pleistocene raised marine deposits of the cap bon peninsula n e tunisia records of sea level highstands climatic changes and coastal uplift abstract morphostratigraphic and sedimentological studies were undertaken in the cap bon peninsula north eastern tunisia these studies have identified a series of middle to late pleistocene age marine deposits discontinuously cropping out on three raised platforms pf i pf ii and pf iii these stepped marine platforms terraces were related to the interplay between pleistocene sea level changes and progressive uplift movement during quaternary period we present here a description of facies organization and stratigraphic characteristics of the platform deposits and their relation with eustatic and climatic variations all the marine platforms unconformably overlie a mio pliocene and quaternary slope succession the sedimentary sequences represented by mixed carbonate and siliciclastic bodies are related to the succession of highstand shorelines and contrasting climate conditions the intercalated soils and calcretization occurred during episodes of relative sea level fall the oldest platforms pf i and pf ii found at an elevation of about 100 m and 60 m respectively have so far no equivalent in the northern in the eastern or in the southern coasts of tunisia they are correspondingly attributed to mis 11 13 and mis 9 11 the youngest and lowest platform pf iii attains an altitude of 40 m and shows three high frequency cycles of sea level rise and fall probably associated with marine isotope stage mis 5e and mis 7

climatic controls on late pleistocene alluvial fans cyprus alluvial fans are commonly associated with tectonically active mountain ranges and tectonism is frequently held responsible for abrupt coarsening and cyclical sedimentation of alluvial fan sequences whilst it is accepted that tectonism provides the opportunity for alluvial fan development through the creation of topography increasing gradients of fluvial systems supplying sediments and creating accommodation for the storage of sediment flux the role of climate in fan development is frequently neglected the hypothesis that climatically controlled events can produce recognisable sedimentary signatures in alluvial fan deposits is tested in the active supra subduction zone setting of the late pleistocene of southern cyprus this study demonstrates through architectural analysis and the reconstruction of palaeoflood hydrology a recorded pattern of increasing and decreasing palaeoflow dynamics with switches from a wetter to drier mode clearly exhibited by changes in the sedimentology of the fan at the present day cyprus has a semi arid climate and is influenced by a strongly seasonal rainfall pattern largely restricted to the winter months plus rare occurrences of summer cyclones however at precession minima increased activity of western mediterranean depressions produces wetter summers using inference we propose that longer term increases in rainfall increased river discharge as recorded in the fan palaeoflood hydrology and occurred at minima in the precession these periods correlate with the deposition of conglomeratic channels and open framework gravels drier periods are exhibited by sandier braided fluvial deposits shorter term or seasonal change is recorded in the form of 2nd and 3rd low order bounding surfaces this increased activity of mediterranean summer depressions increased precipitation to the wider levantine area and was coincident with increased intensity of the north african and indian ocean sw monsoons the resultant increase in river discharges at precession minima from both the nile and the wider levant resulted in the formation of sapropels in the eastern mediterranean and is recorded as wet periods in speleothem deposits in the soreq and peqiin caves of israel the predominant control of sedimentation on the late pleistocene alluvial fans of southern cyprus was climate

late pleistocene coastal evolution of san giovanni di sinis west sardinia western mediterranean abstract the upper pleistocene succession of coastal deposits outcropping at san giovanni di sinis west sardinia has been studied since the 1960s however the absence of consistent radiometric ages has allowed the production of competing stratigraphic subdivisions of these deposits with different isotopic stage ois mis attributions the succession is composed of sandy to gravelly shallow marine coastal aeolian and alluvial fan plain deposits facies analysis and log correlations show the presence of three unconformities t1 t2 t3 always overlain by shallow marine deposits cutting through the substrate alluvial fan or aeolian sediments we have collected three samples for optically stimulated luminescence osl dating at the top of each shallow marine deposit the succession is composed of four unconformity bounded units u1 u2 u3 u4 and the new osl dates indicate the presence of three different sea level highstands the first unit u1 which is composed of shallow marine to aeolian deposits and overlies transgressive surface t1 is related to a marine transgression during ois 7 186 13 ky unit 2 is composed of continental deposits and formed during ois 6 unit 3 represents ois 5 and overlies a transgressive surface t2 more precisely subunit u3a is related to ois 5e 120 10 ky eu tyrrhenian or eemian sensu strictu and is characterized by shallow marine to aeolian deposits developed during both transgressive and highstand phases the following bay deposits of subunit 3b are associated with ois 5c 100 5 ky and record a second transgressive event t3 and highstand phase occurred during the neo tyrrhenian the succession of san giovanni di sinis ends with continental deposits of unit 4 associated to a sea level fall that took place at the beginning of the last glacial phase ois 4

late pleistocene carbonate aeolianites on mallorca western mediterranean a luminescence chronology abstract coastal outcrops of upper pleistocene deposits in north eastern mallorca balearic islands spain have been examined and a chronological framework established using optically stimulated luminescence osl dating the outcrops record a complex interaction between aeolian colluvial and alluvial fan deposition that result in a variable stratigraphical architecture dating and facies analysis make it possible to identify four aeolian activity episodes during mis 5c b 4 and 3 and also add to the understanding of the environmental history of north eastern mallorca over the last 100 ka the new data suggest enhanced aeolian transport and dune formation during cold climatic intervals when sea level was low sediment supply exposed marine carbonate sediment was high winter windiness was high and vegetation on coastal plains at a minimum

the early pleistocene development of the gediz river western turkey an uplift driven climate controlled system this paper reports the latest details from an on going investigation of the early pleistocene buried river terrace sequence of the gediz river 40 km upstream of the alasehir graben in the kula volcanic province western turkey using clast lithology to characterise sediment provenance we demonstrate that the buried early pleistocene terrace sequence of the palaeo gediz is overlain by the deposits of two carbonate rich northerly derived tributary systems the surface form of these carbonate rich deposits suggests deposition on alluvial fans an interpretation supported by limited palaeocurrent data and upwards coarsening sequences suggesting fan progradation it is argued that the formation and preservation of the palaeo gediz terrace sequence is intimately related to fan deposition fan head entrenchment and fan progradation terrace formation is the result of incision in the main gediz valley a response to long term uplift during periods of lower sediment supply under low sediment supply conditions inferred fan head entrenchment is associated with fan toe progradation this progradation would have led to the burial of the newly formed terrace of the gediz subsequent higher sediment supply conditions would have led to renewed fan deposition the direct coupling of the fan system with the main gediz river during these periods would also result in deposition within the trunk river the primary control of sediment supply is considered here to reflect changing vegetation cover a function of changing quaternary climates these inferred controls suggest that the gediz early pleistocene terrace sequence is an uplift driven climate controlled system

controls on the erosion of cenozoic asia and the flux of clastic sediment to the ocean rates of continental erosion may be reconstructed from variations in the rate of accumulation of clastic sediment most of which lies offshore global rates of marine sedimentation are usually considered to have reached a maximum after 3 4 ma driven by enhanced erosion in a variable glacial interglacial climate however a new compilation of seismic data from the marginal seas of asia now shows that only the red river reached its historic peak after 4 ma sediment flux from asia first peaked in the early middle miocene 24 11 ma well before the initiation of a glacial climate indicating that rock uplift and especially precipitation are the key controls on erosion at least over long periods of geologic time reconstructions of weathering in east asia show that faster erosion correlates with more humid warm climates in the early middle miocene changing to less erosive drier climates after 14 ma when antarctic glaciation begins average rates of sedimentation on most east asian continental margins since 1 8 ma are 5 6 times less than the modern fluvial flux implying that the flux to the oceans varies sharply on short timescales and is not always buffered over timescales of 10 4 yr by storage in flood plains

late pleistocene paleoclimates and sea level change in the mediterranean as inferred from stable isotope and u series studies of overgrowths on speleothems mallorca spain abstract phreatic overgrowths on speleothems form at the surface of brackish pools which are present in many coastal caves of mallorca spain unlike common vadose speleothems formed in subaerial environments their occurrence directly identifies the height of the sea level at the time of the carbonate deposition because such pools are physically connected with the sea these deposits from the late pleistocene have recorded the same global variations in oxygen isotopes as planktonic and benthonic foraminifera corals and cave deposits a number of phreatic overgrowths on speleothems have been dated using the th u method in order to determine the position of the sea level during late quaternary the same samples as well as some subaerial speleothems have been analysed for 18 o 16 o and 13 c 12 c ratios the former samples allow the analysis of variations in sea water component in the brackish pools associated with glacio eustatic mediterranean fluctuations and the latter permit inferences concerning past continental climate changes some high sea stands have been recognized in correspondence with oxygen isotope stages ois 9 or older 7 5e 5c and 5a phreatic overgrowths on speleothems have also been formed during a colder phase ois 4 demonstrating that also in that period there were environmental conditions favourable for this kind of carbonate precipitation vadose crystallizations have recorded a cold period at 36 ka corresponding with the end of ois 3

