a new geological map of the brabant massif belgium a new geological map mostly subcrop of the brabant massif is presented based on a revised lithostratigraphy of the outcrop area and on recently acquired palaeontological and lithological data from boreholes in the concealed area new interpretations of magnetic and gravity data are used to extend the lithostratigraphical units into areas with few or no boreholes a structural model of the western northern and southern parts of the brabant massif is presented the main anticlinal axis plunges towards the west northwest its core comprising upper precambrian to lower cambrian terrigenous rocks which outcrop in the southeast to the north of the main axis younger rocks appear in regular succession but to the southwest this picture is complicated by the occurrence of a second anticlinal structure and by a subparallel magmatic arc

multiscale interactions in the life cycle of a tropical cyclone simulated in a global cloud system resolving model part ii system scale and mesoscale processes abstract the life cycle of tropical storm isobel was simulated reasonably well in the nonhydrostatic icosahedral atmospheric model nicam a global cloud system resolving model the evolution of the large scale circulation and the storm scale structure change was discussed in part i both the mesoscale and system scale processes in the life cycle of the simulated isobel are documented in this paper in the preconditioned favorable environment over the java sea mesoscale convective vortices model mcvs developed in the mesoscale convective systems mcss and convective towers with cyclonic potential vorticity pv anomalies throughout the troposphere model vortical hot towers vhts appeared in the model mcvs multiple model vhts strengthened cyclonic pv in the interior of the model mcv and led to the formation of an upright monolithic pv core at the center of the concentric mcv primary vortex enhancement as the monolithic pv core with a warm core developed near the circulation center the intensif

genesis of tropical storm eugene 2005 from merging vortices associated with itcz breakdowns part i observational and modeling analyses abstract although tropical cyclogenesis occurs over all tropical warm ocean basins the eastern pacific appears to have the highest frequency of tropical cyclogenesis events per unit area in this study tropical cyclogenesis from merging mesoscale convective vortices mcvs associated with breakdowns of the intertropical convergence zone itcz is examined this is achieved through a case study of the processes leading to the genesis of tropical storm eugene 2005 over the eastern pacific using the national centers for environmental prediction reanalysis satellite data and 4 day multinested cloud resolving simulations with the weather research and forecast wrf model at the finest grid size of 1 33 km observational analyses reveal the initiations of two mcvs on the eastern ends of the itcz breakdowns that occurred more than 2 days and 1000 km apart the wrf model reproduces their different movements intensity and size changes and vortex vortex interaction at nearly the right timing and location at

genesis of hurricane julia 2010 within an african easterly wave developing and nondeveloping members from wrf letkf ensemble forecasts abstractin this study the predictability of and parametric differences in the genesis of hurricane julia 2010 are investigated using 20 mesoscale ensemble forecasts with the finest resolution of 1 km results show that the genesis of julia is highly predictable with all but two members undergoing genesis despite the high predictability substantial parametric differences exist between the stronger and weaker members notably the strongest developing member exhibits large upper tropospheric warming within a storm scale outflow during genesis in contrast the nondeveloping member has weak and more localized warming due to inhibited convective development and a lack of a storm scale outflow a reduction in the rossby radius of deformation in the strongest member aids in the accumulation of the warmth while little contraction takes place in the nondeveloping member the warming in the upper troposphere is responsible for the development of meso scale surface pressure falls and a meso surface low i

sediment slump structures a review of diagnostic criteria and application to an example from newfoundland abstract in the study of the history of deformed sedimentary rocks it is important that the cause of the deformation and the timing of deformation relative to metamorphic and tectonic events be assessed there is a continuous gradation between the deformation of freshly deposited sediments by gravitational forces and the deformation of well lithified sediments by tectonic forces so determining the degree to which gravity tectonism and lithification influenced deformation can be very difficult the characteristics that may be considered in determining the origin of deformational structures in sedimentary rocks can be divided into five categories ductile deformation structures 1 can provide definitive criteria for recognizing post lithification deformation but not pre lithification deformation this also holds for 2 brittle deformation structures and decollements overprinting of sediment reworking or remobilization structures 3 are the best criteria for recognizing pre lithification structures fabrics 4 can be very useful but are as yet poorly understood and there are misconceptions in the literature about what sort of fabrics are or are not found in unlithified sediments spatial relationships 5 may also tell us a great deal but are most useful when taken in conjunction with other types of evidence complex fold patterns in sandstones on farmer head north central newfoundland provide a case study for criteria that may be used to determine the degree of lithification during deformation although these folds have been interpreted as slump folds by earlier workers fabrics and spatial relationships point to a tectonic post lithification origin for the structures a conclusion which has significant implications for the interpretation of the regional geology

