the mis 5 5 terraced deposit of fosso del cupo montecelio central italy and its mousterian lithic assemblage re evaluation of a nineteenth century discovery abstract by means of a geomorphological study and the correlation with the geochronologically constrained terraced deposits of the greater area of rome we attribute to the aggradational phase during marine isotopic stage mis 5 5 a terraced deposit firstly described in the earliest local geological reports of the 19th century in which a small set of lithic artifacts and vertebrate fossil remains was recovered after this correlation the sedimentary deposit of fosso del cupo represents the only inland occurrence of an aggradational deposit of mis 5 5 so far recognized in the area of rome where a rich record of lithic industries and faunal assemblages has been yielded by the sedimentary successions deposited in response to deglaciation during sea level rises of mis 15 through mis 7 we have implemented the lithic and faunal assemblages through a collection during the geological survey performed in the area where the terraced deposit crops out with an age tightly constrained around 125 ka the lithic industry and the faunal assemblage from fosso del cupo although limited in number represent an important witness of the early development of the local pontinian culture and should be considered a regional marker which may concur to improve the knowledge on the mousterian of central italy

the early pleistocene human dispersals in the circum mediterranean basin and initial peopling of europe single or multiple pathways abstract the issue of ancient human single or multiple dispersal pathways into eurasia is theoretically significant for understanding adaptive processes involved in peopling vacant spaces and varied unfamiliar ecosystems but receives mostly marginal attention the western asian staging post remains most plausible whereas an alternative peopling directly from the maghreb across the gibraltar strait into iberia and beyond though problematic is proposed repeatedly the present review discusses these issues and findings requiring interpretation with respect to chronology fossil human and palaeolithic evidence and early pleistocene circumstances in the circum mediterranean basin and europe the spatiotemporal distribution of palaeoanthropological occurrences and ethiopian fossil mammal expansions does not support the hypothesis of a single early pleistocene biogeographic event originating in subsaharan africa spreading throughout western asia and europe on the other hand this spatiotemporal distribution of ancient human evidence in europe reveals an intriguing bimodal chronological pattern early pleistocene occurrences in both eastern europe and western europe prove earlier than those in west central europe and the italian peninsula which are dateable to the mid pleistocene this early pleistocene distribution cluster of occurrences in iberia and atlantic europe refutes implicitly a single linked human ethiopian mammal biogeographic event exclusively through western asia while reviving the notion of sweepstake dispersal directly across the strait of gibraltar a scenario which however demands independent confirmation by reviewing past circumstances favourable for a crossing as well as suggesting a series of multiple staging posts the observed bimodal spatiotemporal configuration becomes more compatible with another hypothesis namely that europe was peopled independently by converging population movements from both the western asian and ibero moroccan staging posts during the early pleistocene between ca 1 85 1 40 ma

late stage dolomitization of the lower ordovician ellenburger group west texas abstract petrography of the lower ordovician ellenburger group both in deeply buried subsurface cores and in outcrops which have never been deeply buried documents live generations of dolomite three generations of microquartz chert and one generation of megaquartz regional periods of karstification serve to subdivide the dolomite into early stage which predates pre middle ordovician karstification and late stage which postdates pre middle ordovician karstification and predates pre permian karstification approximately 10 of the dolomite in the ellenburger group is late stage the earliest generation of late stage dolomite dolomite l1 is interpreted as a precursor to regional dolomite l2 l1 has been replaced by l2 and has similar trace element o c and sr isotopic signatures and similar cathodoluminescence and backscattered electron images it is possible to differentiate l1 from l2 only where cross cutting relationships with chert are observed replacement dolomite l2 is associated with the grainstone subarkose and mixed carbonate siliciclastic facies and with karst breccias the distribution of l2 is related to porosity and permeability which focused the flow of reactive fluids within the ellenburger fluid inclusion data from megaquartz interpreted to be cogenetic with dolomite l2 yield a mean temperature of homogenization of 85 6 c on the basis of temperature 18owater plots temperatures of dolomitization ranged from approximately 60 to 110 c given estimates of maximum burial of the ellenburger group these temperatures cannot be due to burial alone and are interpreted to be the result of migration of hot fluids into the a ea a contour map of 18o from replacement dolomite l2 suggests a regional trend consistent with derivation of fluids from the ouachita orogenic belt the timing and direction of fluid migration associated with the ouachita orogeny are consistent with the timing and distribution of late stage dolomite post dating dolomite l2 are two generations of dolomite cement c1 and c2 that are most abundant in karst breccias and are also associated with fractures subarkoses and grainstones 87sr 86sr data from l2 c1 and c2 suggest rock buffering relative to sr within dolomite l2 and a retention of a lower ordovician seawater signature while cements c1 and c2 became increasingly radiogenic it is hypothesized that reactive fluids were pennsylvanian pore fluids derived from basinal siliciclastics the precipitating fluid evolved relative to 87sr 86sr from an initial pennsylvanian seawater signature to radiogenic values this evolution is due to increasing temperature and a concomitant evolution in pore water geochemistry in the dominantly silic clastic pennsylvanian section a possible source of mg for late stage dolomite is interpreted to be from the dissolution of early stage dolomite by reactive basinal fluids

