Geo logi cal con di tions of ground wa ter oc cur rence in the Pi en iny Klip pen Belt (West Car pa thi ans, Po land) 2

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1 STU DIA GEO LOGICA PO LO NICA Vol. 132, Kraków 2009, pp Ge ol ogy of the Pi en iny Klip pen Belt and the Ta tra Mts, Carpathians Ed ited by K. Birkenmajer Part XX W³odzim ierz HUM NICKI 1 Geo logi cal con di tions of ground wa ter oc cur rence in the Pi en iny Klip pen Belt (West Car pa thi ans, Po land) 2 (Figs 1 6; Tabs 1 7) Abstract. The pa per pres ents se lected re sults of hydro geo logi cal re search car ried out in the Pi en iny Na tional Park and ad ja cent ar eas dur ing the pe riod of The ob jec tives of the stud ies were to ex plore the geo logi cal en vi ron ment and con di tions of groundwater occurrence, its circulation and drain age sys tem, as well as the physico- chemical prop er ties of ground wa ters. An im por tant part of the re search were rock fis sur ing meas ure ments in natu ral out crops which made it pos si ble to de ter mine the fis sures spa tial ori en ta tion, the fis sur ing pa rame ters, and the fis sure per me abil ity co ef fi cient. In ves ti ga tions of rock ma trix hydro geo logi cal pa rameters in selected lithostratigraphic complexes of the Pi en iny Klip pen Belt were also car ried out. Ground wa ter oc cur rence con di tions in al lu vial and weath er ing cover de pos its are char ac ter ized as welll. Key words: Pi en iny Klip pen Belt, hydro geo logi cal studies, rock matrix parameters, permeability co ef fi cients. INTRODUCTION The Pi en iny Klip pen Belt has a spe cial po si tion not only in the ge ol ogy but also in the hy dro ge ol ogy of the Pol ish Car pa thi ans. De pos its com pos ing the Pi en iny Klip pen Belt are so strongly folded, im bri cated and lo cally shat tered into lenses and metre- sized blocks that Birk en ma jer (1958) and Œwidzi ñski (1962) called them tec tonic megabrec cia. A mo saic geo logi cal struc ture, mani fested by a wide range of rock types vary ing over small ar eas, ob vi ously con trols the vari abil ity and com - plex ity of hydro geo logi cal con di tions within the Pi en iny Klip pen Belt. 1 Faculty of Geology, University of Warsaw, al. wirki i Wigury 93, Warszawa; w.humnicki@uw.edu.pl 2 Manu script ac cepted for pub li ca tion June 15, 2009.

2 40 W. HUMNICKI In hydrogeological terms, the Pieniny Klippen Belt has a two-fold char ac ter. Down to a depth of tens of metres, fis sure, fis sure-karst and pore wa ters of the Tatra Mts and Podhale, in clud ing the Pieniny Klippen Belt, be long to a joint near-sur face aqui fer strongly re spond ing to cli ma tic fac tors and vul ner a ble to di rect in fil tra tion of sur face con tam i nants. In this case, the whole up per part of the Dunajec drain age ba sin is a co her ent hydrogeological sys tem and its bound aries are de lim ited by sur - face watersheds (Ma³ecka, 1981). The deep ground wa ter cir cu la tion sys tem ex plored by a num ber of deep ex plor - atory wells shows dif fer ent fea tures. Me te oric wa ters, in fil trat ing across the Tatra Mts mas sif per co late, con sis tently with the dip of aqui fers down to be neath the Podhale Flysch, into a typ i cal ar te sian ba sin. Mov ing north wards, they meet a tight bar rier of the Pieniny Klippen Belt rocks which force the change of flow di rec tion to the latitudinal one (Ma³ecka, 1992). Neg a tive hydrogeological re sults of the Maruszyna IG-1 bore hole sup ported ear lier views that the north ern flank of the Podhale Trough is a bar rier to deep groundwaters (Macioszczyk, 1964; Ma³ecka, 1981). Ac cord ing to Birkenmajer (1986), this bore hole pierced a num ber of strongly folded and brecciated rock units and their Up per Cre ta ceous man tle. The strata ver ti cal po si tion sug gests that a sim i lar struc tural style may be ob served down to a depth of at least 5 km. The pa per pres ents se lected re sults of hydrogeological re search car ried out on the near-sur face aqui fer in the Pieniny Na tional Park and ad ja cent ar eas (Fig. 1). The in ves ti ga tions were con ducted in the years The main ob jec tives were to ex plore the geo log i cal set ting and con di tions of ground wa ter oc cur rence, the wa ter cir cu la tion and drain age sys tems as well as physico-chem i cal prop er ties and qual ity of ground and sur face wa ters (Ma³ecka & Humnicki, 2001, 2002; Humnicki, 2003, 2005, 2007). The Pieniny Klippen Belt pres ents a valu able test area al low ing the rec og ni tion of nat u ral hydrogeological con di tions within an area undisturbed by direct human economic activity. It is ob vi ous that only se lected na ture-friendly re search meth ods could be used to ex plore hydrogeological con di tions in this valu able, unique and pro tected area. RE VIEW OF PRE VI OUS HYDROGEOLOGICAL STUD IES IN THE PIENINY KLIPPEN BELT With the abun dance of pa pers on the his tory of the evo lu tion of the Pieniny Klippen Belt geo log i cal-struc tural unit, hydrogeological re ports fo cus ing on the Pieniny Mts. them selves and their im me di ate neigh bour hood are scarce. Both early no tices from the mid-19-th cen tury on hydrogeological prob lems in this re gion and later re ports (e.g. Szajnocha, 1891) mostly dis cussed a much greater area of the In - ner Carpathians, in clud ing the Tatra Mts. and Podhale which were the ar eas of most in ter est. Re search ers fo cused mostly on the oc cur rence of wa ter springs, their or i - gin and es pe cially on hydrochemical char ac ter is tics of wa ter. In the Pieniny re gion, the great est at ten tion was paid to min eral wa ter springs at Kroœcienko upon