interpreting fold and fault geometries from within the lateral to oblique parts of slumps a case study from the anglo brabant deformation belt belgium abstract using a rigorous comparison of as many slump fold based and slump related fault based methods as possible also small complex data sets can be used to deduce a reliable slump transport direction and sense this is exemplified using late early ordovician to middle ordovician slump features of the anglo brabant deformation belt the suggested procedure involves a an analysis of fold data by means of 1 the mean axis method 2 the separation arc method 3 the axial planar intersection method 4 the fold hinge azimuth and interlimb angle method 5 the fold axial surface strike and interlimb angle method and 6 the axial surface dip and dip direction method b an analysis of slump related fault data by means of 1 the mean fault orientation method 2 the fault separation method 3 the fault intersection method and 4 the best fit girdle to fault poles method and finally c a rigorous comparison of the results of the different methods several possible diagnostic criteria are put forward for distinguishing slump deformation features trending at low angles to transport direction oblique to lateral parts of slump sheets or internal lobes or tongues and slump deformation features trending at high angles to transport direction frontal to central parts of slump sheets these criteria include the relationship between fold interlimb angle and axial surface dip the plunge of the fanning axis of the reverse slump related faults and the plunge of the intersection of the reverse and normal slump related faults such criteria greatly facilitate the interpretation of the often confusing results of many classical methods moreover the plunge azimuth of the intersection of the normal and reverse slump related faults and the mismatch between slump transport direction inferred from fold based and fault based methods may both be diagnostic for dextrally deformed or sinistrally deformed slump sheet parts

single layer buckle folding in non linear materials i experimental study of fold development from an isolated initial perturbation abstract scale model experiments involving pure shear compression of a single layer embedded in a weaker matrix were carried out to study the influence of a pre existing isolated perturbation in the shape of an otherwise planar layer on the location and shape of folds different grades of paraffin wax were used as analogues for rocks with power law rheology the wax used for the matrix flows in steady state with a stress exponent of about 3 8 the layer has a stress exponent of about 3 and strain softens viscosity ratios considered at yield stress for the layer and matrix of 30 1 and 8 1 were used bell shaped perturbations were introduced into the layer with initial average wavelengths of 8 16 and 32 times layer thickness and corresponding initial limb dips of 12 5 and 3 respectively the fold packet develops at the site of the introduced perturbation and spreads slowly along the layer with increasing shortening the shape of the initial perturbation strongly influences the fold geometry broader initial perturbations develop broader folds undergo more layer parallel shortening and develop a wider zone of contact strain the influence of the introduced perturbation shape is most marked when its average wavelength component is larger than the dominant wavelength i e the wavelength of maximum growth rate the degree of bonding between layer and matrix also influences fold development folds with welded layer matrix boundaries amplify much more slowly with a greater proportion of layer parallel shortening than folds where slip between layer and matrix is promoted

genesis of hurricane julia 2010 within an african easterly wave low level vortices and upper level warming abstractwhile a robust theoretical framework for tropical cyclogenesis tcg within african easterly waves aews has recently been developed little work explores the development of low level meso scale vortices llvs and a meso scale surface low in relation to deep convection and upper tropospheric warming in this study the development of an llv into hurricane julia 2010 is shown through a high resolution model simulation with the finest grid size of 1 km the results presented expand upon the connections between llvs and the aew presented in previous studies while demonstrating the importance of upper tropospheric warming for tcg it is found that the significant intensification phase of hurricane julia is triggered by the pronounced upper tropospheric warming associated with organized deep convection the warming is able to intensify and expand during tcg owing to formation of a storm scale outflow beyond the rossby radius of deformation results confirm previous ideas by demonstrating that th

