the sub himalayan fold thrust belt in the 1905 kangra earthquake zone a critical taper model perspective for seismic hazard analysis 1 we investigate the broader epicentral area of the m 7 8 1905 kangra earthquake s north india affecting the sub himalayan hills the tectonics of the area is characterized by two major rentrants kangra and dehradun interposed by the nahan salient the first order topography between the himalayan frontal thrust and the main boundary thrust shows a marked lateral variation along strike of the mean gradient characterized by a very small mean slope angle 1 in correspondence with the reentrants and higher values 3 in the salient these tectonic and topographic features also show a good correspondence with the peculiar macroseismic field of the 1905 event s which is characterized by two distinct intensity maxima separated by a distance of 150 km clearly overlapping the two major tectonic reentrants in this paper based on available geological and geophysical information and a critical analysis of the general mechanical constraints the seismogenic volume of the external sector of the chain is investigated in terms of critical taper model attempting to clarify the possible correlations between tectonics topography and seismicity in the sub himalayan belt based on different assumptions three possible seismotectonic scenarios are explored in order to constrain their likelihood and therefore to suggest a potential seismic gap in the area corresponding to the nahan salient which may experience an event of significant magnitude in the future

kinematics of the western africa eurasia plate boundary from focal mechanisms and gps data summary the western mediterranean displays a complex pattern of crustal deformation distributed along tectonically active belts developed in the framework of slow oblique plate convergence we used earthquake and global positioning system gps data to study the present day kinematics and tectonics of the africa eurasia plate boundary in this region crustal seismicity and focal mechanisms analysed in terms of seismic moment release and seismic deformation outline the geometry of major seismic belts and characterize their tectonics and kinematics continuous gps data have been analysed to determine euler vectors for the nubian and eurasian plates and to provide the global frame for a new mediterranean gps velocity field obtained by merging continuous and campaign observations collected in the 1991 2005 time span gps velocities and displacements predicted by the nubia eurasia rotation pole provide estimates of the deformation accommodated across the tectonically active belts the rather simple deformation occurring in the atlantic region characterized by extension about perpendicular to the middle atlantic and terceira ridges and right lateral motion along the gloria transform fault turns into a complex pattern of deformation occurring along broader seismic belts where continental lithosphere is involved our analysis reveals a more complex fragmentation of the plate boundary than previously proposed the roughly e w trending mainly compressive segments i e southwestern iberia northern algeria and southern tyrrhenian where plate convergence is largely accomodated across rather localized deformation zones and partially transferred northward to the adjacent domains i e the algero balearic and tyrrhenian basins are interrupted by regions of more distributed deformation i e the rif alboran betics tunisia libya and eastern sicily or limited seismicity i e the strait of sicily which are characterized by less homogeneous tectonics regimes mainly transcurrent to extensional in correspondence of the observed breaks tectonic structures with different orientation interfere and we find belts with only limited deformation i e the high and middle atlas the tunisian atlas and the offshore tunisia libya belt that extends from the plate boundary into the nubian plate along pre existing tectonic lineaments our analysis suggest that the sicilian pelagian domain is moving independently from nubia according to the presence of a right lateral and extensional decoupling zone corresponding to the tunisia libya and strait of sicily deformation zone despite the space variability of active tectonic regimes plate convergence still governs most of the seismotectonic and kinematic setting up to the central aeolian region in general local complexities derive from pre existing structural features inherited from the tectonic evolution of the mediterranean region on the contrary along calabria and the apennines the contribution of the subducted ionian oceanic lithosphere and the occurrence of microplates i e adria appear to substantially modify both tectonics and kinematics finally gps data across the gibraltar arc and the tyrrhenian calabria domain support the hypothesis that slab rollback in these regions is mostly slowed down or stopped

evidence for sea level oscillations by the characteristic thickness of marine deposits from raised terraces of southern calabria italy abstract clastic deposits associated with marine terraces can provide evidence for detecting eustatic oscillations the method is based on the characteristic thickness ct of beach formations which are generally deposited on a wave cut platform between the breakpoint and the swash upper limit on any present day coast ct reflects equilibrium related to current shore processes with a constant sea level it represents a local threshold t cr as when sea level rises ct increases by a value equal to the rise amplitude this amount is reduced in uplifted areas by the magnitude of coeval uplifting the amplitude of sea level variations detected by ct can be calculated knowing ct t cr uplift rate and the duration of an oscillation the method is applied to the clastic deposits of 23 marine terraces stepped between 52 and 172 m and shaped over the mis 5 mis 4 period along the calabria coast of the messina strait not only the great orbital oscillations mis 5 5 mis 5 3 mis 5 1 and mis 3 are recorded but also several rapid and low amplitude events are detected into each substage the most surprising result is the ten small oscillations during mis 5 5 the duration of which ranges between 2 ka and less than 1 ka while sea level oscillates from 0 5 to 12 m in amplitude by calculating initial relative sea level highstands and also lowstands preceding them detailed eustatic oscillations of the curve are drawn

formal ratification of the quaternary system period and the pleistocene series epoch with a base at 2 58 ma in june 2009 the executive committee of the international union of geological sciences iugs formally ratified a proposal by the international commission on stratigraphy to lower the base of the quaternary system period to the global stratotype section and point gssp of the gelasian stage age at monte san nicola sicily italy the gelasian until then had been the uppermost stage of the pliocene series epoch the base of the gelasian corresponds to marine isotope stage 103 and has an astronomically tuned age of 2 58 ma a proposal that the base of the pleistocene series epoch be lowered to coincide with that of the quaternary the gelasian gssp was also accepted by the iugs executive committee the gssp at vrica calabria italy which had hitherto defined the basal boundary of both the quaternary and the pleistocene remains available as the base of the calabrian stage age now the second stage of the revised pleistocene in ratifying these proposals the iugs has acknowledged the distinctive qualities of the quaternary by reaffirming it as a full system period correctly complied with the hierarchical requirements of the geological timescale by lowering the base of the pleistocene to that of the quaternary and fully respected the historical and widespread current usage of both the terms quaternary and pleistocene copyright 2009 john wiley sons ltd

overview of the montalbano jonico area and section a proposal for a boundary stratotype for the lower middle pleistocene southern italy foredeep abstract in the southernmost part of the southern apennine foredeep crops out a well exposed and continuous succession about 500 m thick of muds and muddy silts and several interbedded volcaniclastic layers on the basis of nannofossil biostratigraphy it ranges from large gephyrocapsa to pseudoemiliania lacunosa zones that indicate the upper part of the lower pleistocene and the lower part of the middle pleistocene the vertical distribution of both invertebrate fossil assemblages and teleostean otoliths points out changes in the primary environmental parameters particularly bathymetry sedimentation rate and oxygen concentration the observations allowed the reconstruction of several deepening shallowing cycles within a general regressive framework the montalbano jonico composite section is likely to represent a regressive portion of a third order cycle in which relevant tectonic pulses should be the main reason for the general shallowing possibly related to the beginning of the filling up phase of the southern part of the apennines foredeep the two recognized fourth order cycles could be related to tectonoeustatic causes the higher frequency cyclicity represented by several fifth order cycles seems to be mainly connected with astronomical relationships the montalbano jonico section could be suitable for defining the lower middle pleistocene boundary stratotype the potential gssp could be located close to the small gephyrocapsa p lacunosa zonal boundary near a biohorizon rich in delectopecten vitreus a muddy dark grey sapropelitic layer rich in chondrites ichsp and in oxygen isotopic stage 25 another potential location of the gssp of middle pleistocene could be near the volcaniclastic horizon v4 close to the isotopic stage 19 boundary

active stress map of italy we present a new map of the present day stress field in italy obtained from all the available data the map reports 200 horizontal stress directions inferred from 109 borehole breakout data 44 centroid moment tensor solutions 34 other focal mechanisms most of which are from polarity distributions seven stress inversions of microearthquake data two averages of t and p axes of earthquake focal mechanisms in zones of diffuse seismic activity and four fault slip data the integration of breakout data which yield horizontal stress directions with fault plane solutions which reflect the stress regime allows us to obtain an improved map of the present day stress in italy this stress field map can be used for a better comprehension of active tectonic processes for seismic hazard assessment and to foresee the behavior of faults recognized with other methods stress directions obtained from different data although relative to different depth intervals e g 0 7 km for breakouts and 0 20 km for most of the earthquakes and to different tectonic units are consistent since many regions in italy are characterized by an extensional stress regime we report the minimum horizontal stress shmin orientations the map shows that an extensional regime affects most of the apenninic belt conversely a compressional or transpressional regime characterizes the eastern alps the eastern side of the northern apennines and the southern tyrrhenian to northern sicily zone an abrupt change in stress directions marks the transition between northern and southern apennines suggesting that the two arcs are characterized by a different tectonic setting and recent evolution in this paper we report all the data analyzed to date with their geographic coordinates and average stress directions and we describe the main stress provinces in italy in the framework of the tectonic evolution of the region

using hydrogeochemistry to understand inter aquifer mixing in the on shore part of the gippsland basin southeast australia groundwater in the latrobe valley in the gippsland basin of southeast australia is important for domestic agricultural and industrial uses this sedimentary basin contains a number of aquifers that are used for water supply dewatered for open pit coal mining and which are potentially influenced by off shore oil and gas production major ion chemistry together with stable and sr isotope data imply that the main hydrogeochemical processes are evapotranspiration with minor silicate and carbonate weathering methanogenesis and so4 reduction in reduced groundwater associated with coal deposits have also occurred groundwater has estimated 14c ages of up to 36ka and is largely 3h free carbon 14 ages are irregularly distributed and poorly correlated with depth and distance from the basin margins the observations that the geochemistry of groundwater in aquifers with different mineralogies are similar and the distribution of 14c ages is irregular implies that the aquifers are hydraulically connected and horizontal as well as vertical inter aquifer mixing occurs the connection of shallow and deeper aquifers poses a risk for the groundwater resources in gippsland as contaminants can migrate across aquifers and dewatering of shallow units may impact deeper parts of the groundwater system

groundwater chemistry near an impoundment for produced water powder river basin wyoming usa summary the powder river basin is one of the largest producers of coal bed natural gas cbng in the united states an important environmental concern in the basin is the fate of the large amounts of groundwater extracted during cbng production most of this produced water is disposed of in unlined surface impoundments a 6 year study of groundwater flow and water chemistry at one impoundment skewed reservoir has produced the most detailed data set for any impoundment in the basin data were collected from a network of 21 observation wells and three suction lysimeters a groundwater mound formed atop bedrock within initially unsaturated unconsolidated deposits underlying the reservoir heterogeneity in physical and chemical properties of sediments resulted in complex groundwater flow paths and highly variable groundwater chemistry sulfate bicarbonate sodium and magnesium were the dominant ions in all areas but substantial variability existed in relative concentrations ph varied from less than 3 to more than 9 and total dissolved solids concentrations ranged from less than 5000 to greater than 100 000 mg l selenium was a useful tracer of reservoir water selenium concentrations exceeded 300 g l in samples obtained from 18 of the 24 sampling points groundwater travel time from the reservoir to a nearby alluvial aquifer a linear distance of 177 m was calculated at 474 days on the basis of selenium concentrations the produced water is not the primary source of solutes in the groundwater naturally occurring salts and minerals within the unsaturated zone dissolved and mobilized by infiltrating impoundment water account for most of the solute mass in groundwater gypsum dissolution cation exchange and pyrite oxidation appear to be important reactions the complex geochemistry and groundwater flow paths at the study site underscore the difficulty in assessing effects of surface impoundments on water resources within the powder river basin

delivery of marine chloride in precipitation and removal by rivers in the murray darling basin australia abstract rising groundwater tables and increasing river salinities are major problems in the semi arid murray darling m d drainage basin of se australia chemical data from precipitation rivers and groundwaters are integrated here to estimate chloride fluxes in the context of dramatic alteration of the hydrologic balance in the basin initiated during european settlement approximately 150 years ago our analysis indicates that about half of cl deposition from the atmosphere in the western murray basin is derived from resuspended regional continental dust resulting in high ca na ratios in bulk precipitation samples estimates of recent marine deposition of cl to the m d basin were made by excluding rainfall data from sites having high ca na ratios basin wide budgets for cl delivery from the atmosphere and removal by rivers indicate that the darling basin retains about 90 of current annual input of marine cl whereas the river murray exports two to three times current annual input to the murray basin exclusive of the darling some implications from this study are as follows 1 1 re evaluation of net marine cl input by rain implies that recent model calculations of 36 cl cl inputs from the atmosphere to the murray basin may differ significantly from actual values in particular net 36 cl cl input ratios from the atmosphere to the western murray basin may be a factor of two higher than those derived assuming all cl in rain is of recent marine origin 2 2 the very large inventories of salt within the two catchments especially the saline groundwaters of the murray basin accumulated over very long periods probably of the order of a few million years the current rearrangements of stored salinity as a result at least in part of human perturbations of the hydrologic balance are likely to continue for an extended period because of the massive quantities of salts involved and thus present major limitations on options for long term management of the m d basin

