surface and subsurface data integration and geological modelling from the little ice age to the present in the ravenna coastal plain northwest adriatic sea emilia romagna italy abstract new geological analysis of the ravenna coastal plain has allowed a major update of the geological coastal model with anthropogenic overprints removed from an area heavily affected by human actions in the last four centuries a period in which the little ice age lia has had a large influence on the coastal dynamics the geological build up of the coastal plain is a natural occurrence that is important for understanding the present day coastal buildup however coastal zone anthropization has defined the actual coastal morphology canceling out most of surface expression needed to create an accurate coastal evolution model as the beach ridges morphology in the study area as the lack of surface expression due to the anthropogenic actions has changed the coastal zone under study it is not possible to only use geomorphological analysis to construct a local coastal evolution model because of this building a new model and understanding how coastal evolution would proceed without human influence would allow us to understand the interaction between natural forces and anthropogenic influence which has acted to shape the actual morphology of the study area from the lia period to the present days we therefore propose an integration of data using the following actual data from the surface such as the high resolution digital surface model dsm and the digital terrain model dtm the actual database from the emilia romagna region geological survey including the shapefile with the regional soil chart and the geological elements present in the study area knowledge from previous work carried out in the area and the subsurface data from ground penetrating radar gpr which would make the study the first to use a gpr survey of the coastal plain of the northwest adriatic in addition the work will follows a successful case study done in the southern brazilian coastal plain that integrated previous works done in the coastal plain with new methods such as gpr data acquisition the gpr data allows for corroboration of the interpretation of the coastal model constructed using the surface data finally the surface geological model proposed in this work may aid by providing the following i a new means for local coastal geology research ii a methodology to apply to other barrier lagoon systems around the world in order to update our knowledge about these systems and iii powerful information to support coastal managers and decision makers in constructing a long term master plan for effective integrated coastal zone management

styles of failure in late holocene highstand prodelta wedges on the adriatic shelf on the continental shelves of the northern mediterranean basin the late holocene highstand systems tract hst prograded un der the influence of major rivers after the attainment of the present sea level highstand about 5 5 cal kyr bp on the adriatic shelf the thickness distribution of the late holocene hst reflects the location of major deltas on the western side of the basin and the geostrophic cir culation which prevents a more uniform sediment dispersal toward the center of the basin very high sediment accumulation rates 1 to 10 cm year resulted in the construction of a hst depocenter up to 35 m thick this shore parallel depocenter is affected by failure of limited displacement over as much as 40 of its extent gas impregnation is common in the topset region and occurs at very shallow levels a few meters below the sea floor five areas are characterized by a variety of sea floor and subsurface crenulations although locally some of these crenulations have an intriguingly regular geometry sediment failure is the most plausible mechanism for their formation sediment failure better explains the large variety of geometries that characterizes the coastal mud prism of the late holocene hst furthermore we observe that these crenulations occur only where the downlap surface at the base of the hst is disrupted and affected by geometries that are con sistent with fluid escape processes this relationship suggests that the basal surface acts as a weak layer for sediment failure failure occurred in variable water depths from the northern slope of the modern po prodelta 10 20 m water depth to the narrow shelf offshore bari 40 110 m water depth in all these areas the proximal part of the hst prodelta wedge is intensely gas charged the thickness and age of the sediment sections affected by failure are slightly differ ent from place to place but appear everywhere younger than 5 5 cal kyr bp where failure affects the entire hst the detachment occurs on the downlap surface at its base failure geometries characterize the head region whereas compressional features such as pressure ridges and mud diapirs dominate in the toe region ranging in depth between 70 and 110 m where failure is limited to the upper few meters of the hst there is a clear lithologic change decrease in carbonate fraction and grain size across the basal surface this lithological change reflects a switch in sediment supply from local apennine rivers below to po derived mud this change occurred at the onset of the little ice age documenting the indirect control of short term climate change and hu man impact on sediment architecture the deformations affecting the late holocene hst in the various areas show differences in internal geometry but appear everywhere to be characterized by limited downward displacement and can be attri buted to shear dominated retrogressive failure it is suggested that some degree of consolidation occurred immediately after mobilization possibly induced by the escape of fluids nowhere has failure evolved into disintegration and flow likely because the type of cyclic loading that triggered it was not prolonged over a long enough interval short lived radionuclides in the uppermost stratigraphic layers which postdate the failure in the area offshore ortona allowed us to quantify systematic changes in sediment accumulation rates as a func tion of the underlying deformed sea floor in areas of wavy sea floor troughs show sediment accumulation rates of greater than 16 mm yr a figure that is fourfold the rate measured on the flanks of the troughs

stratigraphic units of the apulian tavoliere plain southern italy chronology correlation with marine isotope stages and implications regarding vertical movements abstract the geologic study of the apulian tavoliere plain apulia region southern italy is extremely difficult due to the scarcity of outcrops and fauna that could be used for dating the survey in progress of the 1 50 000 scale geological sheet no 409 zapponeta including the coastal zone of the apulian tavoliere has prompted us to tackle this problem by using a large set of borehole data and the aar dating method applied to ostracod shells which are capable of colonizing all types of environment as long as there is water this alternative approach has allowed us to recognise nine stratigraphic units or synthems and for the first time in this area to date them and to find a correlation between them and the cycles of sea level variation the recognised stratigraphic units are the coppa nevigata sands nea middle pleistocene mis 17 16 argille subappennine unit asp middle pleistocene mis 15 13 the coppa nevigata synthem nvi middle pleistocene mis 11 the amendola subsynthem mlm1 middle pleistocene mis 11 an undifferentiated continental unit uci middle pleistocene mis 8 7 the foggia synthem tgf middle late pleistocene mis 6 the carapelle and cervaro streams synthem rpl late pleistocene mis 5 3 and the inacquata farm synthem naq holocene within the rpl unit a buried cladocora caespitosa bioherm referable to mis 5 5 lacking in warm fauna and in which the coral is embedded in clay has been found in some boreholes this is the first finding of tyrrhenian deposits with c caespitosa along the italian adriatic coast the presence of this coral in clayey sediments a very uncommon occurrence strengthens the hypothesis that the major fossil reefs grew in coastal waters that were characterised by alluvial inputs of fine sediments higher turbidity and higher temperature than today in addition on the basis of the current evidence some consideration about the fauna of the mis 5 5 layer allows us to hypothesise that the adriatic sea underwent a more moderate warming compared to that of the ionian and tyrrhenian seas instead the finding in the nvi unit of a tropical lagoonal deposit with stromatolites referred to mis 11 proves that the warming in this stage was undoubtedly greater than that of mis 5 5 the mm4 borehole which goes through the mis 5 layers of the rpl unit made it possible to recognise two marine phases during mis 5 the first is referable to the mis 5 5 5 3 interval and the second to mis 5 1 mis 5 2 is marked by land emersion whereas no evidence of land emersion between mis 5 5 and 5 3 has been found also for the first time in this area uplifting and subsiding areas have been recognised and the vertical movements assessed in general the data suggest that the garganic apulian foreland and the amendola highland experienced an uplift while the central southern part of the study area belonging to the apulian tavoliere plain suffered a subsidence with rates increasing from north northwest to south southeast in particular the finding of the mis 5 5 buried layer with c caespitosa has allowed us to fill a gap in the data regarding the recent tectonic movements along the adriatic coast ferranti et al 2006 this feature proves that there has been a recent subsidence event since mis 5 5 in the coastal area of the apulian tavoliere plain

