O wieku pstrych margli we fliszu Karpat Zachodnich

Marian Książkiewicz

Abstract


On the age of variegated marls in the Flysch of the Western Carpathians

In a paper (21) on the structure of the Lanckorona zone, in the unit which appears in tectonic windows from beneath the Silesian nappe, the present writer distinguished a series composed of marls and variegated shales. The unit was defined at that time as «the upper parautochthonous nappe». The marls were described as bluish or greenish, in places red, soft and spotted. As they repose directly upon the gaizes-beds, they were considered as capping them normally. In the mentioned paper the exact age of the marls was not determined; because of their position over the gaizes-beds, regarded at that time as the Upper Cretaceous, I felt inclined to assign them to the Palaeogene (21, p. 305). Shortly after the paper on Lanckorona had been published, I discovered a Barremian-Aptian fauna in sandstones interbedded in gaizes-beds and in consequence a lower age should have been ascribed to the gaizes-beds and to the covering marls. Therefore, I presumed in another paper (16) that the variegated marls and shales probably represented the middle and possibly the upper part of the Cretaceous. I emphasized in that paper that the marls together with the underlying gaizes-beds form a separate tectonic unit, which I defined with the local name of the Woźniki nappe; this nappe builds a large overthrust sheet at Woźniki in the foreland of the Silesian nappe and also appears in the windows of the Lanckorona zone within the area occupied mostly by the Silesian nappe (16). The view as to Cretaceous age of the marls in the year 1936 was not strongly supported by the evidence available at that time. That view has been based on the following facts: 1) at Jastrzębia near Lanckorona the undoubtedly Middle Cretaceous gaizes-beds pass gradually into the marls; 2) between Lanckorona and Jastrzębia, and south of Woźniki, the variegated marls rest directly upon the gaizesbeds and may be regarded as the normal stratigraphical cover of the latter. In both areas, however, i. e. at Lanckorona and south of Woźniki, the tectonics is so greatly complicated that the second argument in favour of Cretaceous age of the marls could not be regarded as fully ascertained. Furthermore, some observations made in the years 1937—1938 seemed to deny the supposition of Cretaceous age of the marls. Near Sułkowice, east of Lanckorona, I observed very similar marls, connected stratigraphically with the Menilite beds which, as it is generally known, are of Upper Eocene age. Besides, in the area between Żywiec and Sucha during the mapping of the sheet Babia Góra, I found thick complexes of variegated marls among beds, the age of which was unquestionably Eocene. These variegated marls exhibit no differences in comparison with the presumably Cretaceous marls of the Woźniki nappe. These facts seemed to indicate that at least a part of the variegated marls in the Lanckorona zone may also belong to the Eocene. Another fact also threw a shadow of doubt as to the Cretaceous age of the variegated marls. J. Grzybow sk i (17) described and figured in 1896 a rich foraminiferal fauna, collected in the red marls at Wadowice. The fauna was determined by him as of Lower Oligocene age. The marls were collected from a shaft at present not accessible any more, but the samples have been preserved in the collections of the Department of Geology of the University of Cracow, and could be compared with the marls of the Woźniki series. The lithological resemblance to the discussed marls is complete. During the war, however, the fauna was revised and determined as representing the Upper Cretaceous (19). But the doubts evoked by the given above observations caused that in the edition of the Wadowice sheet in 1939 the variegated marls of the area, with a single exception of the marls at Jastrzębia as passing gradually into the gaizes-beds, were assigned to the Palaeogene (presumably to the lowest division of that stage). The recent results both of field work (H. Świdziński 34, H. Teisseyre 35) and micropalaeontological research (H. Hiltermann , 19) on the related Węglówka marls in the Central Carpathians, for long time regarded as belonging to the Eocene, have shown that those marls correspond to the Upper Cretaceous and revived the author’s interest in the problem of the age of the variegated marls in the Western Carpathians. The discussion and interpretation presented in this paper are based both on the field studies and micropalaeontological examination, accomplished during the years 1947—1949 within the area of the sheets «Wadowice» and «Babia Góra» in the Western Carpathians. I. OCCURRENCE AND DIVISION OF MARLS The marls in question occur in three belts: 1. In a belt running from Radocza on the Skawa river through Woźniki to Zygodowice; to this belt belong also marls appearing in an isolated point near Grabie (north of Kalwaria). The marls of this belt occur along the northern border of the Silesian nappe. 2. Another belt with the variegated marls runs through the localities Barwałd-Kalwaria-Lanckorona-Sułkowice. Here the marls appear from beneath the Silesian nappe in narrow tectonic windows. The marls from the Wadowice shaft (to-day not visible) and a small outcrop at Targanice lie in the westward prolongation of this belt. In either belt the marls do not occur in continuous bands but form small fragments and sheets, being strongly compressed and torn away by the overthrust of the Silesian nappe. Often they are folded with the overlying older beds, e. g. with the Barremian Wierzowice shales, and tne folding is so intimate that the marls seem to be simple intercalations in these beds. In 1936, the true relation of these beds was, however, discerned (16). 