deformed pleistocene marine terraces along the ionian sea margin of southern italy unveiling blind fault related folds contribution to coastal uplift 1 morphotectonic analysis and fault numeric modeling of uplifted marine terraces along the ionian sea coast of the southern apennines allowed us to place quantitative constraints on middle pleistocene holocene deformation ten terrace orders uplifted to as much as 660 m were mapped along 80 km of the taranto gulf coastline the shorelines document both a regional and a local fault induced contribution to uplift the intermingling between the two deformation sources is attested by three 10 km scale undulations superimposed on a 100 km scale northeastward tilt the undulations spatially coincide with the trace of nw se striking transpressional faults that affected the coastal range during the early pleistocene to test whether fault activity continued to the present we modeled the differential uplift of marine terraces as progressive elastic displacement above blind oblique thrust ramps seated beneath the coast through an iterative and mathematically based procedure we defined the best geometric and kinematic fault parameters as well as the number and position of fault segments fault numerical models predict two fault propagation folds cored by blind thrusts with slip rates ranging from 0 5 to 0 7 mm yr and capable of generating an earthquake with a maximum moment magnitude of 5 9 6 3 notably we find that the locus of predominant activity has repeatedly shifted between the two fault systems during time and that slip rates on each fault have temporally changed it is not clear if the active deformation is seismogenic or dominated by aseismic creep however the modeled faults are embedded in an offshore transpressional belt that may have sourced historical earthquakes

deep structure of the southern apennines italy thin skinned or thick skinned 1 the deep structure of the southern apennines sa accretionary wedge is still debated since industrial seismic reflection and well data provide reliable constraints only to a depth of about 10 km as a consequence two directly linked questions regard 1 the shortening in the accretionary prism particularly within the buried apulian thrust units and 2 the degree of involvement of the lower plate basement i e the apulian crystalline basement to address these issues we have constructed a regional section along a recently released deep seismic reflection profile crop 04 which intersects the entire sa the resulting cross section adequately constrained to a depth of about 15 km has been framed in a geodynamic scenario characterized by the eastward roll back of the westward subducting apulo adriatic lithosphere on the basis of this section we speculate on the deep structure building both thin and thick skinned thrust models a cross check of these end members models against documented tectonic geophysical and geochemical features shows that the thin skinned model is generally more consistent with the available data the development of basement slices with thicknesses of tens of kilometers is unlikely while it remains possible that the apulian basement could have been involved with its upper few kilometers in the thin skinned model the total shortening of the allochthonous units i e apennine and apulian carbonate platforms and lagonegro basin is estimated to be greater than 280 300 km some 90 km of shortening can be attributed to the apulian thrust units

review secular tectonic evolution of archean continental crust interplay between horizontal and vertical processes in the formation of the pilbara craton australia the archean pilbara craton contains five geologically distinct terranes the east pilbara karratha sholl regal and kurrana terranes all of which are unconformably overlain by the 3 02 to 2 93 ga de grey superbasin the 3 53 3 17 ga east pilbara terrane ep represents the ancient nucleus of the craton that formed through three distinct mantle plume events at 3 53 3 43 3 35 3 29 and 3 27 3 24 ga each plume event resulted in eruption of thick dominantly basaltic volcanic successions on older crust to 3 72 ga and melting of crust to generate first tonalite trondhjemite granodiorite ttg and then progressively more evolved granitic magmas in each case plume magmatism was accompanied by uplift and crustal extension the combination of conductive heating from below thermal blanketing from above and internal heating of buried granitoids during these events led to episodes of partial convective overturn of upper and middle crust these mantle melting events caused severe depletion of the subcontinental lithospheric mantle making the ep a stable buoyant unsubductable continent by c 3 2 ga extension accompanying the latest event led to rifting of the protocontinent margins at between 3 2 and 3 17 ga after 3 2 ga horizontal tectonic forces dominated over vertical forces as revealed by the geology of the three terranes karratha sholl and regal of the west pilbara superterrane the c 3 12 ga whundo group of the sholl terrane is a fault bounded 10 km thick volcanic succession with geochemical characteristics of modern oceanic arcs including boninites and evidence for flux melting that indicate steep archean subduction at 3 07 ga the 3 12 ga sholl terrane 3 27 ga karratha terrane and c 3 2 ga regal terrane accreted together and onto the ep during the prinsep orogeny this was followed by development of the de grey superbasin an intracontinental sag basin and widespread plutonism 2 99 2 93 ga as a result of orogenic relaxation and slab break off craton wide compressional deformation at 2 95 2 93 ga culminated with 2 91 ga accretion of the 3 18 ga kurrana terrane with the ep this compression caused amplification of the dome and keel structure in the ep final cratonization was effected by emplacement of 2 89 2 83 ga post tectonic granites

quaternary normal faulting in southeastern sicily italy a seismic source for the 1693 large earthquake summary we present geological and morphological data combined with an analysis of seismic reflection lines across the ionian ovshore zone and information on historical earthquakes in order to yield new constraints on active faulting in southeastern sicily this region one of the most seismically active of the mediterranean is avected by wnw ese regional extension producing normal faulting of the southern edge of the siculo calabrian rift zone our data describe two systems of quaternary normal faults characterized by diverent ages and related to distinct tectonic processes the older nw se trending normal fault segments developed up to 400 kyr ago and striking perpendicular to the main front of the maghrebian thrust belt bound the small basins occurring along the eastern coast of the hyblean plateau the younger fault system is represented by prominent nnw sse trending normal fault segments and extends along the ionian ovshore zone following the ne sw trending avola and rosolini ispica normal faults these faults are characterized by vertical slip rates of 0 7 3 3 mm yr 1 and might be associated with the large seismic events of january 1693 we suggest that the main shock of the january 1693 earthquakes m 7 could be related to a 45 km long normal fault with a right lateral component of motion a long term net slip rate of about 3 7 mm yr 1 is calculated and a recurrence interval of about 550 50 yr is proposed for large events similar to that of january 1693

mass transport deposits and geo hazard assessment in the bradano foredeep southern apennines ionian sea abstract seafloor bathymetry combined with multi scale seismic reflection profiles were used to describe the morphostructural setting of the bradano foredeep gulf of taranto northern ionian sea where a submerged portion of the southern apennines is facing the apulia platform in the calabrian arc convergent margin in this complex area marine geophysical data highlight the presence of two mega slide deposits at the shelf slope transition which are most likely the largest ever described in the region these slid masses named the bradano basento megaslide bbms and bradano basento megaslide 1 bbms1 form a mass transport deposit complex mtdc affecting and eroding the topmost portion of the outer apennines deformation front and the apulian foreland ramp it was emplaced in late pleistocene times inside the narrow about 10 km wide bradano foredeep basin a plio pleistocene submarine trough developing at the chain front the youngest of these deposits bbms1 likely predates the last glacial maximum location of the mtdc within the subduction complex suggests that active tectonics and seismic shaking might represent the main triggering mechanisms for gravitative instability in this area although gravitational tectonics and sediment creeping mechanisms cannot be excluded on the other hand size and distribution of the mtdc in the sedimentary record of the bradano foredeep suggest the need of re evaluating the potential for large earthquakes tsunamis and more in general geological hazard related to submarine sliding masses along the coast of this highly populated area

vegetation changes during the late early pleistocene at montalbano jonico province of matera southern italy based on pollen analysis pollen analysis of the early pleistocene montalbano jonico section in southern italy reveals cyclic changes driven by climate and eustasy as illustrated by mesothermic vs steppe elements for climate and pinus vs caryophyllaceae amaranthaceae chenopodiaceae and ephedra for eustasy these results are directly compared with oxygen isotope data on globigerina bulloides constrained within a biostratigraphic framework based on nannofossils and foraminifers facilitating a new age calibration for the section marine isotopic stages 37 to 23 1 250 0 900 ma are recorded and compared with global and mediterranean oxygen isotope curves high frequency changes in pollen are related to the mediterranean curve globigerinoides ruber from odp site 967 and superimposed the lr04 stack curve during the early pleistocene pollen recorded global and regional climate changes related to obliquity and precession respectively and regional tectonic evolution precession forcing was caused by mediterranean wetness related to precession the intensified precession effect over climatic cycles that is expected during the middle pleistocene transition is not recorded in the montalbano jonico interval a vegetation changes

comment on the age of late pleistocene shorelines and tectonic activity of taranto area southern italy by g bellouomini m caldara c casini m cerasoli l manfra g mastrronuzzi g palmentola p sanso p tuccimei and p l vesica 6quaternary science reviews 21 525 5479 1

middle late pleistocene polycyclic evolution of a stable coastal area southern apulia italy abstract the otranto leuca coastal tract is marked by the presence of numerous sea caves placed close to present sea level they are located generally at the back of a shore platform covered by a sequence of breccia deposits marine sediments and speleothems at grotta di masseria dell orte marine cemented sands rest on a narrow shore platform at about 6 2 m above mean sea level and are covered by speleothems older than 185 ka at grotta del diavolo which is mostly filled by breccia deposits three beach levels have been detected at about 3 0 3 5 and 5 9 m above msl they are either covered by or overlie speleothems that yield an u th age of 340 78 ka and between 170 3 and 146 5 respectively geomorphological evidence and radiometric ages indicate that the area after a period of uplift has been tectonically stable since the last part of the middle pleistocene so that marine landforms close to the present shoreline underwent a polycyclic evolution the sedimentary fills of sea caves formed during middle late pleistocene glacial stages when arid or semiarid conditions promoted the removal of regolith and the development of thick breccia deposits during marine isotope stages mis 9 3 5 5 and 5 1 cave sediments were partially eroded whereas beach layers and related speleothems developed these are in fact the only marine isotope stages marked by a sea level position which in this mediterranean region was either close to or slightly higher than the present one

neogene to quaternary sedimentary basins in the south adriatic central mediterranean foredeeps and lithospheric buckling up to several kilometers deep sedimentary basins of neogene to quaternary age are found in the south adriatic between the apennines and the dinarides albanides they are the apennines foredeep the central adriatic basin and the south adriatic basin two regional seismic lines 260 and 170 km long across the entire system provide hitherto unavailable constraints on the kinematics and dynamics of basin development the apennine foredeep imaged along the lines formed in middle to late pliocene times through a rapid westward tilting of the basin floor a paleobathymetry of few kilometers was created in which allochthonous bodies were emplaced and sediments deposited unaffected by deformation and farther rotations the central and south adriatic basins formed in neogene to quaternary times and are both characterized by strong subsidence in their central parts gradually diminishing toward the edges in the sw and ne depocenters did not shift laterally through time subsidence rates increase through time and subsidence continued also following the end of main shortening episodes in the dinarides albanides the central and south adriatic basins form two crustal scale synclines with subsidence concentrated in their central parts basins geometries and subsidence patterns indicate that the adriatic crust has undergone episodes of buckling since miocene times wavelengths and amplitudes of such folds change along strike corresponding to mechanical changes of the folded medium

travel time tomography of the european mediterranean mantle down to 1400 km abstract the 3 d p wave velocity structure of the mantle below europe the mediterranean region and a part of asia minor is investigated this study is a considerable extension of an earlier tomographic experiment that was limited to imaging upper mantle structure only here the earth s volume under study encompasses the mantle to a depth of 1400 km and we increase the number of international seismological centre isc data for inversion by a factor of four by taking more years of observation and by including data from teleseismic events the most important departure from the earlier study is that we do not use the jeffreys bullen model as a reference model but an improved radially symmetric velocity model the pm2 model which is appropriate for the european mediterranean mantle our inversion procedure consists of two steps first the radial model pm2 is determined from the isc delay times by a nonlinear trial and error inversion of the data as opposed to the jeffreys bullen model the new reference model has a high velocity lithosphere a low velocity zone and seismic discontinuities at depths of 400 and 670 km next the isc data are corrected for effects related to the change in reference model and inverted for 3 d heterogeneity relative to the pm2 model we follow this two step approach to attain a better linearizable tomographic problem in which ray paths computed in the pm2 model provide a better approximation of the actual ray paths than those computed from the jeffreys bullen model hence the two step scheme leads to a more credible application of fermat s principle in linearizing the tomographic equations inversion results for the 3 d heterogeneity are computed for both the uncorrected isc data and for the pm2 data the data fit obtained in the two step approach is slightly better than in the inversion of isc data using the jeffreys bullen reference model a comparison of the tomographic results demonstrates that the pm2 data inversion is to be preferred to assess the spatial resolution an analysis is given of hit count patterns sampling of the mantle by ray paths and results of sensitivity tests with 3 d synthetic velocity models the spatial resolution obtained varies with position in the mantle and is studied both in map view and in cross section in the well sampled regions of the mantle the spatial resolution for larger scale structure can qualitatively be denoted as reasonable to good and at least sufficient to allow interpretation of larger scale anomalies a comparison is made of the results of this study with independent models of s velocity heterogeneity obtained in a number of investigations and with a prediction of the seismic velocity structure of the mantle computed from tectonic reconstructions of the mediterranean region in the context of this comparison interpretations of large scale positive anomalies found in the mediterranean upper mantle in terms of subducted lithosphere are given specifically addressed are subduction below southern spain below the western mediterranean and italy and below the aegean in the last region a slab anomaly is mapped down to depths of 800 km