the timing of quaternary calcrete development in semi arid southeast spain investigating the role of climate on calcrete genesis quaternary aged calcrete horizons are common weathering products in arid and semi arid regions it is however unclear how calcrete forming processes respond to the major oscillations in climate that occur over the quaternary period this paper presents a u series based calcrete age database from the sorbas basin southeast spain the study constructs an age frequency distribution of these ages which is consequently compared to a range of palaeoenvironmental records from the mediterranean the age distribution presented here suggests that the formation of pedogenic calcrete horizons in the sorbas basin primarily occurs during warm isotope stages mis 1 and 5 with very few calcrete ages occurring during cold glacial stadial stages mis 2 3 and 4 it is suggested that this is a function of the environments that existed during warm isotope stages being more conducive to calcrete development than those that existed during cold climate episodes in a semi arid region such as the sorbas basin it is likely that increased aridity during glacial stages coupled with reduced vegetation and accelerated landscape instability was crucial in reducing rates of calcrete formation in a semi arid region such as southeast spain calcrete formation during the quaternary therefore oscillates with climate change but is primarily a warm episode phenomenon it is suggested that further studies are required to see how calcrete genesis responds to environmental change in more humid parts of the mediterranean

late pleistocene and holocene uplift history of cyprus implications for active tectonics along the southern margin of the anatolian microplate the nature of the southern margin of the anatolian microplate during the neogene is complex controversial and fundamental in understanding active plate margin tectonics and natural hazards in the eastern mediterranean region our investigation provides new insights into the late pleistocene uplift history of cyprus and the troodos ophiolite we provide isotopic 14 c and radiogenic luminescence dates of outcropping marine sediments in eastern cyprus that identify periods of deposition during marine isotope stages mis 3 4 5 and 6 past sea levels indicated by these deposits are c 95 25 m higher in elevation than estimates of worldwide eustatic sea level an uplift rate of c 1 8 mm year and possibly as much as c 4 1 mm year in the past c 26 40 ka is indicated holocene marine deposits also occur at elevations higher than those expected for past sl and suggest uplift rates of c 1 2 2 1 mm year mis 3 marine deposits that crop out in southern and western cyprus indicate uniform island wide uplift we propose a model of tectonic wedging at a plate bounding restraining bend as a mechanism for late pleistocene to holocene uplift of cyprus uplift is accommodated by deformation and seismicity along the margins of the troodos ophiolite and re activation of its low angle basal shear zone

sequence stratigraphy of miocene pliocene carbonate siliciclastic shelf deposits in the eastern mediterranean margin israel effects of eustasy and tectonics abstract mio pliocene marine sediments comprise a discontinuous succession of carbonates and mixed carbonate siliciclastics on the neogene shelf which coincides with the judean foothills area on the slope present mediterranean coastal plain the succession forms a wedge up to 1500 m thick of mostly fine grained siliciclastics the facies and architecture of the succession were influenced both by sea level fluctuation and by the geodynamic change from thermally subsiding passive margins of the arabo african plate to a complex pattern of vertical movements that were associated with the breakup of the plate along the red sea rift and dead sea transform and the convergence of the african arabian and eurasian plates the miocene eustatic succession is highly interrupted by vertical uplift tectonics while the pliocene eustatic succession is well represented despite the limited subsidence rates during most of the early and middle miocene the shelf was tectonically uplifted above sea level except for a short period of flooding in early middle miocene times n8 n9 when sea level rise outstripped the uplift trend and a carbonate platform formed the combination of tectonic uplift and sea level fall prior to late miocene times about 11 m y ago resulted in the incision of a deep beer sheva canyon about 280 m below the shelf plane late miocene sandy marlstones of the bet eshel cycle filled the beer sheva canyon and spilled over it they display a shallowing upward trend resulting in progradational clinoform stacking of the highstand systems tract and channelled debris flows of the forced regression systems tract the messinian desiccation event left the shelf emerged while depositing evaporites on the slope and in the basin the degree of erosion during the messinian was relatively minor because of arid conditions and limited runoff the pliocene shelf shows a very low subsidence rate and compared to the miocene succession is less affected by vertical uplifts the pliocene deposits are divided into six sequences their relative onlap curve largely corresponds to the sequence stratigraphic scheme in sicily and the gulf of mexico the two lowermost sequences i and ii are composed of two sandy units the lower forms an incised valley fill of shoreface deposits in the beer sheva area and offshore sand deposits in distal shelf areas besor although largely eroded sequences i and ii display maximum coastal onlap of all pliocene cycles in the beer sheva canyon area sequence iii consists of mixed carbonate siliciclastic grainstones of shoreface foreshore deposits in the proximal area and lower shoreface deposits in more distal areas sequences iv and v may be considered as a single 3rd order cycle where iv represents regressive lowstand shale and sand deposits and v represents prograding highstand sandy grainstone deposits sequence vi consists of marginal marine to coastal plain marlstones and sands deposits and is largely truncated by the ahuzam conglomerate representing a major uplift phase of latest pliocene to early pleistocene age and marking the permanent emergence of the shelf

late quaternary marine terraces in the mediterranean coastal area of syria geochronology and neotectonics abstract in order to provide new data on the neotectonics and geodynamic properties of western syria studies of marine terraces have been carried out the most attention was paid to the lower terraces in the range of 3 5 to 30 35 m above sea level because they have more complete distributions along the shore the lower terraces were examined along the coastal area from tartus to latakia and along the carbonate cliff on arwad island seven 230 th u dates for these terraces are in the range of 85 130 ka suggesting the age interval of the last interglacial mis 5 new dates on the lower terraces provide a basis for stratigraphical and geomorphological interpretation as well as neotectonic reconstruction according to the geomorphological data and lithological composition of those terraces two main uplifted blocks can be established one coincides with the latakia block and another corresponds to the western margin of the banias volcanic plateau these blocks are divided by a subsided structure corresponding to the nahr el kebir graben the amplitude of neotectonic uplifting in the latakia and banias blocks reaches 15 20 m for the late pleistocene

timing and hydrological conditions of sapropel events in the eastern mediterranean as evident from speleothems soreq cave israel this paper explores the connection between the timing of sapropel events in the eastern mediterranean sea and the time of low 18o events in speleothems of the soreq cave israel a new well dated 18o and 13c profile of the soreq cave speleothems for the last 140 kyr reveals five prominent low 18o events dated at 124 to 119 kyr with the main peak at 122 kyr event v 108 to 100 kyr with peaks at 107 and 102 kyr event iv 85 to 79 kyr with peak at 80 kyr event iii 55 to 52 kyr with a peak at 54 kyr event ii and 8 5 to 7 kyr with peaks at 8 5 and 7 kyr event i these events are characteristic of period of enhanced rainfall in the eastern mediterranean area particularly so for events v and i where the marked decrease in 18o and the correspondingly marked increase in 13c indicate very wet conditions the chronology of the low 18o events v iv iii and i match the ages estimated for the formation of sapropels s5 s4 s3 and s1 which are also associated with high hydrological activity thus it is suggested that the low 18o events in the soreq cave speleothems constrain the maximum duration of the sapropel formation pollen data from the sapropel layers and the isotopic pattern of the speleothems indicate that sapropels s5 and s1 were deposited during very wet periods when there were major decrease in the sea surface salinity coupled with frost free winters and drought free summers sapropels s4 and s3 were formed during periods of increased precipitation but ones in which the general climate was mediterranean semi arid

