Margle krzemionkowe i fukoidowe w rejonie Rybotycz: nowe dane litofacjalne i stratygraficzne (płaszczowina skolska, kreda, Karpaty) (odpowiedź)

Stanisław Leszczyński, Mariusz Kędzierski


Leszczyński S., Malik K., Kędzierski M., New data on lithofacies and stratigraphy of the siliceous and fucoid marl of the Skole Nappe (Cretaceous, Polish Carpathians) (a reply)

Janusz Kotlarczyk (mentioned further as JK) supplied an extensive and overwhelmingly negative opinion of our paper. This opinion, in a substantial part, is based, however, on an misunderstanding of actual goal of the paper. In our paper, we did not intend, as has been suggested by JK, neither to revise stratigraphy nor sedimentology of marly units in the Ropianka Formation of the whole area of their occurrence. Our paper was prepared, as indicated in its title, key words and the introduction, to present the results of our studies on lithofacies of the Holovnia (Siliceous) Marl and Kropivnik (Fucoid) Marl units in three sections in the area of Rybotycze, and nannofossils investigation in 25 samples taken from these sections. Nannofossils were investigated there only for stratigraphie dating of selected fragments of the sections. In this respect our investigations significantly contribute to the stratigraphy of these sections (first precisely documented publication of nannofossil data from the Holovnia and Kropivnik Marl). Geological maps by JK (1978) were not used to illustrate the location of the sections discussed in our paper because of notable errors displayed in some of them (e.g., JK, this volume, fig. 1, cf., this paper, Fig. 1). Lithostratigraphy of the sections was explained in the introductory note of our paper and the publications by JK (1978, 1979a, 1985, 1988) were quoted to indicate the source data on stratigraphy of the Upper Cretaceous deposits in the area under investigation. We do not agree with the JK opinion that our data are insufficient for the characterization of lithofacies in the studied sections. The characterization is based on description and recording of all bedsets differing in the content of calcareous material in the “Wiar” and “Dolinka” sections, as well as the description of all distinctive layers in the entire “Kanion” section (2453 fining upward rhythms described) and in selected, several meters thick portions of the two other sections (792 fining upward rhythms described). Lithologie terms, as in previous works concerning these units, were based on mesoscopic determination in field and are therefore not very precise (cf., JK, 1978, 1985, 1988; Dżułyński et al., 1979 where hard marls are called calcilutites). Results of laboratory analysis of CaC03 content were presented in our paper to show real character of these rocks. All previous works that we found of significance were briefly mentioned in our paper. The paper by Gaździcka (1979, one page abstract in conference materials) was omitted because of basic biostratigraphic inaccuracies it contains and only a very general information on the source of the dated materials. We are very sorry for mistakenly quoted the dating by JK (1978) of lower limit of the Kropivnik Marl Member. Instead of Upper Campanian, as it is in our paper (p. 48), it should be Lower Campanian. All other citations of stratigraphie datating by JK are shown exactly as in his papers (see JK, 1978, 1985, 1988). As a matter of fact, the dating quoted from JK (1978) relate to the stratotype area, those from his other papers (JK, 1985, 1988) concern the whole area of the Holovnia Marl and the Kropivnik Marl occurrence in the Polish part of the Skole Nappe. It is noteworthy, that JK gives at least two different datings for one unit in the same paper (e.g., JK, 1988, cf. Leszczyński et al., 1995, tab. 1). To be honest in citation of the mentioned papers, we have decided to quote the two most probable ones. The general lithofacies characterization presented in our paper does not differ much from that one shown in the papers by JK. However, we are first recording that in the Holovnia Marl Unit noncalcareous shales (according to their reaction with HC1) occur in top of fining upward rhythms whereas exclusively calcareous shales appear to occur in the Kropivnik Marl Unit. Moreover, our investigation reveals that the basic fining upward rhythms (interpreted as turbidite/interturbidite) tend to be thinner in the Kropivnik Marl than in the Holovnia Marl unit. Contrary to JK, we consider therefore all these features significant for discriminating between both marl units. The facies distinguished in our paper were defined so as to possibly simply describe sediment variability of the examined sequences. Two classifications of heterolithic facies were used. The first one was employed to illustrate