active tectonics of the aegean region the aegean sea and its surrounding regions comprise one of the most rapidly deforming parts of the alpine himalayan mountain belt though the deformation of the belt as a whole is related to thc northward move ment of africa arabia and india relative to eurasia the tectonics of the aegean region itself is dominated by strike slip and extensional motions the actively deforming part of the aegean region is not large about 700 x 700 km2 compared with that in asia yet it has had an influence on our views of continental tectonics disproportionate to its size and comparable perhaps only to tibet fundamental contributions from the aegean have been made to many topics including

sea level and vertical motion of continents from dynamic earth models since the late cretaceous dynamic earth models are used to better understand the impact of mantle dynamics on the vertical motion of continents and regional and global sea level change since the late cretaceous a hybrid approach combines inverse and forward models of mantle convection and accounts for the principal contributors to long term sea level change the evolving distribution of ocean floor age dynamic topography in oceanic and continental regions and the geoid we infer the relative importance of dynamic versus other factors of sea level change determine time dependent patterns of dynamic subsidence and uplift of continents and derive a sea level curve we find that both dynamic factors and the evolving distribution of sea floor age are important in controlling sea level we track the movement of continents over large scale dynamic topography by consistently mapping between mantle and plate frames of reference and we find that this movement results in dynamic subsidence and uplift of continents the amplitude of dynamic topography in continental regions is larger than global sea level in several regions and periods so that it has controlled regional sea level in north and south america and australia since the late cretaceous northern africa and arabia since the late eocene and southeast asia in the oligocene miocene eastern and southern africa have experienced dynamic uplift over the last 20 to 30 m y whereas siberia and australia have experienced cenozoic tilting the dominant factor controlling global sea level is a changing oceanic lithosphere production that has resulted in a large amplitude sea level fall since the late cretaceous with dynamic topography offsetting this fall

aminostratigraphy of quaternary shorelines in the mediterranean basin the age and correlation of shorelines around the mediterranean basin have been addressed by analyzing the extent of isoleucine epimerization aile ile ratio in protein preserved in molluscan fossils collected from raised marine deposits the taxodont genera glycymeris and arca were selected as the primary taxa for this study because of their simple shell structure reproducible aile ile ratios and ubiquitous occurrence direct comparison of aile ile ratios in associated mollusks allows correlation of disjunct marine deposits and relative dating of sequential marine units in nearby areas that have similar thermal histories the thermal gradient across the mediterranean basin is however sufficiently high that shells from isochronous shorelines have significantly higher ratios at warmer than at cooler localities absolute dating primarily u series dates on corals directly associated with molluscan samples provides an independent calibration of the amino acid data and compensates for dissimilar thermal histories aile ile ratios in shells from 46 marine units cluster into 5 discrete groups c e f g and k that are related to positive sea level events interglacials interstadials associated with odd numbered deep sea isotopic stages the most complete sequences are in southern italy where group c ratios in glycymeris that average 0 30 are associated with the neotyrrhenian a post last interglacial late stage 5 high sea level event group e ratios 0 38 are associated with classical eutyrrhenian deposits from which four u series coral dates 126 7 ka substantiate the correlation to isotope substage 5e group f ratios 0 50 are associated with u series coral and mollusk dates between 200 and 300 ka the deposits are tentatively correlated with stage 7 deposits that have group g ratios 0 58 are correlated with stage 9 shells from lower pleistocene marine deposits that have ratios between 1 0 and 1 2 group k constrain the ages of the younger groups an exponential decrease in the epimerization rate inhibits resolution of the older events aile ile ratios in last interglacial deposits are similar in the northern and central region of the study area but increase sharply in southern sicily north africa and crete similar to the modern thermal gradient a lacuna between group g and group k is similar to gaps identified in california and alaska suggesting generally lower interglacial sea levels between stage 11 and sometime before the brunhes matuyama boundary

eocene to present subduction of southern adria mantle lithosphere beneath the dinarides we modeled global positioning system measurements of crustal velocity along a n13 e profile across the southern adria microplate and south central dinarides mountain belt using a one dimensional elastic dislocation model we assumed a n77 w fault strike orthogonal to the average azimuth of the measured velocities but we used a constrained random search algorithm minimizing misfit to the velocities to determine all other parameters of the model the model fault plane reaches the surface seaward of mapped sw verging thrusts of eocene and perhaps neogene age along the coastal areas of southern dalmatia consistent with sw migrating deformation in an active fold and thrust belt p wave tomography shows a ne dipping high velocity slab to 160 km depth which reaches the surface as adria dips gently beneath the foreland and becomes steep beneath the dinarides topographic high the thrust plane is located directly above the shallowly dipping part of the slab the pattern of precisely located seismicity is broadly consistent with both the tomography and geodesy deeper earthquakes down to 70 km correlate spatially with the slab and shallower earthquakes are broadly clustered around the geodetically inferred thrust plane the model fault geometry and loading rate ages of subaerially exposed thrusts in the fold and thrust belt and the length of subducted slab are all consistent with adria eurasia collision involving uninterrupted subduction of southern adria mantle lithosphere beneath eurasia since eocene time

u series dating by the tims technique of land snails from paleosols in the canary islands a sequence of seven superimposed paleosols developed on eolian calcarenites and alluvium was sampled on the island of lanzarote in order to examine the possibility of dating land snail shells by the u series method using a tims technique allowing measurement of u and th isotopes in very small samples in the lower six units the fossil shells yielded d allo l isoleucine a i ratios of about 0 5 and apparent ams 14c ages ranging from 41 000 to 34 000 yr b p indicating that most paleosols formed during a relatively short mid wurm humid episode the upper unit paleosol 7 yielded more variable a i ratios ranging from 0 6 to 0 2 and a younger 14c age 27 000 yr b p most samples contained enough u to allow the calculation of u series ages after correction for the presence of a detrital component in samples containing a few tens of ppb of u paleosols 1 2 3 6 and 7 the ages are strongly dependent upon the model used for the correction in samples containing more than 300 ppb of u paleosols 4 and 5 concordant ages of 31 000 1000 yr were obtained regardless of the correction model used u uptake in these shells occurred during one single early diagenetic phase soon after burial since shells of modern snails do not contain any significant amount of u the arid conditions subsequent to the mid wurm humid episode have likely ensured since then a fair closure of the radioactive system

a new view of italian seismicity using 20 years of instrumental recordings in this paper we show the seismicity of the past 20 years that occurred in italy and surrounding regions hypocentral locations have been obtained by using p and s wave arrival times from the ingv national and several regional permanent seismic networks more than 48 000 events selected from an original data set of about 99 780 are used to reconstruct the most complete seismic picture of the italian region so far the seismicity distribution allows inference on seismotectonics of this complex region of subduction versus continental collision our results clearly reveal the geometry of the adria and the ionian subduction and a continuous normal fault belt in the upper crust following the apennines mountain range the depth of the seismogenic layer is computed from the cut off of seismicity at depth and shows large variations along and across the seismic active regions earthquakes are generated by the different velocity of slab retreat and the subsequent asthenospheric upwelling d 2004 elsevier b v all rights reserved

new empirical relationships among magnitude rupture length rupture width rupture area and surface displacement source parameters for historical earthquakes worldwide are compiled to develop a series of empirical relationships among moment magnitude m surface rupture length subsurface rupture length downdip rupture width rupture area and maximum and average displacement per event the resulting data base is a significant update of previous compilations and includes the additional source parameters of seismic moment moment magnitude subsurface rupture length downdip rupture width and average surface displacement each source parameter is classified as reliable or unreliable based on our evaluation of the accuracy of individual values only the reliable source parameters are used in the final analyses in comparing source parameters we note the following trends 1 generally the length of rupture at the surface is equal to 75 of the subsurface rupture length however the ratio of surface rupture length to subsurface rupture length increases with magnitude 2 the average surface displacement per event is about one half the maximum surface displacement per event and 3 the average subsurface displacement on the fault plane is less than the maximum surface displacement but more than the average surface displacement thus for most earthquakes in this data base slip on the fault plane at seismogenic depths is manifested by similar displacements at the surface log linear regressions between earthquake magnitude and surface rupture length subsurface rupture length and rupture area are especially well correlated showing standard deviations of 0 25 to 0 35 magnitude units most relationships are not statistically different at a 95 significance level as a function of the style of faulting thus we consider the regressions for all slip types to be appropriate for most applications regressions between magnitude and displacement magnitude and rupture width and between displacement and rupture length are less well correlated and have larger standard deviation than regressions between magnitude and length or area the large number of data points in most of these regressions and their statistical stability suggest that they are unlikely to change significantly in response to additional data separating the data according to extensional and compressional tectonic environments neither provides statistically different results nor improves the statistical significance of the regressions regressions for cases in which earthquake magnitude is either the independent or the dependent parameter can be used to estimate maximum earthquake magnitudes both for surface faults and for subsurface seismic sources such as blind faults and to estimate the expected surface displacement along a fault for a given size earthquake

deflection gravity anomalies and tectonics of doubly subducted continental lithosphere adriatic and ionian seas three profiles across the southern adriatic and northern ionian seas span an intermediate foreland area that is or has recently been subducted both westward under the apennine calabrian thrust belt and eastward under the hellenide belt gravity and deflection data from the base of the pliocene along the three profiles are qualitatively similar to those predicted for a thin elastic sheet subject to end loads at both plate ends more detailed analysis of the profiles shows very good agreement between observations and predictions if the intermediate foreland lithosphere is treated as a thin elastic sheet with an effective elastic thickness between about 15 and 20 km equivalent to a flexural rigidity between 2 1022 and 6 1022 nm these results coupled with seismicity data suggest that active convergence within the hellenides extends as far north as southwestern yugoslavia analysis of the northernmost profile across the southern adriatic sea shows a well constrained elastic plate thickness of 14 km and an initial water depth prior to loading of about 1 km the distance between the two subduction systems on this profile is estimated at about 275 km analysis of the two more southerly profiles yields a minimum effective elastic plate thickness of about 15 km but no maximum value could be determined the initial water depths for these two profiles are well constrained at 1 3 and 1 6 km prior to loading and the distance between the two subduction systems is estimated at about 175 km on both profiles along the northwest trend of the two opposing subduction systems the change in distance between the two systems occurs abruptly and the hellenic subduction system appears to be segmented into a series of northwest trending roughly linear subduction segments the calculated deflection profiles also show pronounced asymmetry on the northernmost profile and an opposite sense of asymmety on the southernmost profile

pleistocene sea level changes sapping processes and development of valley networks in the apulia region southern italy abstract the central area of the apulia region is characterized by a network of valleys with peculiar features locally called gravine or lame they are short straight valleys deeply incised in plio pleistocene calcareous sandstones and in mesozoic limestones these characteristic valleys cut a staircase of marine terraces a series of valley generations is recognisable each one of them leading to the internal margin of a marine terrace representing its base level morphological features and hydrogeological conditions suggest that sapping processes were responsible for the development of the valley network as the aquifer rests on seawater intruding from the nearby coastal area sapping processes were enhanced during interglacial high sea level stands so that each ancient coastline is marked by its own generation of valleys however the longest and deepest valleys formed at the ionian side during ois 7 this is due mostly to a fast sea level rise accompanied by very humid climatic conditions that increased the hydraulic head at the springs and the intensity of sapping processes sapping valleys could be useful for regional correlation of marine terraces and as indicators of relict coastlines at present placed below sea level

construction of a seismotectonic model the case of italy procedures for constructing a seismotectonic model of italy designed to be used as a basis for hazard assessment are described the seismotectonic analysis has essentially been based on a gis aided cross correlation of three data sets concerning the 3 d structural model of italy and surrounding areas the space distribution of historical and present seismicity the kinematic model of the central mediterranean region referred to the last 6 ma and including the available information on the present day plate motion and stress field the seismicity pattern in the study area is controlled by a quite complex geodynamic framework which includes continent continent convergence alps and dinarides with development of a neutral arc bordering the plate margins plate divergence across margins characterized by passive slab sinking northern apennines and calabrian arc with development of backarc basins northern tyrrhenian sea and southern tyrrhenian sea flanked by forelandward migrating thrust belt foredeep systems plate divergence across a margin previously characterized by lithosphere sinking and afterwards discharged from the subducted slab southern apennines with development of quite peculiar rift processes within the inactive thrust belt transpression northern sicily due to the combined effect of plate convergence africa europe and high rate flexure hinge retreat of an intervening plate adria microplate with high angles between the respective slip vectors intraplate strain partition and fault activity mainly combined strike slip and thrust motions possibly in correspondence of inverted structures the results of the seismotectonic analysis are synthesized in a zonation of italy in which every delimited zone corresponds to the surface projection of a kinematically homogeneous segment of a seismogenic fault system in cornell type hazard evaluations every polygon should be considered as a homogeneous source zone seat of randomly distributed earthquakes a homogeneous mechanical behaviour of an entire zone and a random earthquake distribution within a single source zone obviously represent oversimplified assumptions since every zone includes one or more master fault segments responsible for the greatest events in the area and several second order associated faults responsible for the background minor seismicity therefore major faults and background seismicity should be treated separately nevertheless the oversimplified assumption of homogeneous seismic zones was the price the authors consciously paid to produce in a reasonably short time a homogeneous product relative to the entire national territory suitable for earthquake hazard evaluation and for decisions regarding risk mitigatiton