3 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 41 Fig. 1. A. Position of the Pieniny Klippen Belt (in black) in the West Carpathians (after Birkenmajer & Gedl, 2007); B. Geological sketch of the Pieniny Klippen Belt (after Birkenmajer & Gedl, 2007, modified), with position of the studied section in the Pieniny Klippen Belt. a fissure measurements; b d determinations of hydrogeological parameters of the rock matrix: b Klenina (No 2, 3 after Table 4); c near Falsztyn (No 13 and after Table 4); d G³êboki, Limbargowy, Straszny, Macelowy and Szopczañski stream catchments (No 1, 4 12 and after Table 4). 1 Miocene faults; 2 Miocene andesite intrusions; 3 Miocene fresh-water aquifers; 4 Podhale Palaeogene (autochthonous); 5 Magura Palaeogene (Magura Nappe and autochthonous Palaeogene in the Pieniny Klippen Belt); 6 Jarmura Formation (Maastrichtian): Grajcarek Unit and Pieniny Klippen Belt; 7 Jurassic Campanian of the Grajcarek Unit; 8 13 Klippen successions (8 Czorsztyn; 9 Czertezik; 10 Niedzica; 11 Branisko; 12 Pieniny; 13 Haligove); 14 studied area

4 42 W. HUMNICKI Dunajec, Szczawnica and Èervený Kláštor (Korczyñski, 1909; Marchlewski, 1914a, b; Go³¹b, 1948, 1952; Birkenmajer, 1956, 1963; Hynie, 1963; Barczyk, 1986; Poprawski et al., 1995; Rajchel et al., 2003; Ciê kowski & Rajchel, 2005). Stud ies of iso to pic com po si tion of wa ter and its con stit u ents highly con trib uted to the rec og ni tion of the or i gin of min eral wa ters in the Pieniny Mts. fore land. Dis - cus sions on the or i gin of the Kroœcienko and Szczawnica min eral wa ters are still tak ing place, and the dif fi cult prob lems of evo lu tion and spe cific com po si tion of the min eral wa ters have not been decisevely ex plained so far (Dowgia³³o, 1980; Zuber & Grabczak, 1985; Oszczypko & Zuber, 2002). Geo log i cal and hydrogeological stud ies of the area in cluded also the prob lems of wa ter springs lo cated at the con tact zone of the Pieniny Klippen Belt with Podhale Flysch Ba sin (Watycha, 1959; Macioszczyk 1959, 1964) and the Magura unit (Bober & Oszczypko, 1963a, b; Oszczypko, 1963; Kostrakiewicz, 2002). In all re gional hydrogeological re ports and maps con cern ing the Carpathians (Kolago, 1970; Chowaniec et al., , 1981; Ma³ecka & Murzynowski, 1978; Ma³ecka, 1981, 1982; Malinowski, ed., 1991), the Pieniny Mts were treated as an un di vided whole. In the Hydrogeological map of Podhale and ad ja cent areas, scale 1:100,000 (Ma³ecka, 1982), the Pieniny Klippen Belt was char ac ter - ized as an area of highly vari able li thol ogy and com plex tec tonic struc ture where nu mer ous folds and slices, cut by a dense fault net work, pro duce com pli cated sys - tems of fis sure wa ter cir cu la tion. That au thor paid at ten tion to the prev a lence of run-off over in fil tra tion, to small stor age ca pac ity of the rock vol ume man i fested by low spe cific dis charge of wells and springs, as well as to hy drau lic con nec tion of pore wa ters from the Dunajec al lu vial deposits and fissure waters in the bedrock. A de tailed hy dro graphic anal y sis of the Pieniny Na tional Park area was pro - vided by Kostrakiewicz (1965). In his study much at ten tion was de voted to the Pieniny springs, their types, dis charge rates and wa ter min er al iza tion. His in ter est in crenology of the Pieniny area re sulted in pub li ca tion of fur ther pa pers (Kostrakiewicz, 1982, 1991a, b, 1992, 1993, 1995, 1996). A new re search field was de vel oped in the Pieniny re gion dur ing the con struc - tion of the Czorsztyn dam on the Dunajec River. A num ber of hydrogeological re - ports as so ci ated with this pro ject were aimed at the rec og ni tion of hydrogeological and geo log i cal-en gi neer ing con di tions and at the as sess ment of the sur face wa ter res er voir in flu ence on ground wa ter. Worth not ing are the com pre hen sive re ports by Niedzielski (1965), ukaszek and Niedzielski (1973, 1976), Dziewañski (ed., 1998) with ref er ences given therein, and by Ma³ecka (1996) and Ma³ecka et al. (1996). Map ping works on the Szczawnica-Kroœcienko sheet of the Hydrogeological Map of Po land, on the scale 1:50,000 (Chowaniec & Witek, 1997a, b) re sulted in ex plo ra tion of the Qua ter nary aqui fer in the east ern area. It is com posed of gravel and sand de pos its fill ing the Dunajec River val ley along the sec tion from the river dam at Sromowce Wy ne to Sromowce Ni ne (units No 2a Q II and No 3a Q II). An other Qua ter nary aqui fer was char ac ter ized in the area cov er ing the Dunajec River val ley from Szczawnica-Piaski in the south to Kroœcienko- ¹kcica in the