3. The third zone of the variegated marls lies within the area occupied by the Krosno beds of Upper Eocene — Oligocene age. These beds overlie the Silesian Cretaceous. The variegated marls are known from the following localities: Łękawica, Ślemień, Kocoń (Babia Góra sheet); similar position is occupied by the marly shales at Krzeszów and Stryszów (Wadowice sheet). Micropalaeontological examination proves that the marls in the first belt belong to the Cretaceous, the marls of the second belt mostly to the Cretaceous and merely a small portion of those marls must be assigned to the Eocene, while the variegated marls of the third zone are exclusively of Eocene age. The tectonic position indicates that the marls of the first and second belt appertain to a unit which is lower than the Silesian nappe; that unit, previously determined as the upper parautochthonous nappe or the Woźniki nappe, nearly everywhere underlies the Silesian nappe and therefore, it seems, may more fittingly be defined as the «Subsilesian nappe». The marls of the third belt, situated at the top of the Silesian Cretaceous, belong to the Silesian nappe. Thus in the Western Flysch Carpathians three complexes of marls may be separated: 1. the Cretaceous marls of the Subsilesian series; 2. the Eocene marls of the Subsilesian series; 3. the Eocene marls of the Silesian series. II. CRETACEOUS MARLS OF THE SUBSILESIAN SERIES 1. S itu a tio n and lith o lo g y In most cases the base of the marls is unknown or they lie upon younger beds, e. g. upon the Eocene Ciężkowice beds of the External Flysch, which forms the lowest tectonic unit in the Western Flysch Carpathians. Only south of Woźniki and at Jastrzębia is the normal base, constituted by the gaizes-beds, visible. The gaizes-beds have recently been divided into two complexes, separated by black shales with exotic blocks and Orbitolinae1. The lower complex is related to the Hauterivian sandstone, while the upper gaizes-beds represent the Aptian and at least a part of the Albian, being an equivalent of the Lgota beds in the Silesian series. South of Woźniki in the stream Rędzina and at Jastrzębia the upper gaizes-beds are covered directly by the variegated marls. The contact between the gaizes and marls is exposed but in one place, in the stream-bed of the Jastrzębia, south of the village. This place will be named henceforth «Jastrzębia-village». The series is here inverted and the marls dip below the gaizes. The overturning is marked not only by the sequence, but also by the position of hieroglyphs situated on the upper surfaces of beds and by the inverted graded bedding. The marls are greenish, white on weathering, consisting of alternating hard and soft layers with not infrequently interbedded thin gaizes. As the marls contact here directly with the gaizes and contain gaizeslayers, they must be regarded as the lowest member of the marly succession. At Jastrzębia-Kopań and in the stream Rędzina the marls cap the gaizes, but the direct contact is not exposed there, although the distance from the marls exposures to the gaizes is not great. Therefore the marls of Jastrzębia-Kopań and Rędzina may be regarded as situated near the top of the gaizes-beds. In both places the marls are mostly green or bluish-green when wet, slightly fissile and spotted, rather soft, with subordinate layers of red marls resp. red marly shales. The red colour appears in the green beds also as spots and irregular streaks. On the contrary, the red marls exhibit numerous green spots; this gives them a mottled appearance. The lithological type of marls such as observed at Jastrzębia and in the Rędzina stream is dominating in the series of the marls and therefore it may be termed as «normal». In most exposures (Targanice, Barwald, Bugaj, Ubionka, Bachowice, Grabie) this type is represented. A different type of marls may be observed in the stream Gościbia near Sułkowice. In a small tributary, running into the Gościbia stream, grey, hard marls alternating with marly shales are exposed. The beds are white on weathering. Dark streaks resembling fucoids are characteristic of these marls. Traces of similar marls are visible also at Bugaj. Their extension in the area is at any rate small. The relation of the marls of Gościbia to the marls previously described is unknown, as nowhere are these two types of marls in direct contact. At Bugaj the marls of the Gościbia type occur in the direction of dip of the normal marls; this may lead to the inference that the former are younger than the latter. Another type of marls has been recorded from Radocza (north of Wadowice). The marls are here hard, grey or greyish-green, evenly bedded with intercalations of green or red marly shales and containing flints. Also in this case no relation to the variegated marls could be established. From the above it may be concluded that the following lithological types of marls may be established: a) Hard green marls of Jastrzębia-village, b) Green and red soft marls of the «normal» type, c) Hard white marls from Gościbia, d) Marls with flints from Radocza. In no place is the cover of the marls of stratigraphical character. At Targanice the marls dip along a tectonic plane under the Palaeocene of the Andrychów Klippen series. At Radocza the marls support the Lower Cretaceous Grodziszcze sandstones, in the Rędzina — the Grodziszcze beds or the Wierzowice shales, at Grabie are folded together with the Barremian Wierzowice shales; in the Lanckorona belt they are brought into contact either with older beds (Lower Cretaceous), which are thrust over them, or with the younger strata, overlying them also along abnormal contacts. Only at Radocza the marls are surmounted by sandstones of the Ciężkowice type (Eocene); unfortunately the exposures here are very poor and there is no certainty that the sequence is continuous. 