middle pleistocene magnetostratigraphy and susceptibility stratigraphy data from a carbonate aeolian system mallorca western mediterranean abstract this study shows that successions of pleistocene carbonate aeolian deposits can be placed successfully in a geochronologic framework using magnetostratigraphic and susceptibility stratigraphic analysis supplemented by luminescence dating studies of wave cut platforms and biostratigraphic evidence the investigated aeolian system covers a significant part of southernmost mallorca and is exposed in impressive coastal cliff sections at the study site at els bancals the aeolian system has a maximum thickness of 16 m and is composed of alternating dark red colluvial deposits and greyish red aeolian dune and sand sheet deposits forming seven cyclostratigraphic units each cyclostratigraphic unit represents landscape stabilisation colluviation and soil formation followed by dunefield development when marine carbonate sand was transported far inland by westerly or north westerly winds the aeolian system is located on top of a wave cut marine platform 12 14 m a s l this platform probably formed during a sea level highstand in marine isotope stage mis 11 427 364 ka and renewed marine activity probably later in mis 11 is indicated by the formation of beach deposits two sections at els bancals were sampled for a paleomagnetic study additional samples were taken to detect variations in magnetic susceptibility ms the characteristic remanent magnetisation has been recovered for the most part of the succession in spite of diagenetic overprinting there is evidence for two probably three reversal polarity excursions possible connected to the levantine cr1 and cr0 biwa iii episodes if this correlation is correct the sampled succession represents a time interval in the middle pleistocene between ca 410 and ca 260 ka this age estimate is supported by the ms study and by luminescence dates of 333 70 ka aeolianite from lower part of the succession and 275 23 ka aeolianite from the top of the succession the nature of the succession suggests deposition during alternating warm and moist colluvial deposition soil formation and cold dry and windy conditions dunefield formation the susceptibility signal can be correlated with the insolation signal at 65 n suggesting that environmental variation on mallorca was linked to orbitally forced climate change and it seems that aeolian activity and dunefield formation were linked to glacial or stadial periods

major controls on architecture sequence stratigraphy and paleosols of middle pleistocene continental sediments qc unit eastern central italy abstract middle pleistocene continental sediments in central italy qc unit record the oldest fluvial accumulation along the uplifting margin of the peri adriatic basin the architecture of the sediment body can be divided into two unconformity bounded fining upward cycles interpreted as genetically related depositional sequences these sequences highlight the systematic adjustment of the fluvial system to changes in the ratio between accommodation space and sediment supply a s ratio and from base to top comprise the following surfaces and stratal components i a regionally correlative sequence boundary resulting from an a s ratio 0 ii a low accommodation systems tract characterized by conglomerate rich amalgamated channel fills and recording an a s ratio 1 and v a mature red argillic paleosol to constrain the climatic signal for paleosols formation the two sequence capping mature paleosols have been investigated the results of these studies suggest that they were developed under humid and warm climatic conditions associated with interglacial phases which have been correlatively attributed to marine oxygen isotope stages 11 and 9

the distribution of carbonate eolianite abstract carbonate eolianite forms distinctive coastal landforms on many mid latitude continents and islands numerous studies of extensive continental and smaller island deposits in both hemispheres have shown the eolianites are predominantly pleistocene in age the coorong coastal plain of south australia contains the world s longest record of eolianite deposition revealing that major phases of carbonate accumulation occurred during interglacial and some interstadial sea level highstands throughout the quaternary similarly the well studied eolianite islands of bermuda and the bahamas record a close match between dune accretion and sea level highstands since the middle pleistocene several other eolianite deposits appear to have formed at least partially during glacial periods the glacial age deposits are eolian reworked relict shelf or coastal sediments or remnants of former highly mobile coastal dunes sourced from low sea level shorelines the distribution and bioclastic composition of large scale eolianite deposits suggests carbonate production on shallow shelves and banks is the ultimate control on the formation of eolianite the bulk of the carbonate comprising those eolianites is heterozoan being produced where there is low terrigenous sediment input in dominantly temperate cool water and subtropical carbonate provinces quaternary cyclical movements of sea level have also controlled the form and rate of coastal carbonate deposition with repeated pulses of sedimentation during highstands forming laterally coalesced vertically stacked or composite dune successions major unconformities within the deposits are marked by paleosols which record hiatuses in coastal sedimentation in several regions major eolianite units overlie coastal deposits of terrigenous sediment those successions suggest that the trend towards aridity and reduction in the supply of terrigenous sediment to shelves during the quaternary has enhanced the production of carbonate and the deposition of eolianite

the relative motion between africa and eurasia as derived from itrf2000 and gps data 1 studies of intra and inter plate deformation typically need a model describing the motions of the stable part of the tectonic plates for reference purposes we have developed deos2k a model for the current motion of seven major tectonic plates derived from space geodetic observations this paper focuses on relative motion between africa and eurasia in the past this motion has been poorly established because of poor data coverage for africa deos2k is based on itrf2000 altamimi et al 2002 and new african gps observations it is an improvement over the nuvel 1a model for predicting the present day relative motions of these two plates deos2k predicts in northeastern africa that africa eurasia relative motion is about 40 smaller in magnitude than nuvel 1a and trends more to the northwest this is consistent with independent local geodetic observations a similar shift in orientation clockwise is observed at the western tip of the plate boundary

sedimentary and tectonic evolution of plio pleistocene alluvial and lacustrine deposits of fucino basin central italy abstract the fucino basin was the greatest lake of the central italy which was completely drained at the end of 19th century the basin is an intramontane half graben filled by plio quaternary alluvial and lacustrine deposits located in the central part of the apennines chain which was formed in upper pliocene and in quaternary time by the extensional tectonic activity the analysis of the geological surface data allows the definition of several stratigraphic units grouped in lower units and upper units the lower units upper pliocene are exposed along the northern and north eastern basin margins they consist of open to marginal lacustrine deposits breccia deposits and fluvial deposits the upper units lower pliocene holocene consist of interbedded marginal lacustrine deposits and fluvial deposits thick coarse grained fan delta deposits are interfingered at the foot of the main relief with fluvial lacustrine deposits most of the thickness of the lacustrine sequences more than 1000 m thick is buried below the central part of the fucino plain the basin is bounded by e w wsw ene and nw se fault systems velino magnola fault e w and tremonti celano aielli fault wsw ene and s potito celano fault nw se in the north the trasacco fault the pescina celano fault and the serrone fault nw se in the south east the geometry and kinematic indicators of these faults indicate normal or oblique movements the study of industrial seismic profiles across the fucino basin gives a clear picture of the subsurface basin geometry the basin shows triangular shaped basin fill geometry with the maximum deposits thickness toward the main east boundary fault zones that dip south westward serrone fault trasacco fault pescina celano fault on the basis of geological surface data borehole stratigraphy and seismic data analysis it is possible to recognize and to correlate sedimentary and seismic facies the bottom of the basin is well recognized in the seismic lines available from the good and continuous signals of the top of meso cenozoic carbonate rocks the shape of sedimentary bodies indicates that the filling of the basin was mainly controlled by normal slip along the nw se boundary faults in fact the continental deposits are frequently in on lap contact over the carbonate substratum several disconformable contacts occurred during the sedimentary evolution of the basin the main faults with antithetic and synthetic fault planes displace the whole sedimentary sequence up to the surface indicating a recent faults activity 1915 avezzano earthquake ms 7 0 the stratigraphic and tectonic setting of the fucino basin and neighboring areas indicates that the extensional tectonic events have had an important role in driving the structural sedimentary evolution of the plio quaternary deposits the geometry of the depositional bodies of the fault planes and their relationships indicate that the fucino basin was formed as a half graben type structure during plio quaternary extensional events some internal complexities are probably related to the fold and thrust structures of the apenninic orogeny formed in messinian time in this area and to a different activity timing of the e w and wsw ene fault systems and the nw se fault systems we believe based on the similarity of the surface characteristics that the structural setting of the fucino basin can be extrapolated to the other great intramontane basins in central italy e g rieti l aquila sulmona sora isernia basins

sedimentology and petrography of dredged carbonate sands from stocking island bahamas implications for meteoric diagenesis and aeolianite formation abstract piles of carbonate sand dredged onto stocking island exuma chain bahamas during world war ii are now relatively well lithified down to a depth of about 80 cm and may contain up to 8 of interstitial calcite cement a volume comparable to that measured from 1000 yr old beach ridges elsewhere in the bahamas rates of meteoric diagenetic changes are thus more rapid than previously assessed in this area 600 cm3 of calcite cement produced by m3 of rock per year preservation of hydrodynamic sedimentary structures footprints and the lack of aeolian bedforms e g dunes ripples on the surface of these sediments further show they have not been reworked by the wind at all therefore the carbonate aeolianites of holocene and pleistocene ages forming the bulk of the islands of bermuda and the bahamas were likely deposited during relatively dry periods when the effects of meteoric diagenesis were limited reduced moisture along with sediment availability and wind energy appears as a key player in carbonate aeolianite genesis