timing of magmatism foreland basin development metamorphism and inversion in the anglo brabant fold belt new data implying crustal activation of eastern avalonia along the anglo brabant fold belt are presented late ordovician subduction related magmatism in east anglia and the brabant massif coupled with accelerated subsidence in the anglia basin and in the brabant massif during silurian time indicate a foreland basin development final collision resulted in folding cleavage development and thrusting during the mid lochkovian to mid eifelian in the southeast of the anglo brabant fold belt acadian deformation produced basin inversion and the regional antiformal structure of the brabant massif the uplift inferred from the sedimentology petrography and reworked palynomorphs in the lower devonian of the dinant synclinorium is confirmed by illite crystallinity studies the tectonic model discussed implies the presence of two subduction zones in the eastern part of eastern avalonia one along the anglo brabant fold belt and another under the north sea in the prolongation of the north german polish caledonides

genesis of tropical storm eugene 2005 from merging vortices associated with itcz breakdowns part ii roles of vortex merger and ambient potential vorticity abstract in this study the roles of merging midlevel mesoscale convective vortices mcvs and convectively generated potential vorticity pv patches embedded in the intertropical convergence zone itcz in determining tropical cyclogenesis are examined by calculating pv and absolute vorticity budgets with a cloud resolving simulation of tropical storm eugene 2005 results show that the vortex merger occurs as the gradual capture of small scale pv patches within a slow drifting mcv by another fast moving mcv thus concentrating high pv near the merger s circulation center with its peak amplitude located slightly above the melting level the merging phase is characterized by sharp increases in surface heat fluxes low level convergence latent heat release and upward motion lower tropospheric pv surface pressure falls and growth of cyclonic vorticity from the bottom upward melting and freezing appear to affect markedly the vertical structures of diabatic heating convergence absolute vorticity

large scale slumping deduced from structural and sedimentary features in the lower palaeozoic anglo brabant fold belt belgium distinguishing slump folds from tectonic folds in poorly exposed areas can be difficult especially when the scale of the slump folds exceeds outcrop scale in the southeastern part of the single phase deformed lower palaeozoic anglo brabant fold belt a comparison of cleavage fold relationships and stratigraphic polarity shows that a 200 m thick interval of middle caradoc fine grained turbidites in the core of a large synform was overturned prior to tectonic deformation this overturning is attributed to large scale slumping which was most likely a result of middle caradoc seismic activity the exposed portion of the large slump sheet contains only a few small slump folds and intraformational breccias making up less than 5 of the exposed thickness if the beds were not overturned large scale slumping would never be suspected and the small slump folds would probably be interpreted as localized features in an overall stable sedimentary pile this may explain why so few ancient large scale slides and slumps have been reported the small amount of internal deformation makes them very difficult to recognize especially when dealing with poorly exposed areas as such large ancient slides and slumps may be more common than suggested by the geological literature

genesis of typhoon chanchu 2006 from a westerly wind burst associated with the mjo part ii roles of deep convection in tropical transition abstractin this study the life cycles of a series of four major mesoscale convective systems mcss during genesis and their roles in transforming a vertically tilted vortex associated with a westerly wind burst hereafter the wwb vortex into typhoon chanchu 2006 are examined using 11 day cloud resolving simulations presented in part i it is found that the tilted wwb vortex at early stages is characterized by an elevated cold core layer about 200 hpa thick below and a weak warm column above with large vertical wind shear across the layer which extends over a horizontal distance of about 450 km between the vortex s 400 and 900 hpa centers during the final two days of the genesis process the upper level warm column increases in depth and intensity as a result of the absorption of convectively generated vortices cgvs including a mesoscale convective vortex mcv causing more rapid amplification of cyclonic vorticity in the middle than the lower troposphere the commencement of sustained intens

the role of initial perturbations in the development of folds in a rock analogue abstract a series of experiments is described in which layered specimens were shortened parallel to the layering the specimens comprise two salt nacl layers sandwiched between three layers of salt mica synthetic schist all specimens were prepared and deformed under the same conditions except for the amount of shortening which was varied the resulting fold shapes are variable even where the amounts of shortening are the same in one specimen folds are believed to have developed essentially by buckling with very little concomitant bulk homogeneous shortening perpendicular to the axial plane the specimen lacks an axial plane foliation other folds are believed to have experienced varying amounts of bulk homogeneous shortening before and during buckling and all have axial plane foliations that have developed by grain scale transposition of the original bedding parallel mica foliation the difference in the behaviour of the various specimens is explained in terms of initial perturbations these irregularities take the form of initial deflections in the almost planar bedding variation in the degree of preferred orientation of the mica grains and local compositional variation within individual salt mica layers