2. Microfauna The marls are rich in foraminifera, especially the normal (b) marls and the marls of- Radocza (d), while the marls of Gościbia (c) and particularly the marls (a) of Jastrzębia-village are rather poor in microfauna. In all the kinds of marls two types of foraminiferal fauna may be distinguished, one composed of calcareous and another of agglutinated foraminifera. To the first type the following genera belong as the most numerous in the foraminiferal assemblage of the marls: Globotruncana, Giimbelina, Globigerina, Flabellina, Frondicularia, Robulus-Lenticulina, Nodosaria, Dentalina, Glandulina, Lagena, Globulina, Discorbis, Gyroidina, Eponides, Cibicides, Pseudotextularia, etc. The agglutinated forms, are represented by: Gaudryina, Clavulina, Ammodiscus, Glomospira, Rhabdamina, Reophax, Saccammina, Rzehakina, Textularia, Verneuillina, Cyclammina, Trochammina, Spiroplectammina, Arenobulimina, etc. Besides foraminifera the marls contain abundant ostracoda and fish teeth, and sometimes also radiolaria. In the green marls the calcareous foraminifera dominate over the agglutinated; in extreme cases this predominance leads to a complete elimination of agglutinated forms as is the case at Grabie where the foraminiferal assemblage of green marls is composed in 1/3 of Globigerina, in 1/3 of Globotruncana and Giimbelina and the rest is composed of other calcareous foraminifera with solely a few arenaceous forms. In the red marls, on the other hand, the agglutinated foraminifera are slightly predominating over calcareous forms or the amount of both is approximately equal. Globotruncana, Globigerina and Giimbelina occur only in green marls, except at Targanice where Globotruncana appears also in red marls. From the above it may already be concluded that the marls should be attributed to the Cretaceous. Numerous Globotruncana, Globigerina cretacea, Globigerinella aspera, Giimbelina globosa, Reussella szajnochae, Pseudotextularia, Verneuillina abbreviata, and abundant Flabellina point to an undoubtedly Upper Cretaceous age. Another proof is found in fibres and fragments of Inoceramus which in places are fairly frequent. A more accurate age of the marls may be determined on the basis of Globotruncana, the significance of which for a more detailed stratigraphy has recently been emphasized from many sides (Viennot 38, 39, Thalmann 37, Vogler 40, Glaessner 14, Bolli 3, etc.). Globotruncanae are abundantly and widely distributed in the marls, particularly in their normal type. In some places they are very abundant as is the case at Jastrzębia-Kopań and in the stream Rędzina, where more than a half of the foraminiferal assemblage belongs to this genus. At other points they are less numerous or occur very sparingly but in no sample of green marls are they absent. With reference to the determination of Globotruncanae some difficulties should be underlined. Modern works, introducing the separation of Globotruncanae into several subspecies or creating new species, are based in many cases merely on the axial sections (Vogler, Bolli). I have to my disposition washed material and the foraminifera separated from the rock are as a rule well preserved but no axial section could be prepared. Therefore the identification of Globotruncanae from the soft marls of the Western Carpathians to a certain extent has been handicapped. Among Globotruncanae from the marls the forms with two keels are much more numerous than those provided with a single keel. The two-keeled Globotruncanae correspond perfectly to the form described by J. de Lapparent (26) as Rosalina linnei d’Orb. from the Pyrenees. A few types connected by passages may also be discerned alike in the Pyrenean material. These types correspond to some of the types («mutations») distinguished by Lapparentt. It is generally known that the generic name Rosalina has been replaced by Cushman with the name Globotruncana. In 1936 B ro tz en (4) noticed that the type and mutations of Rosalina linnei described by J. Lapparent do not correspond to the original Globotruncana («Rosalina») linneiana d’Orbigny and there fore called Lapparent’s form Globotruncana lapparenti. In spite of some opposing views (Glaessner 14, Gandolfi 13), the name introduced by B ro tz en has recently been used by Bolli (3) in his remarkable paper on Alpine Globotmncanae; this author has given several new reasons for separation 6f Gl. lapparenti from the original type of Orbigny. Two-keeled Globotruncanae from the Wadowice area for the greatest part exhibit sutures on the ventral face not disposed radially, but because the chambers are overlapping on each other, they are curved forward. Therefore the contour of chambers visible from the ventral side is not round but appears more or lfess compressed. These features according to B ro tz en and Bolli characterize Globotruncana lapparenti {—Rosalina linnei of Lapparent) and discern this species from the similar Gl. linneiana d’Orb, Gl. canaliculata Reuss, Gl. marginata Reuss and Gl. ventricosa (White) Brotzen with a round contour of chambers on the ventral side and radial sutures. Globotruncana lapparenti Brotzen had been divided by Lapparent (25, 26) into several mutations, which lately have been regarded as subspecies, after Yogler (40) defined with two specific names. Among Globotruncanae from the Wadowice area the following types could be distinguished (plate III). Globotruncana lapparenti lapparenti Bolli. Test with flattened both dorsal and ventral faces, parallel or nearly parallel to each other; the spiral face at most feebly convex. Chamber walls of the last whorl flat on both sides, more flat on the dorsal face. The periphery of the whorl truncated with a broad band provided with thick and distinct, usually beaked keels parallel to each other. The peripheric band perpendicular to both faces. Horizontal contour lobate, perpendicular contour nearly rectangular. This form corresponds very well to type 1 of Lapparent (Gl. linnei typica of Yogler) and may be determined after Bolli as Globotruncana lapparenti lapparenti. It occurs rather sparingly in the normal marls (b) and in marls (a) of Jastrzębia-village. I found it at Jastrzębia- Kopań, where it is rather abundant, at Grabie and Barwałd. Globotruncana lapparenti tricarinata Quere au. Test slightly less flat than in the precedent form, the dorsal side forming a flat cone. The peripheric band broad with two distinct beaded keels. Below the lower keel the chamber walls hang down, being not perpendicular to the band and flat but obliquely inclined toward the umbilicus, and terminated with a third keel. This keel is connected in a narrow and compressed arch with the lower keel of the peripheric band. The hanging down of the chamber walls is more strongly marked in the last chambers. Between this and the previous form exist transition types, in which the chambers on the ventral face are flat and the ventral face perpendicular or nearly perpendicular to the peripheric band; near the umbilicus, however, the third keel is always more or less distinct. It may