paleosols and associated channel belt sand bodies from a continuously subsiding late quaternary system po basin italy new insights into continental sequence stratigraphy previous sequence stratigraphic work has emphasized the key role of paleosols and associated sand dominated fluvial bodies as key features for interpreting alluvial architecture the temporal resolution of the ancient record is however insufficient to fully explain the complex relationship between soil formation and the evolution of fluvial systems under changing sea level and climate conditions in this paper we present a detailed record of paleosol channel belt relationships reconstructed from the subsurface of a rapidly subsiding region po plain italy that spans almost all of the last glacial interglacial cycle 120 k y the studied succession preserves a systematic bipartite zonation into a thick paleosol bearing segment close to the basin margin and a sand dominated interval with vertically amalgamated channel belts in an axial position individual paleosols are weakly developed and represent key stratigraphic markers that can be traced basinwide into adjacent essentially contemporaneous unconfined channel belt deposits unlike conventional models of late quaternary alluvial coastal plain systems no persistent incised valley was established in the po system during the last glacial interglacial cycle continuous accommodation was the key depositional control on alluvial stratigraphy during the prolonged 90 k y phase of late pleistocene sea level fall which led to the deposition of a thick dominantly aggradational alluvial succession the development of shallowly incised short lived valley systems took place only at the transition to glacial stages associated with substantial sea level drop marine oxygen isotope stage mis 3 2 transition and possibly mis 5 4 transition this study shows that in rapidly subsiding settings with high rates of sedimentation incised valley systems may be replaced by aggradationally stacked essentially nonincised fluvial bodies in these cases overbank packages bounded by immature paleosols represent the most likely alternative to the highly weathered interfluve paleosol predicted by classic sequence stratigraphic models fourth order sequence boundaries and lower rank erosional surfaces may be easily confused at the 100 k y scale and transgressive surfaces defining the onset of retrogradation may become the most readily identifiable sequence stratigraphic surfaces

new evidence on the evolution of the po delta coastal plain during the holocene abstract the po coastal plain dominated by the po and adige rivers deltaic systems is characterized by beach ridges which mark successive positions of the coastline during the holocene the most evident of these ridges are the most recent ones their dating is mainly based on archaeological and historical data the complex formed by some of the most prominent beach ridges was previously considered by experts to be the first post glacial shoreline this shoreline enclosed a single lagoonal system comprising the lagoon of venice and the delta of the main rivers more recent studies have instead allowed us to recognize other beach ridges older than this one these beach ridges are partially or totally buried by alluvial sediments belonging we believe to active subboreal shorelines additionally other studies we are now carrying out such as the geomorphologic map of the po plain and the venetian lagoonal system project have allowed the identification of older buried intertidal facies this work proposes a progradational model mainly developed by the building of the marine deltas including episodic or discontinuous lagoonal environments in opposition to the continuous lagoonal system model described up to now

early holocene coastal environment change inferred from deposits at okinoshima archeological site boso peninsula central japan abstract a series of deposits recording the early holocene drastic changes in coastal environment was investigated in terms of sedimentology and paleontology at the okinoshima archeological site on the southwest coast of boso peninsula central japan the deposits ca 3 m thick exposed in trenches consist of structureless mud and overlying stratified sand divided into three units i ii and iii in ascending order unit i is poorly sorted sandy mud with abundant opal phytoliths unit ii gradually overlying unit i is poorly sorted sandy mud containing more organic material and pieces of wood and archeological remains unit iii overlies unit ii with a sharp erosional contact and is composed of well sorted medium grained sand intercalated by mud layers with abundant plant fossils unit i suggests a dry surface on a coastal plain near uplands unit ii was transported from the upland onto the coastal plain by a debris flow unit iii deposits resulted from high energy river and storm surge flows onto the coastal plain the succession records that the sedimentary environments of the study site changed successively from a slope near the uplands to a fluvial plain to a coastal plain in response to a sea level rise in the early holocene ams ages of the units are approximately 10 000 cal bp and deposition occurred within 1000 years

compaction induced stress variations with depth in an active anticline northern apennines italy 1 it is shown that the stress field can vary with depth even within a homogeneous tectonic setting as documented for the active mirandola fault related fold along the buried front of the northern apennines analyses of borehole breakouts and other well data integrated with seismological information and field evidence show that extension perpendicular to the fold axis above approximately 1200 m changes to a strike slip stress field and finally to compression near the main detachment at depth similar along depth strain variations recognized in non active anticlines are usually explained by invoking tangential longitudinal strain folding i e stretching above and shortening below a neutral surface or gravitational instabilities however in this study we propose that differential compaction may play a significant and generally overlooked role with the aid of numerical modeling it is shown that where fold limbs are onlapped by highly compactable deposits as in the mirandola area differential compaction induces stretching at shallow 1 2 km depths the amount of stretching is a function of the shape of the fold and of the thickness of the syn tectonic sediments we conclude that in the mirandola case study the stress variations observed with depth are the result of a combination of a regional compression at depth and local tension driven by differential compaction of growth strata on the limbs of the anticline with respect to its crest

recent benthic foraminifera from the continental margin of northwest africa community structure and distribution abstract sediment grab samples were collected at 107 locations along the continental margin of northwest africa these samples form a series of depth transects between the straits of gibraltar and dakar senegal the greater than 250 m size fraction was retained for a census of both the live and dead foraminifera after deleting trace occurrences jaccard and correlation coefficient based cluster analyses were performed to decipher the community structure for this margin the geographic distribution of the four major faunal provinces recognized is conventional in that for both the live and dead assemblages three are related to depth upper slope and shelf middle slope and lower slope and continental rise the biotopes and thanatotopes within these provinces are strongly restricted along vertical or latitudinal boundaries when the data are analysed using jaccard coefficients dendrograms constructed from correlation coefficients emphasize depth related faunal communities dominant species such as cibicides lobatulus trifarina fornasinii planulina ariminensis uvigerina finisterrensis and c wuellerstorfi are generally distributed within a definite depth range along this margin and strongly influence the correlation coefficient based dendrograms other distributions are clearly not depth related but correspond to various environmental variables for example cancris auriculus coarse substrate bolivina subaenariensis oxygen minimum cibicidoides kullenbergi and hoeglundina elegans low organic carbon uvigerina peregrina is also a notable exception to depth dependence in that this dominant species and the province it represents are generally confined to the continental slope south of cape blanc its preference for that region may arise from the high organic carbon and fine grain size of the sediment there from low salinity of the bottom water or from other unknown variables the most important vertical faunal boundary occurs between cape barbas and cape blanc between 22 and 21 n latitude in contrast the canary island ridge intersects the continental margin at a saddle depth of about 1500 m but that physiographic barrier has little effect on provincialism of the deep water benthic foraminifera