nomenclature and geometric classification of cleavage transected folds abstract terms and measures for describing real and theoretical three dimensional cleavage transected folds are reviewed and clarified the geometrically possible range of cleavage transected folds is explored reappraisal and extension of published measures allows study of geologically realistic asymmetrical folds scale related description of cleavages and associated folds is formalized and sampling problems discussed the plot comparing axial with profile plane fold transection by cleavage is used to classify transected folds in a geometrical manner it helps reveal the constitutive geometry of cleavage transected folds and should help identify the most actively growing fold order during a cleavage forming episode plotted examples from welsh asymmetric cleavage transected folds of acadian age show complex transection geometries

the effect of initial perturbation shape and symmetry on fold development abstract single layer fold experiments were carried out to study the influence of initial perturbation symmetry on the symmetry of folds developed using paraffin wax as a rock analogue under experimental conditions both matrix and layer have a power law rheology with an initial effective viscosity contrast of ca 17 1 the matrix flows in steady state with n 2 7 and the layer work softens with n eff 10 folds developed from an initially symmetric perturbation remain symmetric reflecting the pure shear plane strain boundary conditions folds developed from an initially asymmetric perturbation however show a progressive exaggeration of this asymmetry such that the introduced 3 5 difference in limb dip increases to 65 at 23 bulk shortening these experiments indicate that for low competence contrast between layer and matrix the geometry of initial perturbations of finite amplitude e g ripple marks channels half graben structures may be an important factor in determining the geometry and distribution of folds

influence of slump folds on tectonic folds an example from the lower ordovician of the anglo brabant deformation belt belgium although it is generally accepted that buckle folds will not develop in a perfectly planar layer without the presence of some irregularity or perturbation at which the folds initiate there are very few cases in which individual natural folds can be linked to specific irregularities within the lower ordovician abbaye de villers formation anglo brabant deformation belt metre scale tectonic folds occur of which the position and to a certain extent the geometry appear to be controlled by slump folds and related features the metre scale tectonic folds interpreted as parasitic structures on the limb of a large scale host fold occur only within a stratigraphic level affected by slumping in this level tectonic antiforms tend to form superimposed on antiformal slump folds and on zones of abrupt slump related thickness increase and tectonic synforms on synformal slump folds and on zones of abrupt thickness decrease the rather irregular 3d geometry of sedimentary sequences suggests that many more similar cases should exist in which folds can be linked to specific irregularities however possibly it is also this abundance of irregularities in sedimentary sequences in combination with fold and outcrop scale that makes it difficult to attribute a particular fold to a particular perturbation

arcuate fold and cleavage patterns in the southeastern part of the anglo brabant fold belt belgium tectonic implications abstract the brabant massif belgium is situated at the southeastern extremity of the anglo brabant fold belt the predominantly concealed eastern branch of the british belgian caledonides in contrast to the other parts of this caledonian slate belt the deformation history in the brabant massif has to date never been constrained properly in this paper a synthesis is presented of the structural observations in the limited outcrop area of the brabant massif in particular with respect to cleavage and fold trajectories and mutual cleavage fold relationships arcuate fold and cleavage patterns as well as the presence of cleavage transected folds are demonstrated similar to the other parts of the belt moreover the arcuate trajectories are considered to reflect the trace of the caledonian deformation front once obscured by the variscan ardenne allochthon combined with interpretations of the aeromagnetic and bouguer anomaly maps an overall kinematic model is proposed for the acadian deformation event in the brabant massif with the proposed model calling upon processes of indentation by promontories and lateral escape of lithostructural domains as well as on the control exerted by rigid granitoid basement blocks the strong similarities with the other parts of the british belgian caledonides become apparent by defining an overall shortening direction and proposing a trace for the caledonian deformation front in this southeastern extremity of the anglo brabant fold belt an integrated tectonic image is obtained for the entire british belgian caledonides