easily be identified with Globotruncana lapparenti tricarinata Quereau. This form is one of the most abundant in the Wadowice area. Very frequent in normal marls at Jastrzębia-Kopań, Barwałd, Rędzina, fairly frequent at Grabie and Targanice, a few specimens have been collected at Bugaj. It also occurs, but not numerously, in the marls of Gościbia (c) and Radocza (d). Globotruncana area Cushman. Test markedly biconvex, on the spiral face more or less conical. Chambers from the ventral side are somewhat rounded, and flat from the dorsal side. The peripheric band is low with two beaded but not very distinctly marked keels, which are not parallel to each other. The band is somewhat inclined toward the umbilicus. On the ventral side sutures are curved, but in the last chambers their arch is not very strongly bent forward and sutures are arranged nearly radially. The identification of this form is rather difficult. The low band indicates that the form may be related to type 4 of Lapparent, which is flat or subconical and possesses «bandeau carénai réduit». On the ventral side, however, the bend of chambers is not so advanced as in type 4, where it forms «une couronne de feuilles imbriquées» ; this refers particularly to the last chambers. This form seems to correspond to Globotruncana linnei marginata (Reuss) as described by Vogler, to which this writer assigns type 4 of Ros. linnei of Lapparent, together with Globotruncana area of Cushman and Globotruncana marginata Reuss. This has been questioned by Gandolfi; according to him the forms described by Vogler correspond to Gl. linnei var. angusticarinata Gandolfi. Our specimens, because of their biconvexity, approach to the latter form, but keels do not contact with each other. The discussed form seems to be very similar to Globotruncana area Cushman (1926, original description according to the catalogue of Ellis-Messina 12, and especially forms described and figured by Glaessner (14) from the Caucasus but not Gl. area Cushman 1932, 7), being biconvex, markedly conical on the dorsal side and possessing a not very wide band. Nevertheless in some cases it is very difficult to separate it from Gl. lapparenti lapparenti, as there exist transitional forms between these two species as mentioned by Glaessner (14). Possibly this form, because of passages to GL lapparenti and curved sutures on the ventral side, should be termed Gl. lapparenti area. This form is very frequent in normal marls (b) and together with GL lapparenti tricarinata may be regarded as the most common. Very abundant in the Rędzina stream, it is also represented at Targanice, Barwałd, Bugaj, Grabie and in the Ubionka stream. Globotruncana cf. lapparenti coronata Bolli. Tests flat, thus resembling typical GL lapparenti lapparenti, but strongly compressed; therefore both keels he close to each other, forming seemingly one keel. Upper and lower chamber walls slightly rounded. Chambers as seen from the ventral face compressed but enlarged forward, likewise as mutation 4 of Lapparent. Keels situated near each other remind of Gl. linnei var. angusticarinata Gandolfi, but that form is biconvex, while the discussed form is flat. It resembles particularly Gl. marginata Reuss as described and figured by J. G. Egger (10), but Egger’s figure does not correspond to the drawing of Reuss from the year 1854 (32) which is considered by Brotzen as typical of Gl. marginata Reuss. It seems that this form approaches best GL lapparenti coronata Bolli with elongated and low chambers and a reduced inter-keel band. This reduction according to B olli may attain the stage in which keels are in close contact. According to Sigal (33) Gl. lapparenti coronata Bolli and Gl. linnei var. angusticarinata Gandolfi correspond to each other. Our forms, possibly corresponding to a more compressed GL lapparenti lapparenti, may provisorily be determined as GL cf. lapparenti coronata Bolli. It is fairly frequent in the normal marls (b) from the Rędzina stream and green marls (a) from the Jastrzębia-village. Globotruncana leupoldi Bolli (—GL rosetta Carsey?). Specimens differing from the preceding types in shape and possessing only one keel on the last chambers, which is in some specimens not very distinct. On the first chamber of the last-formed whorl a lower feeble keel is sometimes visible, united with the upper one. The spiral face is subconical or (in smaller specimens) flat; on the contrary, chambers on the ventral side are hanging down; it is why their contours are conical. This is particularly strongly pronounced in the last two chambers. There exist a few forms already described which possess these characteristics: Rosalina linnei mutation a loges coniques of Lapparent, Globotruncana linnei pendens Vogler, Globotruncana linnei stuarti Vogler, Globotruncana leupoldi Bolli and Globotruncana rosetta Carsey. The first is described as type 5 of Rosalina linnei with spiral face flat or even concave, chambers hanging down and one keel formed by the union of two visible on earlier chambers. Similar forms are described by Vogler as Gl. linnei stuarti, which have been regarded by him as transitory between Globotruncana linnei (=lapparenti) and stuarti. In this subspecies two-keeled forms and those provided with one keel are united, therefore Bolli distinguished among the sections figured by Yogler two groups: one with internal whorls possessing one keel and external chambers with double keel and another group characterized by double keel in internal chambers and single keel in the last whorl. The second group has been determined by Bolli as a separate subspecies Globotruncana leupoldi, corresponding to the mutation a loges coniques of Lapparent. It should, however, be mentioned, that previously Glaessner (14) had noticed that type 5 of Lapparent corresponds to Gl. rosetta Carsey. Glaessner’s paper was not known to Bolli (he does not quote it in his references), and, generally, this writer does not make any references to the American species of Globotruncanae, what naturally might be done only after comparison with original specimens or topotypes. Nevertheless one can notice a great resemblance between the discussed form and Gl. rosetta Carsey. Another form. which must be taken into