5 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 43 north (unit No 1 aq/tr II). Ac cord ing to the re quire ments of the map con struc tion pro ce dures, ground wa ter qual ity and vul ner a bil ity cat e go ries were de ter mined for these units. No hydrogeological char ac ter is tics were given for ar eas com posed mostly of the Podhale Flysch shales and those be long ing to the Pieniny Klippen Belt due to great di ver sity of the geo log i cal struc ture and com monly low wa - ter-bear ing ca pac ity (Chowaniec & Witek, 1997b). These ar eas were con sid ered water less be cause they have not met even the very low cri te ria adopted for the Carpathians: thick ness of the aqui fer at least 2 3 m, transmissivity of 25 m 2 /24h and well s po ten tial dis charge of 2 5 m 3 /h (Paczyñski, ed., 1999). In the early 1970s, D. Ma³ecka started de vel op ing a ground wa ter mon i tor ing net work cov er ing se lected wells and ground wa ter springs in the Tatry and Podhale re gions, in clud ing the Pieniny Klippen Belt. Data ob tained from the mon i tor ing were ana lysed against the re gional hydrogeological back ground of the up per part of the Dunajec drain age ba sin and pre sented in a num ber of pub li ca tions (Ma³ecka, 1985, 1996; Ma³ecka & Humnicki, 1989; Ma³ecka & Lipniacka, 1990; Kazimierski et al., 1999). Worth not ing is also a re port by urawska (2002) who dis cussed the prob lem of wa ter-bear ing ca pac ity of the Pieniny Klippen Belt, based on ground wa ter mon i - tor ing re sults of sev eral springs lo cated in its west ern part. These data were com - pared with car to graphic ma te rial, show ing that rocks form ing the Pieniny Klippen Belt can not be con sid ered water less. In terms of hydrogeological pa ram e ters, they dis play a char ac ter is tics sim i lar to the Podhale Flysch deposits. In the Slovakian part of the Pieniny Mts, geo log i cal and hydrogeological in ves - ti ga tions were car ried out to a lesser ex tent and at smaller map scales. The Pieniny re gion was treated in Slovakia to gether with the ad ja cent ar eas of the Èergovska, ¼ubovnianska and Ondavska vrchovina (Nemèok, 1981 ed., 1990; Jetel, 2000). A hydrogeological map on the scale 1:50,000 by Jetel (2000), cov er ing, like a geo log i cal map of this re gion, a much larger area, pro vides a gen eral char ac ter is tics of the Pieniny Mts ground wa ter, in di cates high est dis charge of springs and pres ents approximate intervals of transmissivity coefficient values with close reference to the lith o logic units de picted in the map by Nemèok (1981). Due to the lack of drill - ing ex plo ra tion in this area, in di rect geo log i cal meth ods were ap plied (Jetel & Kullmann, 1989; Jetel, 1989) and wide-rang ing anal o gies to other Carpathian regions were made. The Pieniny Mts are very poorly ex plored by hydrogeological drillings. The only pro duc tive drilled wa ter well within the the Pieniny Klippen Belt is lo cated at Szczawnica near the mouth of the Dunajec Gorge. It sup plies wa ter to a tour ist in - for ma tion hall of the Pieniny Na tional Park. Its depth is 30.0 m and wa ter is ex - tracted from lime stones of the Pieniny Lime stone For ma tion. The max i mum pump - ing test dis charge was 2.4 m 3 /h at a drawdown of 15.5 m. Ad mis si ble vol ume of ex - tracted ground wa ter is es ti mated at 2.2 m 3 /h with a drawdown of 11.8 m (Tab. 1). The re main ing wells in the Pieniny Klippen Belt have ap peared ei ther to be neg - a tive ones with very low, if any, dis charge rates, or they are lo cated out side the area of the Pieniny Mts (at Szaflary).

6 Water wells extracting fissure water in the Polish part of the Pieniny Klippen Belt and adjacent areas (based on data from the Central Hydrogeological Database HYDRO) Table 1 No. Map sheet 1: Object number after Hydro database Locality User Geologic unit Pieniny Klippen Belt Year of drilling Well Depth [m] Elevation [m a.s.l.] Lithology Aquifer Top [m] Thickness [m] Ground water table depth [m b.g.l.] Permeability coefficient Bottom [m] drawdow n [m] Sromowce Wy ne Shales and Cr > Oœr. Turystyczny N3 sandstones > Szczawnica - Sromowce Ni ne Limestones and Cr > Kroœcienko Ujêcie PPN -2 shales > Szczawnica Limestones and Cr-J > Ujêcie PPN -1 shales > Szaflary Marly Cr > Wytwórnia Nart 1 limestones > Szaflary Marly Cr Wytwórnia Nart 2 limestones Nowy Targ Szaflary Shales and Cr-J > Wytwórnia Jogurtu limestones > Szaflary J 3 Limestones St. pryw. P. Uznañski Osada Tur.Czorsztyn Fine-grained Tr Kluszkowce K-1 sandstones Kluszkowce Sandstones and Tr > Przystañ Wodna W-1 shales > Czorsztyn Oœrodek Kolonijny Cr3 7.0; ; Szczawnica Kroœcienko Szczawnica Zdrój Zak³. Uzdrowiskowy 4 Szczawnica Zdrój Szczawnica PD-4 Szczawnica Zdrój Szczawnica PD-4 Kroœnica Szko³a Podst. KS1 Ha³uszowa Bacówka C2 Kroœcienko n/d Zak³. Goldfruct SKO1 Magura Unit Fine-grained sandstones and shales Cr3 Sandstones Cr Stratigraphy Mediumgrained sandstones Cr3 Sandstones Cr Cr Cr3 Fine-grained sandstones Sandstones and shales Calcareous sandstones 12.5; ; > > > >3.1 [m/s] [m/24h] > > > > Resources [m 3 /h] Well discharge (at ma imum test pumping discharge) [m 3 h*1m]

7 44 W. HUMNICKI There are some more wells ex tract ing ground wa ter from the Magura unit flysch. A well drilled at the Czorsztyn Chil dren Camp Cen tre (No 175, depth 49.7 m) ex - tracts ground wa ter from Cre ta ceous fine-grained sand stones and shales at a depth in ter val of m. The max i mum pump ing test dis charge was 5.8 m 3 /h. Ad - mis si ble vol ume of ex tracted ground wa ter is ap proved at 1.5 m 3 /h with a drawdown of 9.2 m. An in ter est ing shal low well was drilled in 1995 for the Kroœcienko Goldfrukt Com pany; it yielded up to 7.0 m 3 /h (the drawdown was barely 0.9 m) fresh wa ter from Paleogene of the Magura Nappe cal car e ous sand stones. That well, sit u ated within a fault zone of the Kroœnica River val ley, is an ex am ple that it is pos si ble to en coun ter a frac tured zone of slightly better hydrogeological prop er ties, ca pa ble of sup ply ing greater amounts of ground wa ter. The well pro duces a very pop u lar brand of min eral wa ter Kinga. In re cent years, a num ber of wells have been drilled in this area to ex tract high qual ity wa ter for drink ing pur poses ( Kinga Pieniñska, Trzy Korony, Szczawnicki Zdrój ). RESEARCH METHODS The most typ i cal fea tures of the ground wa ter en vi ron ment in the Pieniny Klippen Belt are both a con sid er able lithological di ver sity and a par tic u larly high de gree of tec tonic de for ma tion. The rocks are so tec toni cally dis turbed that their dif fer ent types of ten dis play wide-rang ing sim i lar i ties in their hydrogeological prop er ties, in de pend ently of what rock se ries they be long to. There fore, a sig nif i - cant gen er al iza tion was made while clas si fy ing the rocks from the hydrogeologicasl point of view. They have been di vided into four groups: car bon ate de pos its (about 10% of the Pieniny Mts ter ri tory), car bon ate-clay de pos its (26%), flysch de - pos its (36%) and Qua ter nary de pos its (28%) (Humnicki, 2007). Im por tant el e - ments for de ter mi na tion the pos si bil ity of both oc cur rence and cir cu la tion of ground wa ter in the first three rock groups were fis sure mea sure ments (car ried out in nat u ral exposures) and laboratory investigations of the rock matrix hydrogeological parameters. Fissure measurements Fis sure mea sure ments of the rock mass in nat u ral out crops en abled the de ter mi - na tion of fis sures spa tial ori en ta tion and of fis sur ing pa ram e ters, as well as fis sure per me abil ity co ef fi cients cal cu la tion for se lected lithostrati graphic com plexes of the Pieniny Klippen Belt. By ap ply ing stan dard meth ods of fis sure mea sure ments in rock masses (Liszkowski & Stochlak, eds., 1976), 1121 frac tures and fis sures were mea sured in 87 out crops on the south ern slopes of the Pieniny Mts, from the G³êboki Stream drain age ba sin in the west to the Szopczañski Stream drain age ba - sin in the east (Fig. 1). The fol low ing pa ram e ters of fis sures were mea sured: length, open ing (ap er ture), rough ness (on a macro scale) and surface density (spacing). Fis sure open ing was de ter mined bas ing on di rect mea sure ments and av er ag ing the value sep a rately for each fis sure. In case of sur face fis sure den sity and fis sure

