VOLUMINA JURASSICA, 2020, XVIII (2): 161–234 DOI: 10.7306/VJ.18.8 The Kimmeridgian of the south-western margin of the Holy Cross Mts., central Poland: stratigraphy and facies development. Part I. From deep-neritic sponge megafacies to shallow water carbonates Andrzej WIERZBOWSKI1 Key words: Upper Jurassic, shallow-water carbonates, history of sedimentation, climatic and tectonic factors, lithostratigraphic scheme, comparison with Jura Mts., ammonite phylogeny. Abstract. The stratigraphical interval of the Kimmeridgian between the Bimammatum and the Hypselocylum zones in the SW margin of the Holy Cross Mts. shows a transition from the open shelf deep-neritic sponge megafacies to the shallow-water carbonate platform, in- cluding its development and decline. The uniform progradation of the shallow-water carbonate platform occurred at the end of the Planula Chron. Development of the shallow-water carbonate platform was controlled by climatic and tectonic factors. The former induced by or- bital cyclicity resulted in changes of sea-level, revealed i.a. by the incoming of open-marine ammonite faunas, the latter were related to the synsedimentary activity of faults which resulted in contrasted facies changes. The episodically occurring strong influx of siliciclastic mate- rial was at least partly controlled by the tectonic activity. The newly elaborated formal lithostratigraphic subdivision takes into account the facies development of the succession in relation to climatically and tectonically induced changes. Such is e.g. the Małogoszcz Oolite For- mation, corresponding to a single 100-kyr eccentricity cycle from the late Platynota Chron to the earliest Hypselocyclum Chron, bordered from the base and top by two transgressive climatically-controlled levels. The final stage of the shallow-water platform development at the end of the Hypselocyclum Chron was marked by the successive limitation of restricted environments, and the appearance of more open- marine conditions related to tectonic subsidence of the area of study. Comparison between the carbonate platform development of the Holy Cross Mts. in central Poland, and the coeval shallow-water carbonates of the Jura Mts. in northern Switzerland and south-eastern France provides an opportunity to consider similarities in the successions which can be attributed to the climatically-controlled sedimen- tary cyclicity and/or the wide-ranged tectonic phenomena. The palaeontological part of the study gives comments on the classification and phylogeny of ammonites of the families Ataxioceratidae and Aulacostephanidae. INTRODUCTION Maastrichtian and during the Palaeocene (Kutek, Głazek, 1972). The Jurassic actually preserved, including the Kim- The Kimmeridgian deposits occurring at the margins of meridgian deposits which are discussed here, in the south- the Holy Cross Mountains represent remnants of the Juras- western, the north-western and the north-eastern margins of sic cover developed originally over the whole area of the the Holy Cross Mts., differs partly in the completeness of its mountains, including its Palaeozoic core, but subsequently succession, and in type of its facies (see e.g. Kutek, 1968, partly removed due to Neo-Cimmerian (pre-Albian), and es- 1969, 1994; Gutowski, 1992, 1998; Matyja, 2011; Matyja, pecially Laramian tectonic movements at the end of the Wierzbowski, 2014). There are also regional differences in 1 University of Warsaw, Faculty of Geology, Żwirki i Wigury 93, PL 02-089 Warszawa, Poland; [email protected]. 162 Andrzej Wierzbowski the style of the tectonic deformations (Kutek, Głazek, 1972). stratigraphically markedly below the base of the Kim- The Jurassic deposits in the south-western margin are folded meridgian as interpreted formerly, and thus below the up- and usually dip gently at a few up to 20° , but are locally permost Oxfordian correlated with a part of the Planula steeply inclined or even vertical, at the limbs of the relative- Zone, as interpreted in the south-western margin of the Holy ly densely spaced anticlines and synclines generally stretch- Cross Mts. by Kutek (1968). The Kimmeridgian, as accept- ing in a NW–SE direction (see e.g. Kutek, 1968, fig. 1). ed herein, includes also a part of the older deposits occur- The aim of this study is to present a general outline of ring in the south-western margin of the Holy Cross Mts., the stratigraphy, facies development and history of sedimen- correlated with the Planula Zone and the Bimammatum tation of the Kimmeridgian in the south-western margin of Zone (down to the base of the Bimammatum Subzone) de- the Holy Cross Mountains. The first attempt to classify scribed by Matyja (1977) and Matyja et al. (1989). On the lithostratigraphically the Kimmeridgian deposits (referred at other