shelf sequence and characteristic bounding surfaces in a wave dominated setting latest pleistocene holocene examples from northeast japan abstract this paper presents modern models for coastal to shelf sequences in a microtidal and wave dominated setting based on detailed analyses of latest pleistocene holocene sequences on the pacific side of northeast japan the latest pleistocene holocene sequences on the pacific side of northeast japan created in response to sea level changes for the last 30 kyr can be assigned to lowstand transgressive and highstand systems tracts related to sea level changes and show characteristic bounding surfaces and depositional systems these basically support the sequence architecture model of vail however transgression and regression occurred almost simultaneously with rise and fall of sea level in the study areas and so inflection points of sea level curves where the absolute slope or the rate of change is greatest are less significant for these high frequency sequences the characteristic bounding surfaces are a sequence boundary a transgressive surface which is the boundary between the lowstand and the transgressive systems tracts a ravinement surface which is found mainly in deposits of the transgressive systems tract and a maximum flooding surface which is the boundary between the transgressive and the highstand systems tracts the sequence boundary was created in response to falling sea level fluvial entrenchment shifted seaward with falling sea level therefore the boundary is a time transgressive unconformity and is not an isochronous boundary the transgressive surface is a nearby isochronous boundary that occurred when the shoreline had started to move landward from its maximum seaward excursion the ravinement surface is a diachronous surface created by shoreface erosion during transgression the shoreface erosion shifted landward with rising sea level and so the erosion surface created is time transgressive this surface is the most distinct bounding surface in the shelf sequence these characteristics of the bounding surfaces support and clarify the model of thorne and swift 1991 the transgressive systems tract on the shelf can be divided into two backstepping wedges separated by the ravinement surface the lower wedge consists of coastal plain and fluvial systems and the upper wedge is composed of transgressive sand and or sand ridges both the wedges show a backstepping depositional pattern which can be recognized in seismic records and cores these wedges correspond to the backstep backbarrier wedge and backstep shelf wedge of thorne and swift 1991 respectively

global sea level control on local parasequence architecture from the holocene record of the po plain italy abstract holocene deposits exhibit distinct predictable and chronologically constrained facies patterns that are quite useful as appropriate modern analogs for interpreting the ancient record in this study we examined the sedimentary response of the po plain coastal system to short term millennial scale relative fluctuations of sea level through high resolution sequence stratigraphic analysis of the holocene succession meters thick parasequences form the building blocks of stratigraphic architecture above the younger dryas paleosol a prominent stratigraphic marker that demarcates the transgressive surface early holocene parasequences s 1 3 record alternating periods of rapid flooding and gradual shoaling and are stacked in a retrogradational pattern that mostly reflects stepped post glacial eustatic rise conversely middle to late holocene parasequences s 4 8 record a complex pattern of coastal progradation and delta upbuilding that took place following sea level stabilization at highstand starting at about 7 cal ky bp the prominent transgressive surface at the base of parasequence 1 correlates with the period of rapid global sea level rise at the onset of the holocene mwp 1b whereas flooding surfaces associated with parasequences 2 and 3 apparently reflect minor early holocene eustatic jumps reported in the literature changes in shoreline trajectory parasequence architecture and lithofacies distribution during the following eustatic highstand had instead an overwhelming autogenic component mostly driven by river avulsions delta lobe switching local subsidence and sediment compaction we document a 1000 year delayed response of the coastal depositional system to marine incursion farther inland from the maximum landward position of the shoreline a dramatic reduction in sediment flux due to fluvial avulsion resulted in marine inundation in back barrier position whereas coastal progradation was simultaneously taking place basinwards we demonstrate that the landward equivalents of marine flooding surfaces parasequence boundaries may be defined by brackish and freshwater fossil assemblages and traced for tens of kilometers into the non marine realm this makes millennial scale parasequences whether auto or allogenic in origin much more powerful than systems tracts for mapping detailed extents and volumes of sediment bodies the holocene parasequences of the po coastal plain with strong age control and a detailed understanding of sea level variation may provide insight into the driving mechanisms and predictability of successions characterized by similar depositional styles but with poor age constraint resulting in more robust interpretations of the ancient record

sedimentary response to late quaternary sea level changes in the romagna coastal plain northern italy data from 17 continuously cored boreholes 40 170 m deep reveal the subsurface stratigraphy of the romagna coastal plain sedimentological and microfaunal data allow the distinction of eight facies associations of late pleistocene holocene age including 18 lithofacies and 16 faunal associations ten 14c dates provide the basis to establish a sequence stratigraphic framework for the succession corresponding to the upper part 35 ky bp of the last glacio eustatic cycle the eight facies associations can be grouped into lowstand transgressive and highstand systems tracts the upper part of the lowstand systems tract consists of alluvial plain deposits these accumulated during the late pleistocene when the shoreline was 250 km south of its present day position a pronounced stratigraphic hiatus between 25 and 8 8 ky bp is invariably recorded at the upper boundary transgressive surface of these pleistocene indurated and locally pedogenized alluvial deposits the succeeding postglacial history is represented by a well developed transgressive regressive cycle transgressive deposits interpreted to reflect the rapid landward migration of a barrier lagoon system include two wedge shaped paralic and marine units these thicken in opposite directions and are separated by a ravinement surface above the transgressive deposits the maximum flooding surface mfs marks the change from a transgressive barrier lagoon complex to a prograding wave dominated delta system early po delta the mfs can be traced landwards where it constitutes the base of lagoonal deposits an aggradational to progradational stacking pattern of upper delta plain marsh lower delta plain lagoon bay and delta front beach ridge deposits reflects the progressive increase in the sediment supply accommodation ratio during the following highstand the alluvial deposits capping the sequence accumulated by the 13th century ad in response to an avulsion event that caused abandonment of the former po delta lobe and the northward migration of the po river towards its present position

nonmarine sequence stratigraphy updip expression of sequence boundaries and systems tracts in a high resolution framework cenomanian dunvegan formation alberta foreland basin canada ten allomembers labeled j a have been mapped in the deltaic dunvegan formation using 2340 wells and 63 outcrop sections each allomember spans about 200 k y is bounded by regional transgressive surfaces and consists of 3 10 component shingles apparently of autogenic origin allomembers h e are discussed in this article their internal stacking patterns and bounding surfaces permit interpretation as depositional sequences sequences h f have a sigmoidal prismatic geometry downlap to the southeast and thin northwest onto the coastal plain no differential thickening exists toward the orogen in the southwest in contrast sequence e thickens markedly toward the northwest the tabular geometry of sequences h f suggests accommodation was controlled by sea level change whereas the wedge geometry of sequence e suggests significant tectonic tilting subaerial unconformities that bound valleys and extend onto adjacent interfluve paleosols can be traced 120 330 km updip into outcrop the base of each sequence is characterized by shoreline backstep of 80 150 km transgressive and highstand shingles in each sequence comprise marine deltaic deposits that pass landward into coastal plain strata falling stage shingles offlap seaward with little or no nonmarine equivalents updip whereas lowstand shingles show renewed coastal onlap in outcrop three nonmarine systems tracts are recognized 1 a channel dominated low accommodation systems tract fills valleys up to 35 m deep and is equivalent to the early transgressive systems tract begin page 1968 2 a lacustrine dominated high accommodation systems tract comprises mudstone enclosing ribbon channel sandstones blankets interfluves and forms the bulk of each sequence it is equivalent to late transgressive and early highstand systems tracts 3 a paleosol dominated low accommodation systems tract occupies the upper part of each sequence and is capped by the sequence boundary it is equivalent to the late highstand systems tract sequence bounding interfluve paleosols represent tens of thousands of years of pedogenesis related to slow aggradation followed by fluvial entrenchment and clastic bypass and represent the late highstand falling stage lowstand and early transgressive systems tracts coastal plain deposits record only part perhaps

