magnetic susceptibility of the rock matrix related to magnetic fabric studies non ferromagnetic minerals constitute what is called the rock matrix whose susceptibility k1 is directly accessible using only high magnetic fields measurements on minerals and a wide range of rock types show that k1 is mainly due to paramagnetism and hardly exceeds 10 3 si with an anisotropy degree p less than 1 35 different methods to estimate the role of the matrix component in low field susceptibility k and its anisotropy include petrological and chemical analysis evolution of p vs k low temperature studies and comparison of k with remanent magnetizations

the maladeta granite polydiapir spanish pyrenees a detailed magnetostructural study abstract the maladeta granitic complex spanish central pyrenees has been subjected to a detailed magnetostructural study through the systematic measurement of magnetic susceptibility and anisotropy of magnetic susceptibility at 253 regularly spaced sampling sites due to the dominant paramagnetic property of the granites a first order correlation can be derived between the susceptibility magnitude and the bulk rock iron content hence the petrographic nature of the rock the maladeta complex is shown to be composed of four principal juxtaposed plutons each one being normally zoned i e becoming more basic towards the periphery the largest pluton namely the colomers unit is itself made of a number of sub plutons due to distinct but more or less coeval batches of magmas the various magnetic data complemented by field and microstructural observations allow us to propose that the maladeta polydiapir probably exploited ne and se trending openings of the brittle crust for its emplacement that accompanied or just preceded a sw verging compressive event a later n s compression marked by inverse dextral and e w trending shears is preferably attributed to late variscan rather than to alpine tectonics

strain partitioning in a pluton during emplacement in transpressional regime the example of the neouvielle granite pyrenees this microstructural and anisotropy of magnetic susceptibility study of the internal structures of the hercynian neouvielle granite pluton 100 km2 provides new data indicating that the pluton was emplaced during the main hercynian tectonic event recognized in the pyrenees it also provides new data about the later alpine deformation localized along narrow mylonitic bands these bands acted as reverse faults and have not rotated the hercynian structures that define the main part of the pluton the pluton is composed of two structural domains the northern half of the pluton displays a beak shape in map view with subhorizontal e w trending lineations of magmatic origin the southern half is semi circular and displays rather steeply northward plunging lineations corresponding to magmatic and high temperature ht solid state microstructures these features are associated with magma deformation during emplacement magma deformation corresponds in the northern half of the pluton to an e w strike slip deformation recognized in the enveloping pelitic metasediments of carboniferous age and in the southern half of the pluton to southward overthrusting recognized in the enveloping quartzites of devonian age juxtaposition in a single granite body of transcurrent and compressive domains is viewed as a strain partitioning in the magma this strain partitioning is linked to both the transpressive character of the main regional deformation event and the rheological contrast between the pelitic country rocks and quartzose country rocks

magnetic fabric of the barrington passage pluton meguma terrane nova scotia a two stage fabric history of syntectonic emplacement abstract structural analysis and the anisotropy of magnetic susceptibility ams are used to document the internal magmatic to high temperature subsolidus fabrics of the tonalitic late devonian barrington passage pluton the ams fabric orientations compare favorably with mesoscopic scale fabrics in general the k1 k2 principal plane of the ams is close to the observed mineral foliation defined by biotite and plagioclase and the k1 axis is aligned parallel to a mineral lineation defined by the same minerals and to a locally developed weak extension lineation defined by quartz measurement of the anisotropy of anhysteretic remanence aar and image analysis of biotite preferred orientations confirm that the orientation of the ams is principally controlled by biotite locally anomalous ams orientations are attributed to the influence of fine grained magnetite crystals the presence of which is revealed by measurements of hysteresis and coercivity properties a two stage fabric history is revealed first horizontal fabrics were formed foliation compositional banding during emplacement of a laccolith like pluton the second stage involved synmagmatic folding of the horizontal foliation and banding in response to regional contraction associated with the acadian orogeny with development of a lineation that records stretching parallel to the fold axis the results demonstrate that the barrington passage pluton was emplaced during the main phase of the acadian orogeny a model is proposed that depicts the barrington passage pluton as the folded base of a larger syntectonic pluton that is now largely eroded off