carbonate ramp depositional systems abstract the classification tectonic settings stratigraphy and early diagenesis of carbonate ramp systems are reviewed carbonate ramps are common in all geological periods but were dominant at times when reef constructing organisms were absent or inhibited ramps can be subdivided into inner mid and outer ramp environments the mid ramp zone extends from fair weather wave base to normal storm wave base although the water depths which these boundaries represent vary an additional outer slope environment occurs on distally steepened ramps as with siliciclastic shelves a range of wave storm and tide dominated ramps can be recognised and this forms the most convenient basis for ramp classification the carbonate productivity profile of ramps differs from that of rimmed shelves with the inner ramp showing lower production rates than comparable shallow water facies on rimmed shelves the zone of greatest organic carbonate sediment production appears to have shifted from the mid ramp to the inner ramp since the late jurassic carbonate ramps occur in most types of sedimentary basin but are best developed where subsidence is flexural and gradients are slight over large areas as in foreland and cratonic interior basins and along passive margins the featureless depositional profiles of many ramps means that sequence geometries are best observed on regional seismic lines some show low angle sigmoidal or shingled clinoforms suggesting that ramps may seldom be homoclinal but possess subtle slope geometries which reflect depositional environments because of their low angle slopes ramps respond differently to rimmed shelves during relative sea level changes although results seem to be strongly dependent on the rate of relative sea level change during a minor fall shallow ramp facies belts will simply shift basinwards in a forced regression in contrast the whole surface of a steep sloped flat topped rimmed shelf may be exposed so that sediment production ceases or is drastically reduced during a major fall shallow ramp bounded basins may empty completely conversely ramps also flood gradually whereas rimmed shelves do so more rapidly homoclinal ramps develop no resedimented lowstand deposits rimmed shelves and distally steepened ramps in contrast may develop lowstand talus or turbiditic wedges distally steepened ramps may behave more like homoclinal ramps during minor base level falls and like rimmed shelves during major base level falls many ramps consist of layered successions of several ramp sequences stacked one upon the other ramp stacks of this sort may show gross vertical accretion but individual ramp sequences seldom appear to develop in a keep up style apart from minor organic buildups as with many rimmed shelves steepening of the outer ramp margin due to tectonism slope inheritance or differential sedimentation may promote the development of a distally steepened ramp or rimmed shelf a wide variety of organisms have constructed buildups in mid and outer ramp environments isolated buildups may seed early in ramp development accrete to wave base or sea level and continue growth by stacking through successive ramp sequences so that depositional and diagenetic features within them are in concert with those of the shallow ramp the location of isolated buildups on ramps is governed by tectonism halokinesis antecedent topography or by the subtle slope geometry of the previous ramp sequence diagenesis on ramps shows some major variations compared with diagenesis on steep sloped flat topped carbonate platforms ramp bounded basins may form prolific petroleum sourcing and reservoiring systems and offer a range of subtle stratigraphic play types and lateral facies variations which determine reservoir quality and distribution isolated buildups in the mid and outer ramp environments represent one of the commonest petroleum reservoirs in ramp systems and tend to have their foundations in transgressive systems tracts grainstone and packstone reservoirs are widespread and range from shoreline carbonate sandbodies to major detached shoal complexes or shoals over offshore highs grainstone sandbodies occur in both highstand systems tracts and in prograding lowstand wedges

genesis of calcrete in quaternary soil profiles hutt and leeman lagoons western australia abstract soil profiles exposed along the margins of hutt and leeman lagoons contain a succession of calcrete horizons that exhibit oolitic pisolitic grainstone lithoclast breccia and pelloidal wackestone mudstone stone lithologies the typical coastal profile consists of an upper laminar calcrete horizon which is usually overlain by a transitional pisolitic loose soil horizon underlying the laminar calcrete is breccia and or massive calcrete downward gradation into the host is through a mottled calcrete horizon structure textures and fabrics are utilized to classify the following different calcrete types pisolitic loose soil is composed of sandy soils calcrete ooids and pisolites eolianite clasts and shell fragments laminar calcrete is composed of parallel laminated sheets of micritic carbonate that develop by segregation processes massive calcrete is dense relatively structureless calcrete with a secondary mudstone fabric resulting from diagenetic alteration of primary constituents calcrete mottles form in response to localized diagenesis in the host sediment breccia calcrete develops as a result of prolonged weathering involving repeated episodes of calcretization dissolution and brecciation diminution of permeability of the host sediment by development of massive calcrete is a major process in genesis of the profile and occurs in the lowermost part of the zone of alternate wetting and drying where the effect of water input overcomes the cumulative effects of evapotranspiration profile development is thereafter topographically controlled and restricted to horizons overlying the massive calcrete redevelopment of zones of alternate wetting and drying in older deposits may produce multiple soil profiles

the role of base level change in the dissection of alluvial fans case studies from southeast spain and nevada abstract tectonics climate and base level are the underlying controls of alluvial fan development on many fans base level is stable but where base level change occurs it may itself be a response to tectonics or climatic change tectonically induced base level change will be temporally independent of climatic change and will show spatial variability depending on the rate of propagation of tectonically induced regional dissection this is illustrated by the tabernas fans southeast spain the timing of climatically induced base level change follows the timing of climatic change itself and will show more consistency of spatial relationships within groups of fans affected alluvial fans which toe out in coastal zones or at lake shorelines may be influenced by climatically controlled base level changes conventionally a fall in base level would be expected to cause dissection of the distal fan zone however the reverse may occur with fan progradation taking place in response to a base level fall and dissection occurring in response to a base level rise two contrasted case studies are considered based in part on previously published work from dry region alluvial fan zones the coastal cabo de gata fans in southeast spain and the stillwater and cold springs fans in nevada usa in these areas base level changes occurred in response to late quaternary eustatic changes of sea level and changes in the levels of pluvial lakes respectively within both areas there are fans not affected by base level change cabo de gata west coast and inland fans cold springs fans and others where base level change has been important in fan evolution cabo de gata east coast fans stillwater fans the differences in geomorphic regime between those fans influenced by base level changes and those not are expressed in morphometric contrasts and different fan profile and plan characteristics within those fans influenced by base level changes the different mechanisms have influenced the location and elevation of the zone of incision the differences can be attributed in part to the temporal interactions of base level change with climatically induced changes in sediment supply and in part to differences in gradients of the foreshore exposed by the falling sea or lake base levels

coastal staircase sequences reflecting sea level oscillations and tectonic uplift during the quaternary and neogene many coasts feature sequences of quaternary and neogene shorelines that are shaped by a combination of sea level oscillations and tectonics we compiled a global synthesis of sea level changes for the following highstands mis 1 mis 3 mis 5e and mis 11 also we date the apparent onset of sequences of paleoshorelines either from published data or tentatively extrapolating an age for the uppermost purported oldest shoreline in each sequence including the most documented mis 5e benchmark we identify 926 sequences out of which 185 also feature holocene shorelines six areas are identified where elevations of the mis 3 shorelines are known and 31 feature elevation data for mis 11 shorelines genetic relationships to regional geodynamics are further explored based on the elevations of the mis 5e benchmark mean apparent uplift rates range from 0 01 0 01 mm yr hotspots to 1 47 0 08 mm yr continental collision passive margins appear as ubiquitously uplifting while tectonic segmentation is more important on active margins from the literature and our extrapolations we infer ages for the onset of formation for 180 coastal sequences sea level fingerprinting on coastal sequences started at least during mid miocene and locally as early as eocene whether due to the changes in the bulk volume of seawater or to the temporal variations in the shape of ocean basins estimates of eustasy fail to explain the magnitude of the apparent sea level drop thus vertical ground motion is invoked and we interpret the long lasting development of those paleoshore sequences as the imprint of glacial cycles on globally uplifted margins in response to continental compression the geomorphological expression of the sequences matches the amplitude and frequency of glacial cyclicity from middle pleistocene to present day moderately fast 100 000 yrs oscillating sea levels favor the development of well identified strandlines that are distinct from one another pliocene and lower pleistocene strandlines associated with faster cyclicity 40 000 yrs are more compact and easily merge into rasas whereas older cenozoic low frequency eustatic changes generally led to widespread flat lying coastal plains

space shuttle observations of open ocean oil slicks abstract we observed oil slicks along a ship wake in the northern arabian sea the slicks were recorded on photographs taken by astronauts onboard space shuttle columbia during mission sts62 in march 1994 the longest slick had a length of 21 25 km and an average width of 1 67 km the total volume of oil discharged into the sea was estimated at 108 37 m3 assuming a reasonable thickness of the oil film to be 3 1 m the oil slick width increased with the distance from the ship this image feature was converted into information in the time domain with the ship speed being a conversion parameter using this method we determined that the average oil slick spreading velocity with respect to the ship wake was 13 6 cm s 1 the analysis indicated that turbulent diffusion and wind drag were the dominant forcing for the oil slick spreading