consideration in the identification of this form is Globotruncana stuarti Lapparent, the vertical outline of which is alike that of discussed specimens. The horizontal contour, however, of the Carpathian specimens is typically lobate and not rounded as in Gl. stuarti, the difference underlined by Lapparent (26). Our specimens in their vertical outline approach the figures of Vogler, which Bolli regards as corresponding to Gl. leupoldi, and particularly to the form figured by Lapparent (26), p. 13, fig. 5 d. On the contrary they are less similar to forms drawn and photographed by Bolli; those forms are much more conical on the spiral face than the Carpathian specimens (and also than the specimen of Lapparent). Therefore, considering the contour, chambers hanging down and flat spiral face, I feel certain that this form corresponds to type 5 of Lapparent, i. e. to Globotruncana leupoldi Bolli resp. Gl. rosetta Carsey. This form occurs very sparingly in normal marls (b); single specimens have been found in the Rędzina, at Jastrzębia and Targanice; it is much more frequent in the white marls (c) of Gościbia. Glo b o t runc ana aff. conica White. A different shape is exhibited by Globotruncana, which is strongly conical on the dorsal face and flat or nearly flat on the ventral side. The cone is not pointed, but somewhat rounded. Near the base of the cone a slight peripheric keel is visible; another keel, still more feebly marked lies, already on the ventral face. Chambers seen from the ventral side seem to be more elongated than in the precedent forms. The vertical outline indicates that the described form corresponds to type 6 of Rosalina linnei as described by Lapparent and defined as «mutation caliciforme». Vogler named it Gl. linnei caliciformis (de Lapparent). According to Bolli this form should be separated from Globotruncana conica White. The latter, according to the original description (taken from the Catalogue of Ellis and Messina) is a single-keeled Globotruncana. On the figures of Lapparent (26, fig. 2, j. and plate I, fig. 2) two keels situated near each other are visible and the third near the umbilicus is also marked. Similar forms are described by Glaessner (14) as cf. conica; this writer surmises that the forms determined as mut. caliciforme may belong either to Gl. conica White or to Gl. contusa Glaessner (= G l . area var. contusa Cushman). Kikoine(20) regards mut. caliciforme as corresponding to Gl. conica, but some recent French workers use simply the determination: Gl. caliciformis. Our form differs from Gl. conica by elongated chambers and their smaller number in the last-formed whorl. Gl. conica has 8 chambers, while in our specimens only 6 may be seen, except one specimen in which 8 chambers occur in the last-formed whorl. It seems that some individuals may be regarded as intermediate between GL area and the discussed form. The Carpathian specimens correspond to type 6 of Lapparent and I think that the best way will be to determine them provisionally as Globotruncana aff. conica White, until the relation of mutation caliciforme to Gl. conica White is elucidated. This species occurs very sparingly in normal marls (b), collected from the Rędzina, Grabie, Targanice and Jastrzębia in small specimens. Larger specimens have been found in the marls of Radocza (d). Globotruncana stuarti Lapparent. I possess a few specimens of Globotruncana, the test of which is very similar to Gl. leupoldi, i. e. the dorsal side is slightly subconical, the ventral side convex and hanging down and the chambers seen from the ventral side — conical. A single keel is visible. However, the horizontal contour is not lobate but continuous and rounded. This feature is, according to the description and figures of Lapparent (26), characteristic of Globotruncana stuarti. Lapparent has distinguished two mutations of this species: one larger with pointed spiral face and another nearly flat. Our specimens belong to the second mutation. It occurs in the Radocza marls (d), accompanied by small forms approaching GL leupoldi; they may be underdeveloped individuals of Gl. stuarti, because Lapparent remarks that young specimens of Gl. stuarti possess the appearance of the mutation «a loges coniques » of Ros. linnei. A few specimens exhibit rounded horizontal contour but the chambers on the spiral side are not rectangular but somewhat elongated; they may be transitory forms between Gl. stuarti and leupoldi. Globotruncana aff. margina ta Reuss. Contour of the test resembles much that of Globigerina cretacea, but the form is somewhat larger and provided with two very feebly marked peripheric keels. It is very similar to Globotruncana globigerinoides Brotzen (non Marie 1941). From the form of Brotzen it differs by its slightly flattened dorsal side; this causes the chambers to be asymmetrical, inflated on the ventral and flattened on the dorsal side. Umbilicus large, the number of chambers in the last whorl 5—6. Sutures on the ventral side arranged radially; this indicates that the form does not belong to Globotruncana lapparenti Brotzen. The interrelation of chambers is different than in Globotruncana ventricosa White, from which it also differs by the much narrower peripheric band and keels only Very slightly marked. The radial arrangment of sutures on the ventral side and inflation of chambers is similar to those of GL marginata Reuss; also the narrow band with two feeble and approaching keels resembles that form. Taking all this into consideration one may conclude that the form is related most to Globotruncana marginata Reuss (1854), from which it differs only by slightly less flattened chambers on the dorsal side. It may be allocated between GL globigerinoides Brotzen and GL marginata Reuss or perhaps between Gl. ventricosa Brotzen and GL marginata Reuss but in both cases approaches more GL marginata than the other species. It has therefore been determined as Globotruncana aff. marginata Reuss. It occurs only at Bugaj in normal marls (b) in a few individuals. The determined Globotruncanae from variegated marls of the Wadowice area belong thus to the species or subspecies listed below: Globotruncana lapparenti lapparenti Bolli, Globotruncana lapparenti tricarinata