the oldest handaxes in europe fact or artefact abstract hominin presence is well documented in a number of early pleistocene and early middle pleistocene european localities however the evidence currently available indicates that acheulean handaxes spread in the fluvial basins of western europe during mis 11 400 kyr ago associated with homo heidelbergensis although a number of early middle pleistocene acheulean assemblages have been dated from mis 16 onwards for this reason the magnetostratigraphic dating in southeast spain of two archaeological localities the open air site of solana del zamborino sz and the rock shelter site of cueva negra del estrecho del quipar eq that put back the appearance of handaxes to the early middle pleistocene limit scott and gibert 2009 is of particular interest as the new ages suggest that h heidelbergensis was a contemporary of h antecessor that had the ability to produce levallois debitage and to control fire during the early middle pleistocene transition however we have detected a number of errors in the interpretation of the archaeological assemblage from the first site as well as striking discrepancies with the original faunal lists published for both localities with several large mammal species that are omitted or arbitrarily changed to make the assemblages consistent with the new ages deduced from magnetostratigraphy for this reason we suggest that 1 the finding of reverse polarity in the sediments sampled for paleomagnetism in sz may simply record one of the polarity reversals that took place during the brunhes chron although the use by scott and gibert 2009 of a composite stratigraphic column precludes correlating these levels with a specific reversal and 2 the fauna and tools of eq correspond to the late middle pleistocene sedimentary infillings of this karst site while the samples taken for paleomagnetism belong to a previous sedimentary cycle during the matuyama chron such interpretations would be in better agreement with the age estimates provided by biostratigraphy and also with the currently accepted chronology for the appearance of acheulean industries in western europe

early holocene vegetation in the ayllon massif central system range spain based on macroremains a paleoecological approach abstract we present a palaeoecological study of well preserved vegetal macroremains in spain which age range 10 025 5371 cal yr bp confers it an outstanding interest because for the first half of the holocene palaeobotanical data are extremely scarce in the iberian central system range we found for the first time in the easternmost zone of the central system range macroremains belonging to the genus pinus these have specifically been identified as pinus cf sylvestris and pinus gr sylvestris these findings provide valuable information on the role of the genus pinus regarding the natural character of these pine forests in this relatively unknown region in the larger wood samples we measured tree rings and cross dated growth series which represent a 75 increase in the number of floating fossil chronologies and increase the time span by almost 1750 years in the centre of the iberian peninsula remarkably this is the first time in spain and in southern europe that some of the floating chronologies have been successfully crossdated creating four composite chronologies furthermore we discuss some palaeoclimatic inferences comparing with different sites in southern europe and provide new data for best knowing the palaeoecological characteristics of the first half of the holocene in spain likewise we found two bones belonging to aurochs bos primigenius one of these also dating from the first half of the holocene with valdojos constituting the only site with this taxon for this period in the central system range and surrounding areas

the olduvai buffalo pelorovis and the origin of bos the origin of the genus bos is a debated issue from 0 5 ma until historic times the genus is well known in the eurasian large mammal assemblages where it is represented by bos primigenius this species has a highly derived cranial anatomy that shows important morphological differences from other plio pleistocene eurasian genera of the tribe bovini such as leptobos bison proamphibos hemibos and bubalus the oldest clear evidence of bos is the skull fragment asb 198 1 from the middle pleistocene 0 6 0 8 ma site of asbole lower awash valley ethiopia the first appearance of bos in europe is at the site of venosa notarchirico italy 0 5 0 6 ma although the origin of bos has traditionally been connected with leptobos and bison after a detailed anatomical and morphometric study we propose here a different origin connecting the middle pleistocene eurasian forms of b primigenius with the african late pliocene and early pleistocene large size member of the tribe bovini pelorovis sensu stricto the dispersal of the bos lineage in western europe during middle pleistocene times seems to coincide with the arrival of the acheulean tool technology in this continent 2007 university of washington all rights reserved

the early middle pleistocene archeopaleontological site of wadi sarrat tunisia and the earliest record of bos primigenius abstract here we describe the new rich lacustrine paleontological and archeological site of wadi sarrat le kef northeastern tunisia dated to the beginning of the middle pleistocene 0 7 ma by a combination of paleomagnetism and biochronology this locality preserves the earliest record of auroch bos primigenius the ancestor of the worldwide extant domestic cattle species bos taurus which is represented by a nearly complete giant sized cranium specimen os1 both the cranial anatomy and the size of this specimen reflect the phylogenetic legacy inherited from its ancestor the late early pleistocene african bos buiaensis recorded in the eastern african paleoanthropological site of buia eritrea 1 0 ma given that the latter species is an evolved form of the classical early pleistocene african buffalo pelorovis oldowayensis the finding of b primigenius at wadi sarrat shows that the genus bos evolved in africa and dispersed into eurasia at the beginning of the middle pleistocene which coincides with the spread of the acheulian technocomplex in northern africa and europe therefore the lineage of pelorovis bos has been part of the human ecological landscape since the appearance of the genus homo in the african early pleistocene