differential uplift along the northern margin of the central anatolian plateau inferences from marine terraces abstract emerged marine terraces and paleoshorelines along plate margins are prominent geomorphic markers that can be used to quantify the rates and patterns of crustal deformation the northern margin of the central anatolian plateau has been interpreted as an actively deforming orogenic wedge between the north anatolian fault and the black sea here we use uplifted marine terraces across principal faults on the sinop peninsula at the central northern side of the pontide orogenic wedge to unravel patterns of quaternary faulting and orogenic wedge behavior we leveled the present day elevations of paleoshorelines and dated marine terrace deposits using optically stimulated luminescence osl to determine coastal uplift the elevations of the paleoshorelines vary between 4 0 2 and 67 1 4 m above sea level and osl ages suggest terrace formation episodes during interglacial periods at ca 125 190 400 and 570 ka corresponding to marine isotopic stages mis 5e 7a 11 and 15 mean apparent vertical displacement rates without eustatic correction deduced from these terraces range between 0 02 and 0 18 mm a with intermittent faster rates of up to 0 26 mm a we obtained higher rates at the eastern and southern parts of the peninsula toward the hinterland indicating non uniform uplift across the different morphotectonic segments of the peninsula our data are consistent with active on and offshore faulting across the sinop peninsula when integrated with regional tectonic observations the faulting pattern reflects shortening distributed over a broad region of the northern margin of the central anatolian plateau during the quaternary

neogene quaternary tectonic evolution of the southern apennines 1 in this paper we present a study of a segment of the southern apennine mountain belt which extends from the pollino mountain range to the south and the sele valley to the north combining regional data and structural information with the results based on the interpretation of several seismic reflection lines and many deep well logs three regional cross sections have been constructed the cross sections highlight the overall architecture of the orogenic belt which is constituted by a thin tectonic layer of allochthonous nappes represented by remnants of the neotethyan accretionary wedge e g liguride and sicilide units resting above a thick imbricated thrust belt this latter comprises distinct units represented by platform carbonates western platform monte alpi costamolina and tempa rossa units and pelagic basin domains lagonegro campomaggiore and faeto units deriving from the late tortonian quaternary deformation of the adria paleomargin the restoration of the three cross sections furnished information on the primary geometry of the adria paleomargin which was characterized by the occurrence of a large platform domain dissected by distinct pelagic basins with complex and irregular margins represented by pelagic embayments and platform promontories developed during the mesozoic and the late cretaceous tertiary times the reconstructed geometry of the paleomargin provided moreover useful insights to evaluate the mode of deformation and the rates of shortening of the thrust belt and to explain the neogene stratigraphy of the distinct platform domains the mode of deformation of this portion of the southern apennines was dominated by the occurrence of crustal thrusts located along previous weakness zones represented by the boundaries between platform and pelagic domains these crustal thrusts caused the complete closure of the basin areas and the direct overthrusting of the different buoyant platform domains with contractional rates characterized by values ranging from 3 1 to 4 3 cm yr finally a geodynamic model in which the southern apennine mountain belt is considered the result of lateral extrusion produced by the indentation of the pelagian block and by the consequent opening of the tyrrhenian sea is also proposed

foredeep geometries at the front of the apennines in the ionian sea central mediterranean abstract a new regional seismic section in the ionian sea across the apennines belt and related foreland shows how the present foredeep geometry may be an example for interpreting discontinuous tilted and deformed earlier basins now incorporated in the internal parts of the accretionary wedge onlap stratal terminations of the foredeep sediments on the foreland monocline may simulate downlap geometries once involved and tilted by back thrusting the geometry of the ionian foredeep is controlled by the dip of the regional monocline and internally by the variable dip and length of the limb of the external fold which may be either foreland verging or hinterland verging the generation of a new fold within the foredeep splits the basin into a new foredeep toward the foreland and a thrust top basin toward the hinterland the thrust top basin dimension is primarily controlled by the distance between the two folds and related thrusts at its margins the foredeep in its overall history is composed by a series of concave heterogeneous lenses progressively displaced and piled up toward the foreland to the east the formation of each sedimentary lens is controlled by the development of a new fold and the contemporaneous retreat of the regional monocline which creates new accommodation space the complex 3d geometry of the apennines foredeep mainly results from lateral variations of the latter parameters as well as variations in sediment supply and eustasy

crustal velocity and strain rate fields in italy and surrounding regions new results from the analysis of permanent and non permanent gps networks summary we present a new geodetic velocity solution for italy and the surrounding areas obtained from an analysis of continuous and survey mode global positioning system observations collected between 1991 and 2002 we have combined local regional and global networks into a common reference frame velocity solution providing a new detailed picture of the regional scale deformation field in the central mediterranean our velocity estimates are computed with respect to a new stable eurasian reference frame constraining the kinematics of the greater african eurasian plate boundary system in the study area we provide strain rate values for the main seismotectonic districts which are in good agreement with the seismic deformation inferred from earthquake focal mechanisms the southern tyrrhenian area calabria the apennines the southeastern alps the southern dinarides and the albanides display deformation rates at the order of 20 30 nanostrain yr 1 the corsica sardinia block moves according to eurasian plate motions and there is no indication that the opening of the tyrrhenian is still active the pelagian and sicilian domains are separated by a northwest southeast discontinuity the sicily channel rifted area and marginally significant relative motion between the pelagian plateau and the african plate is also observed the southern tyrrhenian is affected by north south compression and accommodates up to 50 per cent of the africa eurasia relative plate motion whereas the calabrian arc exhibits 2 mm yr 1 northwest southeast extension the observed deformation pattern suggests the presence of a major approximately north south tectonic discontinuity separating the sicilian and calabrian domains an extensional boundary observed along peninsular italy coincides with the distribution of seismogenic faults along the axis of the apennines this boundary separates a tyrrhenian and an adriatic domain with diverging velocities orientated north nnw ward and northeastward respectively the apennines are extending perpendicularly to the chain axis at rates of less than 3 mm yr 1 and only in the outer northern apennines indications of active shortening are observed insignificant deformation is observed in the western po plain and the western alps while the central and eastern alps display north south shortening the eastern adriatic domain is shortening perpendicular to the dinaric front with strain rates increasing from north to south the locus of collision between the aegean balkan system and the adriatic and ionian domains is marked by the kephalonia fault system which accommodates up to 20 1 mm yr 1 of right lateral motion the deformation pattern observed in the peri adriatic domain is well described by a counter clockwise rotation of the adriatic microplate around a pole located in the western alps

orogens and slabs vs their direction of subduction abstract subduction zones appear primarily controlled by the polarity of their direction i e w directed or e to nne directed probably due to the westward drift of the lithosphere relative to the asthenosphere the decollement planes behave differently in the two end members in the w directed subduction zone the decollement of the plate to the east is warped and subducted whereas in the e to nne directed it is ramping upward at the surface there are w directed subduction zones that work also in absence of active convergence like the carpathians or the apennines w directed subduction zones have shorter life 30 40 ma than e or ne directed subduction zones even longer than 100 ma the different decollements in the two end members of subduction should control different ptt paths and therefore generate variable metamorphic assemblages in the associated accretionary wedges and orogens these asymmetries also determine different topographic and structural evolutions that are marked by low topography and a fast eastward migrating structural wave along w directed subduction zones whereas the topography and the structure are rapidly growing upward and expanding laterally along the opposite subduction zones the magmatic pair calc alkaline and alkaline tholeiitic volcanic products of the island arc and the back arc basin characterise the w directed subduction zones magmatic rocks associated with e or ne directed subduction zones have higher abundances of incompatible elements and mainly consist of calc alkaline shoshonitic suites with large volumes of batholithic intrusions and porphyry copper ore deposits the subduction zones surrounding the adriatic plate in the central mediterranean confirm the differences among subduction zones as primarily controlled by the geographic polarity of the main direction of the slab the western margin of the adriatic plate contemporaneously overridden and underthrust europe toward the west to generate respectively the alps and the apennines while the eastern margin subducted under the dinarides hellenides these belts confirm the characters of the end members of subduction zones as a function of their geographic polarity similarly to the pacific subduction zones

coastal towers and historical sea level change along the salento coast southern apulia italy abstract the perimeter of salento peninsula southern apulia italy is studded by numerous coastal towers built in the xvi century aiming to create an early warning system against pirates attacks at present two of them fiumicelli tower on the adriatic coast and pali tower on the ionian one have bases a few decimeters below mean sea level the unusual position of both coastal towers can be explained by taking into account geomorphological features of the coastal area and the relative sea level change during the last 500 years geomorphological analysis reveals the occurrence directly in front of the two coastal towers of a wide rocky shore platform to about 1 m depth if a mean sea level about 0 6 1 0 m below present position is supposed at the time of coastal tower construction the wide shore platform would be slightly above sea level and would be able to protect the towers from sea storms furthermore by comparing these data with the results of available glacio hydro isostatic models for southern apulia during the late holocene it is possible to postulate tectonic subsidence of the salento coastal area during the last five centuries the collated data establish the quaternary tectonic history of salento peninsula it experienced a period of general subsidence during the lower pleistocene that was interrupted by rapid uplift during the middle pleistocene uplift stopped at mis 9 3 about 330 ka replaced by a phase of substantial stability which lasted until the late pleistocene holocene finally active tectonic subsidence has affected the coast of salento peninsula during the last four millennia probably in response to the recent doming of the region

deformation of the 125 ka marine terrace in italy tectonic implications in peninsular italy marine terraces and shorelines created during oxygenisotope substage 5e known historically as the tyrrhenian highstand provide a reliable and homogeneous datum of vertical motions during the past 125 000 years published accounts of 121 locations on the tyrrhenian inner edge were reinterpreted and used to calculate both local and regional uplift rates the data show arching of southern italy between the tyrrhenian and the adriatic coasts and of the calabrian arc between the sangineto and the longi taormina tectonic lineaments at rates of up to 1 2 mm yr for the past 125 ka they also suggest that the present configuration of the southern apennines is the product of post early pleistocene regional uplift superimposed on tortonian to early pleistocene thrusting uplift patterns are characterised by different wavelength in different geodynamic settings suggesting a close link with the depth of the causative tectonic sources

interglacial sea levels abstract isotopic curves have been used as approximative estimators of global sea level calculations of the amplitude of sea level variations during interglacials especially for the last interglacial are based on the study of emerged coral terraces the application of different dating methods shows great uncertainty about the length of each interglacial and also about the number chronology and altitude of the different highstands that occur during each interglacial data of raised marine terraces from areas with different geodynamic behaviour bermudas bahamas peru chile italy and spain are summarized in order to analyze the relationships between sea level and interglacial stages two interglacials have been identified for the early pleistocene represented by two marine terraces with different highstands during the early middle pleistocene an interglacial with several highstands is recorded in uplifted areas during isotopic stage 11 at least one highstand with sea level equal or higher than present has been recorded similar sea level behaviour can be suggested for isotopic stage 9 all the analyzed areas record two highstands during isotopic stage 7 when warm equatorial fauna migrate into the mediterranean during isotopic substage 5e at least two highstands took place with evidence of lowstands between them and at least one highstand during substage 5c with similar sea level height above present msl except in barbados and bermuda during substage 5a at least one highstand has been recorded

comparison of earthquake scaling relations derived from data of the instrumental and preinstrumental era estimates of surface rupture displacement and magnitude for crustal earthquakes from the preinstrumental era pre 1900 tend to be greater than the corresponding estimates derived from modern scaling relations we investigate this tendency using an expanded and updated version of the earthquake dataset of wells and coppersmith 1994 to fit regression relations of moment magnitude on surface rupture length and rupture area and average surface displacement on surface rupture length separate relations are fitted to preinstrumental and instrumental data and the results compared to the equivalent relations of wells and coppersmith we find that our relations for instrumental data remove some but not all of the differences between the preinstrumental data and the relations of wells and coppersmith we attribute the remaining differences largely to natural censoring of surface displacements less than about 1 m and surface rupture lengths less than about 5 km from the dataset for the preinstrumental era because regressions constructed from similarly censored instrumental data are indistinguishable from the preinstrumental regressions since the regressions for our censored instrumental data i e restricted to moderate to large earthquakes are different from regressions for our complete dataset of instrumental earthquakes and from the regressions of wells and coppersmith both with a larger proportion of small to moderate earthquakes the results may indicate that large earthquakes have different scaling relationships from those of smaller earthquakes