magmatic fabric acquisition mechanisms in a syenite results of a combined anisotropy of magnetic susceptibility and image analysis study the structural significance of the anisotropy of magnetic susceptibility ams and acquisition mechanisms of silicate and ferrimagnetic mineral fabrics are investigated in the archean lebel syenite intrusion ontario canada bulk mineral subfabrics are determined by intercept counting of mineral phases in classified digital images of thin sections cut parallel to the principal planes of the magnetic fabric ellipsoids of the samples intensities shapes and principal direction orientations of the resulting intercept ellipsoids are generally similar to the corresponding ams ellipsoids differences are due mainly to bimodal distribution of mineral fabrics observed on foliation planes of some samples showing pre full crystallization textures and structural overprinting in samples deformed after crystallization subfabrics of clinopyroxene and magnetite in samples showing pre full crystallization microstructure are investigated by measuring inertia tensors of individual grain shapes the resulting inertia tensor ellipsoids indicate that magnetic fabrics in these rocks are strongly correlated to the shape preferred orientation of magnetite which is similar to the overall petrofabric of the samples crystal size distributions of clinopyroxene and magnetite indicate that they formed during in situ crystallization and that magnetite probably appeared late in the crystallization and flow history of the magma analysis of preferred orientations of these grains suggests that the petrofabrics of the samples were acquired during flow with strongly interacting grains analogous to a logjam in a river the final characteristics of the ams and silicate petrofabric are the end points of a continuous crystallization and flow history in the magma rather than transient late features

the guitiriz granite variscan belt of northern spain extension controlled emplacement of magma during tectonic escape abstract the ollo de sapo domain of the northern part of the variscan belt of spain contains precambrian and ordovician metamorphic rocks intruded by the guitiriz granite the domain is bounded by two n s transcurrent shear zones detailed structural and anisotropy of magnetic susceptibility studies of the guitiriz pluton reveal a syntectonic emplacement relative to movement on the two n s trending bounding shear zones characterized by 1 development of n s trending structural and magnetic fabrics 2 concordant structures in granites and country rocks and 3 development of shear zones along the east and west granite margins gravity data show two roots trending 110 e extending down to 4 5 km from an otherwise thin

the main variscan deformation event in the pyrenees new data from the structural study of the bielsa granite abstract a structural and magnetic fabric study of the bielsa granite axial zone of the pyrenees provides new data indicating that this pluton was emplaced during the main variscan event recognized in the pyrenees we argue that the later post triassic deformation was localized along mylonitic bands reactivating earlier variscan shear bands the bielsa granite intrudes cambro ordovician metasediments at its northern border and the pluton is unconformably overlain by sediments triassic in age to the south and east the main structures in the igneous body are magmatic foliations and lineations defined by feldspar phenocrysts and biotite and dextral shear bands with dominant wnw ese trends the wnw ese striking magmatic foliations have variable dips and the magmatic lineation a subhorizontal wnw ese trend the zonation of low field magnetic susceptibility coarsely related to mineral content indicates a layer arrangement of rock types with more basic compositions at the northern border the magnetic ellipsoids are prolate along a wnw ese central band and oblate at the pluton borders where flattening is more important all these data allow us to interpret the bielsa intrusion as being caused by coeval nne shortening and dextral shear the presence of shear bands indicates that strain localization under dextral transpression continued during late variscan times

characterization of the magnetic fabric of rocks abstract an inextensive system of magnetic susceptibility anisotropy factors is suggested which is sufficient in the majority of practical applications for characterizing the magnetic fabric of rocks the system involves three newly devised factors the corrected anisotropy degree the shape factor and the difference shape factor the first of these characterizes the quantity of anisotropy somewhat better than the commonly used anisotropy degree the shape factor characterizes the quality of anisotropy i e the shape of the susceptibility ellipsoid in a convenient way its definition is based on a certain analogy between the anisotropy ellipsoid and the strain ellipsoid the difference shape factor can replace the shape factor when only the differences between the principal susceptibilities are given while the mean susceptibility is unknown