chronostratigraphic constraints on middle pleistocene faunal assemblages and acheulian industries from the cretone lacustrine basin central italy integrated 40ar 39ar trace element stratigraphic palaeontological and palaethnological data provide geochronological and biochronological constraints for the sedimentary and tectonic history of a middle pleistocene fluvial lacustrine basin near rome cretone basin central italy which has yielded a significant record of mammal fossil remains and palaeolithic industry this work is a case study of the interplay between tectonics and glacio eustacy which strongly influenced the evolution of the tyrrhenian sea margin of central italy dating of tephra layers interbedded within the cretone basin lacustrine succession and reconstruction of relict terraced surfaces allow correlation with similar geochronologically constrained marine isotopic stages mis 15 5 terraced deposits along the coast coupled extensional tectonics and regional uplift over the last 600 ka caused the progressive uplifting and westward migration of the main fluvial lacustrine basin and the formation of a smaller satellite basin at its eastern margin here stable environmental conditions during mis 13 5 indicated continuous human and large mammal frequentation as testified by lithic industry and fossil remains ascribable to the acheulean and later early middle palaeolithic technocomplexes and galerian aurelian mammal faunas respectively in addition to providing independent age constraints to glacial sea level oscillations of this region the reconstructed chronostratigraphic setting for the cretone basin provides evidence for one of the oldest acheulean lithic assemblage of central italy as well as new biochronological and palaeobiogeographical data for some middle pleistocene mammal species of italy

application of new seismic attributes to collapse chimneys in the fort worth basin three dimensional seismic volumes from the central fort worth basin display roughly circular collapse chimneys that extend vertically about 800 m from the ordovician ellenburger formation to the atokan middle pennsylvanian caddo limestone collapse chimneys in carbonates may be caused by subaerial karst hydrothermal or tectonic extensional processes we use 3d multitrace geometric attributes including coherence volumetric curvature and energy weighted coherent amplitude gradients to investigate details of the origin of these structures the ordovician ellenburger surface resembles a subaerial karst landscape of cockpits dolines and frying pan valleys while resistivity based wireline image logs record 50 m of karst breccia facies however images from coherence and long wavelength most positive and most negative curvature volumes show many of the 800 m collapse features are associated with basement faults or with subtle pennsylvanian and younger tectonic features rather than with intra ellenburg

biostratigraphic and aminostratigraphic constraints on the age of the middle pleistocene glacial succession in north norfolk uk considerable debate surrounds the age of the middle pleistocene glacial succession in east anglia following some recent stratigraphical reinterpretations resolution of the stratigraphy here is important since it not only concerns the glacial history of the region but also has a bearing on our understanding of the earliest human occupation of north western europe the orthodox consensus that all the tills were emplaced during the anglian marine isotope stage mis 12 has recently been challenged by a view assigning each major till to a different glacial stage before during and after mis 12 between trimingham and sidestrand on the north norfolk coast datable organic sediments occur immediately below and above the glacial succession the oldest glacial deposit happisburgh till directly overlies the sidestrand unio bed here defined as the sidestrand hall member of the cromer forest bed formation dating of these sediments therefore has a bearing on the maximum age of the glacial sequence this paper reviews the palaeobotany and describes the faunal assemblages recovered from the sidestrand unio bed which accumulated in a fluvial environment in a fully temperate climate with regional deciduous woodland there are indications from the ostracods for weakly brackish conditions significant differences are apparent between the sidestrand assemblages and those from west runton the type site of the cromerian stage these differences do not result from contrasting facies or taphonomy but reflect warmer palaeotemperatures at sidestrand and a much younger age this conclusion is suggested by the higher proportion of thermophiles at sidestrand and the occurrence of a water vole with unrooted molars arvicola rather than its ancestor mimomyssavini with rooted molars amino acid racemisation data also indicate that sidestrand is significantly younger than west runton these data further highlight the stratigraphical complexity of the cromerian complex and support the conventional view that the happisburgh till was emplaced during the anglian rather than the recently advanced view that it dates from mis 16 moreover new evidence from the trimingham lake bed sidestrand cliff formation above the youngest glacial outwash sediments briton s lane formation indicates that they also accumulated during a middle pleistocene interglacial probably mis 11 all of this evidence is consistent with a short chronology placing the glacial deposits within mis 12 rather than invoking multiple episodes of glaciation envisaged in the new glacial stratigraphy during mis 16 12 10 and 6 copyright 2009 john wiley sons ltd