Quereau, Globotruncana cf. lapparenti coronata Bolli, Globotruncana area Cushman, Globotruncana leupoldi Bolli (=G L rosetta Carsey?), Globotruncana aff. conica White, Globotruncana stuarti Lapparent, Globotruncana aff. marginata Reuss. Their distribution in particular types of marls and principal localities of the Wadowice area is given in table I (p. 351). The Cretaceous marls in the Western Carpathians nowhere offer opportunity of studying zonal distribution of foraminiferal faunas in one continuous cross-section. The marls are squeezed into narrow bands in which only subsequent valleys are developed. Therefore no attempt could be made to establish a succession of particular species of Globotruncanae in the marls; to precise the age of marls successions established in other regions would have to be used. Recently such successions have been recorded from the Pyrenees (26), Appenines (31), Alps (3, 13), Caucasus (14) and even from the Malayan archipelago (40). Although numerous cases of Globotruncanae have been recorded from the Eocene (recently comp. Micropaleontologist, III, 4, 1949), after Viennot, Thalmann and others these foraminifera may safely be regarded as Cretaceous index fossils when they occur abundantly and in a variety of forms. In the marls of the Western Carpathians the first place is occupied by double-keeled Globotruncanae. They are usually regarded as Turonian and Senonian, but the problem is not yet sufficiently cleared up as a few instances of Globotruncana with double keel have been recorded in the Middle Cretaceous (Aptian, Albian). In the Appenines and Alps* Globotruncana lapparenti B ro tz en (=linnei auct.) appears abundantly at the beginning of the Turonian. It seems safely to compare the Carpathian sediments with the beds comprising Globotruncana in the Alps as there is little room for doubt that the Carpathian geosyncline was a simple prolongation of the Alpine one. Therefore we base our conclusions mainly on the results obtained recently by Gandolfi (13) and Bolli (3). In the Alps Globotruncanae appear in the Albian (13) and Cenomanian as single-keeled forms, so far not yet found in the Western Carpathian variegated marls1. The double-keeled GL lapparenti appears a little above the base of the Turonian, and typical Gl. lapparenti lapparenti lasts throughout the Turonian up to the base of the Maestrichtian,. while the accompanying Gl. lapparenti tricarinata enters also the Maestrichtian. Gl. lapparenti coronata Bolli occurs in the upper part of the Turonian, Coniacian and Santonian, Gl. leupoldi Bo lli in the Campanian and Maestrichtian, while Gl. stuarti Lapp, is restricted to the Maestrichtian. GL marginata Reuss occurs in the Upper Turonian, Coniacian, Santonian, and Campanian. GL cónica so far has not been described from the Alps; in the Pyrenees (Rosalina linnei mut. caliciforme) together with GL stuarti occurs in the Maestrichtian. According to M a rie (27) this species in the Mediterranean region appears in the Campanian and characterizes mainly the Maestrichtian. Likewise Gl. area Cushman is restricted to the Campanian and Maestrichtian (14). If we accept the identity of GL leupoldi Bolli with GL rosetta Carsey, we must take into consideration the vertical distribution o f the last named species. In America it is known from the Turonian up to the Maestrichtian inclusively although it is more numerous in the upper portion of the Upper Cretaceous. In the Caucasus, however, according to Glaessner (14), it is restricted to the Campanian and Maestrichtian. From this vertical distribution of Globotruncana the following conclusions may be made: Marls with flints from Radocza (d), containing Gl. aff. conica and Gl. stuarti, belong to the Maestrichtian. The presence of Gl. lapparenti tricarinata excludes the uppermost Maestrichtian. White marls of Gościbia (c) containing abundantly Gl. leupoldi and Gl. lapparenti tricarinata may represent the upper Campanian or even the Maestrichtian. The normal marls (b) contain as a rule Gl. area and a small admixture of Gl. aff. conica and Gl. leupoldi; all these three forms are essentially characteristic of the Campanian and Maestrichtian. Typically Maestrichtian Gl. stuarti is, however, absent, and the presence of Gl. lapparenti lapparenti at Jastrzębia-Kopań, Barwałd, Grabie and of Gl. aff. marginata at Bugaj seems to indicate that the normal marls are older than the Maestrichtian. In these localities the marls are probably of Campanian age, probably corresponding to its lower part, as Gl. aff. conica, in the upper portion of the Campanian usually already abundant, is in them extremely rare. The occurrence of Gl. cf. lapparenti coronata in the Rędzina stream seems to prove that here the marls belong to a very low zone of the Campanian if not to the Santonian. In the green marls (a) of Jastrzębia-village only Gl. lapparenti lapparenti and Gl. cf. lapparenti coronata are present. No Campanian forms are represented, what may indicate their pre-Campanian age; on the basis of Globotruncana lapparenti lapparenti one may say that they are not older than the Turonian and not younger than the Campanian. We know that they represent the lowest member of the marl series and very likely they are somewhat older than the variegated marls. The absence of one-keeled forms characterizing the Cenomanian and the presence of Globogerina cretacea d’Orb., which according to Glaessner (15, p. 206) appears for the first time in the Turonian seem to support the view that they are not older than the Turonian. A limitation, however, should be made in connection with the possibility of occurrence of such double-keeled forms as Gl. lapparenti also in the Middle Cretaceous. Thus we may regard: a) The green marls of Jastrzębia-village as corresponding possibly to the Turonian or the Lower Senonian, b) the normal variegated marls as belonging to the Lower Campanian, c) the white marls of Gościbia as of Upper Campanian age, d) the marls with flints from Radocza as representing the Lower or Middle Maestrichtian. It will be a task of future research to complete and possibly to modify this determination of the age of the marls with the help of other micro-foraminifera. In the meantime we may add that at present there exist