reconstructing last glacial maximum and younger dryas paleolandscapes through subsurface paleosol stratigraphy an example from the po coastal plain italy abstract paleosols are commonly used to reconstruct ancient landscapes and past environmental conditions through identification and subsurface mapping of two pedogenically modified surfaces formed at the onset of the last glacial maximum lgm and during the younger dryas yd cold event respectively and based on their lateral correlation with coeval channel belt sand bodies we assessed the geomorphic processes affecting the po coastal plain during the late pleistocene 30 11 5 cal ky bp the 3d reconstruction of the lgm and yd paleosurfaces provides insight into the paleolandscapes that developed in the po alluvial plain at the transitions between warm and cold climate periods the lgm paleosol records a stratigraphic hiatus of approximately 5 kyr 29 24 cal ky bp whereas the development of the yd paleosol was associated with a climatic episode of significantly shorter duration both paleosols dissected by apennine rivers flowing from the south dip towards the north east where they are replaced by fluvial channel belts fed by the po river the lgm channel belt sand body reflects the protracted lateral migration of the po river at the onset of the glacial maximum it is wider 24 km and thicker 15 m of the fluvial sand body formed during the yd the northern margin of lgm po channel belt deposits was not encountered in the study area in contrast a spatially restricted paleosol identified in the north at the same elevation as the southern plateau may represent local expression of the alpine interfluve during the yd event this study highlights how 3d mapping of regionally extensive weakly developed paleosols can be used to assess the geomorphic response of an alluvial system to rapid climate change

sand composition and sedimentary evolution of a late quaternary depositional sequence northwestern adriatic coast italy abstract in order to detect temporal and spatial variations in detrital supply in the upper part of the last depositional sequence of late pleistocene holocene age we conducted a combined petrographic and stratigraphic study in the romagna coastal plain south of the po delta northern italy we analyzed heavy minerals and the bulk composition of sands from cores and surface samples by using petrographic and stratigraphic data on composition of modern beach and major river deposits new aspects of detrital dispersal mechanisms and the depositional history of the study area are documented the heavy mineral distribution coupled with the dolostone and volcanic rock fragment contents of bulk sands allow identification of three different petrofacies petrofacies a petrofacies b and petrofacies c which have been interpreted as of apenninic mixed eastern alps po river basin and po river catchment basin provenance respectively distribution of the three petrofacies changed through time in response to landward and seaward shifting of the coastline during the late pleistocene lowstand a pure apenninic provenance characterized the romagna coastal plain petrofacies a during the holocene transgression when the shoreline migrated tens of kilometers west of its present position eastern alpine sediment sources fed littoral facies petrofacies b probably as a result of southward transport by littoral drift this sediment supply continued during the early regressive phases and was cut off by a change in coastal morphology related to the development of the early po delta this led to the establishment of a sediment supply entirely related to the po river catchment basin petrofacies c changes in the compositional signature of sand in the youngest beach ridges mark the abandonment of the early po delta due to an avulsion event and testify to the establishment of a coastal system fed by rivers draining the apennines petrofacies a we emphasize sand petrography as an important tool in studying the internal architecture of sandy clastic depositional units on detailed spatial scales and its use in deciphering the depositional history of complex sedimentary successions fig 1 location of the study area end page 829

tectono sedimentary evolution and petroleum systems of the mundau subbasin a new deep water exploration frontier in equatorial brazil the brazilian equatorial margin bem evolved in response to transform motion between brazil and africa in 2012 petrobras drilled the pecem well in the mundau subbasin ceara basin of the bem to record the first deep water oil discovery in the region this work investigates the deep water evolution of the mundau subbasin focusing on its structural and sedimentary evolution and characterizes the petroleum systems in this new exploration frontier for such purposes poststack seismic reflection borehole and geochemical data were used three tectono stratigraphic sequences representing synrift mundau formation transitional paracuru formation and drift strata ubarana formation were divided into seven seismic units different tectonic domains were interpreted proximal distal and romanche fracture zone typical structures of transform margins such as marginal ridges and marginal plateaus were not identified in the mundau subbasin instead the subbasin was predominantly deformed by transtensional movements the mundau and paracuru formations are mature within the oil window whereas the ubarana formation is immature main reservoir intervals consist of approximately 1 m 3 28 ft thick intercalations of sandstone between shales siltstones and marls the seal rocks comprise shales in the ubarana formation whereas the hydrocarbon trap is related to an unconformity and a normal fault this work concludes that the paracuru formation is the main source and reservoir in the deep water mundau subbasin effectively comprising a paracuru paracuru petroleum system the results have significant implications for petroleum exploration in the bem by proposing a developed transitional petroleum system in the distal parts of northeastern brazil

eustatic and regional tectonic controls on late pleistocene paleovalley morphology in the central kanto plain japan abstract this study analyzed the morphology of three late pleistocene buried paleovalleys in the central kanto plain japan by using data from sedimentary cores and boreholes the paleo arakawa valley and the paleo nakagawa valley merge to form the paleo tokyo valley which extends into tokyo bay although the last glacial sea level fall controlled the formation of these paleovalleys fluvial terraces developed differently in these paleovalleys reflecting regional differences in tectonic activity the paleo tokyo valley beneath the tokyo lowland and the paleo arakawa valley beneath the arakawa lowland are in relatively stable or uplifting regions and both paleovalleys have several distinct fluvial terraces forming stepped cross sectional profiles in contrast in the paleo nakagawa and the paleo arakawa valleys beneath the subsiding menuma lowland terrace surfaces are obscure and there is a smooth gradient from the valley margins to the valley axis the structure of the paleovalleys in the central kanto plain can thus be explained by the combination of eustatic sea level fall and concurrent regional tectonic movement

barometric pressure influence on water table fluctuations in coastal aquifers of partially enclosed seas an example from the adriatic coast italy summary the water table level fluctuations in a coastal phreatic aquifer of the adriatic coast southern po plain italy were recorded to characterize groundwater level response to sea level fluctuations tide induced fluctuations atmospheric pressure loading and recharge from rainfall have all been recognized in the measured water table changes we also identified additional water table fluctuations that are not related to rain atmospheric pressure or tides we propose that these additional fluctuations are related to interaction of groundwater seiche events and inverted barometric effects their amplitude is important because at a distance of 70 m from the coast they have a magnitude of 0 07 m whereas the local tide has a 1 m amplitude seiches are standing waves that create sea water fluxes which affect groundwater below the first row of dunes in the study area we propose that this inverted barometric effect is an important process in creating water fluxes in the coastal zone that may strongly affect the position and width of the mixing zone between salt and fresh water