reevaluation of thermal maturity and stages of petroleum formation of the mississippian barnett shale fort worth basin texas new data including measured reflectance ro programmed open system pyrolysis data and kerogen elemental analyses obtained on the mississippian barnett shale in the fort worth basin texas indicate that secondary gas generation starts at 1 5 ro and not at the previously prescribed 1 1 ro oil cracking kinetic parameters derived from pyrolysis experiments in the presence and absence of water indicate that secondary gas generation will not occur at a thermal maturity as low as 1 1 ro and requires a minimum thermal maturity of 1 5 ro this difference is especially important in using the barnett shale as an analog for evaluating other possible shale gas plays the new reflectance measurements have a good relationship with hydrogen indices his and compare well with other published data sets however the relationship does not compare well with the previously published data used to prescribe 1 1 ro as the start of secondary gas generation in the barnett shale this discrepancy is attributed to differences in measured ro values and not attributed to differences in the hi values lack of publicly available information on the previously reported ro values makes it difficult to ascertain the reason for their lower values these lower ro values also have impact on the previously prescribed relationship for estimating ro from the temperature at maximum yield by programmed open system pyrolysis tmax as a result the new data do not agree with a previously described relationship and the considerable scatter makes the new relationship unreliable however the relationship between the hi and ro has less scatter which indicates that hi offers a better proxy in calculating ro than tmax for the barnett shale comparison of various programmed open system pyrolysis methods i e rock eval ii rock eval 6 source rock analyzer and hawk indicates that variations in hi are within 10 of one another an hi of at least 44 mg g total organic carbon is prescribed as a more certain limit for the start of secondary gas generation and prospective in situ gas shale accumulations

pleistocene environments and human presence in the middle atbara valley khashm el girba eastern sudan abstract a 50 m thick pleistocene fluvial succession is extensively exposed in the karib badlands area along the atbara river from khashm el girba to halfa al jadida through a widespread major unconformity this succession has been subdivided into the butana bridge synthem bbs and khashm el girba synthem kgs in the latter minor unconformities mark the boundaries between kgs1 kgs2 and kgs3 subsynthems the bbs is 10 m thick starts with braided stream gravel and terminates with high sinuosity river sand an intermediate silty interval with a well developed calcrete marks a period of reduced clastic input and morphological stability the bbs yielded vertebrate remains and many acheulean artefacts and was deposited from the late early pleistocene to the early middle pleistocene after a gap of some hundred thousand years the sedimentary record continues with 40 m thick kgs fluvial deposits they are quite diversified and include sands from meandering rivers kgs1 abruptly interrupted by braided river deposits that evolve to sinuous river sands kgs2 and finally from braided river pebbly sands to sheet flows kgs3 the kgs yielded abundant vertebrate remains and late acheulean to middle stone age artefacts mollusc patch reefs with stromatolitic coatings at the base of the kgs2 and kgs3 gave u th ages of 126 1 kyr 1 0 kyr and 92 2 kyr 0 7 kyr respectively these datings together with fossil assemblages and artefacts indicate a late middle pleistocene to late pleistocene age for the kgs the entire succession makes a northward goz regeb area transition into fluvio lacustrine deposits related to the atbara palaeolake through palaeohydrological analyses bankfull discharges have been estimated in some kgs1 and kgs2 fluvial channels they resulted into one order of magnitude less than the present day atbara river the variations in fluvial style and discharge were connected with climatic changes river network modifications induced by tectonics and palaeolake atbara level variations due to defined time constrains the climate changes recorded in the kgs are matched with the pleistocene marine isotope stages mis the kgs1 meandering rivers can be referred to the mis 7 wet period and the episodes of increasing rainfall in kgs2 and kgs3 to the eemian mis 5 5 and mis 5 3 followed by arid conditions mis 4 despite fossils and facies indicate environmental changes from arid savannah during the bbs to grassland with water pools during the kgs the atbara valley was always favourable to human settlement our study allowed to reconstruct although discontinuously the environments and the occurrence of human presence from the late early pleistocene to the holocene during this period hominins on their way from east africa to eurasia found abundant faunas and more or less perennial streams in the atbara valley

the bovid assemblage bovidae mammalia from the early pleistocene site of ubeidiya israel biochronological and paleoecological implications for the fossil and lithic bearing strata the site of ubeidiya provides a unique paleontological record in the early pleistocene of the levantine corridor with a rich faunal assemblage as well as evidence for the presence of early hominins this research presents a revision of the bovid record of the site found in the last seasons of excavations 1989e1999 as well as the previously published material five species of bovids have been identified bos oldowayensis bovini gen et sp indet cf bison sp oryx sp antelopini gen et sp indet cf pontoceros ambiguus spirocerus sp and gazella sp cf gazella gazella the paleoecological reconstruction of the site based on the bovid assemblages supported a non homologous ecology not similar to any african environment today this bovid assemblage is biochronologically compatible with previous ages proposed for the site based on the paleomagnetism and the carnivore guild around 1 6e1 2 ma