lithofacies of the entire investigated sections (Leszczyński et al., 1995, fig. 3) whereas the other classification aimed at illustrating basic differentiation of the Holovnia Marl and Kropivnik Marl Units. After introducing the latter one, we realized that it does not comprise that part of the sequence in which sandstone and that in which soft marl dominate (while hard marls are lacking). Facies of the first classification were explained in figure caption only. Their individuality was expressed in succession of rock types, that were mentioned starting from the most common ones, and in their relative proportion in the facies. This mode of facies characterization is commonly used even by JK (cf., JK 1978, ryc. 3, 4, 6). Moreover, the illustrations of the investigated sections with the help of these facies were for thr first given in our paper. They significantly differ from those presented by JK in facies pattern and therefore in ranges of particular lithostratigraphic units (cf., JK, this volume, fig. 2 -Kanion, and Leszczyński et al., 1995, fig. 3A; Kotlarczyk, Krawczyk, 1980, ris. I, and this paper, Fig. 2). It is not true that facies classifications in our paper are not correlated with each other. The facies distinguished to characterize the marl units were shown in figs. 4-6 which depict parts of the sequence indicated in fig. 3, i.e., in generalized lithofacies logs of the investigated sections. JK claims that the analysis of sediment features and their interpretations are very generalized in our paper. We realize that our paper does not answer to all possible questions concerning the sediments under consideration. Sediment features were described to the extent necessary for characterization of lithofacies. The same applies to the interpretation of the sediment origin. All characteristic, mesoscopic sediment features were mentioned Moreover, their semiquantitative frequency and relationships of particular rock type to other rocks general terms, the basic fining upward rhythms as turbidite/interturbidite, i.e., deposited from turbidity currents sensu lato. We did not document individual interturbidite layers. It were the sediments that we interpreted as interturbidites, and referred generally to pelagites/hemipelagites. We realize that the origin of these sediments may be more complex. This is indicated, for example, by the sandstone layers displaying sharp tops (called by JK tractionites). However, special detailed investigations are necessary for a more profound interpretation. Therefore we do not think that our interpretation is wrong. We dismiss the JK censure on mistakes in our nannoplankton analysis and biostratigraphy. It results from his misunderstanding and misinterpretation of our paper. We realize that the dating of our samples does not close the work on stratigraphy of the sections in question. Moreover, the results of our investigations additionally demonstrate the need for an extensive densely sampled analysis, particularly in the bottom and top part of individual Iithostratigraphic units. Such sampling procedure is necessary there because of (1) occurrence of redeposited assemblages of fossils, probably significantly older than the host bed and, (2) frequent deformation of these sequences, causing occurrence of tectonic repetitions and omission. We did not discuss Iithostratigraphic origin of the samples DI and D2 because their biostratigraphy was not clear. Moreover, they were taken from a part of the section that according to JK represents thick Holovnia Marl Unit (cf. JK, 1978, ryc. 5; JK, this volume, fig. 1). In our opinion, this part of the section (lowermost part of Dolinka) significantly differs from its description by JK (see Fig. 1). Sediment features and its contact with the Spas Shale together with the nannoplankton assemblage suggests that it represents sediments not younger than the passage from the Dolhe Formation to the Holovnia Marl Unit. We are sorry for erroneously suggesting CC 17 for the sample D7 in the table 3. This mistake was made during technical elaboration of the table. All results of our work were based on clearly indicated features that were interpreted according to the generally accepted methods. We may only agree with JK that our paper does not give final, unquestionable answers to all the problems concerning the Holovnia and Kropivnik Marl units. We resent the faithless JK opinion that we continue untrue quoting of other papers, claim the credit for the achievements of other researchers, and offer interpretations based on someone’s data. We realize that our interpretations are based on the data of different quality, and thus we are conscious of actual significance of particular interpretations.

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