Geo log i cal Quar terly, 2016, 60 (1): 252–255 DOI: http://dx.doi.org/10.7306/gq.1265
Fos sil karst in the Ju ras sic of the Koœciuszko Mound in Kraków (south ern Po land):
dis cus sion
Ireneusz FELISIAK1, *
1 AGH Uni ver sity of Sci ence and Tech nol ogy, Fac ulty of Ge ol ogy, Geo phys ics and En vi ron men tal Pro tec tion, al.
A. Mickiewicza 30, 30-059 Kraków, Po land
Felisiak, I., 2016. Fos sil karst in the Ju ras sic of the Koœciuszko Mound in Kraków (south ern Po land): dis cus sion. Geo log i cal Quar terly, 60 (1): 252–255, doi: 10.7306/gq.1265
Wójcik et al. (2015) wrote that pre-Qua ter nary fill ings of the karst cav i ties in the Ju ras sic lime stones be neath the Koœciuszko Mound are Up per Cre ta ceous and Mid dle Mio cene ma rine sed i ments. How ever many al ready pub lished facts ne - glected by the Au thors as well as crit i cal anal y sis of their pa per makes their con clu sions highly du bi ous.
Al though the drillings stud ied by Wójcik et al. (2015) aimed, i.a., to rec og nize the geo log i cal struc ture be fore des ig na tion of a tun nel on “Zwierzyniecka Route”, the au thors ne glected three bore holes drilled along the pre lim i nary course of the tun nel, i.e., 550 metres east ward from the Koœciuszko Mound. Drillings T1, T2 and T3 (com pleted in 1975 by the HYDROGEO Co.) were marked in the map pub lished by Felisiak et al. (2005: fig.1) cited by Wójcik et al. (2015). A part of the orig i nal map from Felisiak et al. (2005) is pre sented as Fig ure 1, only the names of the bore holes were sup ple mented. Strati graphic sym bols of sed i - ments un der ly ing the Qua ter nary strata were left un changed, even if some have be come out dated. The Mio cene marls and the oys ter lime stones, in cluded pre vi ously into the Karpatian, are re cently in ter preted as sed i ments of the first phase of Badenian trans gres sion (Pilarz and Olejniczak, 2013).
The green clays known from the T3 bore hole, be long to the de pos its of the mid dle level of pre-mid-Mio cene (Oligocene–Early Mio cene?) karst (Felisiak, 1992), fill ing sub-Mio cene karst val leys. Such a best-rec og nized palaeovalley was found in un der ground work ings of the Matylda Zn-Pb ore mine in Chrzanów (Panek and Szuwarzyñski, 1976), which en abled its unique 3D re con struc tion. The 3 kilo metres long val ley had in cised down to nearly 70 m into the Tri as sic car bon ate for ma tion at the west ern mar gin of the Kraków Up - land. The val ley was filled with the re sid uum left af ter karstification of the Ju ras sic lime stones, and by the Mio cene oys ter lime stones (as in the T3 bore hole; Felisiak, 1992: fig. 3).
The hor i zon tal karst con duits at the bot tom level of the val ley are con nected with the sed i ment-filled sink holes lo cated in the
up per, gen tle slopes of the val ley. In Kraków, the sed i ments of the mid dle level of pre-mid-Mio cene (Oligocene–Early Mio - cene?) karst are lo cated at the el e va tion of 180–230 metres a.s.l., sim i larly to those iden ti fied by Wójcik et al. (2015) as fill - ings of pre-Qua ter nary, hor i zon tal caves. These facts dem on - strate that data from the T1 to T3 bore holes must be taken into ac count if any one at tempts to ex plain the or i gin of karst fea tures in the nearby G1 to G4 bore holes.
All sam ples of green ish-grey clay with cal car e ous de bris (be low named briefly “the green ish-grey clay”) are marked Crm
– Maastrichtian in fig ure 3, though the only one quoted as Maastrichtian in the text orig i nates from the 2G bore hole (depth 63.9 m). In that sam ple, the au thors iden ti fied four taxa of ge nus rank and two spe cies of foraminifers (ta ble 1), from which the only one suit able for age de ter mi na tion seems to be Abathomphalus mayaorensis (Bolli). How ever, this is a Tethyan spe cies, which has not been iden ti fied in Po land out of the Carpathians (Dubicka and Peryt, 2012). Fur ther more, pho to - graphic doc u men ta tion of this microfossil is more than in suf fi - cient be cause it lacks the most char ac ter is tic, ven tral side and the side view (Wójcik et al., 2015: fig. 5B). Un doubt edly, Campanian is the age of fauna iden ti fied in a sam ple col lected from the 1G bore hole at 18.8 m depth, also marked as Maastrichtian in fig ure 3, but left uncommented on in the text.