stretching lineations in transpressional shear zones an example from the sierra nevada batholith california abstract ductile shear zones and associated stretching lineations are generally considered to be the result of two dimensional simple shear deformations with stretching lineations interpreted to rotate into parallelism with the direction of tectonic transport with increasing deformation however stretching lineations perpendicular to the inferred tectonic transport direction are displayed by some shear zones field studies in the sierra nevada batholith have revealed a single shear zone the rosy finch gem lake shear zone that contains both steeply plunging stretching lineations in older metamorphosed sedimentary and granitic rocks and shallowly plunging stretching lineations in syntectonic granitoids dextral sense of shear indicators are found in all these units and deformation occurred simultaneously along the length of the shear zone theoretical strain modeling indicates that stretching lineations can be either horizontal or vertical within transpressional shear zones to investigate the kinematics of three dimensional deformation we examine the role of stretching lineations which form as a result of finite strain including the possibility of partitioning a component of the strike slip movement onto shear bands comparing the field data with the strain modeling we interpret the along strike variation in lineation behavior within the rosy finch gem lake shear zone to be a result of the differences in finite strain recorded by different units the older units showing steeply plunging lineation have recorded more finite strain across a narrower shear zone than the syntectonic granites which record shallowly plunging lineations we conclude that the orientation of the lineation within transpressional shear zones does not necessarily correlate with the transport direction but may reflect along strike variations in finite strain and or strain partitioning

deformation mechanisms in granitic rocks at shallow crustal levels abstract microstructural observations of naturally faulted granitic gneisses show that feldspar grains are weaker than quartz grains at temperatures below 325 c and at depths of less than 8 10 km feldspar grains sustained most of the deformation by grain scale faulting slip along cleavage controlled fractures and cataclasis fracture of feldspar grains within fault zones promoted their alteration to kaolinite quartz grains also deformed by fracturing and often healed to form quartz porphyroclasts and mosaics in a comminuted matrix of feldspar and kaolinite syntectonic alteration of the feldspar grains may have weakened the fault zones over time and resulted in foliated textures within the fault zones this study of naturally deformed rocks confirms published experimental results on the behavior of granitic rocks at low temperatures and pressures and taken together these data show that the theology of the upper 10 km of the crust is greatly influenced by cataclastic processes in feldspar

u pb age and lead isotopic characterization of au bearing skarn related to the andorra granite central pyrenees spain auriferous skarns are associated with post and late kinematic hercynian granites that intruded into cambro ordovician to devonian sediments of the central pyrenees we determined the age of the andorra granite and the associated skarn at 305 3 ma by u pb dating titanite from the endo skarn the sulfur isotopic composition from sulfides in the skarn cardellach et al 1992 shows a significant variation with isotopically light sulfur 34s 3 in the barren skarns and heavy sulfur 34s 11 in the gold bearing skarns outwards it increasingly resembles sulfur from arsenopyrite disseminations in the cambro ordovician sediments the lead isotopic composition from sulfides of the skarns is very homogeneous 206pb 204pb 18 410 207pb 204pb 15 699 208pb 204pb 38 574 in contrast to the one in gold bearing arsenopyrite veins and in arsenopyrite disseminations in the sediments e g 206pb 204pb varies from 18 54 to 30 36 combined sulfur and lead isotope data indicate that the lead in the skarn is dominantly derived from the granite whereas the sulfur is derived at variable portions from both the granite and the sediments

variscan dextral transpression in the french pyrenees new data from the pic des trois seigneurs granodiorite and its country rocks abstract new structural data from both the trois seigneurs granodiorite and its country rock lead to new conclusions about the variscan tectonic history of this part of the pyrenees sedimentary rocks of the massif that increase in metamorphic grade from north to south are imprinted by a single major deformation responsible for both the tight upright e w trending folds with vertical to steeply n dipping foliations and the gently w plunging stretching lineations syntectonic emplacement of the pic des trois seigneurs granodiorite is demonstrated by the parallelism between structures of the pluton as determined by magnetic fabric measurements and the foliations and lineations imprinted in the country rocks large deformation of the granodiorite magma during emplacement is indicated by strong anisotropy and ubiquitous magmatic microstructures the high thermal gradients of regional metamorphism which is also syntectonic are attributed to a large thermal aureole provided by deep seated magma reservoirs shear sense criteria in xz thin sections of the metasedimentary country rocks indicate a dextral sense of the non coaxial component of strain throughout the massif and regardless of metamorphic grade the overall structure of the massif is concluded to have derived from a major shearing event that is equated with the d 2 main phase observed in the entire variscan pyrenees as the e w oriented stretch and dextral shear cannot be separated from compressive structures generally considered to be characteristic of d 2 this phase is concluded as representing regional transpression