hominin multiple occupations in the early and middle pleistocene sequence of vallparadis barcelona spain abstract the archaeological site at vallparadis barcelona spain contains a continuous archaeostratigraphic sequence that extends from the upper limit of the jaramillo subchron 0 98 ma to the first half of the middle pleistocene c 0 6 ma evidence of human occupation lithic tools and cut marks has been identified in this sequence in the levels with reverse polarity from the early pleistocene evt7 4 and in the levels with normal polarity from the middle pleistocene evt3 2 in contrast to unit evt7 which was excavated using an extensive archaeological methodology the other levels were a rescue excavation the latter yielded a reduced lithic assemblage providing evidence of a multiple occupation sequence by hominins at vallparadis this evidence call into question the proposal that there was a gap in the hominin settlement before the appearance of mode 2 technology in europe a hypothesis that is based on stratigraphic sequences such as gran dolina atapuerca spain and the mid loire region massif central france regarding the early pleistocene lithic tools from unit evt7 at vallparadis the upper phase of the sequence evt4 2 shows longer chaines operatoires an increase in size of the lithic artefacts and the selection of better quality raw materials which in turn indicate changes in the source areas from which they were selected

early and middle pleistocene faunal and hominins dispersals through southwestern asia abstract this review summarizes the paleoecology of the early and middle pleistocene of southwestern asia based on both flora and fauna retrieved from a series of windows provided by the excavated sites the incomplete chrono stratigraphy of this vast region does not allow to accept the direct chronological correlation between the available sites and events of faunal and hominin dispersals from africa it also demonstrates that hominins survived in a mixed landscape of open parkland with forested surrounding hills in addition the prevailing environmental conditions are not sufficient to explain successful adaptations to new ecological niches away from the african savanna of the bearers of core and flake and the acheulian industries the differences in knapping and secondary shaping of stone artifacts probably reflect the learned traditions of different groups of hominins the current distribution of lithic industries across eurasia is undoubtedly incomplete due to lack of cultural continuities as well as paucity of field research in several sub regions this observation supports the contention that what we view as a constant stream of migrants was actually interrupted many times the continuous occupation of southwestern asia by the makers of the acheulian is in contrast with neighboring regions such as the iranian plateau and eastern europe a more complex model is required to explain the recorded eurasian archaeological cultural mosaic

analog models of restraining stepovers in strike slip fault systems scaled sandbox models have successfully simulated the geometries and progressive evolution of antiformal pop up structures developed in a weak sedimentary cover above restraining stepovers in offset sinistral strike slip fault systems in rigid basement models were run both with and without synkinematic sedimentation which was added incrementally to cover the growing antiformal structures vertical and horizontal sections of the completed models permit the full three dimensional 3 d structure of the pop ups to be analyzed in detail three representative end member experiments are described 30 underlapping restraining stepovers 90 neutral restraining stepovers and 150 overlapping restraining stepovers the experimental pop ups are typically sigmoidal to lozenge shaped antiformal structures having geometries that are dependent on both the stepover angle and stepover width in the underlying basement faults underlapping restraining stepovers typically form elongate lozenge shaped pop ups 90 neutral restraining stepovers produce shorter squat rhomboidal pop ups and overlapping restraining stepovers produce sigmoidal antiformal pop ups trans pop up cross fault systems are characteristic at large displacements on the basement fault system above the offset principal displacement zones the pop ups are commonly small narrow positive flower structures whereas in the stepover region they widen out and become markedly asymmetric this pop up asymmetry switches across the center of the stepover where the pop ups are largely symmetical maximum rotations measured within the central highly uplifted region of the pop ups increase from 7 counterclockwise for the underlapping 30 stepovers to 14 counterclockwise for the neutral 90 stepovers to 16 counterclockwise for the overlapping 150 stepovers in models where no synkinematic sediments were added during deformation the pop up structures are bound by convex flattening upward oblique slip reverse fault systems that link downward to the offsets in the basement fault system in contrast in the begin page 234 experiments where synkinematic sediments were added incrementally during deformation the pop ups are formed by oblique slip reverse faults that steepen upward into the synkinematic strata with the formation of fault propagation growth folds the analog models are compared with natural examples of pop up structures and show strong similarities in structural geometries and stratal architectures these models may provide structural templates for seismic interpretation of complex contractional structures in offset strike slip fault systems

quantifying the origin and geometry of circular sag structures in northern fort worth basin texas paleocave collapse pull apart fault systems or hydrothermal alteration three dimensional seismic data reveal numerous subcircular sag structures in the northern fort worth basin the structures are defined by concentric faults that extend vertically upward 760 1060 m 2500 3500 ft from the lower ordovician ellenburger group the largest structures remained active into the lower desmoinesian strawn group criteria are outlined for defining seismically resolvable sag structures and a detailed quantitative analysis of the geometries of these circular features was undertaken results are compared and contrasted with reviews of subsurface collapse mechanisms and strike slip processes that are known to produce subsurface circular to subcircular sag geometries in plan view in this manner we develop several constraints for differentiating collapse related sag structures from strike slip related sag structures qualitative analyses indicate that the geometries observed are strongly analogous to subsurface collapse features where material is removed at depth to create a void into which the overburden subsequently sags and collapses quantitative analyses support the formation of these features by incremental collapse and suprastratal deformation above a linked system of coalesced collapsed paleocaves within the ellenburger group observations and criteria presented herein provide valuable information in defining seismically resolvable collapse features worldwide and help distinguish sag features of collapse affinity from those of other origins