geodetic determination of the kinematics of central greece with respect to europe implications for eastern mediterranean tectonics we use a new satellite laser ranging global positioning system slr gps solution at seven sites in anatolia and aegea to obtain a better definition of the extrusion motion of the anatolian aegean block with respect to europe we show that this motion can be described in a first approximation by a counterclockwise rotation which transfers most of the motion of arabia to anatolia we combine 78 displacement vectors obtained at common points of two triangulation nets measured in central greece in 1895 and 1975 with the slr gps measurements to compute the velocity field over greece with respect to europe these measurements indicate that central greece is a zone of extension between the anatolian aegean counterclockwise rotation to the south and the northern greece clockwise rotation to the north this extension is principally localized within the gulf of corinth to the east but is distributed to the west we then extrapolate this velocity field to the whole aegea and western anatolia using recently published gps results as well as the slr results the narrow dextral north anatolian fault which limits the velocity field to the north progressively gives way to a much wider boundary zone where extension becomes dominant we show that the collision between the mediterranean ridge and africa began 3 6 ma and we describe the modifications that this collision has produced on the kinematic pattern both in aegea and on the mediterranean ridge

comment on late cenozoic uplift of southern italy deduced from fluvial and marine sediments coupling between surface processes and lower crustal flow by westaway r and bridgland d quaternary international 175 86 124 abstract we consider it opportune to comment on some of the statements proposed by westaway r and bridgland d 2007 in their paper late cenozoic uplift of southern italy deduced from fluvial and marine sediments coupling between surface processes and lower crustal flow quaternary international 175 86 124 with particular reference to the first half of the paper focusing on the geomorphological analysis of the pleistocene marine and fluvial terraces that occur along the ionian coastal area of the basilicata region southern italy as authors of some of the papers cited in westaway r bridgland d 2007 late cenozoic uplift of southern italy deduced from fluvial and marine sediments coupling between surface processes and lower crustal flow quaternary international 175 86 124 we wish to point out several significant inaccuracies in their paper which are generally due to the misunderstanding or misuse of literature data and which regard i both the vertical distribution and the timing of the whole ionian marine terrace sequence ii the correlation between marine terraces and marine isotopic stages mis iii the interaction between uplift and erosion processes in basilicata and iv the morphogenic model of the fluvial terraces of the agri river it is our opinion that the late cenozoic uplift magnitudes rates and modelling proposed by the authors for this key area of southern italy using such unreliable data are therefore to say the least questionable

ionian marine terraces of southern italy insights into the quaternary tectonic evolution of the area 1 new detailed morphotectonic analyses of a well exposed flight of marine terraces along the ionian coast of southern italy has been carried out the area represents a key transect for investigating the middle late quaternary evolution of the southern apennines chain foredeep foreland geodynamic system a major result of the research is the reconstruction of a virtually complete 3d geometry of the marine surfaces along a coastal sector of ca 70 km which 1 documents the occurrence of 18 paleo shorelines and 2 provides evidence for a strong regional uplift affecting the investigated area following a systematic critical review of literature relating to geochronological data integrated with a morphogenetic model based on the interaction between tectonic uplift and eustatic sea level changes the different terraces are correlated to as many highstand sea level peaks dating the highest oldest terrace to ca 600 ka mis 15 the vertical and horizontal distribution of the terraces show a general convergence of the paleo shorelines toward nne which indicates a decreasing trend in differential uplift in that direction ranging from almost 2 mm a in the southwestern sector to about 0 2 mm a in the northeastern sector detailed mapping and 3d reconstruction also emphasize the partitioning of the area into three distinct sectors characterized by different tilting rates this behavior is likely caused by the combined role and activity of three major tectonic structures working at different scales and rates including 1 the reactivation of an out of sequence thrust 2 sliding along the basal detachment of the external apennines wedge and 3 a lithospheric scale duplexing crustal or deeper as a major conclusion within the external sector of the southern apennines chain and its foredeep regional shortening and a contractional tectonic regime persisted throughout the whole quaternary and it is probably still active

u series measurements in tyrrhenian deposits from mallorca further evidence for two last interglacial high sea levels in the balearic islands the campo de tiro type section for the tyrrhenian ecostratigraphic beds of the balearic islands shows four indurated littoral conglomerates and beach rocks unconformably superimposed the lower two units 1 and 2 are separated by a thin layer of reddish continental silts both contain a typical eutyrrhenian fauna whereas a neotyrrhenian fauna characterizes the overlying units 3 and 4 thu measurements by thermal ionisation mass spectrometry on mollusk shells from these deposits yielded ages of 135 ka unit 1 117 ka units 2 and 3 and a scatter of ages around 100 ka unit 4 the stratigraphic relationships and thu data indicate i that uranium was uptaken by mollusks shells but arca sp each time during a relatively short early diagenetic interval before cementation ensured a fair closure of the radioactive system ii two high sea stands characterized the last interglacial isotopic substage 5e of the balearic islands area iii the duration of this episode was 17 ka and iv the change in faunal assemblages and disconformity observed between units 2 and 3 are due to fluctuations in sea level and surface water conditions which occurred during the second high sea level episode of the last interglacial

crustal structure in the southern apennines from teleseismic receiver functions while the upper crustal structure of the southern apennines is known lack of control on the deep structure allows competing thin skinned and thick skinned models of the orogen in thin skinned models the detachment decouples a stack of rootless nappes from the basement in thick skinned models basement is involved in the most recent phase of thrusting to examine crustal structure we use teleseismic data from the calabria apennine tyrrhenian subductionaccretion collision network cat scan array in southern italy we use receiver functions rf processed into a common conversion point stack to generate images of the crust interpretation and correlation to geological structure are done using inversions of individual station rfs we focus on a shallow discontinuity where p to s conversions occur in the foreland it corresponds to velocity jumps between carbonate and clastic strata with basement a similar interpretation for the apennines provides the most parsimonious explanation and supports a thick skinned interpretation in a thick skinned reconstruction the amount of shortening is much smaller than for a thin skinned model this implies considerably less pliocene pleistocene shortening across the apennines and suggests an east southeast motion of the calabrian arc subparallel to the southern apennines rather than a radial expansion of the arc

the southern tyrrhenian subduction zone deep geometry magmatism and plio pleistocene evolution abstract we report on a high resolution vp vp vs and qp model of the southern tyrrhenian subduction zone obtained by the inversion of p and s wave arrival times and t values from intraslab seismicity the arcuate shape of the southern apennines calabrian arc sicilian maghrebides is perfectly mirrored by two rather continuous low and high vp bands lying beneath the belt system at ca 25 and 100 km respectively between 100 and 300 km two independent high vp slabs lie beneath the neapolitan region and the southern tyrrhenian sea separated by unperturbed mantle we suggest that the ca 150 km wide slab window beneath the southern apennines opened after a tear occurring within a composite subduction system formed by the apulian continental lithosphere and the ionian oceanic slab the abrupt slab rupture induced ultrafast southeastward retreat of the ionian slab and the 19 cm yr spreading of the back arc oceanic marsili basin between ca 2 1 and 1 6 ma ago the 25 km low vp zone beneath the arc denotes continental upper crustal rocks below the chain its striking continuity requires a unique orogenic wedge at 25 km depth below the southern apennines the calabrian arc and the sicilian maghrebides the alternative explanation would imply the ubiquitous occurrence of autochthonous lower plate rocks at 25 km depth i e a puzzling autochthonous continental calabria the ionian slab beneath calabria shows high vp high qp and low vp vs anomalies typical of old oceanic lithosphere intermediate depth seismicity is concentrated within its thin oceanic crust suggesting the occurrence of vigorous metamorphism the slab dehydration promotes the melting of the overlying mantle as testified by high vp vs and low qp anomalies between the slab and the aeolian magmatic arc

an active oblique contractional belt at the transition between the southern apennines and calabrian arc the amendolara ridge ionian sea italy high resolution single channel seismic and multibeam bathymetry data collected at the amendolara ridge a key submarine area marking the junction between the apennine collision belt and the calabrian subduction forearc reveal active deformation in a supposedly stable crustal sector new data integrated with existing multichannel seismic profiles calibrated with oil exploratory wells show that middle to late pleistocene sediments are deformed in growth folds above blind oblique reverse faults that bound a regional pop up data analysis indicates that 10 to 20 km long banks that top the 80 km long nw se trending ridge are structural culminations above en echelon fault segments numeric modeling of bathymetry and stratigraphic markers suggests that three 45 dipping upper crustal 2 10 km fault segments underlie the ridge with slip rates up to 0 5 mm yr segments may be capable with m 6 1 6 3 earthquakes although an unknown fraction of aseismic slip undoubtedly contributes to deformation the fault array that bounds the southern flank of the ridge amendolara fault system parallels a belt of mw 4 7 strike slip and thrust earthquakes which suggest current left oblique reverse motion on the array the eastern segment of the array shows apparent morphologic evidence of deformation and might be responsible for mw 5 2 historic events late pliocene quaternary growth of the oblique contractional belt is related to the combined effects of stalling of adriatic slab retreat underneath the apennines and subduction retreat of the ionian slab underneath calabria deformation localization was controlled by an inherited mechanical interface between the thick apulian adriatic platform crust and the attenuated ionian basin crust

a proposal for the kinematic modelling of w dipping subductions possible applications to the tyrrhenian apennines system in w dipping subduction zones there is a general eastward progression of the back arc basin accretionary wedge foredeep complex with the forward progression early stages of the complex are revealed by slices of upper crust and sedimentary cover abandoned to the west left floating above a new section of mantle a major shear zone should form at the new moho separating upper crust slices of earlier accretionary stages and the eastward flowing mantle the mantle wedging at the top of the subduction plane could be responsible for the uplift of the central parts of the belt the retreating of the subduction hinge is interpreted as due to the push generated by the eastward mantle flow detected in the hot spot reference frame the foredeep depth is mainly a function of the radius of curvature of the subduction hinge the frontal wedge is constructed from the stacking of the upper layers of the subducting plate and the syntectonic clastics that fill the foredeep which are progressively involved in thrusting and later by extension in order to preserve volume balance the lithosphere of the eastern plate before subduction has to be the same size as that which has been subducted due to the longer length of the arc with respect to the original length of the linear margin between the two converging plates laterally stretched subducted lithosphere is predicted at depth w dipping subductions usually have a short life probably due to their inherent capability to produce new lateral heterogeneities of the lithosphere the thin back arc which are a key factor in controlling and generating new subductions both e and w dipping this model is applied to the apennines tyrrhenian sea system

fault activity and marine terracing in the capo vaticano area southern calabria during the middle late quaternary abstract the capo vaticano peninsula is a structural high bordered by several normal fault segments mainly striking ne sw and wnw ese and belonging to the so called siculo calabrian rift zone both the two fault systems extend in the tyrrhenian offshore and show recent activity in the capo vaticano peninsula six orders of marine terraces with their preserved paleoshorelines and a top surface have been recognised they form a continuous set of morphological elements ascribed to the last seven principal high stands of the eustatic curve occurred from 330 to 60 kyr on the basis of new chronological data available in the recent literature the morphotectonic analysis of the paleoshorelines allowed recognition of a deformation pattern characterised by a northeastward tilting of the area and to quantify the uplift rates moreover vertical slip rates ranging between 0 25 and 2 5 mm yr have been calculated for a wnw ese trending fault segment the coccorino fault in this structural framework the late quaternary uplift of the capo vaticano peninsula can be related to the activity of both the ne sw and wnw ese striking normal fault systems added to the regional component of uplift the recent activity of these structures is also suggested by the 1905 seismic event that occurred offshore of the capo vaticano peninsula

neogene quaternary evolution of the offshore sector of the southern apennines accretionary wedge gulf of taranto italy abstract southern apennines represent a collisional orogenic belt whose compressional regime is commonly assumed to have ceased during middle quaternary on the other hand to the south the calabria arc is still characterized by subduction and the principal aim of the present research is to shed some light on the space and time transition from the ceased collision to the active subduction accordingly we investigated the offshore sector of the southern apennines accretionary wedge corresponding to the taranto gulf to gain insights into the offshore accretionary wedge we reconstructed a 3d geological and tectonic model by interpreting a grid of 40 seismic reflection lines 1100 km 80 intersections within an area of ca 104 km2 calibrated with 17 wells the geometric and chronological constraints allow documenting a systematic messinian quaternary thrust migration from internal towards external sectors of the wedge the migrating deformational process was essentially associated with a leading imbricate thrust system with a general ne younging direction where we could recognize and distinguish some major advancing phases characterized by alternating fast thrust propagation events and strain accumulation periods within the wedge this process is well emphasized by the jump of the foredeep and piggy back basins the ne wards wedge migration was also associated with a lithospheric scale flexural folding that generated a set of normal faults striking parallel to the coeval thrusts likely reactivating optimally oriented structures inherited from mesozoic events finally a persisting thrust activity up to the latest quaternary and possibly up to present in correspondence of the externalmost sector of the accretionary wedge has been documented and explained in terms of strain partitioning in the frame of a recent oblique convergence the results of this research have possible implications for the seismic hazard assessment of the broader region which is possibly greater than previously assumed