magnetic mineralogy of some granites from the french massif central origin of their low field susceptibility abstract with a view to a better understanding of the origin of the low field susceptibility in the variscan granitoids of the french massif central for which extensive structural mapping using the anisotropy of magnetic susceptibility ams technique is currently applied a detailed study of magnetic carriers has been undertaken origin of the susceptibility has been studied using high field and low temperature measurements in a cryogenic magnetometer together with standard rock magnetic techniques additional determinations of the opaque phases have been performed with the metallographic microscope x ray microdiffraction and electron microprobe techniques in almost all the granite types the magnetic susceptibility is essentially carried by the paramagnetic biotite crystals minor amounts of ubiquitous oxides ilmenite rutile titano haematite do not contribute significantly to the susceptibility this is also the case for rare occurrences of magnetite in some granitoids mainly the cordierite bearing anatexites sulphides are found to give a large contribution magnetic mineralogy identifies a mixture of ferromagnetic pyrrhotite and antiferromagnetic fe9s10 hexagonal pyrrhotite hpo the latter species is identified as forming the larger unaltered pyrrhotite grains the ferromagnetic pyrrhotite is identified to be mainly smythite fe9s11 a species formed by supergenic alteration of monoclinic pyrrhotite located along the basal cleavage planes the microfractures and the grain boundaries of the hpo this study which constitutes the first report of the magnetic properties of smythite in rocks indicates that magnetic carriers derived from low temperature alteration have to be taken into account for purposes of structural studies using ams

magnetic susceptibility of the mont louis andorra ilmenite type granite pyrenees a new tool for the petrographic characterization and regional mapping of zoned granite plutons we have observed remarkably consistent patterns of concentric zonation in the values of low field magnetic susceptibility measurements over the variscan age mont louis andorra granite pluton of the eastern pyrenees of andorra spain and france this zonation is a function of the rock petrology since a close correlation is shown between the petrographic nature as defined by chemical analysis and the magnetic susceptibility magnitude of the rocks it reflects the dominantly paramagnetic nature of the granite carried by fe bearing silicates and this is demonstrated by the fact that low field susceptibilities of representative specimens are almost equal to 1 their high field susceptibilities and 2 their calculated susceptibilities using fe contents assuming a null ferromagnetic contribution we conclude that this technique accurately reflects the modal abundances of ferromagnesian phases in rocks of the ilmenite series and that it represents a powerful and efficient tool for the reconnaissance surveying of petrological variations in granitoid plutons

thrust tectonics in the south central pyrenees abstract surface structural data and published stratigraphies are combined to construct two balanced and restored sections through the nogueras zone of the south central pyrenees the allochthonous nogueras zone units are interpreted as the foreland dipping margin of a major antiformal stack in the palaeozoic rocks of the pyrenean axial zone their structural evolution is summarized in a hangingwall sequence diagram this reinterpretation of the nogueras zone is incorporated into a new n s balanced and restored section from the centre of the pyrenean axial zone to the ebro basin a classical rocky mountains piggy back thrust model is employed and the resulting section is a significant departure from those previously published it is argued that gravity gliding has never been an important mechanism in the alpine pyrenees section restoration casts doubt on the correlation of the surface expression of the north pyrenean fault and the seismically detected moho step beneath it

the variscan geology of the pyrenees abstract the main outlines of the geology of the variscan part of the pyrenees are discussed rocks involved in this cycle are high grade basement gneisses palaeozoic sediments and their metamorphic equivalents late intrusive granodiorites and early pre variscan granites the main features of the stratigraphy of the palaeozoic are given structures fall into two domains a low grade suprastructure essentially with steep folds and cleavages and a high grade infrastructure with dominantly low dipping foliations an important phase of early pre cleavage folding occurs in low grade rocks mainly along the southern border of the axial zone in high grade rocks most structures and the metamorphism postdate the main cleavage phase in low grade rocks the influence of the alpine orogeny on the variscan structures consists mainly of faults steep reverse faults in the northern and south directed thrusts in the southern part of the pyrenees metamorphism took place under high geothermal gradients and low pressures as indicated by the abundant occurrence of andalusite and cordierite