tectonic connection of the hellenic and cyprus arcs and related geotectonic elements abstract the cyprus arc system forms part of a well defined presently active plate boundary and is a critical area for understanding the evolution of the eastern mediterranean sea the available seismic reflection profiles are utilised in order to establish the nature and origin of the main tectonic features of the arc which include 1 a the cyprus trench displaying evidence of underthrusting and morphostructural features typical of subduction zones 2 b the pytheus trench associated with right lateral strike slip movement and connecting the western end of the cyprus trench to the strabo trench sector of the hellenic trench system 3 c a predominantly transtensional fault zone connecting the easternmost part of the cyprus trench via the baer bassit overthrust zone in syria to the dead sea transform fault system 4 d a zone of complex deformation involving thrust and transform elements running from the misis mountains of southeast turkey through the kyrenia range in cyprus to the gulf of antalya and transected by roughly n s major shears notably the cape gelidonya anaximander mountains strike slip zone which appears to form the western boundary of the present active system of the cyprus arc the nature of the shallow structures associated with the cyprus arc is consistent with a geotectonic model involving some post miocene rotation of the south anatolian cyprus block probably induced by escape dynamics resulting from continent continent collision in eastern turkey and the development of the maras triple junction in southeastern turkey the alternation of plate boundary sectors respectively characterised by thrusting and strike slip displacement suggests that the shallow crust in this part of the eastern mediterranean is in a compartmented and relatively brittle state allowing accumulated boundary stresses to be accommodated largely by displacements and deformation along secondary features

a mediterranean holocene restricted coastal lagoon under arid climate case of the sedimentary record of sabkha boujmel se tunisia abstract the holocene sedimentary record of sabkha boujmel se tunisia is expressed by a shallowing upward carbonate lagoon tidal flat cycle 2 3 m thick unconformably overlying continental silt sandy sediment late wurmian in age the sedimentary package of this cycle starts with transgressive marginal shallow marine intertidal to subtidal bioclastic sands grading upwards to black mudstone rich in organic matter t o c up to 1 3 deposited within a lagoon protected from the sea by upper pleistocene lithified sand spits the uppermost part of the cycle is represented by oobioclastic carbonate sands covered with dead biodegraded microbial mats and or reddish sands of aeolian origin deposited in intertidal to supratidal environments the facies arrangement particularly the spatial distribution of the ancient and the more recent microbial mats records the progressive infilling of the lagoon as well as the progradation of the shoreline during the last 2000 years the organic rich facies which provide an age varying between 4130 and 6800 yr b p were deposited when the boujmel lagoon started to be progressively separated from the mediterranean sea the main factors controlling the facies and the thickness variation are the local topographic sea floor irregularities most likely controlled by the inheritance morphology resulting from an important fluviatile digging that occurred during the last glacial maximum the relative sea level fluctuations the hydro isostatic rebound and the climate

beachrock a tool for reconstructing relative sea level in the far field abstract today s understanding of sea level change developed through a combination of process based physical modelling and observational data observational data of sea level change derives from coral reefs in the far field of the former ice sheets where a geographically variable relative sea level signal is expected as a response of the earth to ocean loading given this variability and the limited geographical distribution of coral reefs there is a need to explore other non coral based sea level markers to further understand sea level change and for example to fingerprint melt water here we present beachrock as a coastal deposit suitable for relative sea level rsl observations in the far field beachrock is an intertidal deposit forming in the zone where carbonate saturated meteoric and marine water mix and p co 2 decreases we provide the conceptual framework for beachrock analysis and describe techniques suitable for analysing and dating the deposit the approach is standardised by outlining the sediment characteristics in terms of rsl indicative meaning and indicative range and is tested against published data a study conducted on coasts of the mediterranean sea exemplifies the utility of beachrock for rsl reconstruction it is shown that the precision of the reconstruction is derived from the combined uncertainty of age and tidal amplitude or tidal range the uncertainty can be reduced to half the tidal amplitude when a deposit can be ascribed to the upper or lower intertidal zone beachrock based data benefit from the lack of non quantifiable error terms such as post depositional compaction due to the instantaneous formation and high preservation potential of the deposit this underlines the high precision of beachrock based rsl reconstruction which is a prime requirement for testing and extending coral based records

plio pleistocene cliff bound wedge shaped warm temperate carbonate deposits from rhodes greece sedimentology and facies abstract the pliocene to pleistocene temperate carbonates of rhodes were deposited in a tectonically active region strongly influenced by a complicated and rapidly changing topography provided by the highly tectonised late cretaceous lindos limestone as basement rock deposition on this basement took place in accommodation loci restricted to micrograbens and their downslope extension to the foot of steep submarine cliffs to basement neptunian dykes and depressions in the basement rock consequently the sediments comprise a high degree of facies variability and are typically thin and laterally discontinuous the integration of several outcrops is necessary for the reconstruction of the stratigraphy and the relative sea level changes the sediments were deposited during a large scale tectonically driven transgressive regressive cycle in water depths changing from zero to several hundreds of metres at the studied lindos pefkos road cutting the kolymbia limestone bound to the foot of lindos limestone cliffs marks the onset of the marine deposition in the late pliocene its fabric is a rudstone consisting of unsorted angular lindos limestone clasts up to boulder size with a matrix dominated by molluscs and coralline algae the overlying plio pleistocene st paul s bay limestone consists of deep water float and rudstones containing the white coral community dominated by the coral lophelia pertusa its matrix shows a complex fabric of up to five sediment zones separated by differing states of lithification in this maximum flooding phase mineralised hardgrounds indicate depositional hiati the subsequent shallowing phase is represented by the cape arkhangelos calcarenite a series of distinctive facies of very patchy distribution they are characterised by the bryozoan brachiopod facies overlain by a facies heavily dominated by the bivalve mytilaster sp mytilaster facies conspicuous for the mytilaster facies is the inverse concave up stacking pattern of shelly material this facies is followed by a serpulid framestone and associated serpulid rudstone neptunian dykes cut through the first two facies and are filled with an intraformational breccia grading into a breccia with abundant mytilaster facies clasts neptunian dyke facies the sedimentology and interpretation of each facies include a description of the ichnology in particular the bioerosion peculiar to each facies the separation of different gravity transport processes in steep submarine environments is rarely described and most of the literature concentrates on siliciclastic dominated coarse grained sandy or gravely sand delta environments for a classification of the transport processes of the examined deposits the following criteria were evaluated sediment body symmetry inclination of the palaeorelief sediment constituents fabric complexity sedimentary structures and availability of fine matrix sedimentary structures and grading can be camouflaged in carbonates due to density differences of bioclasts however bioclast orientations such as bivalve stacking patterns can give information about the sedimentary process we suggest the inverse concave up stacking pattern of bivalve shells to be a texture potentially indicative for debris falls because of the above mentioned criteria we classified the kolymbia limestone as rock fall deposits and the st paul s bay limestone as well as the mytilaster facies of the cape arkhangelos calcarenite as debris fall deposits the bryozoan brachiopod facies could not be classified with certainty because of the lack of sedimentary structures and bioclast orientation however a grain flow or most likely a debris fall transport process seems probable

the role of the kyrenia range lineament cyprus in the geological evolution of the eastern mediterranean area rewarding insights into major crustal lineaments come from the integrated study of well exposed examples one is the kyrenia range a narrow arcuate lineament of several hundred kilometres in length comprising northern cyprus and its offshore extension the kyrenia range consists mostly of mesozoic and tertiary sedimentary and subordinate volcanic and metamorphic rocks disposed in four rock groups separated by unconformities recording deformation events the lineament is dominated by a steeply dipping composite thrust pile located partly along and partly straddling the abrupt northward termination of crust similar to the troodos igneous complex at depth the 200 ma history of the lineament involved episodic rift passive margin active margin strike slip and uplift phases the area was rifted off gondwana in the late triassic to form a southerly turkish microcontinent capped by a gently subsiding carbonate platform after formation of a small ocean basin to the south during the cretaceous troodos ocean northward subduction began santonian the first major deformation d1 is attributed to pervasive dextral strike slip which removed the mesozoic passive margin and brecciated and metamorphosed the remaining platform in the maastrichtian and early tertiary the area subsided and scree breccias were shed from scarps into pelagic carbonate depositing seas while bimodal within plate type lavas were erupted in an extensional setting influenced by strike slip by mid eocene time shortening first evidence by flysch and olistostrome deposition culminated in strong southward thrusting d2 and localized metamorphism northward subduction south of cyprus ensued and the range lay in an extensional fore arc setting in late eocene and miocene time the area then subsided dramatically and accumulated thick turbidite sequences derived from eroding tauride mountain areas to the northeast faulting and general uplift in the late miocene was followed by renewed compressional deformation climaxing in mid pliocene time d3 with large scale thrusting and tilting pulsed vertical uplift continued through the quaternary similar volcanic and metamorphic rocks formed along the kyrenia lineament at intervals sedimentary rocks emerge as the most sensitive tectonic setting indicators long lived lineaments like the kyrenia range are inherently very complicated and perceived simple solutions in other cases should be viewed with some scepticism