The fauna as sem blage in cludes the foraminifer Globorotalites michelinianus (ta ble 1), which points out to a strati graphic in ter - val not youn ger than the Mid dle Campanian (Inoceramus tenuilineatus Zone; Peryt and Dubicka, 2015). More over, this foraminifer was de rived from sed i ment lo cated higher in el e va - tion than above-men tioned Abathomphalus mayaorensis (Bolli) and clos est to the ero sional top sur face of the Ju ras sic for ma - tion. It sug gests de po si tion of Maastrichtian clay deeply in the lime stone mas sif through karst con duits filled yet with Campanian sed i ment. The au thors wrote (p. 68) that the Maastrichtian green ish-grey clay does not con tain sand in spite of the youn ger karst sed i ments de scribed in the lit er a ture (Gradziñski, 1962; Felisiak, 1992). How ever, the ab sence of sand ad mix ture in the green ish-grey clay is very un usual be - cause sand frac tion is a typ i cal com po nent of true Maastrichtian ma rine rocks (Jurkowska, 2016).
* E-mail: felisiak@geol.agh.edu.pl
Received: September 8, 2015; accepted: November 13, 2015; first published online: December 3, 2015
The cross-sec tion (Wójcik et al., 2015: fig. 4) was drawn in a man ner that sup ports the pre-Badenian age of faults; thus, the bot tom sur face of the Mio cene for ma tion is drawn to tally flat un - der the Rudawa River val ley, where no ob ser va tions could be made, and is cut through by the faults. More over, the faults cut also the Qua ter nary strata in ter races of the Vistula and Rudawa rivers on both sides of the Lasek Wolski Hill. Such po - si tion of the faults is in con flict with, i.a., nu mer ous out crops of Mio cene lit to ral struc tures and oys ter lime stones (Felisiak et al., 2005: fig. 1). Their pres ence proves that the re cent foot hills of the Las Wolski Hill rep re sent mostly the un cov ered rocky coast - line from be fore 11 Ma. This prob lem has al ready been dis - cussed by D¿u³yñski (1953) and by Radwañski (1968: 415) who il lus trated his con cept with a mean ing ful pho to graph (Plate II) of
the Vistula River bed seen in the south-east cor ner of the study area. How ever one sec tor of the cross-sec tion drawn by Wójcik et al. (2015: fig. 4) dif fers sig nif i cantly, just in the area of land - slide in Spadzista Street, where the au thors gained more field ob ser va tions. Be tween Królowa Jadwiga Street and the 1G bore hole in fig ure 4, Mio cene clays – clearly youn ger than the fault – are de pos ited onto the strongly in cised top sur face of faulted Ju ras sic lime stones.
Wójcik et al. (2015: 68) con sider two po ten tial pro cesses of for ma tion of karst con duits, ear lier than Paleogene. The first,
“clas sic” con cept calls the subaerial con di tions that oc curred gen er ally in the Early Cre ta ceous. The au thors ig nore the rule that the karst con duits, be ing in con nec tion with the Earth sur - face (open up ward), like other de pres sions of the ter rain, must Fossil karst in the Jurassic of the Koœciuszko Mound in Kraków (southern Poland): discussion 253
Fig. 1. Geological map of the St. Bronis³awa Hill after Felisiak et al. (2005; modified)
have been filled with sed i ments at the lat est at the be gin ning of the trans gres sion. In the Kraków area, such con duits were filled with the well-known Cenomanian and lat est Turonian?/Early Coniacian con glom er ates (Ko³odziej et al., 2010). The old est Santonian and Campanian sed i ments have never filled the ver - ti cal fis sures pen e trat ing through the top of the Ju ras sic for ma - tion in a way ob served in Cenomanian con glom er ates (cf.