bison bonasus skull from the bihor mountains romania isotopic and morphological investigations in this study we investigated morphologically and geochemically a skull from an open pit situated on the c lineasa esu g rzii plateau bihor mountains the study presents the first 14c dating and stable isotope composition of bison skeletal remains from the romanian carpathians the result of 14c determination yielded two relevant maxima one is around ad 1550 and the second around ad 1645 the data indicate that the investigated bison died during the little ice age lia approximately 200 years before the last ones were hunted to extinction stable isotope composition of carbon from bison tooth enamel suggests that the bison diet consisted mainly of c3 grasses compatible with a high altitude habitat vegetation distribution and low mobility oxygen isotope composition of both phosphate and carbonate groups of tooth enamel indicates that the bison drank from stagnant water sources such as lakes or puddles formed from rain water this further suggests low mobility of the bison as well as the presen

a taxonomic and taphonomic study of pleistocene fossil deposits from the western nefud desert saudi arabia over the past decade a growing interest has developed on the archaeology palaeontology and palaeoenvironments of the arabian peninsula it is now clear that hominins repeatedly dispersed into arabia notably during pluvial interglacial periods when much of the peninsula was characterised by a semiarid grassland environment during the intervening glacial phases however grasslands were replaced with arid and hyperarid deserts these millennial scale climatic fluctuations have subjected bones and fossils to a dramatic suite of environmental conditions affecting their fossilisation and preservation yet as relatively few palaeontological assemblages have been reported from the pleistocene of arabia our understanding of the preservational pathways that skeletal elements can take in these types of environments is lacking here we report the first widespread taxonomic and taphonomic assessment of arabian fossil deposits novel fossil fauna are described and overall the fauna are consistent with a well watered semiarid grassland environment likewise the taphonomic results suggest that bones were deposited under more humid conditions than present in the region today however fossils often exhibit significant attrition obscuring and fragmenting most finds these are likely tied to wind abrasion insolation and salt weathering following fossilisation and exhumation processes particularly prevalent in desert environments

analysis of the cleburne texas earthquake sequence from june 2009 to june 2010 on 9 june 2009 an graphic 1 2 8 earthquake shook cleburne texas a community not known to have previously experienced earthquakes over 50 small earthquakes followed by the end of december 2009 a temporary network of four and then five iris passcal broadband systems was deployed from june 2009 to june 2010 recording data that were used to locate 38 events with the most confident p and s arrival picks event locations were distributed along a 2 km long north northeast trend the location centroid was at 32 298 n 97 372 w and at 3 6 km depth this location is approximately 1 3 km from a saltwater disposal well that began injection in october 2007 and 3 2 km away from a second injection well that was active from september 2005 to late july 2009 focal mechanisms estimated for the best recorded events suggest a north northeast south southwest trending normal fault with a dip of 50 and a component of oblique motion rake of 80 this average solution is generally consistent with the north northeast trending extensional faults that are prevalent across parts of texas oklahoma louisiana and arkansas stress drops calculated from p and s spectra for seven different events ranged from 3 9 to 90 bars with most estimates between 40 and 50 bars typical values for intraplate earthquakes because there were no known previous earthquakes and the located events were close to the two injection wells and near the injection depth the possibility exists that earthquakes may be related to fluid injection online material tables of absolute and relative earthquake locations and a figure summarizing focal mechanism solutions 1 embed inline graphic 1 gif

visualization and characterization of structural deformation fabric and velocity anisotropy fractures develop with different intensity and preferred orientations in response to changing stress regimes throughout geologic time fractures with preferred orientations are often interpreted as the cause of seismic p wave velocity vp anisotropy as well as linear features seen in seismic attribute volumes field experiments show that stress orientation can often be directly measured by p wave anisotropy while the lineaments seen in the volumetric curvature attributes are related to deformation

mississippian barnett shale fort worth basin north central texas gas shale play with multi trillion cubic foot potential the mississippian barnett shale serves as source seal and reservoir to a world class unconventional natural gas accumulation in the fort worth basin of north central texas the formation is a lithologically complex interval of low permeability that requires artificial stimulation to produce at present production is mainly confined to a limited portion of the northern basin where the barnett shale is relatively thick 300 ft 92 m organic rich presentday total organic carbon 3 0 thermally mature vitrinite reflectance 1 1 and enclosed by dense limestone units able to contain induced fractures the most actively drilled area is newark east field currently the largest gas field in texas newark east is 400 mi 2 1036 km 2 in extent with more than 2340 producing wells and about 2 7 tcf of booked gas reserves cumulative gas production from barnett shale wells through 2003 was about 0 8 tcf wells in newark east field typically produce from depths of 7500 ft 2285 m at rates ranging from 0 5 to more than 4 mmcf day estimated ultimate recoveries per well range from 0 75 to as high as 7 0 bcf efforts to extend the current barnett play beyond the field limits have encountered several challenges including westward and northward increases in oil saturation and the absence of lithologic barriers to induced fracture growth patterns of oil and gas occurrence in the barnett in conjunction with maturation and burial history data indicate a complex multiphased thermal evolution with episodic expulsion of hydrocarbons and secondary cracking of primary oils to gas