late quaternary palaeoenvironmental evolution of the adriatic coastal plain and the onset of po river delta abstract despite abundant geologic literature about the po coastal plain stratigraphic architecture beneath modern po river delta is virtually unknown in this paper combined sedimentological micropalaeontological and geochemical investigations of three continuous cores cores 1 to 3 about 40 m thick enable for the first time the detailed reconstruction of subsurface stratigraphy in the po river delta area along with its late quaternary palaeoenvironmental evolution lowstand deposits formed during the last glacial maximum are expressed as a fining upward succession of fluvial channel and related overbank deposits capped by a stiff overconsolidated horizon above this unconformable surface the lower post glacial succession transgressive systems tract or tst is less than 7 m thick and includes a deepening upward succession of back barrier shoreface and inner shelf deposits on the other hand the overlying highstand systems tract is considerably thicker up to 27 m and comprises the bulk of recent delta progradation i e vertically stacked prodelta delta front and delta plain deposits stratigraphic correlations within early transgressive back barrier deposits show vertically stacked thin shallowing upward successions reflecting an internal subdivision of tst into small scale parasequences the homogeneous shallow marine clay that accumulated at the turnaround from transgressive to highstand conditions can be palaeontologically differentiated into two packages miliolidae dominated and ammonia cribroelphidium dominated reflecting open marine and river influenced conditions respectively timing of maximum marine ingression maximum flooding surface mfs is recorded within the open marine clays at about 5500 calibrated yr bp by minor changes in microfauna geochemical characterization of core 1 testifies that distinct changes in sediment provenance accompanied the palaeoenvironmental evolution of the study area under changing relative sea level conditions at lowstand times the study area was an alluvial plain under the influence of adige river as suggested by comparatively high ba al values within pre holocene fluvial deposits increasing upward values of cr al 2 o 3 and ni mg within tst suggest an increasing sediment provenance from the po river during early stages of transgression via the longshore drift the onset of modern age po delta in the study area is precisely identified in core 1 at 25 10 m depth and has a distinctive double signature in terms of microfaunal assemblages po river sediments are clearly marked by the development of a characteristic foraminiferal association dominated by the opportunistic species nonionella turgida a taxon typically abundant in the marginal zone of present northern adriatic sea mud belt po river deposits are also fingerprinted by a peculiar geochemical composition corresponding to maximum cr and ni concentrations

maximum extent and dynamic behaviour of the last british irish ice sheet west of ireland a complete reconstruction of the last british irish ice sheet biis is hindered by uncertainty surrounding its offshore extent and dynamic behaviour this study addresses this problem by reconstructing the depositional history of four sediment cores taken from a series of sinuous glacigenic sediment ridges on the continental shelf west of ireland we present new geomorphic sedimentary and micropaleontological data that record a maximum westward biis extent that was at least 80 km farther offshore from any previous estimates the data suggests that a large ice shelf formed over parts of the shelf prior to retreat this new data increases the areal extent of grounded biis ice by 6700 km2 from previous estimates which represents a 3 increase in the irish sector of the ice sheet three new ams radiocarbon dates demonstrate for the first time that the biis advanced to the shelf edge during last glaciation late midlandian late devensian with ice advance onto the porcupine bank occurring after 24 720 260 yr cal bp deglaciation was complete by 19 182 155 yr cal bp thus constraining biis occupation over the porcupine bank to less than 5500 years estimated retreat rates of marine terminating ice across the shelf range from 70 to 180 myr 1

millennial scale depositional cycles from the holocene of the po plain italy the holocene depositional history of southeastern po plain on time scales of 103 yr is reconstructed based upon integrated sedimentological and micropalaeontological analyses of nine continuously cored boreholes about 40 m deep major palaeoenvironmental changes include the rapid landward migration of a barrier estuary lagoon system during the early middle holocene transgressive systems tract tst followed by extensive delta progradation in the last 6000 yr highstand systems tract hst detailed facies analysis of cores combined with the identification of 12 microfossils benthic foraminifer and ostracod associations allow an ultra high resolution sequence stratigraphic framework to be reconstructed particularly eight small scale high frequency cycles about 3 5 m thick and spanning intervals of time of about 1000 yr can be physically traced throughout the study area interpretation of these cycles which are invariably bounded by sharp flooding surfaces and generally show internal shallowing upward trends parasequences indicates that relative sea level changes during the holocene were episodic and punctuated by rapid phases of sea level rise followed by periods of stillstand or decreasing sea level rise from seaward to landward locations parasequence boundaries document beach barrier migration bay head delta abandonment and increasing accommodation in the coastal plain the ensuing phases of sea level stillstands resulted in the progressive filling of the newly formed accommodation space through beach progradation extensive mud deposition in behind barrier lagoonal estuarine and marsh deposits and aggradation in bay head delta systems at the head of estuaries eustacy appears to be the major controlling factor of the retrogradational stacking pattern of parasequences within the tst by contrast a complex interplay of eustacy sediment supply and subsidence with an increasing influence of autocyclic mechanisms such as channel avulsion and delta lobe abandonment controlled facies architecture within the hst the maximum flooding surface cannot be assumed to be synchronous its timing being strongly dependent upon local variations in sediment influx and subsidence this study shows that the micropalaeontologic characterization of mud prone coastal plain and estuarine successions in terms of water depth and salinity can lead to very accurate sequence stratigraphic interpretations allowing identification of parasequence boundaries that may not be detected by conventional stratigraphic approach

natural and anthropogenic factors affecting freshwater lenses in coastal dunes of the adriatic coast abstract this study characterizes the near shore portion of the shallow coastal aquifer included in the ravenna area northern italy with special attention to the roles of coastal dunes as freshwater reservoirs and their buffer on groundwater salinity the paper focuses on the presence and evolution of freshwater lenses below coastal dunes and highlights the existing differences between preserved natural dunes and dunes strongly affected by human intervention the influence that multiple natural and anthropogenic factors such as land cover local drainage network and beach erosion have on the presence size and evolution of the freshwater lenses in the aquifer is quantified and discussed the methodology includes multiple seasonal monitoring and sampling campaigns of physical water level salinity and temperature and chemical major cations and anions groundwater parameters results indicate that freshwater lenses where existing are limited in thickness about 1 2 m proximity to drainage ditches as well as limited dune elevation and size do not allow the formation and permanent storage of large freshwater lenses in the aquifer below the dunes the pine forest land cover that replaced the typical bush or sand cover intensifies evapotranspiration reducing net infiltration and freshwater storage the cation species distribution in the water shows that a freshening process is ongoing in preserved natural sites with stable or advancing beaches whereas a salinization process is ongoing in anthropogenic impacted areas with strongly fragmented dune systems currently the thin freshwater lenses in the shallow ravenna coastal aquifer are limited in space and have no relevance for irrigation or any other human activity the dune beach system however is the recharge zone of the coastal aquifer and its protection is important to reduce water and soil salinization which in turn control the health of the whole coastal ecosystem

onshore to offshore anatomy of a late quaternary source to sink system po plain adriatic sea italy abstract in understanding the evolution of siliciclastic systems late quaternary analogs may enable reliable predictive models of facies tract architecture the po plain adriatic sea system where a wealth of research has been conducted during the last 20 years represents one of the most intensively investigated late quaternary successions with the aid of a chronologically well constrained stratigraphy paleoenvironmental evolution is tracked for the first time from fluvial to deep marine realms over 1000 km in length vertical stacking trends onshore and stratal terminations offshore are the key observations that allow identification of surfaces with sequence stratigraphic significance systems tract boundaries in the distinct segments of the system recurring motifs in stratigraphic architecture showing tight coupling of sedimentary responses among source area catchment basin and coastal and marine depocenters reveal a cyclicity driven by glacio eustatic fluctuations in the milankovitch band due to high rates of subsidence middle pleistocene forced regressive systems tracts are exceptionally expanded and the mis5e mis2 interval late pleistocene preserves a nearly continuous record of fourth order 100 kyr stepwise sea level fall the stratigraphic architecture of last glacial maximum deposits highlights the genetic relations between channel belt development pedogenesis and sediment delivery to the lowstand delta through narrow incised valley conduits the late glacial holocene succession records the last episode of sea level rise and stabilization through well developed patterns of shoreline transgression regression tst hst that can be readily traced updip from offshore to onshore locations architectural styles across the whole system reflect a dominance of allogenic forcing in the tst as opposed to a predominantly autogenic control on stratigraphic development in the hst external drivers of facies architecture were also effective on millennial timescales the younger dryas cold reversal which marks the transgressive surface on land records a short lived episode of subaqueous progradation that is correlative onshore with widespread immature paleosol development and small sized channel belt formation quantitative assessment of sediment budgets over different time intervals requires precise positioning of the key bounding surfaces based on this approach we outline for the first time over the entire po adriatic basin an estimate of the sediment volumes stored in each systems tract