new gps constraints on the africa eurasia plate boundary zone in southern italy 1 southern italy is a key area for understanding the tectonic processes in the africa eurasia collision zone we analyze new gps measurements carried out between 1994 and 2001 the results are presented in terms of time series trajectories and velocities of crustal motion as well as a geodetic strain rate field while central italy corsica sardinia and the tyrrhenian sea move like the eurasian plate the overall motion of the sicily rift zone region matches african plate motion unexpected are the north northwest directed motions of northeastern sicily and the eolian islands most striking on the deformation field are a north south oriented compression along the northern sicilian coast compression between apulia and northwestern greece as well as extension in the sicily rift zone and the interior of sicily

the age of late pleistocene shorelines and tectonic activity of taranto area southern italy abstract the results of isoleucine epimerization ratios in pelecypods glycymeris sp arca sp and cerastoderma sp and u series dating of bivalves and cladocora caespitosa sampled from different late pleistocene units in the cheradi islands and in the coastal areas of mar piccolo and mar grande near taranto apulia region italy are presented u series measurements on pelecypods and on corals directly associated with mollusc samples provide an independent calibration of amino acid data the d l ratios of isoleucine show a strong correlation with age and thus may be considered as a predictive dating technique this correlation also supports the reliability of u series ages obtained for molluscs these results including the stratigraphic position the lithological lateral continuity the morphological evidence and the palaeontological characteristics of the various units made it possible to attribute them to different marine trangressive phases referable to oxygen isotope stages ois 5e c 5a and 3 no evidence of land emersion between ois 5e and 5c has been found in the area pinkish red sands deposits located above present sea level 1 m have been referred to ois 3 the late pleistocene morphological evolution and uplift of a complex area between the apulian foreland and the bradanic foredeep have been reconstructed due to the lack of incontestable indicators of past sea level stands the facies analysis has been performed on u series dated 89 8 ka ois 5c shoreline north of mar piccolo and an uplift rate ranging from 0 21 0 27 mm yr has been calculated

three dimensional model of hellenic arc deformation and origin of the cretan uplift 1 the hellenic arc of greece is the most seismically active part of europe but little is know about its mechanics we modeled deformation along the arc using a finite element model the model was intended to capture large scale 3 d structure of nubian plate subduction beneath the aegean block and its deformational consequences the shape of the interface was developed using mapped traces at the surface and earthquake hypocenters at depth model block motions were constrained by recent compilations of gps velocity vectors we simulated a 10 ka period of convergence between nubia and the aegean and calculated the strain field in the overriding plate as well as the spatial distribution and orientation of differential stress 1 3 from these calculations we derived testable quantities such as the expected seismic moment rate on the interplate contact uplift pattern and distribution of strain modes our relatively simple model broadly reproduced observed uplift patterns earthquake activity and loci of extension and contraction the model showed a localization of uplift near the island of crete where the fastest aegean uplift rates are well documented comparison of calculated expected seismic moment and observed earthquake catalogs implies a nearly fully coupled interplate contact on the basis of our modeling results we suggest that south aegean deformation is driven primarily by the fast moving 33 mm a 1 aegean upper plate overriding a nearly stalled 5 mm a 1 nubian lower plate this tectonic setting thus more closely resembles a continental thrust than it does a typical oceanic subduction zone

lower adriatic sea seismic sequence january 1986 spatial definition of the seismogenic structure abstract in january 1986 a swarm like seismic sequence main shock m l 4 8 took place in the lower adriatic sea this sequence was recorded by the italian telemetered seismological network using a digital acquisition system using additional data collected by other italian yugoslavian and albanian institutions 15 shocks of the sequence were located by means of the master event technique and for two of them a focal mechanism solution was obtained we attempted to frame our results within the knowledge available in the literature the adriatic microplate is regarded by many authors as a whole block nevertheless it exhibits moderate seismicity the question has arisen as to whether it can be considered an african promontory or whether it behaves independently the area actived by the sequence is rather small less than 10 km in diameter owing to the low level of seismic energy release and does not show any particular trends the focal mechanisms are consistent with the recent stress field in the adriatic area inferred from previous studies which indicate a compression axis oriented ne sw

how do sea level curves influence modeled marine terrace sequences abstract sequences of uplifted marine terraces are widespread and reflect the interaction between climatic and tectonic processes at multiple scales yet their analysis is typically biased by the chosen sea level sl curve here we explore the influence of quaternary sl curves on the geometry of marine terrace sequences using landscape evolution models lems first we modeled the young rapidly uplifting sequence at xylokastro corinth rift

crustal motion and deformation in greece from a decade of gps measurements 1993 2003 abstract the hellenic plate boundary region located in the collision zone between the nubian arabian and eurasian lithospheric plates is one of the seismo tectonically most active areas of europe during the last 15 years gps measurements have been used to determine the crustal motion in the area of greece with the aim to better understand the geodynamical processes of this region an extended reoccupation network covering whole greece has been measured periodically in numerous gps campaigns since the late eighties and a continuous gps network has been operated in the region of the ionian sea since 1995 in this paper we present a new detailed high quality solution of continuous and campaign type measurements acquired between 1993 and 2003 during the gps processing a special effort was made to obtain consistent results with highest possible accuracies and reliabilities data of 54 mainly european igs and euref sites were included in the gps processing in order to obtain results which are internally consistent with the european kinematic field and order to allow for a regional interpretation after an overview of the results of the igs euref sites the results from more than 80 stations in greece are presented in terms of velocities time series trajectories and strain rates previous geodetic geological and seismological findings are generally confirmed and substantially refined new important results include the observation of deformation zones to the north and to the south of the north aegean trough and in the west hellenic arc region arc parallel extension of about 19 mm yr along the hellenic arc and compression between the ionian islands and the greek mainland due to continuous long term observations of 4 8 years it was possible to extract height changes from the gps time series in greece we observe a differential subsidence of the order of 2 mm yr between the northern and central ionian islands across the kefalonia fault zone the differential subsidence of the central ionian islands with respect to the northwestern greek mainland amounts to 4 mm yr

late cenozoic uplift of southern italy deduced from fluvial and marine sediments coupling between surface processes and lower crustal flow abstract we investigate the rates and magnitudes of late pliocene pleistocene uplift at key localities in the southern italian regions of basilicata and calabria using fluvial and marine terraces these rates show strong lateral variations reaching maxima of 1 mm a 1 or more in the southern apennines which have uplifted by many hundreds of metres since the late early pleistocene and by well over 1 km since the middle pliocene integrated study has been facilitated by the realisation that altitudes of river terraces in this region require substantial correction for downstream channel lengthening given the rapid coastal progradation that is occurring before they can be compared with altitudes of marine terraces these high rates of uplift and the corresponding rates of subsidence of the sea floor in adjacent offshore localities are explained as consequences of coupling between erosion and sedimentation by induced flow in the lower continental crust this coupling being particularly strong due to the narrowness of the southern part of the italian peninsula numerical modelling indicates that time averaged and spatially averaged erosion rates in this region have been 0 5 mm a 1 since the early middle pleistocene less than the regional uplift rates indicating that the landscape is not in a steady state although southern italy lies within a plate boundary zone along which the african plate is subducting and within which the continental crust is extending the observed vertical crustal motions are nevertheless controlled by surface processes in particular across much of this region crustal extension is shown to be a much less important factor than onshore erosion in driving the observed rates of vertical crustal motion

paleoenvironmental changes during sapropel 19 i cycle 90 deposition evidences from geochemical mineralogical and micropaleontological proxies in the mid pleistocene montalbano jonico land section southern italy an integrated micropaleontological geochemical and mineralogical study has been performed across the mid pleistocene sapropel 19 i cycle 90 from the montalbano jonico land section southern italy to reconstruct the paleoenvironmental conditions at time of its formation the sapropel interval is characterized by two oxygen depletion phases phase a and c interrupted by a temporary re oxygenation interval phase b the beginning and the end of sapropel deposition are dated at 957 0 81 kyr and 950 0 86 kyr respectively the duration of the interruption is estimated to 0 350 0 32 kyr the multiproxy approach highlights that deposition of sapropel 19 reflects a period of enhanced freshwater runoff induced by a wetter climate as a consequence of a more efficient fluvial erosion a higher terrigenous input mostly ascribable to a southern apennines source and an increased turbidity of surface waters accompanied most of sapropel deposition biotic and abiotic proxies document that different paleoenvironmental conditions occur through phases a c the beginning of phase a is characterized by warm on land paleoclimate as well as warm and oligotrophic surface water conditions during the upper part of phase a temperature starts decreasing and surface waters appear more productive this change probably represents the prelude to cooler and drier conditions characterizing phase b which displays a river supply reduction and an eolian input increase sahara dust during phase c the restored depleted oxygen environment at the bottom sediments is clearly coupled with the re establishment of humid conditions and increased river supply at the same time enhanced mixing of water column a cooler paleoclimate and increased productivity of surface waters are recorded the latter likely favored by the enhanced mixing of water column and also increased delivery of land derived nutrients the end of phase c is marked by a restored normal run off enhanced productivity in surface waters and low oxygen conditions at the bottom sediments persist slightly above phase c the overall results suggest that the onset of sapropel deposition is related to water stratification that caused low oxygen exchanges with the sea bottom although enhanced productivity characterizes most of the sapropel deposition it was not the primary factor triggering sapropel deposition

seismic exploration in complex terrains a processing experience in the southern apennines we discuss a data processing sequence adopted to reprocess a seismic line that crosses the italian southern apennines from the tyrrhenian sea to the adriatic margin and investigate both the overthrust and foreland areas we first determine the main causes of the very low s n ratio in the field data and then propose a processing sequence aimed at exploiting the signal content also making use of a priori geological knowledge of this area our work indicates a combination of causes for the very low quality of the seismic data these include length of the spread about 20 km that is unfavorable because of the rapid variation in the near surface geology tectonic complexity crooked line acquisition and the rough topography associated with outcropping rocks characterized by highly variable velocities based on the outcome of this data analysis we present a processing sequence driven by knowledge of the regional tectonic setting and by knowledge of the shallow subsurface geology the main effort is in remov

topography of the calabria subduction zone southern italy clues for the origin of mt etna 1 calabria represents an ideal site to analyze the topography of a subduction zone as it is located on top of a narrow active wadati benioff zone and shows evidence of rapid uplift we analyzed a pattern of surface deformation using elevation data with different filters and showed the existence of a long wavelength 100 km relatively positive topographic signal at the slab edges the elevation of mis 5 5 stage marine terraces supports this pattern although the record is incomplete and partly masked by the variable denudation rate we performed structural analyses along the major active or recently reactivated normal faults showing that the extensional direction varies along the calabrian arc and laterally switches from arc normal within the active portion of the slab to arc oblique or even arc parallel along the northern and southern slab edges this surface deformation pattern was compared with a recent high resolution p wave tomographic model showing that the high seismic velocity anomaly is continuous only within the active wadati benioff zone whereas the northern and southwestern sides are marked by low velocity anomalies suggesting that large scale topographic bulges volcanism and uplift could have been produced by mantle upwelling we present numerical simulations to visualize the three dimensional mantle circulation around a narrow retreating slab ideally similar to the one presently subducting beneath calabria we emphasize that mantle upwelling and surface deformation are expected at the edges of the slab where return flows may eventually drive decompression melting and the mount etna volcanism

migration and shortening rates in the northern apennines italy implications for seismic hazard abstract is compression across the northern apennine fold and thrust system italy still active to address this question we quantified the long term rates of migration and shortening of the system along with the measurement errors our approach integrates structural geology seismicity patterns and statistical treatment of tectonic activity based on recently published surface and subsurface data we found a migration rate of 8 85 0 61 mm y the inception age of individual fold structures follow closely this average rate indicating that the system has been migrating at a constant rate for the past 17 myr cumulative shortening of the system also increases linearly through time at 2 93 0 31 mm y the location of the youngest structures in the easternmost portion of the system coincides with a significant peak of seismic moment released by historical earthquakes we conclude that not only these easternmost thrusts are still active but also that they generate earthquakes keywords