raised pleistocene marine terraces of the crotone peninsula calabria southern italy facies analysis and organization of their deposits abstract wide marine terraces well known in the italian literature are present in the crotone peninsula ionian calabria they are related to the interplay between pleistocene sea level changes and the progressive uplift of the calabrian arc from the middle pleistocene onwards we present a description of facies organization and stratigraphical characteristics of the terrace deposits along with a new geological map of the area all the marine terraces unconformably overlie a plio pleistocene slope succession known as cutro clay the oldest and highest terrace named cutro terrace is placed between 90 and 200 m of elevation and is gently inclined south eastwards four younger terraces placed at progressively lower elevations and dipping seawards at low angles have been recognized the sedimentary deposits of the terraces are represented by mixed carbonate and siliciclastic bodies up to 10 m thick algal reefs and grainstone to rudstone deposits are common in the south eastern part of the study area whereas mostly siliciclastic sandstone units of shoreface environments are more abundant northwards and westwards the deposits of some terraces are made up of minor cycles bounded by subaerial transgressive and flooding surfaces referred to minor sea level fluctuations nne ene e and wnw trending normal fault systems are present within the study area and dissect the marine terraces specifically the activation of ene trending faults took place after the formation of the oldest terrace but prior to the formation of the younger terraces

sedimentary development and correlation of late quaternary terraces in the kyrenia range northern cyprus using a combination of sedimentology and optical luminescence data this study focuses on the younger of a series of quaternary terraces along the flanks of the kyrenia range in northern cyprus specifically the kyrenia girne and the koupia terraces the kyrenia girne terrace is tentatively correlated with oxygen isotope stage 5 125 ka and the koupia terrace with oxygen isotope stage 3 50 ka along the northern flank of the range the kyrenia girne terrace deposits 5 20 m above modern sea level typically begin with a basal lag conglomerate and then pass upwards into shallow marine calcarenites and then into variable aeolianites paleosols and fluvial deposits up to 20 m thick in contrast the koupia terrace 2 m above modern sea level consists of aeolianites and shallow marine calcarenites up to 8 m thick the equivalent deposits along the southern flank of the range are entirely non marine fluvial mud sands and conglomerates the marine to continental terrace systems can be tentatively correlated based on mapping height above modern sea level and sedimentary facies however variable preservation and patchy exposure require such correlations to be independently tested to achieve this a portable optically stimulated luminescence osl reader was used to determine the luminescence characteristics of the two terrace systems luminescence profiles show major differences in luminescence characteristics between the two terrace depositional systems which can be related to sedimentary processes provenance and age these features allow sections in different areas to be effectively correlated individual sections show luminescence properties that are generally consistent with an expected up sequence decrease in age however the younger koupia terrace deposits show higher luminescence intensities compared with the older kyrenia girne terrace deposits this can be explained by multiple phases of reworking of the kyrenia girne terrace deposits which changed the luminescence characteristics of the sediment the use of the portable osl reader is therefore an effective means of correlating late quaternary terrace deposits in northern cyprus and probably also elsewhere

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

structural development of the central kyrenia range north cyprus in its regional setting in the eastern mediterranean region a detailed structural analysis of the mesozoic cenozoic geological development of the central segment of the kyrenia range in its regional tectonic context is given here the structural evidence comes from five structural traverses outcrop observations small scale structures and related regional evidence the majority of the structures are fault planes of which a subordinate number exhibit slickenlines fault plane data n 2688 with kinematics n 537 additional kinematic data were obtained from c s fabrics and folds small scale structures in each stratigraphic unit were backstripped to reveal relative chronology synthesis of the structural information indicates three phases of convergence related deformation 1 late cretaceous associated with greenschist facies metamorphism followed by exhumation that was probably associated with wnw ese to ene wsw trending high angle faulting 2 mid eocene associated with southward thrusting coupled with n s strike slip transfer faulting and oblique faulting in an overall sinistral transpressive stress regime 3 late miocene earliest pliocene involving southward thrusting and folding localised back thrusting extensive fault reactivation and large scale segmentation of the range intense uplift of the kyrenia range took place during the plio pleistocene possibly related to the collision of the eratosthenes seamount with the cyprus trench to the south of the island the three main convergent phases relate to stages of northward subduction and diachronous continental collision affecting the northerly active continental margin of the southern neotethys

late eocene neogene sedimentary geology of the girne kyrenia range northern cyprus a case history of sedimentation related to progressive and diachronous continental collision abstract sedimentary geology can shed light on the processes of continental collision the easternmost mediterranean provides an exceptional opportunity to study sediments deposited during progressive and diachronous continental collision with implications for comparable settings elsewhere here we focus on sediment sources pathways and deposition of mostly deep sea clastic sediments exposed in northern cyprus the sedimentary basin forms part of the northern continental margin of the southern neotethys ocean and is represented by a ca 200 km long e w trending arcuate lineament encompassing northern cyprus and its submarine link with turkey the upper eocene upper miocene basin was divided into northerly and southerly sub basins during mid to late miocene time by an e w trending inferred syn depositional fault lineament the sequence begins with non marine to shallow marine basal conglomerates late eocene that abruptly fine upwards into siliciclastic turbidites oligocene followed by biogenic calciturbidites and marls aquitanian langhian during mid late miocene the northerly sub basin was characterised by thin to medium bedded calciturbidites and marls serravallian overlain by thick bedded medium grained lithic sandstones tortonian in contrast the southern sub basin is dominated by siliciclastic turbidites with abundant sole structures burdigalian tortonian palaeocurrent evidence indicates dominantly westward sediment transport especially during the late miocene the serravallian tortonian sandstones of the northern sub basin are relatively rich in carbonates while the southern sub basin contains more siliciclastic and ophiolite derived detritus indicating differences in sediment supply in general the upper eocene basal conglomerates were mainly derived from the north from within the girne kyrenia range and its inferred northward extension in response to rapid subsidence reflecting possible southward subduction zone retreat clastic sediment sources to the north then submerged while clastic sediment was instead mainly supplied from the south neotethyan suture zone to the east and northeast in southern turkey reflecting diachronous collision deep water deposition persisted in the easternmost mediterranean basin further west until this was terminated in northern cyprus by thrusting folding during latest miocene earliest pliocene quaternary collision related uplift ensued similar sedimentary development is to be expected in collisional settings elsewhere e g tethyan closure in the himalayas iapetus closure in the appalachians

lithofacies and palaeosol analysis of the middle and upper siwalik groups plio pleistocene haripur kolar section himachal pradesh india abstract the middle upper siwalik groups plio pleistocene are exposed at haripur kolar himachal pradesh india the succession is 2800 m thick and has been subdivided into unit m1 of the middle siwalik and four units u1 u4 of the upper siwalik group on the basis of facies associations and type and degree of development of palaeosols the available magnetostratigraphic ages for bases of units u1 u3 and u4 are 5 5 2 6 and 1 77 ma respectively the top of the section has been dated as 19 ka lithofacies association and palaeocurrent analysis indicates that the middle and upper siwalik groups were formed mainly by a basin transverse fluvial system two types of river systems which differ in their size can be documented in unit m1 unit u1 and unit u2 one trunk river system similar to the modern kosi and the other smaller river system which formed tributaries to the former the large rivers were mainly braided in nature the unit u3 and lower part of unit u4 were deposited in the piedmont depositional system mainly by small braided streams and the upper part of the unit u4 was deposited during a period of arid climate by sediment gravity flows integration of fluvial lithofacies and pedofacies helps to identify two fluvial depositional systems from the modern indo gangetic plains the lowland system involved deposition on alluvial megafans and interfan areas which resulted in sand rich and mud rich sequences with weekly developed soils the upland system allowed large tracts to act as high ground for thousands of years thereby giving rise to sandstone poor intervals with moderately to strongly developed soils occurrence of moderately to strongly developed soils was controlled by uplifting and tilting of large tectonic blocks without any relation to distance from the main channels rate of subsidence apparently controlled the occurrence of lowland and upland systems deposition of the unit m1 unit u1 and unit u2 took place under upland and lowland systems very similar to those identified from the modern indo gangetic plains the warm and humid climate between 5 3 and 2 6 ma led to the formation of red alfisols with calcrete nodules at places slightly cooler and drier climate starting at about 2 6 ma and approximately coinciding with the onset of global scale glaciation produced poorly developed yellow soil with common development of nodular calcretic horizon and calcitc material disseminated in the groundmass at ca 0 9 ma a probable significant change to still drier and cooler climate produced typical sediment gravity flows in the piedmont system that continued until at least up to 19 ka