Felisiak, 1995a; Ko³odziej et al., 2010). More over, at the lat est since the Campanian, the whole study area was suc ces sively cov ered by marly sed i ments of the re cent thick ness up to 50 m (Rutkowski, 1993: bore hole no. 20). De spite these facts, Wójcik et al. (2015) claim that “Karst chan nel fill ing might have oc - curred dur ing the Late Cre ta ceous sub mer gence (Campan - ian–Ma astrich tian)”.
The sec ond for ma tion pro cess of the karst con duits prior to the Paleogene could be the sub ma rine karst de vel oped in the mix ing zone of fresh and sa line wa ters along the coast line.
How ever, the for ma tion of karst con duits re quires the hy drau lic gra di ent, i.e., the rocky coast built of Ju ras sic lime stone must have been at least sev eral metres high whereas the au thors need cliffs at least 100 m high, as re vealed by their fig ure 3. The au thors do not pro vide the age of this karst. Gradziñski (1962:
480) con cluded that “At the end of the Ju ras sic and dur ing the Cre ta ceous the lack of larger el e va tion drops does not fa cil i tate the de vel op ment of large-scale karst cir cu la tion”, and I con sider this opin ion still valid as it is con sis tent with the re al i ties of Me - so zoic stage of geo log i cal evo lu tion of the Kraków area.
CONCLUSIONS
1. The green ish-grey clay with cal car e ous de bris fill ing karst cav i ties re corded by Wójcik et al. (2015) is not Late Cre ta ceous ma rine sed i ment. There is no ev i dence that Maastrichtian sed i - ments were de pos ited with an onlap/over lap un con formity di -
rectly upon a Ju ras sic bed rock, which was sug gested by Wójcik et al. (2015).
2. The green ish-grey clay with cal car e ous de bris does not cor re late strictly with the green clays with flints known from the T3 bore hole. In stead, this clay prob a bly cor re sponds to some - what youn ger, fresh wa ter green and grey clays grad ing lat er ally into marls and caliche-type lime stones be long ing to the (for mer) Karpatian (Felisiak, 1995b). Com mon fea tures of these sed i - ments are: col our, ab sence of sand frac tion, marly char ac ter (fa cil i tat ing redeposition of micro fauna) and Santonian-Cam - pan ian age of the source rocks.
3. Microfossils iden ti fied within grey cal car e ous silts in di cate high vari abil ity of depositional en vi ron ment, typ i cal of oys ter lime stones (see Radwañski, 1968). Grey cal car e ous silts orig i - nate prob a bly from redeposition of fine-grained frac tion of these de pos its. The silts were de pos ited through subhorizontal con - duits which were partly cleared of the clays dur ing a short up lift of the study area be tween the first and the sec ond phase of Badenian trans gres sion. The in fill ing might have taken place dur ing the rise of ero sional base caused by the ap proach ing sec ond phase of the trans gres sion.
4. The subhorizontal caves de scribed by Wójcik et al.
(2015) per fectly doc u ment the depth of the pre-Badenian palaeovalley of the Rudawa River. The val ley is in cised into the Ju ras sic lime stones down to at least 100 m depth, i.e., 10 m deeper than Felisiak (1992) could doc u ment in the Zabierzów area. Again, the stud ies con firmed the prin ci ple of Gradziñski (1962: 475) con cern ing the or i gin of caves in the Kraków Up - land: “..the de vel op ment of caves and the in ci sion of val leys must have been roughly con tem po ra ne ous“.
Ac knowl edge ments. Sin cere thanks are due to Ms.
Z. Dubicka for her kind as sis tance in rec og niz ing the de tails of micro fauna iden ti fi ca tion and in selectiing a num ber of ref er - ences con cern ing the Late Cre ta ceous micro fauna. The re - search was fi nanced from the AGH-UST Grant No.
11.11.140.626.
254 Ireneusz Felisiak
Fig. 2. Cross-section of the St. Bronis³awa Hill along the preliminary course of the tunnel of “Zwierzyniecka Route”, 550 m east of the Koœciuszko Mound
¿,pQp – Pleistocene alluvial deposits; ¿ – conglomerates, s – sands; other explanations as in Figure 1
REFERENCES
Dubicka, Z., Peryt, D., 2012. The Lower/Up per Maastrichtian bound ary in ter val in the Lublin Syncline (SE Po land, Bo real Realm): new in sight into foraminiferal stra tig ra phy. News let ters on Stra tig ra phy, 45: 139–150.