8 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 45 rough ness n vs, the val ues were av er aged within the same mea sur ing site, most of ten hav ing an area of 1 m 2. The fol low ing for mu las were ap plied (Liszkowski & Stochlak, eds., 1976): where: sur face fis sure den sity [m/m 2 ]; l fis sure length [m]; F mea sured area [m 2 ]. = l i /F [1] n vs = ( 2 /4) n F = n F [2] where: n vs fis sure po ros ity [%]; n F co ef fi cient of sur face fis sur ing [%]; b mean fis sure open ing [m]. n F = ( (b i l i )/F) 100% [3] De ter mi na tion of rock ma trix hydrogeological pa ram e ters De ter mi na tions of hydrogeological pa ram e ters of the rock ma trix were done on four dif fer ent rock com plexes. The in ves ti ga tions in cluded de ter mi na tion of val ues of both open po ros ity co ef fi cient us ing he lium method, and of the hy drau lic per me - abil ity co ef fi cient. The mea sure ments were made at the Petrogeo lab o ra tory at Wo³omin. Open po ros ity was mea sured by means of the EPS HGP-200 porosimeter us ing the HELPOR soft ware. He lium was ap plied, as a small mol e cule gas ca pa - ble of pen e tra tion into pores and even micropores be low 1 micrometre in size. A hy - drau lic per me abil ity anal y sis was made us ing the EPS DGP 200 gas permeabilime ter and the GASPERM soft ware; a ni tro gen flow through a 1-inch di am e ter rock sam ple mounted in a spe cial han dle (a tightly fixed rub ber col lar) was ap plied. The col lar was sup ported by sur round ing outer pres sure to pre vent the gas to es cape out of the rock vol ume. Thin sections were prepared from all of the rock samples to identify rock types. Determination of permeability coefficient Determination of fissure permeability coefficient in a fractured massif is a more dif fi cult and com pli cated task than it is in po rous de pos its. There are a num ber of for mu lae de vel oped in the lit er a ture, which use the re sults of field fis sure mea sure - ments to cal cu late the per me abil ity co ef fi cient (Liszkowski & Stochlak, eds., 1976; Krajewski & Herbich, 1977;. Motyka & Wilk, 1984; Leœniak & Motyka, 1991; Motyka & Zuber, 1993). The mean fis sure open ing plays a sig nif i cant role in all these for mu lae be ing raised to the sec ond or third power. It ap pears that the way of averaging affects the obtained results and may change the permeability coefficient

9 46 W. HUMNICKI by or ders of mag ni tude. Motyka and Zuber (1993) rec om mend us ing the weighted geo met ric mean of fis sure lengths (b gw ) to the cal cu la tions. Such a method was used not only while de ter min ing per me abil ity co ef fi cients in Tri as sic lime stones from the south ern part of the Cra cow-czêstochowa Up land (Motyka & Zuber, 1993; Motyka, 1998), but also in the Tatra Mts. (Barczyk et al., 1995). The se lec tion of fis sure open ings av er ag ing is equally im por tant as the se lec tion of an ap pro pri ate cal cu la tion scheme. It was de cided to limit the num ber of for mu - lae to two, us ing two dif fer ent ways of av er ag ing fis sure open ings in or der to sim - plify fur ther con sid er ations. In ad di tion, the cal cu la tions were made us ing the two for mu las as sum ing the same con stant value of fis sure open ings b = 0.3 mm. This value has been adopted af ter Lenk (1986), who car ried out some ex per i ments on the be hav iour of fis sures in car bon ates and dis cov ered that be low a depth of 300 m the fis sure open ing be comes con stant and keeps the value of 0.3 mm. As the re sult of these cal cu la tions made for dif fer ent vari ants, six dif fer ent values of fissure permeability coefficient have been obtained. The fol low ing for mu lae were ap plied: The for mu lae of Kotiachow-Johns (Krajewski & Herbich, 1977) mod i fied by Motyka and Zuber (1993): k = ( b 2 n F )/(f 1 f 2 ) [4] The for mula of Liszkowski and Stochlak (eds.,1976): k = b 3 [5] where: k fissure permeability coefficient [m/s] b mean fis sure open ing [m] n F sur face fis sur ing [ ] cal cu lated ac cord ing to for mula [3] F area of the rock sur face [m 2 ] f 1 co ef fi cient in volv ing fis sure wall un even ness and tortuosity of fis sures (1.0<f 1 <1.5); f 1 = 1.5 means rough and tor tu ous fissures f 2 co ef fi cient in volv ing the tortuosity of fis sures and an uniformly distributed fissure system (1.0<f 2 <1.5) (f 2 = 1.5 means tor tu ous fis sures of uni formly dis trib - uted ori en ta tions) mean sur face den sity of fis sures [m/m 2 ] cal cu lated ac cord ing to for mula [1] The ways of fissure parameters averaging: a) b gw geo met ric mean of fis sure open ings weighted upon fis sure lengths (Motyka & Zuber, 1993) b gw = ( b i b gw l i ) 1/n /( l i /n) [6] where: b fis sure open ing [m]