3 d seismic evidence of the effects of carbonate karst collapse on overlying clastic stratigraphy and reservoir compartmentalization a multidisciplinary team composed of stratigraphers petrophysicists reservoir engineers and geophysicists studied a portion of boonsville gas field in the fort worth basin of north central texas to determine how modern geophysical geological and engineering techniques can be combined to understand the mechanisms by which fluvio deltaic depositional processes create reservoir compartmentalization in a low to moderate accommodation basin an extensive database involving well logs cores production and pressure data from more than 200 wells 26mi2 67km2 of 3 d seismic data vertical seismic profiles vsps and checkshots was assembled to support this investigation we found the most important geologic influence on stratigraphy and reservoir compartmentalization in this basin to be the existence of numerous karst collapse chimneys over the 26 mi2 67km2 area covered by the 3 d seismic grid these near vertical karst collapses originated in or near the deep ordovician age ellenburger carbonate

3d volumetric multispectral estimates of reflector curvature and rotation one of the most accepted geologic models is the relation between reflector curvature and the presence of open and closed fractures such fractures as well as other small discontinuities are relatively small and below the imaging rangeofconventionalseismicdata dependingonthetectonic regime structural geologists link open fractures to either gaussian curvature or to curvature in the dip or strike directions reflector curvature is fractal in nature with different tectonic and lithologic effects being illuminated at the 50 m and1000 m scales untilnow suchcurvatureestimateshave been limited to the analysis of picked horizons we have developed what we feel to be the first volumetric spectral estimates of reflector curvature we find that the most positive and negative curvatures are the most valuable in the conventional mapping of lineations including faults folds and flexures curvatureismathematicallyindependentof andinterpretatively complementary to the well established coherence geometric attribute we find the long spectral wavelengthcurvatureestimatestobeofparticularvalueinextracting subtle broad features in the seismic data such as folds flexures collapse features fault drags and under and overmigrated fault terminations we illustrate the value of these spectral curvature estimates and compare them to other attributes through application to two land data sets a salt domefromtheonshorelouisianagulfcoastandafractured karsteddatavolumefromfortworthbasinofnorthtexas

lineament preserving filtering recently developed seismic attributes such as volumetric curvature and amplitude gradients enhance our ability to detect lineaments however because these attributes are based on derivatives of either dip and azimuth or the seismic data themselves they can also enhance high frequency noise recently published structure oriented filtering algorithms show that noise in seismic data can be removed along reflectors while preserving major structural and stratigraphic discontinuities in one implementation the smoothing process tries to select the most homogenous window from a suite of candidate windows containing the analysis point a second implementation damps the smoothing operation if a discontinuity is detected unfortunately neither of these algorithms preserves thin or small lineaments that are only one voxel in width to overcome this defect we evaluate a suite of nonlinear feature preserving filters developed in the image processing and synthetic aperture radar sar world and apply them to both synthetic and real 3d dip and azimuth volumes of fractured geology from the forth worth basin usa we find that the multistage median based modified trimmed mean algorithm preserves narrow geologically significant features of interest while suppressing random noise and acquisition footprint

comment on reassessing the sedimentary deposits and vertebrate assemblages from ponte galeria area rome central italy an archive for the middle pleistocene faunas of europe by f marra l pandolfi c petronio g di stefano m gaeta and l salari earth science reviews 139 2014 104 122 abstract recently marra et al 2014 published an articulate revision on the pleistocene sedimentary sequences and vertebrate assemblages from the ponte galeria area roma italy however in our opinion some important palaeontological data are missing or incorrectly reported the aim of this comment is to provide crucial elements and put in evidence the shortcomings to the study of this classical palaeontological site