D¿u³yñski, S., 1953. The or i gin of the Up per Ju ras sic lime stones in the Cra cow Area (in Pol ish). Acta Geologica Polonica, 3:
325–440.
Felisiak, I., 1992. Oligocene–early Mio cene karst de pos its and their im por tance for rec og ni tion of the de vel op ment of tec ton ics and re lief in the Carpathian Fore land, Kraków re gion, South ern Po - land (in Pol ish with Eng lish sum mary). Annales Societatis Geologorum Poloniae, 62: 173–207.
Felisiak, I., 1995a. Nep tu nian dykes of Bonarka – a tes ti mony of the Late Cre ta ceous tec tonic move ments in the Cra cow Up land – dis cus sion (in Pol ish with Eng lish sum mary). Przegl¹d Geologiczny, 43: 869–872.
Felisiak, I., 1995b. Sedymentacja i³ów l¹dowych i caliche w rejonie Krakowa (in Pol ish). In: Tradycja a nowoczesnoœæ w interpretacjach sedymentologicznych (eds. M. Doktor, A.
G³uszek, D. Gmur and T. S³omka): 68–69. Materia³y Konferencyjne IV Krajowego Spotkania Sedymentologów Polskiego Towarzystwa Geologicznego, Kraków.
Felisiak, I., Matyszkiewicz, J., Soko³owski, T., 2005. Teach ing of geo log i cal map ping at Geo log i cal Map ping De part ment, AGH Uni ver sity of Sci ence and Tech nol ogy, Kraków. Przegl¹d Geologiczny, 53: 899–902.
Felisiak, I., Krajewski, M., Matyszkiewicz, J., 2008. A 4. Litologia i tektonika wapieni górnojurajskich rejonu Krakowa (in Pol ish). In:
Przewodnik sesji terenowych (ed. G. Haczewski): 39–45.
Pierwszy Polski Kongres Geologiczny, Kraków, 26–28 czerwca 2008.
Gradziñski, R., 1962. Or i gin and de vel op ment of sub ter ra nean karst in the south ern part of the Cra cow Up land (in Pol ish with
Eng lish sum mary). Rocznik Polskiego Towarzystwa Geologicznego, 32: 429–492.
Jurkowska, A., 2016. Inoceramid stra tig ra phy and depositional ar - chi tec ture of the Campanian and Maastrichtian of the Miechów Synclinorium (south ern Po land). Acta Geologica Polonica, 66:
59–84.
Ko³odziej, B., Szulc, J., Machaniec, E., Kêdzierski, M., Duda, M., 2010. In jec tion dykes as ev i dence of Campanian synsedimentary tec ton ics on the Kraków Swell, south ern Po - land. Annales Societatis Geologorum Poloniae, 80: 285–301.
Panek, S., Szuwarzyñski, M., 1976. Pre-Tortonian val ley with Ter - tiary fill near Chrzanów (in Pol ish with Eng lish sum mary).
Rocznik Polskiego Towarzystwa Geologicznego, 46: 503–523.
Peryt, D., Dubicka, Z., 2015. Foraminiferal bioevents in the Up per Campanian to low est Maastrichtian of the Mid dle Vistula River sec tion, Po land. Geo log i cal Quar terly, 59 (4): 814–830.
Pilarz, M., Olejniczak, P., 2013. New data on age of oys ter lime - stones – Wola Justowska out crop (Mio cene, Kraków area, Carpathian Foredeep, Po land). 14th Czech-Slo vak-Pol ish Palaeontological Con fer ence and 9th Pol ish Micropalaeontological Work shop. Ab stracts Vol ume: 43–44.
Radwañski, A., 1968. Lower Tortonian trans gres sion onto the Miechów and Cra cow Up lands (in Pol ish with Eng lish sum - mary). Acta Geologica Polonica, 18: 387–445.
Rutkowski, J., 1993. Objaœnienia do Szczegó³owej Mapy Geologicznej Polski 1:50 000, arkusz Kraków (973) (in Pol ish).
Pañstwowy Instytut Geologiczny, Warszawa.
Wójcik, A., Garecka, M., Olszewska, B., Wódka, M., 2015. Fos sil karst in the Ju ras sic of the Koœciuszko Mound in Kraków (south - ern Po land). Geo log i cal Quar terly, 59 (1): 61–70.
Fossil karst in the Jurassic of the Koœciuszko Mound in Kraków (southern Poland): discussion 255