10 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 47 l fis sure length [m] n num ber of mea sured fis sures [ ] b) b m war ranted av er age cu mu la tive fre quency, de ter mined by the Pilgunova method (Liszkowski, & Stochlak, eds., 1976); with the num ber of mea sure ments 75<n<120, the vari a tion in ter val lim its are as sumed to cor re spond to 40% (lower limit) and 60% (up per limit) of the fre quency sum, with the num ber of mea sure - ments of n>120, the me dian value is adopted. For mula [4] in volves the co ef fi cients f 1 and f 2 re flect ing the un even ness of fis - sure walls. The value of f 1 was dif fer en ti ated for in di vid ual geo log i cal units bas ing on field ob ser va tions of fis sure wall rough ness (see Tab. 5), whereas the value of f 2 was fixed equal at f 2 = 1.5, as sum ing that tortuosity of the fis sures is high eveywhere. To ob tain better char ac ter is tics of the hydrogeological con di tions in the Pieniny Mts., the re search was sup ple mented by test pump ing and ob ser va tions of ground - wa ter level rise in two se lected hand-dug wells lo cated on the Dunajec R. ter races. The col lected data made it pos si ble to de ter mine the ap prox i mate val ues of per me - abil ity co ef fi cients us ing the Forchheimer-Ros³oñski formula. HYDROGEOLOGICAL PROP ER TIES OF THE ROCK ENVIRONMENT Spa tial ori en ta tion of fis sures and frac tures The col lected re search ma te rial makes it pos si ble to ana lyse the spa tial ori en ta - tion of fis sures and frac tures within the four lithostrati graphic com plexes of the Pieniny Klippen Belt (Fig. 2). The most com mon ori en ta tion of the fis sures and frac tures is the SWW NEE di - rec tion par al lel to the strike of geo logic struc tures. Cre ta ceous marls and var ie gated shales, in cluded in the Jaworki Marls For ma tion (K m³ ) (Birkenmajer, 1977), show some dis tinc tions man i fested by the dom i nant SW NE and strictly W E di rec tions. In the re main ing units, these di rec tions are sub or di nate. In com pact cherty lime - stones of the Pieniny Lime stone For ma tion (JK wr ), in Ju ras sic nod u lar lime stones (Czorsztyn Lime stone For ma tion) and in crinoidal lime stones (Krupianka and Smolegowa Lime stone for ma tions) (J w ) two com ple men tary per pen dic u lar di rec - tions (NW SE and SW NE) are dis tinctly marked. The pre dom i nance of strike val - ues rang ing from 75 to 85 in flysch sand stones and shales of the Sromowce For ma - tion (K p³ ) is due to taking account of interlayer pathways while measuring. How ever, it must be pointed out that the re sults of fissurity mea sure ments pre - sented here, con cern only the up per (i.e. subsurface) zone of the mas sif. In this zone fis sures, re sult ing from weath er ing and interlayer fugues, are dom i nant. Pre sum - ably, that is why the dom i nant fis sure runs have WSW ENE di rec tion, i.e. par al lel to the ex tent of tec tonic struc tures, in stead of the ex pected NNE SSW di rec tion, i.e. along faults par al lel to the Pieniny Klippen Belt. The par al lel faults cut this geo - log i cal unit quite densely, es pe cially in the area of the Pieniny Wa ter shed (Birkenmajer, 2007), and ob vi ously play an im por tant role in ground wa ter cir cu la tion.

11 48 W. HUMNICKI Fig. 2. Orientation of fractures and fissures within selected lithostratigraphic complexes. N number of exposures; n number of fissures and fractures measured

12 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 49 Direction South North D ips of fractures and fissures in selected lithostratigraphic complexes Table 2 Angle Sandstonesand shales (SromowceFormation) K p l Variegated marlsand shales (JaworkiFormation) K m l Chertylimestones(Pieniny LimestoneFormation) J K w r Crinoidaland nodular limestones(krupiankaand SmolegowaLimestone formationsand Czorsztyn LimestoneFormation) Jw n % % n % % n % % n % % n % % Total % 70

13 50 W. HUMNICKI There fore, far-reach ing con clu sions con cern ing the im por tance for ground wa ter cir cu la tion at depth (be low the weath er ing zone) of most commonly oriented fissures are not authorized. There is a gen eral trend of nu mer i cal pre dom i nance of fis sures and frac tures dip ping south wards, most clearly ex pressed in the Sromowce For ma tion flysch (K p³ ). The only ex cep tion are nod u lar and crinoidal lime stones (J w ), where north - ward dips pre dom i nate (Tab.2). The anal y sis of data pre sented in the ta ble im plies a con clu sion that the Pieniny Mts are typ i cal of a con sid er able con tri bu tion of steep and very steep fis sures and fractures (>45 ) locally nearly vertical (>75 ), with uncommon horizontal frac - tures. This sit u a tion is fa vour able for both the amount of in fil tra tion rates and depth into to which rain wa ter can per co late. At the same time it fa vours an intensive groundwater drainage. Car bon ates De spite the rel a tively small area oc cu pied by car bon ates, they play a very im - por tant role in shap ing the Pieniny Moun tains land scape, its land forms and hydrogeological conditions. Amongst the car bon ates, the most sig nif i cant rock types are the Up per Ju ras - sic Lower Cretaceous white siliceous (cherty) limestones representing the Pieniny Lime stone For ma tion (JK wr ), and var i ous Ju ras sic lime stones in clud ing nod u lar lime stones (Czorsztyn Lime stone For ma tion), crinoidal lime stones (Krupianka and Smolegowa Lime stone for ma tions) and organogenic lime stones (J w ). Car bon ates are nat u rally prone to karst pro cesses. The hy drau lic net work in such rocks com monly in cludes three over lap ping sys tems of pores, fis sures and cav erns, as well as karst forms sec ond arily filled with clastic material. The com par i son of the re la tion ships be tween per me abil ity and wa ter stor age ca - pac ity of par tic u lar con stit u ents of the hy drau lic net work pro vides the pos si bil ity of un der stand ing mech a nisms of ground wa ter cir cu la tion and en ables us to iden tify the ground wa ter res er voir type (Krajewski & Motyka, 1999). Karst land forms are rel a tively poorly de vel oped in the Pieniny Mts. This is due to the com pli cated geo log i cal struc ture of the area that dis fa vours wa ter seep age and ground wa ter cir cu la tion, con trol ling both the dis so lu tion of car bon ates and the per ma nent sup ply of fresh wa ter un sat u rated with sol utes. Neg a tive fac tors in clude also the oc cur rence of lime stones in the form of slices and blocks, the pres ence of nu mer ous interbeddingss of karst-re sis tant rocks (radiolarites and horn stones) within the lime stones, and the iso la tion of in di vid ual blocks within low-per me abil - ity rocks such as marls, shales and claystones. All of these fac tors cause re duc tion in the ex tent of potential karst systems (Birkenmajer, 1958, 1979). The Haligovce unit in the ter ri tory of Slovakia shows slightly dif fer ent char ac - ter is tics. It is partly com posed of Tri as sic karstified lime stones, dolomitic lime - stones and dolomites (T wd ). These de pos its are ab sent in the Pol ish part of the Pieniny Klippen Belt. There oc cur also Ju ras sic karstified lime stones (J w ) and Cre -