additional arguments supporting the determined age of the marls. The marls, particularly the red marls, contain such species as Verneuillina (Reussella) szajnochae Grzyb, which is considered as an Upper Senonian index fossil (Campanian-Maestrichtian, cf. Glaessner 15). It occurs abundantly at Grabie (in green marls), Rędzina (green marls), Jastrzębia (frequent in green, very abundant in red marls), Ubionka (frequent in red, rare in green marls), Targanice (fairly frequent in green, very abundant in red marls). In the marls of Radocza (d) large forms of Pseudotextularia from the varians group can be met with; they are regarded as index foraminifera for the Maestrichtian (Marie 28, Glaessner 15,. p. 207). It is necessary to draw certain conclusions with regard to the age of the gaizes beds underlying the marly series. They were regarded by the present writer as corresponding to the Upper Aptian-Albian. If we correlate the marls (a) from Jastrzębia-village with the Turonian, we must consider the gaizes series as corresponding not to the Middle Cretaceous alone but also to the Cenomanian. As it was said above, nowhere is the normal top of the marly series exposed directly in immediate contact with the marls. From the determination of the age of the marls given above and the regional distribution of marls one may suppose that the sandstones of Szydłowiec with abundant bryozoans and lithothamnia discovered by the present writer (22) and containing a foraminiferal assemblage determined by Prof. F. Bieda (2) as of Maestrichtian age, form a member succeeding the marls of the Subsilesian sequence. Another possibility, however, should be borne in mind; these sandstones may represent a littoral facies of the Maestrichtian in relation to the Radocza marls. 3. Cempar i son with other beds containing Globotruncana in the Ca rpa thian Flysch The determination of the age of the discussed marls as Turonian- Senonian indicates that the marls may be considered as an equivalent of the Istebna beds, which on the ground of a very sparingly occurring macrofauna are regarded as representing the Senonian and possibly the Turonian. In the Wadowice area, and, generally, in the Western Carpathians,, the microfauna of these beds is not yet sufficiently known. On the basis of a few samples one may say that the foraminiferal fauna is much poorer, composed almost exclusively of agglutinated forms. In one cross-section, however, in the vicinity of Wola Radziszowska and Leńcze (SW of Skawina), above the red Middle Cretaceous shales near the base of the Istebna beds a few intercalations of somewhat more marly strata have been discovered by the present writer; the marls contain an abundant foraminiferal assemblage, composed mostly of calcareous foraminifera with Globotruncana, Globigerina cretacea, G/o bigerinella aspera, Nodosaria, Dentalina and numerous Rotaliidea, Arenobulimina, etc. Among Globotruncanae the first place is occupied by abundant Gl. area Cushman (1926) and besides the following species have been found: Gl. leupoldi Bolli (Leńcze, very rare), Gl. ventricosa Brotzen and Gl. globigerinoides Brotzen (both at Wola Radziszowska). Globotr. ventricosa (PI. Ill) with spheric chambers and wide band between two distinct keels corresponds fairly well to the type figured by Brot zen, 4, fig. 63, 2. In Europe Gl. ventricosa does not cross upward the Santonian; its presence together with Gl. globigerinoides and GL area seems to indicate that the marly Istebna beds of Wola Radziszowska and Leńcze may represent approximately passage beds from the Santonian to the Campanian. At any rate, the presence of these Globotruncana in the Istebna beds indicates that they cannot differ much in age from the variegated marls, being possibly at their base slightly older. The upper parts of the Istebna beds may be thus safely regarded as equivalent to the variegated marls. Below the Istebna beds occur the Godula beds, in part developed as variegated shales, and the problem may arise whether they also are an equivalent to the variegated marls. Such a comparison was borne in mind by the present writer in 1936 (16), when, only on the ground of their position, a Middle and Upper Cretaceous age was ascribed to the variegated marls. The comparison of microfauna, however, does not seem to confirm that view: the agglutinated microfauna of the Godula red shales is entirely different from the assemblage of the variegated marls. There is little room for doubt that the Węglówka marls in the Central Carpathians are equivalent to the discussed marls. The lithology and the situation are much the same; the Węglówka marls overlie the Węglówka sandstones which according to the observations of the present writer, to a considerable extent are composed of typical gaizes. Recently J. Czernikowski(8) claims that in the marls he found Globotr. apenninica Renz and Gl. linneiana d’Orb. (probably GL lapparenti Brotzen) and on this ground and on the presence of a basal zone containing Arenobulimina this author regards the Węglówka marls as representing the Albian, Cenomanian and Turonian. It is necessary, however, to point out that the presence of GL linneiana is in any case insufficient for limitation of the upper age boundary of the Węglówka mai;ls to the Turonian as it is generally known that this species occurs also in the Senonian up to the base of the Maestrichtian. In the Eastern Carpathians (Roumania) the marls with Globotruncana are known inside the Flysch belt (29). It is striking that these red marls occur in a very much similar tectonic position as in the Western Carpathians, i. e. as sheets under an overthrust. Outside the Flysch Globotruncana occurs abundantly in the marly or calcareous rocks of the external Klippen at Andrychów (22) and in the exotic blocks at Bachowice; it is well known that it also occurs in the red marls of the Pieniny (1, 23), but no further comparison with those deposits can be made at the present stage. II. EOCENE MARLS OF THE SUBSILESIAN SERIES In the vicinity of Sułkowice (sheet Wadowice) small areas are occupied by grey-greenish marls, white on weathering, somewhat harder than normal variegated marls, with calcite veins. A few bands of red marly shales are interbedded. There is no