paleomagnetism of the north patagonian batholith southern chile an exercise in shape analysis abstract over 100 sites in granitic country rock mafic inclusions within granitic rock and mafic dikes were sampled in the northernmost 550 km of the patagonian batholith after magnetic cleaning some sites were rejected as magnetically unstable and others were combined because they were contiguous and carried similar directions hence probably representing duplicate samplings of the same direction of the geomagnetic field a total of 42 well determined directions 29 from granitic country rock and inclusions and 13 from dikes survived to be included in the interpretation most of these had a normal magnetic polarity probably indicating that a disproportionate fraction of the north patagonan batholith formed during the mid cretaceous long normal interval tectonic interpretation of paleomagnetic directions from intrusive rocks often is difficult because paleohorizontal indicators in such rocks are usually lacking rather than struggle against this limitation we yielded to it and elected to concentrate on the shapes of our various data sets the method used is simple and straightforward involving bingham statistics and small circle fitting from this analysis it appears that the main structural feature within the north patagonian batholith npb the liquine ofqui fault zone is a site of crustal detachment a sliver of south america west of the fault is detached from the rest of the continent and has moved relatively northward because the main strands of the liquine ofqui fault are curved and concave to the west northward movement was accompanied by counterclockwise rotation east of the fault the npb appears to have been the locus of distributed shear mainly dextral the principal period of deformation of the batholith appears to have been mid or late cenozoic and may have been initiated by the arrival of the south america nazca farallon phoenix aluk triple junction

magnetic anisotropy of some phyllosilicates magnetic susceptibility anisotropy of susceptibility and hysteresis of single microcrystals of chlorite biotite phlogopite muscovite zinnwaldite and fuchsite were measured in low and high magnetic fields with an alternating gradient force magnetometer micromag their properties are sufficient to account for the low field susceptibility ams of most micaceous rocks nearly all samples show some ferromagnetic contribution at low fields due to inclusions of pseudosingle domain and multidomain magnetite the paramagnetic contribution isolated at high fields usually exceeds the ferromagnetic contribution the paramagnetic susceptibility is intrinsic to the silicate lattice and agrees with values predicted from chemical composition within the limits of error the minimum susceptibility is nearly parallel to c another axis is parallel to b and the third susceptibility usually the maximum is close to a the paramagnetic susceptibility has a disk shaped magnitude ellipsoid with strong anisotropy p 2 the ferromagnetic contributions at low fields have more variably shaped ellipsoids with greater eccentricity p 5 the silicate lattice does not constrain their orientation our technique cannot determine the principal axes of the ferromagnetic component however its principal values usually correspond with the paramagnetic principal susceptibilities in order of magnitude thus the combined paramagnetic ferromagnetic anisotropy recognised in routine studies of ams should faithfully represent the petrofabric of most micaceous rocks nevertheless nearly 10 of our samples have incompatible anisotropy ellipsoids for the silicate host and magnetite inclusions these yield a net inverse ams that does not correctly represent the orientation of the silicate lattice therefore some caution is necessary in petrofabric ams studies of micaceous rocks

a dynamic model of the structural evolution of the hercynian pyrenees abstract the structural history of the hercynian pyrenees is considered with respect to the relationships between the metamorphism and the successive deformations the characteristics and mode of emplacement of the gneissic and anatectic cores of the metamorphic domes the migmatization and the intrusions of plutonic and basic and ultrabasic rocks the metamorphism can be shown to have progressed upwards with time attaining the presently exposed levels just before during and a short time after the major penetrative regional deformation the intrusion of major plutonic anatectic and gneissic massifs which has determined the metamorphic domes in country rocks was roughly synchronous with the progression of the metamorphism but seems to have continued later in the uppermost levels the basic and ultrabasic rocks uplifted by the intrusion of the anatectic cores of the metamorphic domes have been deformed and foliated by the major regional penetrative deformation thus showing that their intrusion predated this deformation in the lowermost levels these results together with the presently available sedimentological data lead us to propose a dynamic model of the tectonic evolution of the hercynian pyrenees the first step was a crustal extension and thinning attaining its maximum during frasnian time marked in the upper levels by a horst and graben controlled sedimentation and in the lower crust by intrusions of basic magmas and the onset of the very low pressure metamorphism and anatexis characteristic of the hercynian pyrenees the second step was a crustal shortening marked by large scale crustal thrusting followed by widespread regional penetrative deformation the flysch troughs formed in front of the progressing and emerging thrusts in lower levels the thrusts are believed to have controlled the progressive ascent of the plutonic and anatectic magmas which continued their uplift and emplacement during major penetrative regional deformation in the actual mesozone and probably after it in the uppermost levels