14 Fissure opening b [mm] Surface fissure density [m/m 2 ] Fissure porosity n vs [%] GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 51 Fracturing parameters of lithologic units with reference to the classification of Liszkowski and Stochlak (eds, 1976) Class Carbonates Carbonate-clayey deposits Table 3 Flysch deposits J w LK wr K m³ K p³ n % n % n % n % <0.03 cracks very narrow narrow Criterion medium 1-2 fissures wide 2-5 wide very wide >10 extremely wide <1 very low low medium high >10 very high <0.25 practically non-fractured massif very poorly fractured poorly fractured medium fractured very strongly fractured >16 macrofractured ta ceous organodetrital lime stones (K w ) typ i cal of this unit. In for ma tion about karstification in car bon ates of the Pieniny Mts. can also be de rived from the re sults of rock-fis sur ing mea sure ments, in par tic u lar from fis sure open ing dis tri bu tion, sur face fis sure den sity and fis sure po ros ity within individual lithologic units (Tab. 3).

15 52 W. HUMNICKI Tak ing into con sid er ation the geo log i cal-en gi neer ing clas si fi ca tion of rock mas sifs (Liszkowski and Stochlak ed., 1976), it can be stated that the Pieniny Mts lime stones are the only rock type, out of four lithological types con sid ered, in which ex tremely wide-open fis sures (>10 mm) and high fis sure po ros ity were ob - served. These pa ram e ters al low to rank them among me dium fissurized (4%) or even highly fissurized (>16%) ones. Also the num ber of mod er ately wide (1 2 mm) and wide (2 5 mm) fis sures is greater in the lime stones than in other rock types. It may be re lated to both weath er ing pro cesses and the fis sures widening due to dissolution. How ever, it should be stressed that more com pre hen sive and de tailed stud ies per formed in the area of the Czorsztyn dam re vealed not only a clear re la tion ship be tween the wa ter stor age ca pac ity in car bon ates and the oc cur rence of fis sures and frac tures, but they also pro vide ev i dence that these fis sures are nu mer ous but very small (Dziewañski, ed., 1998). It is proved, among oth ers, by ex pe ri ences from grout ing works in the Dunajec River val ley while cre at ing a fil tra tion screen un der the dam body, that great wa ter stor age ca pac ity zones were sealed with a rel a tively small amount of ce ment. No in for ma tion about any voids or karst caverns is reported from this area. Karstification pro cesses in the Pieniny Mts are of a lo cal na ture and one should be very care ful in de ter min ing the hydrogeological en vi ron ment in car bon ates of the Pieniny Klippen Belt as a karst-frac tured or karstic one. In the study area, this might be only the case of some parts of the Golica-P³aœnia group in the Dunajec River Gap. While as sess ing the hydrogeological prop er ties of rocks, it is very im por tant to take into ac count the po ros ity co ef fi cient of the rock ma trix. The open po ros ity co - ef fi cient de ter mines the amount of empty spaces (pores, micropores and microfissures) in rocks, how ever re fers only to a sys tem of voids con nected with one an - other within the rock vol ume, but elim i nat ing iso lated and dis con nected pores and micropores. As these in ves ti ga tions of the rock ma trix in the Pieniny Mts are the first ones, and were car ried out to a rel a tively small ex tent, the val ues pre sented here ex hibit a lim ited rep re sen ta tive ness be cause of both scar city of sam ples from out crops and sta tis ti cally small subpopulations. Nev er the less, the re sults of lab o ra tory de ter mi - na tions of hydrogeological pa ram e ters of the rock ma trix in car bon ates in di cate low val ues of open po ros ity co ef fi cients and a very low permeability (Tab. 4). Con sid er ing the above, it is clear that the rock ma trix of the Pieniny car bon ates should be con sid ered, ac cord ing to the Pazdro and Kozerski s clas si fi ca tion (1990), as im per me able or at best as semi-per me able. It is also worth not ing that the re sults pre sented in Ta ble 4 re fer to the pos si bil ity of gas flow (ni tro gen). For free wa ter flow, the val ues will be lower, as proved by the so-called Klinkenberg cor rec tion, the value of which be ing, un for tu nately, in con stant and de pend ing on the rock fragment analysed. The oc cur rence of ground wa ter in the Pieniny car bon ates is as so ci ated ex clu - sively with a sys tem of joints that en ables the ground wa ter stor age and cir cu la tion.

16 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 53 Ta ble 4 Hydrogeological prop er ties of the ma trix of se lected lithostrati graphic com plexes Lithostratigraphic complex Sromowce Formation K p³ (N = 9) Jaworki Formation K m³ (N = 3) Pieniny Limestone Formation JK wr (N = 8) Krupianka and Smolegowa formations Jw (N = 4) Sample number Sampling site Rock type 1 Ma³y Cisowiec fine-grained sandstone Klenina calcareous siltstone/marl/ gaize Laboratory determinations Open porosity coefficient [%] n n œr Permeability coefficient [mdarcy] Estimated value of permeability coefficient [m/s] (after Pazdro & Kozerski, 1990) <0.01 < Klenina fine-grained sandstone W¹wóz Gorczyñski fine-grained sandstone 0.45 <0.01 < Kot³owy leb fine-grained sandstone Szewców Gronik fine-grained sandstone Ob³aŸna Góra fine-grained sandstone Ob³aŸna Góra fine-grained sandstone 0.80 <0.01 < Sromowce Œrednie fine-grained sandstone 0.06 <0.01 < Czerwone Ska³y marl Czerwone Ska³y marl Macelowy Potok marl/gaize 1.00 <0.01 < near Falsztyn calcareous wacke Góra Palenica calcareous wacke 0.17 <0.01 < Wierch Ska³ki Macelowy Potok (upper part) W¹wóz Gorczyñski Magierowa Ska³ka W¹wóz Szopczañski W¹wóz Szopczañski 21 near Falsztyn 22 near Falsztyn 23 near Falsztyn 24 near Falsztyn silicified micritic limestone 0.96 micritic limestone 0.08 <0.01 < calcareous wacke <0.01 < calcareous wacke calcareous wacke 0.03 <0.01 < silicified limestone/hornstone micritic grain limestone micritic grain limestone micritic grain limestone micritic grain limestone <0.01 < <0.01 < <0.01 <