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

reconciliation of late quaternary sea levels derived from coral terraces at huon peninsula with deep sea oxygen isotope records a major discrepancy between the late quaternary sea level changes derived from raised coral reef terraces at the huon peninsula in papua new guinea and from oxygen isotopes in deep sea cores is resolved the two methods agree closely from 120 ka to 80 ka and from 20 ka to 0 ka ka 1000 yr before present but between 70 and 30 ka the isotopic sea levels are 20 40 m lower than the huon peninsula sea levels derived in earlier studies new high precision u series age measurements and revised stratigraphic data for huon peninsula terraces aged between 30 and 70 ka now give similar sea levels to those based on deep sea oxygen isotope data planktonic and benthic 18o data using the sea level and deep sea isotopic data oxygen isotope ratios are calculated for the northern continental ice sheets through the last glacial cycle and are consistent with results from greenland ice cores the record of ice volume changes through the last glacial cycle now appears to be reasonably complete

the puglia uplift se italy an anomaly in the foreland of the apenninic subduction due to buckling of a thick continental lithosphere the apenninic foreland shows two distinct structural signatures comparing the central adriatic sea and the puglia region during the pliocene pleistocene the central adriatic underwent high subsidence rates due to the eastward rollback of the hinge of the west dipping apenninic subduction the puglia region and the bradanic foredeep are located southward along strike in the same foreland but in contrast with the central adriatic after pliocene early pleistocene subsidence they underwent uplift since the middle pleistocene the geometry and the kinematics of the frontal accretionary wedge and related foreland changed from that moment on between the two areas at the front of the central northern apennines off scraping and subsidence continued whereas the foredeep and foreland of the southern apennines were buckled those differences are interpreted as being due to the larger subduction hinge rollback rate since middle pleistocene of the central adriatic lithosphere 70 km thick with respect to the thicker puglia 110 km the different thicknesses of the continental crust and lithosphere were inherited from the mesozoic rifting that disrupted the adriatic plate the different thicknesses appear to have controlled the variable degree of flexure of the lithosphere and its asthenospheric penetration rate the tremiti e w alignment is the right lateral lithospheric transfer zone of those different tectonic regimes the consequent different dip of the subduction in the two sections steeper west of puglia could also explain the lower elevation of the southern apennines compared to their central northern sector

subduction kinematics and dynamic constraints the kinematics of subduction zones shows a variety of settings that can provide clues for dynamic understandings two reference frames are used here to describe the simple 2d kinematics of subduction zones in the first the upper plate is assumed fixed whereas in the second frame upper and lower plates move relative to the mantle relative to a fixed point in the upper plate u the transient subduction hinge h can converge diverge or be stationary similarly the lower plate l can converge diverge or be stationary the subduction rate vs is given by the velocity of the hinge h minus the velocity of the lower plate l vs vh vl the subduction rate 1 increases when h diverges and 2 decreases when h converges combining the different movements at least 14 kinematic settings can be distinguished along the subduction zones variable settings can coexist even along a single subduction zone as shown for the 5 different cases occurring along the apennines subduction zone apart from few exceptions the subduction hinge converges toward the upper plate more frequently along e or ne directed subduction zone whereas it mainly diverges from the upper plate along w directed subduction zones accompanying backarc extension before collision orogen growth occurs mostly at the expenses of the upper plate shortening along e ne directed subduction zones whereas the accretionary prism of w directed subduction zones increases at the expenses of the shallow layers of the lower plate the convergence shortening ratio is 1 along e or ne directed subduction zones whereas it is 1 along accretionary prisms of w directed subduction zones backarc spreading forms in two settings along the w directed subduction zones it is determined by the hinge divergence relative to the upper plate minus the volume of the accretionary prism or in case of scarce or no accretion minus the volume of the asthenospheric intrusion at the subduction hinge since the volume of the accretionary prism is proportional to the depth of the decollement plane the backarc rifting is inversely proportional to the depth of the decollement on the other hand along e or ne directed subduction zones few backarc basins form e g aegean andaman and can be explained by the velocity gradient within the hangingwall lithosphere separated into two plates when referring to the mantle the kinematics of subduction zones can be computed either in the deep or in the shallow hotspot reference frames the subduction hinge is mostly stationary being the slab anchored to the mantle along w directed subduction zones whereas it moves w or sw ward along e or ne directed subduction zones surprisingly along e or ne directed subduction zones the slab moves out of the mantle i e the slab slips relative to the mantle opposite to the subduction direction kinematically this subduction occurs because the upper plate overrides the lower plate pushing it down into the mantle as an example the hellenic slab moves out relative to the mantle i e sw ward opposite to its subduction direction both in the deep and shallow hotspot reference frames in the shallow hotspot reference frame upper and lower plates move westward relative to the mantle along all subduction zones this kinematic observation casts serious doubts on the slab negative buoyancy as the primary driving mechanism of subduction and plate motions w directed subduction zones rather provide about 2 3 times larger volumes of lithosphere re entering into the mantle and the slab is pushed down this opposite behavior is consistent with the down dip extension seismicity along e ne directed subduction zones and the frequent down dip compression along the w directed subduction zones subduction kinematics shows that plate velocity is not dictated by the rate of subduction along the w directed subduction zones the rate of subduction is rather controlled i by the hinge migration due to the slab interaction with the easterly trending horizontal mantle wind along the global tectonic mainstream ii by the far field plate velocities and iii by the value of negative buoyancy of the slab relative to the country mantle alternatively e ne nne directed subduction zones have rates of sinking chiefly determined i by the far field velocity of plates and ii by the value of negative buoyancy of the slab relative to the country mantle along this type of subduction the subduction hinge generally advances e ne ward toward the upper plate decreasing the subduction rate but it moves w sw ward relative to the mantle all this indicates that subduction zones have different origin as a function of their geographic polarity and the subduction process is more a passive feature rather than being the driving mechanism of plate motions a rotational component combined with mantle density and viscosity anisotropies seems more plausible for generating the global tuning in the asymmetry of subduction zones

stable isotope geochemistry of ground and surface waters associated with undisturbed massive sulfide deposits constraints on origin of waters and water rock reactions abstract stable isotopes h o c were determined for ground and surface waters collected from two relatively undisturbed massive sulfide deposits halfmile lake and restigouche in the bathurst mining camp bmc new brunswick canada additional waters from active and inactive mines in the bmc were also collected oxygen and hydrogen isotopes of surface and shallow groundwaters from both the halfmile lake and restigouche deposits are remarkably uniform 13 to 14 and 85 to 95 for 18ovsmow and 2hvsmow respectively these values are lighter than predicted for northern new brunswick and combined with elevated deuterium excess values suggest that recharge waters are dominated by winter precipitation recharged during spring melting deeper groundwaters from the restigouche deposit and from active and inactive mines have heavier 18ovsmow ratios up to 10 8 than shallow groundwaters suggesting recharge under warmer climate or mixing with shield type brines some of the co variation in cl concentrations and 18ovsmow ratios can be explained by mixing between saline and shallow recharge water end members carbon isotopic compositions of dissolved inorganic carbon dic are variable ranging from 15 to 5 13cvpdb for most ground and surface waters much of the variation in the carbon isotopes is consistent with closed system groundwater evolution involving soil zone co2 and fracture zone carbonate minerals calcite dolomite and siderite average 6 5 13cvpdb the dic of saline restigouche deposit groundwater is isotopically heavy 12 13cvpdb indicating carbon isotopic fractionation from methanogenesis via co2 reduction consistent with the lack of dissolved sulfate in these waters and the observation of ch4 degassing during sampling

regional deformation and offshore crustal local faulting as combined processes to explain uplift through time constrained by investigating differentially uplifted late quaternary palaeoshorelines the foreland hyblean plateau se sicily

permeability enhancements of borehole outburst cavitation in outburst prone coal seams abstract borehole outbursts eject coal power create cavities and relieve in situ stress while drilling cross measure boreholes into outburst coal seams for pre drainage this paper highlights the borehole outburst cavitation to enhance the permeability of coal for the first time borehole outburst is a mechanical behavior and the outburst trigger and development depend on the status of gas pressure gradient near the opening coal wall it was testified that the high pressure water with 10 15 mpa in pressure and 20 30 m3 h in flow was feasible to remove the failure coal near the opening wall and stimulate a new set of outbursts thus creating bigger cavities and better permeability enhancement furthermore an outburst control system was designed for borehole outburst cavitation the system contains an outburst stimulation subsystem a gas drainage subsystem and a separation subsystem thus ensuring the flow and the separation of outburst ejections within a relatively closed environment the outburst cavity reconstitutes the in situ stress and permeability of the surrounding coal mass leading to a failure zone a plastic zone and a visco elastic zone the failure zone and the plastic zone due to borehole outburst cavitation are both effective in permeability enhancement finally a field test in the no 10 coal seam at the luling mine proved that the sufficient permeability enhancement scope is approximately twelve times of the cavity radius the permeability enhancement promotes the increase of borehole distance from 5 m to 12 m thus reducing 78 7 of boreholes in number for the pre drainage of the no 10 coal seam

hydrochemical processes in a shallow coal seam gas aquifer and its overlying stream alluvial system implications for recharge and inter aquifer connectivity abstract in areas of potential coal seam gas csg development understanding interactions between coal bearing strata and adjacent aquifers and streams is of highest importance particularly where csg formations occur at shallow depth this study tests a combination of hydrochemical and isotopic tracers to investigate the transient nature of hydrochemical processes inter aquifer mixing and recharge in a catchment where the coal bearing aquifer is in direct contact with the alluvial aquifer and surface drainage network a strong connection was observed between the main stream and underlying alluvium marked by a similar evolution from fresh ca mg hco3 waters in the headwaters towards brackish ca na cl composition near the outlet of the catchment driven by evaporation and transpiration in the coal bearing aquifer by contrast considerable site to site variations were observed although waters generally had a na hco3 cl facies and high residual alkalinity values increased salinity was controlled by several coexisting processes including transpiration by plants mineral weathering and possibly degradation of coal organic matter longer residence times and relatively enriched carbon isotopic signatures of the downstream alluvial waters were suggestive of potential interactions with the shallow coal bearing aquifer the examination of temporal variations in deuterium excess enabled detection of rapid recharge of the coal bearing aquifer through highly fractured igneous rocks particularly at the catchment margins most waters collected from the coal bearing aquifer also showed an enhanced influence of weathering during the wet season which was likely triggered by the water rock interaction with fresh recharge waters an increase in both residual alkalinity and carbon isotopic ratios at two locations indicated inter aquifer mixing between alluvium and bedrock during the wet season the results of this study emphasise the need for conducting baseline hydrochemical surveys prior to csg development in order to describe the transient nature of recharge and inter aquifer mixing processes

uplift and active tectonics of southern albania inferred from incision of alluvial terraces abstract in albania the osum and vjoje rivers cross the active graben system and the active frontal thrust system of the albanides the effects of climatic and geodynamic forcing on the development of these two rivers were investigated by the means of field mapping topographic surveying and absolute exposure age dating we established the chronology of terraces abandonment from the compilation of new dating 14c and in situ produced 10be and previously published data we identified nine fluvial terraces units developed since marine isotope stage 6 up to historic times from this reconstituted history we quantified the vertical uplift on a time scale shorter than the glacial climatic cycle regional bulging produces an overall increase of the incision rate from the west to the east that reaches a maximum value of 2 8 m ka in the hinterland local pulses of incision are generated by activation of normal faults the most active faults have a sw ne trend and a vertical slip rate ranging from 1 8 to 2 2 m ka this study outlines the geodynamic control in the development of rivers flowing through the albanides on the scale of 103 105ka

pleistocene raised marine terraces of the spanish mediterranean and atlantic coasts records of coastal uplift sea level highstands and climate changes detailed geological mapping morphostratigraphic palaeontological and geochronological uranium series analyses were undertaken on the raised marine terraces and interbedded terrestrial deposits along the spanish peninsular and insular atlantic and mediterranean coasts several sets of pleistocene shallow marine to coastal deposits exposed in a staircase arrangement are interpreted as being emplaced during sea level highstands coeval with interglacials or interstadials correlating with marine oxygen isotopic stages ois 5a 5c 5e 7 9 11 and older up to three highstands have been identified in deposits formed during ois 5e close to the end of ois 5e there is a record of sudden changes in sea surface conditions and climate marked by the disappearance of a major proportion of the warm senegalese fauna switches from oolitic to non oolitic facies and accumulation of boulder beaches dating of the coral cladocora caespitosa found in a layer that also contains strombus bubonius confirms the occurrence of warm fauna in the mediterranean basin during ois 7 as previously suggested by hillaire marcel et al 1986 goy et al 1986a b zazo and goy 1989 also the occurrence of warm faunas in deposits corresponding to an older interglacial probably ois 9 or 11 in the balearic islands suggests similar oceanographic conditions sea surface temperature assuming constant salinity during the last interglacial and at least two interglacials of the middle pleistocene in the western mediterranean a 2002 elsevier science b v all rights reserved