paleoseismology and slip rate of the western tianjingshan fault of ne tibet china abstract we present results from a detailed investigation of the horizontal displacement distribution timing of paleoearthquakes and left lateral slip rate on the western tianjingshan fault measurements of 240 offset streams and ridges confirm that the fault is left lateral and record evidence of repeated 3 4 m coseismic offsets along the 60 km long fault this suggests that 6 earthquakes may have occurred along the entire western tianjingshan fault with repeated occurrence of earthquakes of mw 7 2 7 5 structural and stratigraphic relationships exposed in our five trenches in combination with previously reported studies further indicate that the fault has ruptured in as many as six paleoearthquakes since the late quaternary paleoseismic data show that the average recurrence interval for holocene earthquakes is approximately 5 000 yr the most recent earthquake along the western tianjingshan fault occurred 1 2 0 1 kyr bp indicating that this fault segment did not rupture in the m 7 5 historical earthquake of 1709 that ruptured the central tianjingshan fault we estimate that the holocene slip rate of the western tianjingshan fault is 1 1 1 2 mm yr based on measurements of the age and offset of stream channels compared with the relatively fast slip rate of the haiyuan fault 4 6 mm yr we suggest that the tianjingshan fault acts as an essential active fault accommodating the sinistral displacement and crustal shortening deformation in ne tibet

syntectonic emplacement of the maladeta granite pyrenees deduced from relationships between hercynian deformation and contact metamorphism the relationships between hercynian deformation and contact metamorphism in the aureole of the aneto unit a constituent pluton of the maladeta granite complex spanish pyrenees provide new data relevant to the controversy between the syn and post tectonic models of emplacement for the pyrenean granites the deformation in the aneto aureole is related to two superimposed hercynian episodes the first was a top to the sw thrusting which induced sw verging recumbent folds the second which was essentially compressive in the aneto area is represented by e w trending subvertical cleavage and folds with subhorizontal axes this second episode can be assigned to the d2 main hercynian tectonic event of the pyrenees the contact metamorphic assemblages grew during the d2 event and were deformed by it close to the contact the conclusion that the pluton was emplaced during d2 is strengthened by the structural and kinematic similarities between the magmatic deformation in the southern rim of the pluton and the d2 deformation in the country rocks this syntectonic timing is supported by new geochronological data that conflict with an existing rb sr post tectonic permian whole rock age for the maladeta granite more generally in accordance with some very recent structural and u pb zircon studies our results contradict the geodynamical models of the pyrenees which relate the granite intrusions to a late extensional event

development of a tool for managing groundwater resources in semi arid hard rock regions application to a rural watershed in south india until recently aquifers located in hard rock formations granite gneiss schist were considered as a highly heterogeneous media and no adequate methodology for groundwater management was available recent research studies have shown that when hard rocks are exposed to regional and deep weathering processes and when the geology is relatively homogenous a typical hard rock aquifer is made of two main superimposed hydrogeological layers each characterized by quite homogeneous specific hydrodynamic properties namely the saprolite and the fissured layers therefore for these cases hard rock aquifers can be considered as a multi layered system based on these works an operational decision support tool dst gw designed for the management of groundwater resources in hard rock area under variable agro climatic conditions has been developed the tool focuses on the impact of changing cropping pattern artificial recharge and rainfall conditions on groundwater levels at the scale of small watersheds 10 to about 100 km2 in case well developed weathering profile dst gw is based on the groundwater balance and the water table fluctuation method which are well adapted methods in hard rock and semi arid contexts based on field data from an overexploited south indian watershed 58 km2 the model allows calibrating at watershed scale the variation in specific yield of the aquifer with depth as well as the rainfall aquifer recharge relationship seasonal basin scale piezometric levels are computed with an average deviation of 0 56 m compared to measurements from 2001 to 2005 the model shows that if no measure is taken the water table depletion will induce the drying up of most of the exploited borewells by the year 2012 scenarios of mitigation measures elaborated with the tool show that change in cropping patterns could rapidly reverse the tendency and lead to a sustainable management of the resource this work presents the developed tool and particularly the hydraulic model involved in and its application to a case study however the purpose tool is applicable at watershed scale but not design for the groundwater management of a very small area or for a single borewell copyright 2010 john wiley sons ltd