17 54 W. HUMNICKI Fig. 3. Degree and type of filling of overcapillary fissures; n number of overcapillary fissures measured The cru cial role in the ground wa ter cir cu la tion and wa ter stor age ca pac ity of the rock mas sif is played by the open ing size of fis sures and the state of their filling. Fis sures in car bon ates are most fre quently filled with fairly well per me able cal - car e ous de bris and, to a lesser ex tent, with poorly per me able weath er ing ma te rial

18 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 55 Characteristics of fissure wall uneveness Ta ble 5 Fracture and fissure features Lithostratigraphic complex K p³ K m³ JK wr J w Rough [%] Smooth [%] Fissure wall unevenness coefficient (f 1) - taken for calculations (Tab. 6) represented by argillaceous loam, or, sporadically, with almost impermeable cal - cite. There are dif fer ences in the de gree and type of fill ings be tween the Pieniny carbonates (JK wr ) as well as crinoidal and nod u lar lime stones (J w ) where the ground wa ter oc cur rence conditions are less favourable (Fig. 3). There is a con sid er able vari abil ity of fis sur ing po ros ity co ef fi cients within the Pieniny car bon ates in par tic u lar out crops. It ranges from 0.03 to 21.8% with the mode value of 1 2%. A sim i lar val ues range ( %) was re ported by ukaszek and Niedzielski (1976), who based on data from bore holes drilled in con - nec tion with the Czorsztyn dam con struc tion pro ject. Bas ing on mea sure ments of wa ter stor age ca pac ity in wells, these au thors also found out that the lower depth limit of the frac tured zone en abling ground wa ter cir cu la tion lies at the maximum depth of 110 m. Fis sure po ros ity co ef fi cients of the Ju ras sic lime stones (J w ) var ied within a nar - rower range from 0.19 to 3.0%, which can also re sult from a smaller num ber of out - crops measured. Fis sur ing of lime stones is the most im por tant el e ment of the hy drau lic net work. It crit i cally af fects the pos si bil ity of ground wa ter flow. Fis sure per me abil ity co ef fi - cient is the mea sure of hy drau lic per me abil ity of frac tured rock masses. Be cause free wa ter can move only through supercapillary fis sures wider than 0.25 mm, just this value was es tab lished as the limit for fur ther cal cu la tions, ne glect ing nar rower fis sures and frac tures. In the car bon ates, supercapillary fis sures ac count for about 50% of all fis sures and frac tures (see Tab. 3). In cal cu lat ing fis sur ing po ros ity co ef - fi cients, macro-scale ob ser va tions of fis sure wall unevenness were also taken into consideration (Tab. 5) Due to the com pli cated geo log i cal struc ture of the Pieniny Mts and strong tec - tonic de for ma tion of the rock mas sif (pos si ble changes in fis sure di rec tions within the mas sif), the re sults of sur face fis sur ing mea sure ments were con tin ued to be ana - lysed not only for in di vid ual sets of strictly de fined ori en ta tions, but in an over all sense as a sys tem of fis sures pro vid ing hy drau lic con nec tions.. Fis sure per me abil - ity co ef fi cient, cal cu lated us ing these as sump tions, has an av er aged value independent of the groundwater flow direction. The cor rect ness of this me thod i cal ap proach is sup ported by re search re sults from the Czorsztyn dam area where nei ther dif fer ences in per me abil ity and dis tri -

19 56 W. HUMNICKI Table 6 Determination of fissure permeability coefficient Lithologic unit Kp³ Km³ JKwr Jw Number of exposures Number of fissures Arithmetic mean b a [mm] Mean fissure opening b [mm] Average guaranteed value(median) b m [mm] Average geometric value weighted on length b gw [mm] Mean degree of surface fissuring n F [%] Mean fissure density [m/m 2 ] coefficient Fissure permeability coefficientk [m/s] of fissure wall unevenness f 1 [-] of tortuosity of fissure system f 2 [-] f 1 f b gw formula [4] formula [5] b m b = 0.3 mm b gw b m b = 0.3 mm For mula [4] af ter Kotiachow-Johns mod i fied by Motyka & Zuber (1993) For mula [5] af ter Liszkowski & Stochlak (eds, 1976) bu tion of sat u ra tion zones be tween ver ti cal, oblique and hor i zon tal wells, nor ver ti - cal and hor i zon tal reg u lar ity in per me abil ity vari a tions of bed rock have been observed (Dziewañski ed., 1998). The re search re sults (Tab. 6) sug gest that both the Pieniny lime stones (JK wr ) and the Ju ras sic lime stones (J w ) should be con sid ered highly per me able rocks be cause of their per me abil ity pa ram e ters. How ever, these lime stones show slightly more advantageous hydrogeological parameters, their fissure permeability coefficients, cal cu lated by var i ous meth ods, ex ceed ing 10 3 m/s as com pared with m/s of the Ju ras sic lime stones (J w ). Such val ues are typ i cal of com pact rocks with a dense supercapillary fis sure and frac ture net work (Pazdro & Kozerski, 1990; Dowgia³³o et al. (ed., 2002). Re sults of fis sur ing mea sure ments in the field con - firmed the high and mod er ate den sity of fis sures in the car bon ate rocks of the

20 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 57 F ig. 4. A comparison of permeability coefficients calculated by various formulae (Tab. 6) with the values obtained by measurement s i n water wells (Tab. 1). Hand-dug wells: 1 5PieninyKlippenBelt : 1 SromowceWy ne;2 SromowceNi ne;3 Szczawnica;4 SzaflarySkiFac - t ory 1; 5 Szaflary Ski Factory2; P odhale Depression : 6 Szaflary Yoghurt Plant; 7 12 Magura unit : 7 Czorsztyn Tourist Colony; 8 Kluszkowce; 9 Czorsztyn; 10 Kroœnica Primary School; 11 Ha³uszowa Bacówka; 12 Kroœcienko Goldfruct Pieniny Klippen Belt (see Tab. 3). How ever, the ob tained per me abil ity co ef fi cient val ues are at least by two or ders of mag ni tude greater than these those re sult ing from test pump ing of wells extracting fracture water in the Pieniny Klippen Belt (Fig. 4).