foraminiferal record and environmental changes during the deposition of the early middle pleistocene sapropels in southern italy a foraminiferal investigation documents the palaeoenvironmental changes across the sapropel units associated with insolation cycles 90 and 86 in the early middle pleistocene im fosso 5 agosto section basilicata southern italy three benthic foraminiferal fossil associations associations a b and c identified by performing hierarchical cluster analysis on the quantitative data can be considered diagnostic of the palaeoenvironmental conditions before during and after the sapropel intervals they indicate a gradual decrease of bottom water oxygenation prior to the onset of sapropel deposition and a rapid return to stable environmental conditions at the end of the sapropel events the constant presence of benthic foraminifera throughout the sapropels implies that the bottom environment was not totally anoxic the high resolution distributional pattern of planktonic and benthic foraminifera within the sapropel associated with i cycle 90 documents a surface water cooling with consequent rapid re oxygenation of bottom waters that subdivides this interval in two phases both of them are characterized by an early subphase with warm climate conditions a decrease of salinity in surficial water layers and dominated by the low oxygen tolerant benthic species globobulimina affinis the late subphase shows thermal stratification during summer and a relatively deep and oxygenated mixed layer during winter in this subphase the contemporaneous replacement of g affinis the bless opportunistic but more resistant to low oxygen conditionsq species with bolivina alata bolivina dilatata and brizalina spathulata the bless resistant to low oxygen conditionsq species indicates the relative oxygen improvement in sediment pore water the frequent changes detected in the sapropel associated faunal composition underline the unstable nature of bottom water oxygen content d 2004 elsevier b v all rights reserved

surface and subsurface of the metaponto coastal plain gulf of taranto southern italy present day vs lgm landscape abstract the metaponto coastal plain mcp in southern italy stretches 60 km long and 5 km wide along the gulf of taranto in the ionian sea and is presently subject to strong anthropogenic pressure a multidisciplinary study reviewed the geomorphology lithostratigraphy and sedimentology of the mcp and its subsurface incorporating both borehole and radiocarbon dating information in the review this paper focuses on comparisons and differences between present day and buried late pleistocene landscapes lgm and mis 3 the modern coastal plain is the top of a late holocene coastal wedge prograding on a very narrow shelf that is connected to a deep basin the ionian sea by a steep slope this scenery likely resembles those produced during earlier late quaternary relative highstands and is in marked contrast with that produced during the last sea level fall and lowstand and buried in the mcp subsurface the last scenery corresponds to the lgm landscape where river valleys deeply dissected a previous highstand coastal wedge mis 3 whose remnants represented interfluve areas thanks to resonance properties of the subsurface this buried landscape was obtained in a 3d visualization highlighting location and shape of incised valleys and interfluve areas during the lgm

geophysical and petrological modelling of the structure and composition of the crust and upper mantle in complex geodynamic settings the tyrrhenian sea and surroundings abstract information on the physical and chemical properties of the lithosphere asthenosphere system las can be obtained by geophysical investigation and by studies of petrology geochemistry of magmatic rocks and entrained xenoliths integration of petrological and geophysical studies is particularly useful in geodynamically complex areas characterised by abundant and compositionally variable young magmatism such as in the tyrrhenian sea and surroundings a thin crust less than 10 km overlying a soft mantle where partial melting can reach about 10 is observed for magnaghi vavilov and marsili which belong to the central tyrrhenian sea backarc volcanism where subalkaline rocks dominate similar characteristics are seen for the uppermost crust of ischia a crust about 20 km thick is observed for the majority of the continental volcanoes including amiata vulsini roccamonfina phlegraean fields vesuvius vulture stromboli vulcano lipari etna and ustica a thicker crust is present at albani about 25 km and at cimino vico sabatini about 30 km the structure of the upper mantle in contrast shows striking differences among various volcanic provinces volcanoes of the roman region vulsini sabatini alban hills sit over an upper mantle characterised by vs mostly ranging from about 4 2 to 4 4 km s at the alban hills however slightly lower vs values of about 4 1 km s are detected between 60 and 120 km of depth this parallels the similar and rather homogeneous compositional features of the roman volcanoes whereas the lower vs values detected at the alban hills may reflect the occurrence of small amounts of melts within the mantle in agreement with the younger age of this volcano the axial zone of the apennines where ultrapotassic kamafugitic volcanoes are present has a mantle structure with high velocity lid vs 4 5 km s occurring at the base of a 40 km thick crust beneath the campanian volcanoes of vesuvius and phlegraean fields the mantle structure shows a rigid body dipping westward a feature that continues southward up to the eastern aeolian arc in contrast at ischia the upper mantle contains a shallow low velocity layer vs 3 5 4 0 km s just beneath a thin but complex crust the western aeolian arc and ustica sit over an upper mantle with vs 4 2 4 4 km s although a rigid layer vs 4 55 km s from about 80 to 150 km occurs beneath the western aeolian arc in sardinia no significant differences in the las structure are detected from north to south the petrological geochemical signatures of italian volcanoes show strong variations that allow us to distinguish several magmatic provinces these often coincide with mantle sectors identified by vs tomography for instance the roman volcanoes show remarkable similar petrological and geochemical characteristics mirroring similar structure of the las the structure and geochemical isotopic composition of the upper mantle change significantly when we move to the stromboli campanian volcanoes the geochemical signatures of ischia and procida volcanoes are similar to other campanian centres but sr pb isotopic ratios are lower marking a transition to the backarc mantle of the central tyrrhenian sea the structural variations from stromboli to the central vulcano and lipari and western aeolian arc are accompanied by strong variations of geochemical signatures such as a decrease of sr isotope ratios and an increase of nd pb isotope and lile hfse ratios the dominance of mafic subalkaline magmatism in the tyrrhenian sea basin denotes large degrees of partial melting well in agreement with the soft characteristics of the uppermost mantle in this area in contrast striking isotopic differences of plio quaternary volcanic rocks from southern to northern sardinia does not find a match in the las geophysical characteristics the combination of petrological and geophysical constraints allows us to propose a 3d schematic geodynamic model of the tyrrhenian basin and bordering volcanic areas including the subduction of the ionian adria lithosphere in the southern tyrrhenian sea and to place constraints on the geodynamic evolution of the whole region

interpreting quaternary uplift rates at the mendocino triple junction northern california from uplifted marine terraces analysis of the altitudinal spacing of 14 flights of marine terraces indicates a spatial pattern of varying uplift rates that agrees with that determined from previously dated terraces for the past 3 81 ka and temporal changes in uplift rates from 1 m ka to 3 5 m ka that may reflect response to changes in tectonic regime during passage of the mendocino triple junction mtj a possible mechanism for regional uplift is growth of a slab window south of the mtj the region of most rapid uplift is 25 43 km south of the mtj immediately south of the northern boundary of the slab window the coastline is tilted upward to the south in the region directly above the southern edge of the subducted gorda plate at point delgada 55 km south of the present mtj where the northern edge of the slab window passes approximately 300 ka uplift rates have been 1 2 m ka for at least 330 ka more than 1 4 m y after passage of the southern edge of the subducted slab at the mendocino coast uplift rates have been less than 0 4 m ka for at least 330 ka

a kinematic model for the plio quaternary evolution of the tyrrhenian apenninic system implications for rifting processes and volcanism abstract during the frontal accretion due to the late miocene quaternary thrusting the interior of the apenninic chain underwent large scale extension which produced the opening of the tyrrhenian oceanic basin a back arc basin in respect to the late cenozoic apenninic chain and the onset of the quaternary volcanic activity in the campanian plain and more generally in the tyrrhenian area to outline the space time distribution and the geotectonic setting of the tyrrhenian volcanics we approached the problem from a kinematic point of view a synthesis of the available geological and geophysical data leads us to suggest that the progressive migration of the apenninic arcs is responsible for the extension phenomena which took place during the last 5 ma at first the extension resulted from the kinematic interaction between the northern apenninic arc and the southern apenninic arc during the late pliocene then from the early pleistocene the extension was controlled by the se migration of the southern arc only and therefore it can be regarded as part of the general southern tyrrhenian extension phenomenon due to the intense thinning the isotherms migrated upward very rapidly within the toscana latium and campania lithosphere where the melting point was reached giving rise to the onset of volcanic activity at the end of the early pleistocene

piggyback basin development and thrust belt evolution structural and palaeostress analyses of plio quaternary basins in the southern apennines abstract in southern italy structural analysis of the intramontane pliocene quaternary terrigenous basins of sant arcangelo and ofanto shows that they are piggyback basins the recent uplift of the southern apennines provides good conditions for carrying out detailed studies of palaeostresses in relation to structure and sediment accumulation in such piggyback basins we demonstrate that in the pleistocene sant arcangelo marine basin a single n70 compression induced a complex pattern of folds and strike slip faults in contrast the older pliocene ofanto basin reveals a polyphase history characterized by successive tilts and palaeostresses according to different compressions in both basins compressional stresses are syn depositional the geometry of the sedimentary infill of these basins provides information on the thrusting activity in terms of location geometry and age we point out that in addition to sedimentary and structural studies including interpretation of seismic reflection data palaeostress analyses provide a valuable tool for deciphering development and evolution of compressional basins in a fold and thrust belt

stratigraphical and chronological correlations between monte vulture volcanics and sedimentary deposits of the venosa basin abstract a new chronostratigraphic reconstruction of vulture activity was used to correlate its volcanic products and relevant lacustrine fluviolacustrine beds deposited in the nearby basins of venosa melfi and atella the acquatraversa erosional phase precedes the beginning of volcanic activity the flaminia erosional phase occurred during the period of volcanic quiescence before the buildup of the vulture san michele stratovolcano reworked mammal remains are found in the upper bed related to the nomentana erosional phase this erosional phase took place after the main period of volcanic activity when the stratovolcano was fully constructed

deep structure of the campanian lucanian arc southern apennine italy abstract recent exploration activities and successful discovery of large oil fields in the upper val d agri area southern apennine italy have encouraged the collection of large quantities of geological and geophysical data and their integration into comprehensive geological models here we present a series of structural profiles based on several hundred kilometres of seismic lines two and three dimensional and the results of many deep wells the best seismic lines have been extensively reprocessed and also tied to magnetotelluric data geological interpretations of those lines have been interactively tested and verified by gravity and magnetic modelling and structural balancing the wells and seismic data demonstrate that the fundamental tracts of the deep architecture of the orogen as it appears today were developed only at the end of the late pliocene the final closure of the ensialic shear zone responsible for the subduction of at least 150 km of continental lithosphere originally underlying the lagonegro basin can be dated as early pliocene the involvement of the inner apulian platform in the core of the belt and the activation of a new and more external left lateral oblique ensialic shear zone can be constrained to the late pliocene pleistocene the seismic profiles clearly show the underthrusting of the outer apulian platform unit beneath the inner apulian platform unit the thick skinned character of the plio pleistocene contractional structures is evident from the structural profiles this geometry is constrained by gravity magnetic data and structural considerations according to the relatively steep angle of dip about 10 of the apulian foreland beneath the chain the structural profiles depict the general architecture of the campanian lucanian arc the apennine platform and lagonegro unit are largely allochthonous and a part of the lagonegro basement could be buried below the apennine platform sole thrust the neogene plastic successions of the apennine platform and lagonegro basin were detached and now outcrop in the bradanic foredeep the inner apulian platform constitutes a huge thrust sheet structured as a wide antiform in the core of the belt its regional culmination roughly corresponds to the val d agri area extensional and transtensional structures cross cut the pre existing compressional structures as shown by the quaternary valleys of vallo di diano and val d agri the profiles shown also highlight the existing contrast between the deep structures in the core of the belt and the tectonic style of the lagonegro liguride and sicilide units these units were in fact subjected to brittle ductile deformation under metamorphic part of liguridi units and deep diagenetic to anchizonal conditions lagonegro units and were affected by a general overthrust shear directed towards the ne the inner apulian platform was on the contrary involved in the thrust belt together with its basement whereas the outer apulian platform affected by a subduction underwent a regional bending with associated normal faulting

geological controls on the geometry of incised valley fills insights from a global dataset of late quaternary examples incised valleys that develop due to relative sea level change are common features of continental shelves and coastal plains assessment of the factors that control the geometry of incised valley fills has hitherto largely relied on conceptual experimental or numerical models else has been grounded on case studies of individual depositional systems here a database driven statistical analysis of 151 late quaternary incised valley fills has been performed the aim being to investigate the geological controls on their geometry results of this analysis have been interpreted with consideration of the role of different processes in determining the geometry of incised valley fills through their effect on the degree and rate of river incision and on river size and mobility the studied incised valley fills developed along active margins are thicker and wider on average than those along passive margins suggesting that tectonic setting exerts a control on the geometry of incised valley fills likely through effects on relative sea level change and river behaviour and in relation to distinct characteristics of basin physiography water discharge and modes of sediment delivery valley fill geometry is positively correlated with the associated drainage basin size confirming the dominant role of water discharge climate is also inferred to exert a potential control on valley fill dimensions possibly through modulations of temperature peak precipitation vegetation and permafrost which would in turn affect water discharge rates of sediment supply and valley margin stability shelves with slope breaks that are currently deeper than 120 m contain incised valley fills that are thicker and wider on average than those hosted on shelves with breaks shallower than 120 m no correlation exists between valley fill thickness and present day coastal prism convexity which is measured as the difference in gradient between lower coastal plains and inner shelves these findings challenge some concepts embedded in sequence stratigraphic thinking and have significant implications for analysis and improved understanding of source to sink sediment route ways and for attempting predictions of the occurrence and characteristics of hydrocarbon reservoirs