physical stratigraphy and sedimentology of the late pleistocene holocene tiber delta depositional sequence the tiber delta lies on the passive continental margin of central western italy the tiber delta is a late pleistocene holocene sedimentary succession and constitutes an incomplete high frequency depositional sequence 4th or 5th order which developed from the last post glacial rise in sea level to the present stillstand it is bound by a type 1 basal unconformity which cuts pleistocene deposits five depositional systems have been identified 1 coastal barrier lagoon 2 shelf transition 3 fluvial braided 4 tiber lagoonal deltas t1 t2 t3 and 5 tiber wave dominated delta the first four systems constitute the transgressive system tract tst which is characterized by a retrogradational parasequences set while the fifth system represents the highstand system tract hst characterized by only one parasequence progradational the evolution of these depositional systems has been mostly controlled by sea level rise which was not continuous but punctuated by eight minor stillstands and rapid rises this mechanism of sea level change led to the formation of parasequences that developed within the depositional systems from a palaeogeographical point of view the present tiber delta area was mainly characterized by a coastal barrier lagoon and tiber lagoonal deltas t1 t2 t3 which migrated landwards during the sea level rise throughout the time of the present stillstand the t3 lagoonal delta prograded rapidly into the lagoon reaching the coastal barrier and the lagoon was replaced first by marshes and then by the alluvial plain finally the tiber river overcame the littoral barrier supplying the coast giving rise to the present wave dominated delta

optically stimulated luminescence dating of a stratigraphic late glacial holocene sequence in the po plain bubano quarry bologna italy abstract quartz and k feldspars from an exposed 14 m thick undisturbed succession of silty clay late glacial holocene sediments in the po plain bubano quarry bologna province italy were optically dated for part of the sequence three radiocarbon ages and palynological dating provide an independent age control the separation procedures whose effectiveness was checked at each step by means of quantitative x ray powder analysis qxrpd and single aliquot regenerative dose protocols adopted are discussed in general the quartz optically stimulated luminescence osl ages are systematically younger than those obtained with feldspars probably due to the presence of medium component in the osl decay the evidence of contribution from the low sensitivity light traps has been checked using lm osl measurements and the equivalent doses have been calculated considering only the contribution of fast components moreover a residual presence of feldspars in the quartz separated fraction even if not detected by qxrpd could account for the observed underestimation the osl ages were consistent with the radiocarbon chronology

sequence stratigraphy seismic profiles and cores of pleistocene deposits on the rhone continental shelf abstract high resolution seismic profiles on the rhone deltaic shelf has shown the existence of a complex of pleistocene superimposed prograding wedges interrupted by a major incised valley system cutting across the shelf the individual wedges are interpreted from internal geometry and coring data as prograding shoreface deposits accumulated during periods of relative sea level lowering punctuated by small scale relative sea level falls or forced regressions they are related to 5th order glacio eustatic cycles and are stacked to form a composite 4th order sequence radiocarbon dating tandetron ams of the upper wedge to 40 ka bp indicates a stratigraphic hiatus across the shelf corresponding to the glacial maximum lowstand at the end of the wurmian cycle isotopic stage 2 during which sea level had dropped to 120 m below present sea level seaward tilting of the wedge boundaries indicate that the shelf has been subjected to differential subsidence that provides the necessary accommodation space for deposits to accumulate on the mid outer shelf the seaward tilting results from a cumulative effect of sediment and hydrostatic loading tectonism is also expressed by a westward shore parallel tilting in the area east of the incised valleys the amount of tilting the stacking pattern of the wedges and the location of incised valleys are structurally controlled by the alpine orogen which dips westward under the rhone margin the tectonic component interacts with glacio eustatic sea level fluctuations and accounts for the partition of the shelf into two areas with specific features separated by the rhone incised valleys

coastal aquifer response to extreme storm events in emilia romagna italy with global warming and sea level rise many coastal systems will experience increased levels of inundation and storm flooding especially along sandy lowland coastal areas such as the northern adriatic coast italy understanding how extreme events may directly affect groundwater hydrology in shallow unconfined coastal aquifers is important to assess coastal vulnerability and quantifying freshwater resources this study investigates shallow coastal aquifer response to storm events the transitory and permanent effects of storm waves is evaluated through the real time monitoring of groundwater and soil parameters in order to characterize both the saturated and unsaturated portions of the coastal aquifer of ravenna and ferrara southern po delta italy results highlight a general increase in hydraulic head and soil moisture along with a decrease in groundwater salinity and pore water salinity due to rainfall infiltration during the 2 days storm event the only exceptions are represented by the observation wells in proximity to the coastline within 100 m which recorded a temporary increase in soil and water salinity caused by the exceptional high waves which persist on top of the dune crest during the storm event this generates a saline plume that infiltrates through the vadose zone down to the saturated portion of the aquifer causing a temporary disappearance of the freshwater lens generally present although limited in size below the coastal dunes despite the high hydraulic conductivity the aquifer system does not quickly recover the pre storm equilibrium and the storm effects are evident in groundwater and soil parameters after 10 days past the storm overwash recess

sedimentary history of the western bohai coastal plain since the late pliocene implications on tectonic climatic and sea level changes abstract thick cenozoic deposits from the western bohai coastal plain a tectonic subsiding region provide the potential to study the relations between sedimentary environments and tectonic climatic and sea level changes however sedimentary history of this region extending to the whole quaternary as well as their links to tectonic climatic and sea level changes are still poorly understood mainly because of the lack of long term records with well constrained chronology in this study we present an integrated record based on sedimentology and proxies grain size and color reflectance of a 203 6 m core recovered from the western bohai coastal plain near tianjin the core was chronologically well constrained using paleomagnetic and optically stimulated luminescence dating methods the results show that from the late pliocene 3 3 ma to the late pleistocene 0 10 ma the study region was mainly dominated by fluvial setting and the extensive incursion of sea water into this region began during the last interglacial period 0 10 ma the sedimentology and the color index suggest that tectonic subsidence of the bohai basin during the plio quaternary must have played a significant role in controlling the sedimentary environments in this region the changes in base level because of sea level fluctuations during the quaternary influenced the fluvial development greatly and led to the alternations of coarse crevasse splay channel and finer floodplain deposits in the core sequence in addition climatic changes since the late pliocene also have had significant effects on the sedimentary settings in the bohai coastal plain by influencing the fluvial process with a series of mechanisms