three dimensional architecture of a coalesced collapsed paleocave system in the lower ordovician ellenburger group central texas the three dimensional interwell scale architecture of a lower ordovician ellenburger coalesced collapsed paleocave system was constructed through the integration of ground penetrating radar gpr shallow core and outcrop data the data were collected near marble falls in central texas over an area 800 1000 m 2600 3300 ft that could cover several oil well locations 160 ac 0 65 km2 typical of a region such as west texas integration of core based facies descriptions with gpr reflection response identified several paleocave facies that can be recognized and mapped with gpr data alone 1 continuous reflections image the undisturbed strata 2 relatively continuous reflections over tens of meters characterized by faults and folds image the disturbed strata and 3 chaotic reflections having little to no perceptible continuity image heterogeneous cave related brecciated facies recognized in core that cannot be individually resolved with the gpr data these latter facies include the highly disturbed strata coarse clast chaotic breccia fine clast chaotic breccia and sediment fill the three dimensional architecture of the coalesced collapsed paleocave system based on core and gpr data indicates that there are trends of brecciated bodies that are as much as 350 m 1100 ft wide greater than 1000 m 3300 ft long and tens of meters high these brecciated bodies are coalesced collapsed paleocaves between the brecciated bodies are areas of disturbed and undisturbed host rock that are jointly as much as 200 m 660 ft wide as a cave system is buried many structural features form by mechanical compaction these features include folds sags and faults the folds and sags measure from a few meters to several hundred meters wide the collapse related faults are numerous and can have several meters of displacement most are normal faults but reverse faults also occur

robust estimates of 3d reflector dip and azimuth much of seismic stratigraphy is based on the morphology of seismic textures the identification of reflector terminations and subtle changes in dip and azimuth allows us to infer coherent progradational and transgressive packages as well as more chaotic slumps fans and braided stream complexes infill of karsted terrains gas seeps and of course faults and angular unconformities a major difficulty in estimating reflector dip and azimuth arises at discrete lateral and vertical discontinuities across which reflector dip and azimuth change the smearing across these boundaries produced by traditional dip and azimuth estimations is avoided by using temporally and spatially shifted multiple windows that contain each analysis point this more robust estimation of dip and azimuth leads to increased resolution of well established algorithms such as coherence coherent amplitude gradients and structurally oriented filtering more promising still is the analysis of high resolution dip and azimuth through vol

late paleozoic subsidence and burial history of the fort worth basin abstract the fort worth basin in northcentral texas is a major shale gas producer yet its subsidence history and relationship to the ouachita fold thrust belt have not been well understood we studied the depositional patterns of the basin during the late paleozoic by correlating well logs and constructing structure and isopach maps we then modeled the one dimensional 1 d and two dimensional subsidence history of the basin and constrained its relationship to the ouachita orogen because the super middle pennsylvanian strata were largely eroded in the region adding uncertainty to the subsidence reconstruction we used petromod 1 d to conduct thermal maturation modeling to constrain the post middle pennsylvanian burial and exhumation history by matching the modeled vitrinite reflectance with measured vitrinite reflectance along five depth profiles our results of depositional patterns show that the tectonic uplift of the muenster uplift to the northeast of the basin influenced subsidence as early as the middle mississippian and the ouachita orogen became the primary tectonic load by the late middle pennsylvanian when the depocenter shifted to the east our results show that the basin experienced 3 7 5 2 km 12 100 17 100 ft of burial during the pennsylvanian and the burial depth deepens toward the east we attributed the causes of deep pennsylvanian burial and its spatial variation to flexural subsidence that continued into the late pennsylvanian in response to the growth of the ouachita orogen and southeastward suturing of laurentia and gondwana the modeling results also suggest that the mississippian barnett shale reached the gas maturation window during the middle late pennsylvanian

reassessing the sedimentary deposits and vertebrate assemblages from ponte galeria area rome central italy an archive for the middle pleistocene faunas of europe abstract the ponte galeria area is part of the larger campagna romana and hosted the inner delta of the tiber river since the beginning of the middle pleistocene allowing the deposition of a series of glacio eustatically controlled fluvial lacustrine sedimentary successions very rich in fossil mammal remains due to its richness of fossiliferous sites this area represents an exceptional archive for the study and understanding of the biochronological paleobiogeographical and paleoenvironmental evolution during the middle pleistocene in europe a series of recent studies using the 40 ar 39 ar ages of tephra intercalated within the sedimentary deposits provided a large amount of geochronological data linking these aggradational successions to the different marine isotopic stages in the present paper we present a complete review of the faunal assemblages identified so far in the ponte galeria area and we constrain the ages of the faunal units by placing them within the new chronostratigraphic scheme by means of this interdisciplinary approach we re calibrate the mammal assemblages collected in this area and reconstruct a new biochronological and paleobiogeographic framework for the italian peninsula during the middle pleistocene in particular we distinguish six well defined biochronological units slivia ponte galeria isernia fontana ranuccio torre in pietra and vitinia in the studied area covering a time span of ca 0 6 myr from the early to middle pleistocene transition to at least marine isotope stage 7 this period is characterized in europe by the mid pleistocene revolution global climate change and by the transition at first between villafranchian and galerian taxa and later between the galerian and aurelian ones according to the reviewed data the persistence of villafranchian taxa is recorded in italy at the beginning of the middle pleistocene probably due to favorable climatic conditions or delay in dispersal of competitive species while the faunal turnover between the villafranchian and galerian species was completed around 0 6 0 5 ma during this time bos primigenius and other temperate warm taxa were widespread in the peninsula earlier than in western europe in contrast typical aurelian taxa usually related with temperate cold climatic conditions ursus spelaeus megaloceros giganteus occurred later in italy than in other western european areas