous assessment of the integrity of the aragonite prior to geochemical analyses given that some species entrap more organic matter than others and that some are more prone to calcite contamination a taxon related effect is apparent here we show that the tropical species porites spp pseudodiploria strigosa and orbicella annularis and the cold water species madrepora oculata caryophyllia antarctica and flabellum impensum are all suitable candidates for reconstructing seawater temperatures the integrated results across a wide temperature range from extreme cold to tropical shallow waters yield an overall precision for the li mg temperature proxy of 1 0 c as quantified by the standard error of estimates if calculated from the 95 prediction intervals the uncertainty of the temperature estimates is 0 9 c at 1 c 1 5 c at 12 c and 2 6 c at 25 c however the uncertainty for the tropical corals e g porites can be reduced to 0 6 c if a li mg and sr ca multi regression approach is applied

stratigraphy and paleoecology of pleistocene interstadial sediments central british columbia abstract two exposures of organic rich interstadial sediments in central british columbia provide information on middle wisconsinan environments and climates near the center of the region subsequently covered by the late wisconsinan cordilleran ice sheet interstadial sediments at bullion pit overlie drift of early wisconsinan or older age and underlie thick drift of late wisconsinan age alluvium or colluvium and peat were deposited on the floor of the ancestral quesnel river valley 46 000 40 000 14 c yr ago when the vegetation consisted of spruce forest with dry openings and local fens and the climate was colder and perhaps drier than today this is broadly consistent with paleoclimatic reconstructions for the same time interval for babine lake 400 km to the northwest and for meadow creek 400 km to the southeast plant rich pond sediments containing tephra layers and vertebrate remains are exposed between two drifts in a ravine at mexican hill 30 km east of quesnel although they may be contemporaneous with the bullion pit beds the nonglacial sediments at mexican hill more likely were deposited sometime after the warmest part of the last interglaciation but prior to 50 000 yr b p at that time the vegetation at mexican hill probably was parkland the present vegetation at mexican hill is boreal forest thus a drier and possibly cooler climate is indicated

formation of gold deposits a metamorphic devolatilization model a metamorphic devolatilization model can explain the enrichment segregation timing distribution and character of many goldfields such as those found in archean greenstone belts slate belts and other gold only provinces in this genetic model hydrated and carbonated greenschist facies rocks particularly metabasic rocks are devolatilized primarily across the greenschist amphibolite facies boundary in an orogenic setting devolatilization operates on the scale of individual mineral grains extracting not just h2o and co2 but also s and in turn au elevated gold in solution is achieved by complexing with reduced s and by h2co3 weak acid buffering near the optimal fluid ph for gold solubility the buffering is more important than being at the point of maximum gold solubility low salinity ensures low base metal concentrations in the auriferous metamorphic fluid migration of this fluid upwards is via shear zones and or into hydraulic fracture zones in rocks of low tensile strength the geometry of the shear zones dictates the kilometre scale fluid migration paths and the degree of fluid focusing into small enough volumes to form economic accumulations of gold deposition of gold from solution necessitates breakdown of the gold thiosulphide complex and is especially facilitated by fluid reduction in contact with reduced carbon bearing host rocks and or by sulphidation of wallrocks to generate iron bearing sulphide and precipitated gold as such black slate carbon seams banded iron formation tholeiitic basalt magnetite bearing diorite and differentiated tholeiitic dolerite sills are some of the important hosts to major goldfields gold deposition is accompanied by carbonation sulphidation and muscovite biotite alteration where the host rock is of suitable bulk composition the correlation of major gold deposits with rock type even when the gold is primarily in veins argues for rock dominated depositional systems not fluid dominated ones as a consequence a general role in gold deposition for fluid mixing temperature decrease and or fluid pressure decrease and boiling is unlikely although such effects may be involved locally several geological features that are recorded at gold only deposits today reflect subsequent modifications superimposed upon the products of this generic metamorphic devolatilization process overprinting by higher grade metamorphism and deformation and or palaeo weathering may provide many of the most obvious features of goldfields including their mineralogy geochemistry geometry small scale timing features geophysical response and even mesoscopic gold distribution

middle wisconsinan sediments and paleoecology of central british columbia sites at necoslie and nautley rivers at two sites in central british columbia sediments with dispersed organic matter underneath fraser glaciation deposits are interpreted as nonglacial deposits of middle wisconsinan age olympia nonglacial interval at necoslie river undated sand with dispersed organic matter thought to be fluvial in origin is overlain by fraser drift at nautley river similar sand contains plant detritus that has yielded 14c ages of 38 230 410 bp beta 88557 and 42460 670 bp beta 88558 pollen assemblages of the sediments with dispersed organic matter at the necoslie river and nautley river sites are similar both assemblages are dominated by herb pollen with a lesser amount of tree pollen the pollen assemblages are thought to reflect a tundra type vegetation because vegetation in the area is presently dominated by spruce and subalpine fir forest climate during deposition probably was much cooler than today data presented here support the contention of other studies in western canada that cooler climati

cold water coral growth in the alboran sea related to high productivity during the late pleistocene and holocene abstract cold water corals are common along the moroccan continental margin off melilla in the alboran sea western mediterranean sea where they colonise and largely cover mound and ridge structures radiocarbon ages of the reef forming coral species lophelia pertusa and madrepora oculata sampled from those structures reveal that they were prolific in this area during the last glacial interglacial transition with pronounced growth periods covering the bolling allerod interstadial 13 5 12 8 ka bp and the early holocene 11 3 9 8 ka bp their proliferation during these periods is expressed in vertical accumulation rates for an individual coral ridge of 266 419 cm ka 1 that consists of coral fragments embedded in a hemipelagic sediment matrix following a period of coral absence as noted in the records cold water corals re colonised the area during the mid holocene 5 4 ka bp and underwater photographs indicate that corals currently thrive there it appears that periods of sustained cold water coral growth in the melilla coral province were closely linked to phases of high marine productivity the increased productivity was related to the deglacial formation of the most recent organic rich layer in the western mediterranean sea and to the development of modern circulation patterns in the alboran sea