late quaternary depositional architecture of po and tevere river deltas italy and worldwide comparison with coeval deltaic successions abstract po and tevere rivers form two of the most important deltas of the whole mediterranean area detailed investigations have been carried out in the last decade beneath the present delta plains of these two river systems using borehole data correlation with the aid of radiocarbon dates and other dating methods pollens archaeology a detailed sequence stratigraphic framework has been constructed in both areas especially for the last glacial interglacial cycle regional subsidence combined with short term sea level fluctuations of relatively high amplitude played a fundamental role in creating subtracting accommodation during the long phase of falling sea level which followed the tyrrhenian substage 5e transgressive event a discontinuous record of this phase is present in the subsurface of the po plain whereas poor or no preservation has been detected in the tevere area progradational lowstand wedges accumulated during the last glacial maximum mostly in the central part of the basins far from the present deltas and are lacking in the study areas where a hiatal surface is invariably recorded below the transgressive deposits glacioeustasy exerted a major control on sedimentation in both areas during the latest pleistocene holocene sea level rise infilling of fluvial valleys and rapid landward migration of barrier lagoon systems in the context of wave dominated estuaries characterized the transgressive phase in both po and tevere systems in place drowning and transgressive submergence mechanisms of barrier migration were effective predominantly between 13 5 and 9 ka bp in contrast shoreface retreat was dominant in the late transgressive phase the maximum flooding surface mfs can be traced physically from continental to marine deposits and has similar characteristics in the po and tevere river systems being marked by peat layers or lagoonal deposits at landward locations and by distinctive lithological characteristics and micro and macrofossils assemblages basinwards above the mfs the early highstand systems tract records initially the filling of the lagoons followed by the rapid progradation of wave dominate delta systems and flanking strandplains autocyclic processes such as distributary channel avulsion delta lobe abandonment and local subsidence due to sediment compaction were the fundamental controlling factors on sedimentation during deposition of the hst the stratigraphic architecture of the post glacial po and tevere delta complexes closely resembles the basic facies successions documented from coeval deposits of wave dominated and wave influenced clastic coasts both locally within the mediterranean area and in other parts of the world our study emphasizes however some additional features and major differences with previously published depositional models including i the development of backstepping wave dominated estuaries during transgression ii consistent changes through time in the mechanism of barrier migration iii a later construction of the delta systems with respect to what traditionally considered

sedimentology and chronology of the advance and retreat of the last british irish ice sheet on the continental shelf west of ireland the last british irish ice sheet biis had extensive marine terminating margins and was drained by multiple large ice streams and is thus a useful analogue for marine based areas of modern ice sheets however despite recent advances from investigating the offshore record of the biis the dynamic history of its marine margins which would have been sensitive to external forcing s remain inadequately understood this study is the first reconstruction of the retreat dynamics and chronology of the western marine terminating margin of the last late midlandian biis analyses of shelf geomorphology and core sedimentology and chronology enable a reconstruction of the late midlandian history of the biis west of ireland from initial advance to final retreat onshore five ams radiocarbon dates from marine cores constrain the timing of retreat and associated readvances during deglaciation the biis advanced without streaming or surging depositing a bed of highly consolidated subglacial traction till and reached to within 20 km of the shelf break by 24 000 cal bp ice margin retreat was likely preceded by thinning grounding zone retreat and ice shelf formation on the outer shelf by 22 000 cal bp this ice shelf persisted for 2500 years while retreating at a minimum rate of 24 m yr and buttressing a 150 km long 20 km wide bathymetrically controlled grounding zone a large 150 km long arcuate flat topped grounding zone wedge termed here the galway lobe grounding zone wedge glgzw was deposited below this ice shelf and records a significant stillstand in biis retreat geomorphic relationships indicate that the biis experienced continued thinning during its retreat across the shelf which led to increased topographic influence on its flow dynamics following ice shelf break up and grounding zone retreat past the glgzw at this stage of retreat the western biis was comprised of several discrete asynchronous lobes that underwent several readvances sedimentary evidence of dilatant till deposition suggests that the readvances may have been rapid and possibly associated with ice streaming or surging the largest lobe extended offshore from galway bay and deposited the galway lobe readvance moraine by 18 500 cal bp further to the north an ice lobe readvanced at least 50 km offshore from killary harbour possibly by 15 100 cal bp the existing chronology currently does not allow us to determine conclusively whether these readvances were a glaciodynamic internally driven response of the ice sheet during deglaciation or were climatically driven following the 18 500 cal bp readvance the galway lobe experienced accelerated eastward retreat at an estimated rate of 113 m yr

glacio eustatic control of continental shallow marine cyclicity from late quaternary deposits of the southeastern po plain northern italy abstract integrated sedimentological and micropaleontological foraminifera ostracods pollens investigations of a 173 m long continuous core in the subsurface of the se po plain reveal a cyclic facies distribution of continental to shallow marine deposits radiometric and pollen data enable an age attribution of the study units to the late middle pleistocene holocene glacioeustasy appears to have exerted a major control on facies development as documented by the close relationships between cyclic lithofacies patterns and the curves of eustatic fluctuation particularly relative sea level falls and lowstand phases were characterized by the development of alluvial sedimentation whereas major transgressive pulses and subsequent highstands are reflected by abrupt shifts to paralic and shallow marine deposits this facies architecture is paralleled by a distinctive pollen distribution reflecting the alternation of a glacial type of vegetation dominated by pinus and nonarboreal pollen types with interglacial mixed deciduous broad leaved forests

composition and evolution of the early oceans evidence from the tagish lake meteorite abstract laboratory leaching studies of the tagish lake meteorite demonstrate that the most readily leached cations of carbonaceous chondrite meteorites are mg ca na and k with the most readily leached anions being so4 cl and po4 in decreasing order of abundances soluble organics were not analyzed due to limited sample sizes magnesium and sulfate the most abundant solutes leached from tagish lake meteorite are also the most abundant ions of salts lining fractures of aqueously altered meteorites these same ions probably were the most abundant solutes of the first permanent oceans which probably formed during or soon after the late heavy bombardment stage 4 2 to 3 7 ga considering the residence time of cl in modern seawater and the composition of the exposed continental crust to at least 3 3 ga evolution of seawater from mg so4 dominated to nacl dominated would have required about 3 105 yr and could not have been complete until about 3 0 to 3 3 ga the calculations also suggest that the first permanent oceans were more saline than modern seawater and as argued by others these aspects have significant implications for evolution of life many solar system bodies besides earth probably derived a significant proportion of their volatile and soluble constituents from carbonaceous chondrite material therefore primordial solutions similar to those presented here were likely important in the early evolution of aqueous systems throughout the solar system including those present on carbonaceous chondrite parent asteroids and icy outer solar system satellites

geochemistry and stable isotope composition of surface waters from the ravenna plain italy implications for the management of water resources in agricultural lands this paper examines the issues related to salinization and water quality in the complex drainage system of the historical land reclamation of lamone basin ravenna coastal plain northern italy with the aim of guiding ongoing agricultural related decisions major and trace element concentration and o h b sr isotope ratios were measured on surface water from a network of canals and ditches sampling was carried out during the winter period and in summer to assess the effects of agricultural water management on the aquatic system results show widespread salinization of waters over the entire crop due to both the direct saltwater inland flushing through the canals in proximity of the mouths and sea salt leaching from soils during winter salinization is partly mitigated by rainfalls while in summer dilution processes are due to freshwater input from outside the watershed planned to assist the agricultural water demand in the winter season the concentration of some elements such as fe mn al and cu in waters exceeds the maximum permissible limits imposed by the italian regulations while during summer the concentration of these elements is significantly reduced a seasonal cycling is established where the bottom sediments of canals and ditches act as sinks of harmful elements mostly through adsorption by fe mn al oxy hydroxide solid phases the irrigation practice although improving the water quality increases water turbidity by re mobilization of sediments which act as transport agents of contaminants with detrimental effects that may become significant over the years