pleistocene terrace deposition related to tectonically controlled surface uplift an example of the kyrenia range lineament in the northern part of cyprus abstract in this study we consider how surface uplift of a narrow mountain range has interacted with glacial related sea level cyclicity and climatic change to produce a series of marine and non marine terrace systems the terrace deposits of the kyrenia range record rapid surface uplift of a long lived tectonic lineament during the early pleistocene followed by continued surface uplift at a reduced rate during mid late pleistocene six terrace depositional systems are distinguished and correlated along the northern and southern flanks of the range termed k0 to k5 the oldest and highest k0 terrace system is present only within the central part of the range the k2 k5 terrace systems formed later at sequentially lower levels away from the range the earliest stage of surface uplift k0 terrace system comprises lacustrine carbonates interbedded with mass flow facies early pleistocene the subsequent terrace system k1 is made up of colluvial conglomerate and aeolian dune facies on both flanks of the range the later terrace systems k2 to k5 each begin with a basal marine deposit interpreted as a marine transgression deltaic conglomerates prograded during inferred global interglacial stages overlying aeolian dune facies represent marine regressions probably related to global glacial stages each terrace depositional system was uplifted and preserved followed by subsequent deposits at progressively lower topographic levels climatic variation during interglacial glacial cycles and autocyclic processes also exerted an influence on deposition particularly on short period fluvial and aeolian deposition

development of a prograding carbonate wedge during sea level fall lower pleistocene of rhodes greece a lower pleistocene carbonate platform is described from north east rhodes greece it comprises a succession of warm temperate calcarenites the cape arkhangelos calcarenite facies group developed in a steep sided coastal basin the depositional setting for the sediments is a carbonate wedge developed within a larger scale forced regression deposition began with aggradation of storm dominated lower and upper shoreface deposits later the development of a prograding platform produced giant clinoform foresets a marked alternation of cross bedded and bioturbated clinoforms indicates seasonal transport of carbonate material off the platform periodically the platform edge has been deeply scoured by exceptional storms after which further deposition repaired the platform margin and progradation resumed more than 20 such major storm cycles are preserved applying sequence stratigraphy to this succession leads to two different possible interpretations one with a lowstand systems tract and one with a forced regressive systems tract depending on the scale of view the implications of this are discussed the present example shows clearly that the application of sequence stratigraphic models to real carbonate sequences requires careful consideration of scale and context before interpretations are made

chronology of pleistocene sedimentary cycles in the carmel coastal plain of israel abstract the eastern mediterranean coastal plain of israel is composed mainly of loam and sand and gravel of pleistocene to holocene age supplemented by an upper pleistocene beach rock horizon indicating an alternation of marine coastal and continental environments owing to the complexity of the numerous exposures of aeolianites kurkar and soils hamra in the elongated ridges along the coastal plain it is difficult to set up a reliable stratigraphy a systematic luminescence dating study was carried out on loose sand kurkar and hamra deposits in the coastal plain between netanya and haifa in this study 33 samples were investigated from key sections along the carmel coast the chronological results are in excellent agreement with the geological estimates five periods of sand accumulation and kurkar formation can be distinguished at about 140 130 90 and around 60 ka and between 60 and 50 ka hamra formation took place between 140 and 130 ka around 80 65 and 60 ka and between 20 and 12 ka the beach rock is correlated with the sea level maximum during ois 5e the luminescence dating results indicate that neither kurkar nor hamra formation correlates with glacial and interglacial periods of the northern hemisphere however the chronological succession of these climate related cycles is in good agreement with marine and terrestrial archives in the eastern mediterranean

palaeoclimate and palaeoenvironmental responses in the western mediterranean over the last 140 ka evidence from mallorca spain climatic change in the western mediterranean basin over the last 140 ka has been investigated from sediment and soil sequences along the coast of the northeastern part of mallorca spain palaeoclimate and palaeoenvironments are reconstructed from sediment and soil structures marine and terrestrial molluscan fauna grain size distributions mineral magnetics sediment and soil chemistry sem and oxygen isotope values dating is by osl and amino acid geochronometry along with marine molluscan faunal assemblages all oxygen isotope stages and substages from ois 6 to 1 are recorded mean annual temperatures m a t of c 19 2 c for the climatic optimum of the last interglacial compare with c 17 3 c for the present and are associated with high sea level extensive woodland and stable soils although wide temperature ranges are detected during this stage with values as low as c 10 3 c through ois 5d to 5a m a t fluctuated from 8 2 c to 17 9 c low sea level open vegetation effective river activity and aeolian sand and dust deposition characterize 5d and 5b while relatively high sea level and soil development on stable landscapes dominate ois 5c and 5a ois 4 is represented by m a t of c 4 9 c with aeolian sand and loess deposition limited river activity and weak soil development loess deposition persisted into ois 3 but at this time the m a t was c 13 c and with higher humidity and vegetation growth during the lgm ois 2 m a t was c 8 1 c and effective river slope and aeolian processes along with associated with limited vegetation cover were responsible for the most extensive changes in the landscape major rates of change occur during periods of climatic deterioration when the high levels of geomorphic energy were imposed on a landscape undergoing a breakdown of vegetation cover

the oligocene recent evolution of the mesaoria basin cyprus and its western marine extension eastern mediterranean abstract the neogene stratigraphic and structural evolution of the mesaoria basin and kyrenia range is studied using multi channel seismic reflection profiles from their western marine extension the region north of the front of the troodos larnaka culmination constitutes a crustal scale s verging thick skinned linked imbricate thrust system comprising most of the forearc region north of the present day cyprus arc in the eocene thrust activity gave rise to the prominent growth of the troodos larnaka culmination and concurrent imbrication further north in the forearc region creating the root of the kyrenia fold thrust belt northward retreat of the active thrust front in the oligocene miocene led to the development of a foredeep across the root of the kyrenia fold thrust belt with a prominent depositional foredeep ramp situated at the current front of this belt crustal contraction continued in the miocene along the front of the troodos larnaka culmination leading to the progressive shoaling of the basin carried on the backlimb of this culmination in the late miocene thrust activity became widespread in the forearc region with structural contraction being focussed on the kyrenia fold thrust belt pliocene thrust activity in the forearc region is primarily focussed on the kyrenia fold thrust belt with much uplift occurring in the mid late pliocene but continuing to the present the mesaoria basin evolved in the miocene to pliocene as a piggy back basin our data negate earlier models that postulate a phase of crustal extension in the forearc region during the oligocene to mid late pliocene

arid climate 2 5 ma in the plio pleistocene valdarno basin northern apennines italy abstract distinctive eolian dominated sandy deposits 35 m thick exposed along the sw margin of the plio pleistocene valdarno basin in the northern apennines italy reflect an unusually arid period in the region paleomagnetic investigation and 40 ar 39 ar dating of a tephra layer 10 m above the eolian sand suggest that the sand was deposited between about 2 7 and 2 4 ma this age is coeval with the global climatic deterioration that occurred at the middle upper pliocene transition eolian sediments are represented by cross bedded sand rippled sand and horizontal bedded sand the alluvial deposits associated with the eolian sediment consist of sheet like beds of coarse sand and erosively based pebbly sand bodies eolian sand together with fluvial sandy deposits was formed in the medial distal portion of an alluvial system and represents the rena bianca sand unit the eolian and alluvial deposits are arranged into sedimentary cycles 2 6 m thick displaying a wetting drying wetting upward trend recording second order climatic oscillations of ca 40 ka each cycle is enclosed between major bounding surfaces defined by iron mineral encrustations these bounding surfaces represent periods of reduced eolian sand accumulation caused by a rising water table during the 2 5 ma global cooling the valdarno basin experienced a period of arid conditions owing to the influence of cold and dry easterly and northeasterly winds in contrast during the pleistocene the uplift of the pratomagno ridge protected the valdarno basin from easterly and northeasterly winds giving rise to relatively warm and wet conditions and mitigating the regional and global climatic changes