21 58 W. HUMNICKI It should be men tioned here that sim i lar re la tions have been re ported from the Tatra Mts. mas sif (Barczyk et al., 1995), where, for ex am ple, the val ues of fis sure per me abil ity co ef fi cient of the Eocene num mu lit ic lime stones were also by two or - ders of mag ni tude higher than those mea sured in deep ex plor atory wells drilled in the Tatra foreland. While ana lys ing the val ues of fis sure per me abil ity co ef fi cient, one should bear in mind that the study was per formed in nat u ral sur face out crops within the vadose zone, where not only nat u ral re lax ation of the rock mass but also me chan i cal and chem i cal weath er ing pro cesses are tak ing place. Deep within the mas sif, the fis sure open ings are smaller due to the rock vol ume pres sure and de creas ing ef fect of weathering processes. This fact has a crucial significance for permeability parameters of the frac tured me dium within the sat u ra tion zone; how ever, it is prac ti cally im pos si ble to de ter mine it in the Pieniny re gion. If we as sume (af ter Lenk 1986) that a fis sure open ing has a con stant value of b = 0.3 mm, then the per me abil ity co - ef fi cients will be smaller by at least one or der of mag ni tude (and thus close to the val ues ob tained dur ing pump ing tests). They are also uni form due to the dom i nant role of the pa ram e ter b in the formulae. The fis sure per me abil ity co ef fi cient for mu lae do not in volve the de gree of fis - sure filling. Therefore, the results of calculations become overestimated. The cor - rec tion for the fis sure fill ing should be in tro duced mainly for crinoidal and nod u lar lime stones (J w ), where ap prox i mately 72% of overcapillary fis sures are filled with poorly per me able weath er ing ma te rial rep re sented by marly loam (see. Fig. 3). By us ing the for mu lae, those re sults most re sem ble the ex pected val ues (over es ti - mated, but re flect ing lith o logic vari abil ity) which were cal cu lated by the mod i fied for mula of Kotiachow-Johns and average geometric fissure opening weighted on their lenght. Sum ming up the con sid er ations con cern ing the val ues of fis sure per me abil ity co ef fi cient in the Pieniny Mts, it should be stated that the pre sented data, al though higher and over es ti mated in the zone of full sat u ra tion, could be used in the fu ture to es ti mate ground wa ter vul ner a bil ity to anthropogenic con tam i na tion from the ground surface. As sum ing (af ter Krajewski and Motyka, 1999) that the av er age val ues of open po ros ity and per me abil ity co ef fi cients are the mea sures of hydrogeological fea - tures of frac tured and po rous me dia (Tab. 7 ), it can be sug gested that the Pieniny mas sif, con sid ered in terms of con cep tual model of a hy drau lic net work in car bon - ate rocks (Motyka, 1998), is a frac tured-po rous res er voir where pores play an in sig - nificant role in the groundwater flow. The average fissure permeability coefficient is here at least by four or ders of mag ni tude higher than the av er age per me abil ity co - ef fi cient of the rock ma trix. Thus, the dom i nant role in ground wa ter flow within the car bon ate rocks is played by fis sures. The mean fis sure po ros ity of the Pieniny lime stones (JK wr ) is over three times as high as the po ros ity of their rock ma trix. In case of the crinoidal and nod u lar lime stones (J w ), the fissure and matrix porosity values are similar.

22 GROUNDWATER OCCURRENCE IN THE PIENINY KLIPPEN BELT 59 Val ues of hydrogeological pa ram e ters of hy drau lic net work el e ments Ta ble 7 Lithology Network element Parameter Carbonates Carbonateclayey deposits Flysch deposits Pore space Fissure space Open porosity of rock matrix [%] Permeability coefficient of rock matrix [m/s] Fissure porosity [%] Fissure permeability coefficient [m/s] J w JK wr K m³ K p³ Min. max average Min. <10-10 <10-10 <10-10 <10-10 Max Min. max average Min. max average , Car bon ate-clayey de pos its An ad mix ture of clayey ma te rial sig nif i cantly low ers the val ues of hydogeological pa ram e ters of car bon ate rocks. This is the case with the Pieniny s Ju ras sic mot tled marls and shales (J m³ ) and Cre ta ceous var ie gated marls and clays inter-b edded with sand stones of the Jaworki Marl For ma tion (K m³ ), which oc cupy 1/4 of the whole study area. In ves ti ga tions of wa ter stor age ca pac ity car ried out by ukaszek and Niedzielski (1976) have shown, that the pos si bil ity of ground wa ter oc cur rence in marly de - pos its is much lower as com pared to car bon ate rocks. Those au thors as sumed the lower limit of the frac tured zone within which ground wa ter cir cu la tion is pos si ble, to reach the depth of around 15 m. These ob ser va tions have been fully cor rob o rated by field re search on rock fis - sur ing. The marly de pos its are char ac ter ised by the low est fis sure den sity (4.05 m/m 2 ), the low est fis sure per me abil ity co ef fi cients ( %) and the low est per - cent age con tri bu tion of supercapillary fis sures (about 42%), while subcapillary and cap il lary fis sures are pre dom i nant). This, re sults in the low est val ues of the fis sur - ing per me abil ity coefficient (see Tabs 3, 5, 7). Tak ing also into ac count the fact that ap prox i mately 43% of supercapillary fis - sures are filled with poorly per me able marly loam or with prac ti cally im per me able cal cite, the pos si bil ity of ground wa ter flow in these rocks is very low. De spite of a mod est scale of re search, the re sults of lab o ra tory mea sure ments of rock ma trix pa ram e ters in the marly de pos its are in ter est ing (see Tab. 4). The per - me abil ity is here very low (the rock is al most im per me able), whereas the open po -