kinetic energy budget during the genesis period of tropical cyclone durian 2001 in the south china sea abstracta set of kinetic energy ke budget equations associated with four horizontal flow components was derived to study the ke characteristics during the genesis of tropical cyclone tc durian 2001 in the south china sea using numerical simulation data the genesis process was divided into three stages the monsoon trough stage stage 1 the midlevel mesoscale convective vortex mcv stage stage 2 and the establishment stage of the tc vortex stage 3 analysis showed that the ke of the symmetric rotational flow srf was the largest and kept increasing especially in stages 2 and 3 representing the symmetrization process during tc genesis the ke of the srf was mainly converted from the ke of the symmetric divergent flow sdf largely transformed from the available potential energy ape it was found that vortical hot towers vhts emerged abundantly aggregated and merged within the mcv region in stages 1 and 2 from the energy budget perspective massive moist convection produced latent h

oceanic cyclogenesis as induced by a mesoscale convective system moving offshore part ii genesis and thermodynamic transformation abstract the genesis of intense cyclonic vorticity in the boundary layer and the transformation of a low level cold pool to a warm core anomaly associated with the long lived mesoscale convective systems mcss which produced the july 1977 johnstown flash flood and later developed into a tropical storm are examined using a 90 h real data simulation of the evolution from a continental mcs vortex to an oceanic cyclone storm system it is shown that the midlevel vortex trough at the end of the continental mcs s life cycle is characterized by a warm anomaly above and a cold anomaly below the mesovortex as it drifts toward the warm gulf stream water plays an important role in initiating and organizing a new mcs and a cyclonic shear vorticity band at the southern periphery of the previously dissipated mcs it is found from the vorticity budget that the vorticity band is amplified through stretching of absolute vorticity as it is wrapped around in a slantwise manner toward the cyclone center then the as

large scale variscan shearing at the southeastern margin of the eastern rhenohercynian belt a reinterpretation of chaotic rock fabrics in the harz mountains germany for the past 50 years large parts of the harz mountains eastern rhenohercynian zone germany have been considered to consist of olistostromes of early carboniferous age which were later deformed by variscan tectonics the olistostrome model was associated with the assumption that sliding of coherent nappe units occurred contemporaneously with the submarine mass flow processes a sedimentary origin of olistostromes was derived mainly from the block in matrix fabric of the rocks assumed soft rock deformation fabrics and the composition and age of blocks based on available biostratigraphic data block composition and fabric studies of outcrops and drilling cores it can be shown that the fabric of chaotic rocks is mainly caused by variscan tectonic deformation at late carboniferous without any indication of soft rock deformation processes and structures indicating a tectonic origin are boudinage extensive cataclasis and transposition of folded rocks commonly associated with intense mineralization as well as the regular spatial distribution and orientation patterns of blocks the chaotic rock fabric mainly evolved in the brittle ductile transitional zone late to post kinematic relative to the synmetamorphic first cleavage widespread chaotic rocks are localized in the allochthonous domain which itself is characterized by generally strong tectonic rock deformation and thrust faulting our results suggest that significant mass flow deposits do not occur the previously proposed olistostromes are melanges and broken formations of tectonic origin which form a large scale network of anastomosing shear zones that penetrate and juxtapose more or less intact coherent rock units of different stratigraphy and provenance due to the tectonic origin the entire early paleozoic sequences may exhibit chaotic rock fabrics

nutrient inputs through submarine groundwater discharge in an embayment a radon investigation in daya bay china abstract daya bay a semi closed bay of the south china sea is famous for its aquaculture agriculture and tourism although routine environmental investigations in the bay have been conducted since the early 1980s evaluations of submarine groundwater discharge sgd an important process in exchange between groundwater and coastal seawater and its environmental impacts have never been reported in this study naturally occurring radon isotope 222 rn was measured continuously at two sites north west and middle east sites and used as a tracer to estimate sgd and associated nutrient inputs into the bay the sgd rates estimated based on the 222 rn mass balance model were on average 28 2 cm d at north west site and 30 9 cm d at middle east site the large sgd rate at middle east site may be due to the large tidal amplitude and the sandy component with high permeability in sediments the sgd driven nutrient fluxes which were calculated as the product of sgd flux and the difference of nutrient concentrations between coastal groundwater and seawater were 3 28 10 5 mol d for dissolved nitrates no 3 n 5 84 10 3 mol d for dissolved inorganic phosphorous dip and 8 97 10 5 mol d for reactive silicate si these nutrient inputs are comparable to or even higher than those supplied by local rivers in addition these sgd driven nutrients have a nitrogen phosphorous ratio as high as 43 which may significantly affect the ecology of coastal waters and lead to frequent occurrence of harmful algal blooms