self reversed magnetization held by martite in basalt flows from the 1 1 billion year old keweenawan rift canada in some basalt flows of the 1 1 billion year old keweenawan rift exposed at mamainse point ontario there is a magnetic phase that holds a remanence antiparallel to the populations of magnetite and hematite that are typical of flows in the succession the paleomagnetic and geological context of this component demonstrates that it is not a chemicaloverprint whoseremanence is attributableto a subsequently reversed geomagnetic field but that the component is a self reversal of the primary magnetization here we use rock magnetic experiments and mossbauer spectroscopy to show that this phase occurs in the most oxidized flowsandisheldbya fine grainedpopulationofhematitethatacquiredits self reversedremanencethrough interactions with a phase of lower blocking temperature we propose that this self reversed hematite is a manifestation of the self reversal phenomena that has been observed to occur experimentally during the transformation of maghemite to hematite and thathas been attributed to negative exchange coupling across the crystal lattices we suggest that hematite formed in association with iron silicates in the basalt flows carries a remanence reflective of the field in which it formed but that martite hematite pseudomorphed after magnetite which formed through the progressive oxidation of magnetite to maghemite with subsequent inversion to hematite carries the self reversed remanence this study marks the second time that a naturally occurring self reversed magnetization has been attributed to this mechanism and marks the oldestreportedinstanceof anytypeof self reversedremanence themartitethatformsthrough thisprocess has the ability to retain a record of the negative exchange coupling from the time of its formation for hundreds of millions of years

climatically controlled terraces in uplifting mountain areas abstract terraces in tectonically active mountains and uplands record both tectonic uplift and rhythmic climatic variations the author discusses the question of how to distinguish the role of both tectonic and climatic factors in central europe with quaternary uplift of the order of 50 100 m climatically controlled terraces are well developed cold stage aggradation is recognised through the interfingering of periglacial alluvial slope and loess deposits erosional activity prevailed in transitional periods then follows a discussion of difficulties connected with the construction of timing and rate of tectonic uplift based on the depth of incision in the bedrock and on facies differentiation the examination of changes in longitudinal profiles of river valleys indicates that unrejuvenated upper valley courses cannot be used for the reconstruction of tectonic uplift finally the author presents several types of adaptation of tectonically determined downcutting and aggradation to quaternary climatic cyclicity

tectonic impact on the fluvial deposits of plio pleistocene himalayan foreland basin india abstract the himalayan foreland basin comprises a number of subbasins developed in various sedimentary environments during the plio pleistocene phases of himalayan orogeny this paper describes the evolutionary processes that led to the development of the himalayan foreland basin in the dehra dun and subathu subbasins the dehra dun subbasin essentially consists of conglomerate facies whereas subathu subbasin is primarily composed of sandstone mudstone intercalated with conglomerate the two subbasins were sites of braided river systems evidence from chronostratigraphy provenance and tectonic and climatic conditions suggests that differential tectonic movement sedimentation rate and basin subsidence coupled with climatic variation were responsible for the contrasting fluvial facies in these subbasins following the merger of the two subbasins at about 5 23 ma the conglomerate facies assemblage of the dehra dun subbasin passes laterally into a sandstone mudstone conglomerate facies assemblage of the subathu subbasin thickly bedded amalgamated sheet conglomerate of dehra dun subbasin has a high sedimentation rate 0 70 mm year between 5 23 and 4 8 ma with a slow rate of basin subsidence in contrast a slow sedimentation rate 0 39 mm year in coeval sediments of the subathu subbasin with relatively fast subsidence produced a succession of thick multistorey sandstone body with mature paleosols petrographic and clast composition data from dehra dun subbasin suggest that the detritus was derived from the pre tertiary lesser himalayan sequence lying in the north during an active tectonic phase of the main boundary thrust between 4 8 and 1 77 ma progradation of posttectonic conglomerate of the dehra dun subbasin continued during a quiescent phase of the main boundary thrust however as a consequence of partitioning of subathu subbasin along the intra foreland thrust interfingering of buff piedmont drainage and grey trunk drainage sandstones took place in contrast the syntectonic conglomerate of subathu subbasin originated from the uplifted proximal part of the foreland basin tertiary belt during the active phase of intra foreland thrust around 1 77 ma

climatically controlled river terrace staircases a worldwide quaternary phenomenon a comparison of fluvial terrace sequences from around the world based on data collected as part of international geoscience programme igcp project no 449 has revealed significant patterns river terraces provide important records of uplift which is essential for their formation and of landscape evolution their cyclic formation however almost invariably seems to have been a response to climatic fluctuation sequences in the european core area of igcp 449 which has the longest and most extensive research history have been used as templates for worldwide comparison there is evidence for a global acceleration of uplift at the time of and perhaps in response to the mid pleistocene revolution when climatic fluctuation switched to 100 kyr milankovitch cycles terraces formed prior to this generally consist of wide aggradational sheets that probably each represent formation over several 41 kyr cycles subsequently river valleys became more steeply entrenched and terraces formed in response to the stronger 100 kyr climatic forcing in many cases at approximately one per cycle this paper uses the new data resource to explore differences between records in different climate zones between sequences with variable numbers of middle late pleistocene terraces and between systems in which the all important incision event has occurred in different parts of climatic cycles key records discussed include european examples from the rhine thames somme dniester dnieper don volga and aguas from asia the gediz turkey and orontes syria from north america the south platte and colorado from south africa the vaal and sundays from australia the shoalhaven and from south america the amazon paraguay and tributaries of the colorado and negro

interpreting the response of a dryland river system to late quaternary climate change abstract a u series calcrete chronology has been constructed for three late quaternary terrace units termed the d1 d2 and d3 terraces in age descending order from the rio aguas river system of the sorbas basin southeast spain the d1 terrace formed between 30 300 4400 year bp and 12 140 360 year bp correlating well with the last glacial maximum when rates of sediment supply would have increased greatly because of higher rates of weathering reduced vegetation cover and weak soil development the d2 terrace formed between 12 800 1100 year bp and 9 600 530 year bp correlating well with the younger dryas event the d3 terrace could only be poorly constrained to the early holocene and no unequivocal cause could be assigned to this period of aggradation the sedimentology and geomorphology of the d2 terrace suggests however that the aggradation of this unit was a response to diapirism karstic processes occurring within the underlying messinian gypsum strata and the subsequent damming of the aguas system therefore despite its coincident occurrence with the younger dryas aggradation of the d2 terrace is unrelated to climate change the style of this response controlled predominantly by the characteristics of the underlying bedrock makes correlating the terrace record of the aguas with other systems in the mediterranean unreliable this study therefore highlights the problems of correlating fluvial sequences in regions of variable tectonics climatic history and bedrock geology and emphasises the need to properly understand the main controls on individual fluvial systems before any attempt is made to correlate their depositional histories

pleistocene geomorphological and sedimentary development of the akaki river catchment northeastern troodos massif in relation to tectonic uplift versus climatic change the uplift of the troodos ophiolite is reflected in the development of the akaki river catchment in the northeast troodos massif four main stages f1 f4 of geomorphological terrace development and related deposits are recognised using satellite imagery and field observations the geomorphological terraces have been tectonically uplifted during the pleistocene so that they dip northwards from the troodos mountains until they merge with the mesaoria plain lithology e g hard diabase versus soft extrusive rock has exerted an important control on the geomorphology of the akaki river channel the f1 terraces and related deposits are well preserved in the lower reaches of the catchment the f2 terraces are more widely preserved but with few preserved deposits the f3 erosional surfaces e g strath terraces and related deposits are widespread up into the higher reaches of the catchment the f4 to recent geomorphological surfaces and deposits are confined to near the modern river channel the f1 to f3 aged deposits each include very high energy mass flow deposits and somewhat lower energy traction flow deposits with minimal sand preservation stages of fluvial aggradation were followed by soil development e g terra rossa the f1 to f4 aged terraces and related deposits mainly formed in response to a combination of very long term tectonic uplift and climatic related change long term and short term tectonic uplift was the dominant driver related to the updoming of the troodos ophiolite especially during the earlier time period f1 and f2 whereas climate related effects appear to have dominated more recently f3 and f4 sedimentary aggradation is likely to have predominated during interglacial periods while interglacial glacial transitions when climate fluctuated are seen as times of increased incision previous correlations of the f1 f4 fluvial deposits with similar deposits elsewhere in cyprus including coastal marine carbonate deposits suggest that the f1 and f2 deposits are likely to be of middle pleistocene age and the f3 f4 deposits of late pleistocene to holocene age