doubt that those marls, at least in the Gościbia stream, are passing upward into the silex complex of the Menilite beds; this implies their Eocene age. They appear in a tectonic window between the Silesian and Magura nappe and lie on direct extension of the variegated marls of the Lanckorona zone. The foraminiferal assemblage is entirely different from that of the variegated marls described in chapter I. The forms characteristic of the variegated marls are absent. Species of Spiroplectammina, Gaudryina, Trochammina and Ammodiscus are dominating, calcareous forms are but few. In the Gościbia stream just below the Menilite silexes Cyclammina amplectens Grzyb., characteristic of the middle part of the Eocene of the Central Carpathians, occurs abundantly. III. VARIEGATED EOCENE MARLS OF THE SILESIAN SERIES In the longitudinal basin situated south of the Cretaceous of the Little Beskid, in the villages Łękawica, Ślemień and Kocoń the variegated marls occur, forming long belt inside the Krosno beds (Upper Eocene-Oligocene) which fill the basin. These marls are so similar to the normal marls (b) described in chapter I, that one may easily regard them as lithologically identical. The grey-greenish marls are also prevalent here, while those of red colour are rather subordinate; the red marls are usually mottled, this being due to green streaks and stains. A slight difference may be seen in their fissility; the discussed marls are somewhat more compact and harder than the variegated marls of the Cretaceous sequence. This is easily noticed when washing; the Cretaceous marls may be washed partly without soda while the washing of the Eocene marls necessarily requires using soda. Also here, however, parts of softer marls may appear. The position of marls alone does not assist much in the interpretation of their age. They are covered in most cases directly by the Krosno beds and only in one place traces of the Menilite beds could be discovered in the intervening position. Nowhere is their normal base exposed; as a rule they are thrust over the Krosno beds, forming cores of scaled and overturned folds. As they are lacking in the normal sequence of the Silesian Eocene, exposed farther to the north of the occurrences of variegated marls, one might presume that they represent a more southern facies of the Silesian Eocene. It should, however, be stressed that in the vicinity undoubtedly Cretaceous marls appear in the tectonic window of Żywiec. The question of the age of the variegated marls is unequivocally decided by their microfauna. The samples collected from several points situated between Żywiec and Sucha contain an abundant microfauna. This is not so diversified as the assemblages of the Cretaceous variegated marls, but the quantity of individuals is equally considerable. Calcareous forms predominate; like in the Cretaceous marls, the number of calcareous foraminifera is larger in green than in red marls. A characteristic element of the microfauna is represented by Globigerina. In an extreme case their number amounts to a half of the foraminiferal content. They belong mostly to two species: Globigerina bulloides d’Orb. and Gl. triloba Reuss. The former has not been found in the Cretaceous marls although Grzybowski quotes it from Wadowice and the latter is very infrequent in the Cretaceous marls. No Gl. cretacea or neither GL aspera have been found in the marls in question. The family Discorbinae is represented by several forms, o f which characteristic although not very frequent Gyroidina soldani d’Orb. may be mentioned. Other calcareous foraminifera do not play any great part (Nodosaria, Lagena, Dentalina, etc.). Agglutinated foraminifera occur very sparingly (Ammodiscus, Trochammina, Glomospira, Cyclammina) but they furnish a very characteristic Cyclammina amplectens Grzyb, and Reophax pilulifera Brady. The abundance of Globigerina indicates that the variegated marls may be correlated with the Globigetina zone, distinguished already by Grzybowski (18) in the Central Carpathians. Recently it has been worked out by W. Pożaryski (30), according to whom it is characterized by a mixed fauna. The lithological development is, however, different in comparison with the variegated marls of the Żywiec area, as in the Central Carpathians the Globigerina fauna with an admixture of agglutinated foraminifera occurs in green shales of the Hieroglyphic beds or in white marls. Similar white marls also occur in the Wadowice area in the Silesian series just below the basal silexes of the Wadowice area (near Lanckorona) and contain plentiful Globigerina. It seems that they correspond to the Globigerina zone of the Central Carpathians, while the variegated marls of Ślemień, Kocoń, etc. represent a somewhat deeper zone reaching the acutidorsata zone of the Central Carpathians. This view seems to be corroborated by the presence of Cyclammina amplectens Grzyb, in the variegated marls which is closely related (if not identical) to Cyclammina acutidorsata Hantken. This form occurs much below the Globigerina zone, as it can be seen from the table of Pożary ski. It seems to be necessary to add that eastward from the described Eocene variegated marls in an identical position, instead of marls, red shales (marly to a certain extent) occur (Krzeszów, Stryszów). The microfauna is composed mostly of large Trochammina', Textularia costidorsata and Glomospira charoides are very frequent. The presence of Rzehakina epigona in that assemblage indicates that this must be a deeper zone, approaching the base of the Eocene. FINAL REMARKS The variegated marls with an abundant planctonic fauna represent a sediment of different character in comparison with the Flysch deposits among which they are situated. This indicates that the Carpathian sea attained in certain regions and certain periods a stage when no Flysch sediments could be deposited. The variegated marls may to a certain extent be compared with «calcschistes planctoniques» occurring in the Alps (36) and surmounted by Flysch deposits. It is noteworthy that this type of sediments migrates in time from one region (Cretaceous of the Subsilesian series) to another (Eocene of the Silesian series).

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