numerical simulations of the genesis of hurricane diana 1984 part i control simulation abstract the complete transformation of a weak baroclinic disturbance into hurricane diana is reproduced by numerical simulations using the fifth generation pennsylvania state university national center for atmospheric research mesoscale model three distinct phases of the evolution are evident first baroclinic and barotropic development strongly modified by the effects of latent heating occurs during the latter part of this phase the low level circulation is strengthened through the axisymmetrization of remote potential vorticity anomalies that are generated by condensational heating and then advected toward the incipient storm the axisymmetrization process evinces properties of both nonlinear discrete vortex merger and vortex rossby wave dynamics the transformation from cold core to warm core vortex occurs in this development stage in the second phase lasting 10 12 h little deepening occurs spiral bands of convection begin to form and the core of the storm moistens eventually reaching 95

genesis of typhoon nari 2001 from a mesoscale convective system 1 in this study the origin and genesis of typhoon nari 2001 as well as its erratic looping track are examined using large scale analysis satellite observations and a 4 day nested cloud resolving simulation with the finest grid size of 1 33 km observational analysis reveals that nari could be traced 5 days back to a diurnally varying mesoscale convective system with growing cyclonic vorticity and relative humidity in the lower troposphere and that it evolved from a mesoscale convective vortex mcv as moving over a warm ocean under the influence of a subtropical high a weak westerly baroclinic disturbance an approaching and departing typhoon danas to the east and the kuroshio current results show that the model reproduces the genesis final intensity looping track and the general convective activity of nari during the 4 day period it also captures two deep subvortices at the eye eyewall interface that are similar to those previously observed a few spiral rainbands and a midget storm size associated with nari s relatively dry and stable environment we find that 1 continuous convective overturning within the mcv stretches the low level vorticity and moistens a deep mesoscale column that are both favorable for genesis 2 nari s genesis does not occur until after the passage of the baroclinic disturbance 3 convective asymmetry induces a smaller sized vortex circulation from the preexisting mcv 4 the vortex vortex interaction with danas leads to nari s looping track and temporal weakening and 5 midlevel convergence associated with the subtropical high and danas accounts for the generation of a nearly upright eyewall

tropical cyclogenesis due to itcz breakdown idealized numerical experiments and a case study of the event in july 1988 abstractthe mechanism of tropical cyclogenesis due to the breakdown of the intertropical convergence zone itcz breakdown and the structure of associated vortices are studied by numerical experiments using a nonhydrostatic mesoscale model first an idealized numerical experiment in which a simple initial state without external disturbances is assumed is performed without cumulus parameterization a zonally uniform forcing of high sea surface temperature sst is imposed to generate an itcz like structure this itcz starts to undulate and eventually breaks down to form several tropical cyclones tcs these tcs merge and end up with a single tc the energy budget analysis shows that barotropic instability of the low level flow associated with the itcz is responsible for the genesis of vortices and tc scale buoyancy production soon takes over to contribute to the intensification of tcs conversion from the cumulus scale kinetic energy into the tc scale kinetic energy is found to be insignificant duri

genesis of tropical storm eugene 2005 from merging vortices associated with itcz breakdowns part iii sensitivity to various genesis parameters abstract in this study a series of sensitivity simulations is performed to examine the processes leading to the genesis of tropical storm eugene 2005 from merging vortices associated with the breakdowns of the intertropical convergence zone itcz over the eastern pacific this is achieved by removing or modifying one of the two vortices in the model initial conditions or one physical process during the model integration using the results presented in parts i and ii as a control run results reveal that while the itcz breakdowns and subsequent poleward rollup through a continuous potential vorticity supply provide favorable conditions for the genesis of eugene the vortex merger is the most effective process in transforming weak tropical disturbances into a tropical storm the sensitivity experiments confirm the authors previous conclusions that eugene would not reach its observed tropical storm intensity in the absence of the merger and would become much shorter lived without the potential vorticit