sand composition changes across key boundaries of siliciclastic and hybrid depositional sequences abstract sand composition of arenite successions is sensitive to a suite of factors operating between initial grain production and final diagenesis on a variety of spatial and temporal scales seven allogenic factors the relative importance of which relies upon the complex interaction between tectonics eustasy and climate play a decisive role in dictating petrofacies distribution within siliciclastic to hybrid depositional sequences these factors include i tectonic exhumation ii physical and chemical rock breakdown iii change in sediment flux iv change in source basin physiography v shelf colonization by organisms vi generation of chemical grains and vii volcanism autogenic processes may locally have a considerable influence on the type and amount of sediment supplied to the basin thus interfering with the external control based upon literature data a conceptual framework of expected compositional changes across the key surfaces for sequence stratigraphic interpretation is outlined two case histories from the miocene shelf to turbidite deposits of the northern apennines and the quaternary alluvial to nearshore succession of the adriatic coast respectively are used as references to illustrate how arenite petrofacies changes can be framed into a sequence stratigraphic scheme on multiple timescales

soluble ions dynamics in mediterranean coastal pinewood forest soils interested by saline groundwater abstract the aim of the study was to evaluate the dynamics of soluble ions in the soils of a pinewood forest of the mediterranean coastal area in the province of ravenna italy a one year monitoring was carried out in four entisols of the san vitale pinewood forest a vulnerable natural area due to subsidence and salt water intrusion ionic soluble forms were examined in saturated paste extracts spes and compared to groundwater soluble forms due to the local thermo pluviometric conditions both the water table depth and groundwater electrical conductivity ecw varied widely ranging respectively from 0 to 162 cm in depth and from 2 to 28 ds m 1 in salinity content as expected this greatly influenced soluble ions concentrations in soil horizons leading to variations in salt s speciation in soils with a deep water table typic ustipsamments superficial horizons showed a prevalence of ca 2 and hco 3 ion forms during the whole year while in the deep horizons na and cl were the dominant ions during summertime in soils with a shallow water table sodic psammaquents superficial ions enrichment was detected with na and cl ions being prevalent autumn and winter rainfall provoked the leaching of both na and especially of cl ions leaving hco 3 as the main anion in the soils with intermediate water table depth and moderate salinity aquic ustipsamments less relevant variations were observed during winter the ca 2 ion was the most present at the soil surface together with hco 3 during summer ca 2 and cl were the most present ions at the soil surface at deeper horizons na and cl ions always prevailed the sodium adsorption ratio sar reached the greatest values 40 during summertime in sodic psammaquents superficial horizons and in typic ustipsamments deep horizons on the basis of mixing curves na and cl displayed a conservative behavior and a likely sea origin both the ca 2 and so 4 2 ions appeared to be partially released from the solid soil fraction while the mg 2 ion seemed to be partially absorbed by the solid matrix on the basis of the hydrochemical characterization of both groundwater and soil spes it was possible to identify different refreshing and salinization processes along the soil profiles the one year monitoring of both the whole soil profile and groundwater never performed before allows a better understanding of the presence of distinct plant species and disease symptoms

influence of sediment provenance on background values of potentially toxic metals from near surface sediments of po coastal plain italy systematic variability in metal concentrations is recorded in near surface 1 m deep late quaternary sediments of po coastal plain across the boundary between alluvial deposits of apenninic provenance and a formerly active now abandoned delta lobe of the po river in the latter area high cr and ni concentrations exceeding the national standard limits are attributed to sediment provenance from ultramafic source rocks of po catchment basin and not to anthropogenic impact spatial distribution of carbonate related elements such as ca and sr displays consistent differences between the two areas confirming a primary control of provenance domains on sediment composition accurate facies characterization of near surface sediments coupled with detailed information on sediment dispersal patterns enable a reliable interpretation of the spatial variability of major elements and trace metals in the study area particularly detailed reconstructions of source area composition and changes in flow directions through historical times allow precise correlation of apparently anomalous geochemical patterns with distinctive depositional events such as shifts in channel course crevasse splay formation and beach ridge evolution the findings of unusually high natural provenance controlled heavy metal concentrations in pre industrial near surface levels highlight the contribution of a sedimentological approach to a reliable interpretation of geochemical data this should be taken into account when determining background values versus anthropogenic impact

systematic vertical and lateral changes in quality and time resolution of the macrofossil record insights from holocene transgressive deposits po coastal plain italy abstract in siliciclastic marine settings skeletal concentrations are a characteristic feature of transgressive intervals that provide insights into biological and sequence stratigraphic processes to investigate taphonomic signatures of transgressive intervals we analysed three cores along a depositional profile from the high resolution chrono and stratigraphic framework of the holocene po coastal plain in northern italy coupled multivariate taphonomic and bathymetric trends delineated spatial and temporal gradients in sediment starvation bypassing suggesting that quality and resolution of the fossil record vary predictably along the studied depositional profile moreover integration of taphonomic bathymetric and fossil density trends across the study area reveals distinctive signatures useful in characterizing facies associations and determining surfaces and intervals of sequence stratigraphic significance within the southern po plain succession taphonomic degradation of macroskeletal remains increases from proximal nearshore to distal offshore locations this trend is discernible for both biologically driven bioerosion and physically driven e g dissolution abrasion shell alterations compared to the up dip most proximal core the down dip core is distinguished by shell rich lithosomes affected by ecological condensation co occurrence of environmentally non overlapping taxa and by higher taphonomic alteration the onshore offshore taphonomic trend likely reflects variation in sediment accumulation along the depositional profile of the holocene northern adriatic shelf with surface near surface residence time of macroskeletal remains increasing down dip due to lower accumulation rates these results indicate that during transgressive phases changes in sea level base level are likely to produce down dip taphonomic gradients across shelves where the quality and resolution of the fossil record both deteriorate distally radiocarbon calibrated amino acid racemisation dates on individual bivalve specimens and the chronostratigraphic framework for this profile suggest jointly that the high levels of taphonomic degradation observed distally developed over millennial time scales 8ky whereas in proximal setting overall low taphonomic degradation and geochronologic constrains point to centennial scale time averaging during the late transgression phase patterns documented in the holocene transgressive and lowermost regressive deposits of the southern po plain may be characteristic of siliciclastic dominated depositional systems that experience high frequency base level fluctuations

age dating and the orbital theory of the ice ages development of a high resolution 0 to 300 000 year chronostratigraphy using the concept of orbital tuning a continuous high resolution deep sea chronostratigraphy has been developed spanning the last 300 000 yr the chronology is developed using a stacked oxygen isotope stratigraphy and four different orbital tuning approaches each of which is based upon a different assumption concerning the response of the orbital signal recorded in the data each approach yields a separate chronology the error measured by the standard deviation about the average of these four results which represents the best chronology has an average magnitude of only 2500 yr this small value indicates that the chronology produced is insensitive to the specific orbital tuning technique used excellent convergence between chronologies developed using each of five different paleoclimatological indicators from a single core is also obtained the resultant chronology is also insensitive to the specific indicator used the error associated with each tuning approach is estimated independently and propagated through to the average result the resulting error estimate is independent of that associated with the degree of convergence and has an average magnitude of 3500 yr in excellent agreement with the 2500 yr estimate transfer of the final chronology to the stacked record leads to an estimated error of 1500 yr thus the final chronology has an average error of 5000 yr