hand, the succession of the youngest deposits of the that time to the “Astartian” and “Kimmeridgian”) in the area Kimmeridgian in the south-western margin of the Holy was made by Świdziński (1962). The “facies-lithological Cross Mts. is not complete, although it ranges through the complexes” described by him roughly correspond to the Mutabilis Zone and at least a part of the Eudoxus Zone of herein distinguished formations. The classical study of the the lower part of the Upper Kimmeridgian. This is because Kimmeridgian deposits of the south-western margin of the of the pre-Albian erosion of the youngest Jurassic (and the Holy Cross Mts., their stratigraphy and palaeogeography, oldest Early Cretaceous deposits) due to the Neo-Cimmeri- was presented by Kutek (1968, 1969) with lithofacies de- an tectonic movements in that area (Kutek, 1968, 1994). scriptions supplemented by Pszczółkowski (1970). Although This paper is devoted to the Lower Kimmeridgian de- becoming the most comprehensive description of these posits from the open shelf deep-neritic sponge megafacies to rocks in the area, some of the interpretations given therein the succeeding shallow-water carbonate facies in the south- nowadays need modification. This results from general pro- western margin of the Holy Cross Mountains. These repre- gress in detailed ammonite stratigraphy, such as the appear- sent the fragments of the transgressive-regressive sequence ance of the new stratigraphical subdivisions of the Kim me- recognized in the territory of Poland by Kutek (1994) as the ridgian based on the evolution of the ammonite family COK (Callovian-Oxfordian-Kimmeridgian) sequence. The Ataxioceratidae (Atrops, 1982), but also because of the shallow-water carbonate deposits of the regressive part of opening of new extensive quarries, including e.g. the ce- the sequence are considered as representative of the shallow- ment-works quarry at Małogoszcz, which have provided water carbonate platform, which is regarded herein as a zone large collections of ammonites and offered new data on the of shelf covered by carbonate deposits formed above or close facies development and interpretation of the palaeogeogra- to wave base (cf. Matyja et al., 1989, p. 34). When com- phy (see e.g. Matyja et al., 2006a). pared with holistic problematics of the carbonate platform The Kimmeridgian, as treated herein, corresponds to the deposits in south-eastern Poland, including the stratigraphi - stratigraphical interval from the base of the ammonite Bay- cal interval from Middle Oxfordian to Lower Kimmeridgian, lei Zone in the Subboreal zonal scheme (and the correspond- the subject of this study as related to the Lower Kimmeridg - ing Bauhini Zone in the Boreal scheme), which is the base ian from the Bimammatum Zone to the Hypselocyclum Zone of the uniform Kimmeridgian Stage as proposed by the in the south-western margin of the Holy Cross Mts. only, is Kimmeridgian Working Group and recently accepted by the limited in its extent. Nevertheless, because of good expo- International Subcommision on Jurassic Stratigraphy of the sures, long history of investigation and fairly abundant ammo- International Union of Geological Sciences. This boundary, nites, the studied Lower Kimmeridgian succession provides corresponding to the base of the ammonite Bimammatum an ideal opportunity to discuss also some general concepts Zone (and the base of the Bimammatum Subzone) in the concerning the development of the discussed shallow-water Submediterranean zonal scheme, runs markedly lower than carbonate platform. The overlying uppermost Lower and lo- the formerly accepted lower boundary of this stage in the wermost Upper Kimmeridgian deposits formed after the de- area of study (and in the Submediterranean Province as cline of the shallow-water platform, mark the beginning of a whole). In consequence of such a stratigraphical interpre- the next transgressive-regressive sequence LUK (Lower- tation, the deposits of the Submediterranean Planula Zone, Upper Kimmeridgian) (Kutek, 1994), and will be described sep- and the Bimammatum Zone, previously correlated with the arately, in the second part of the study, published elsewhere. Upper Oxfordian, become included in the Kimmeridgian The present study includes the area from the southern- Stage (see Matyja et al., 2006b; Wierzbowski A. et al., 2016, most occurrences of the Kimmeridgian deposits at Korytni- 2018). The present study thus treats the Kimmeridgian Stage ca and Celiny, and north-eastwards up to Bukowa quarry, according to the actually proposed uniform European (and Gruszczyn, Rogalin and Oleszno (see Kutek, 1968; world-wide) definition with the base of the stage ranging Pszczółkowski, 1970; see also Figs. 1, 2). This area repre- The Kimmeridgian