Palaeoenvironmental changes recorded in the oxygen and carbon isotope composition of Kimmeridgian (Upper Jurassic) carbonates from central Poland

Abstract

Palaeoenvironmental changes re corded in the ox y gen and car bon iso tope com po si tion of Kimmeridgian (Up per Ju ras sic) car bon ates from cen tral Po land. Geo log i cal Quar terly, 63 (2): 359-374,

Seismic Characteristics and Development of the Upper Jurassic Carbonate Buildups from the Miechów Trough (Southern Poland)

“…1300 m within the area presently located beneath the Miocene Carpathian Foredeep basin, located South from our study area (e.g., [16,[18][19][20]100]). Recent studies allowed for more precise dating of the Upper Jurassic succession, and the redefinition of some lithostratigraphic units (e.g., [21,[101][102][103][104][105]).…”

“…The Oxfordian-lowermost Kimmeridgian (from upper Transversarium-Bifurcatus up to the Planula Zones; cf. [19,103,105]) was a time of extensive growth of microbial-sponge carbonate buildups (bioherms) in various areas within present-day central and southern Poland (cf., [27,28,68,69,92] and references therein). The Oxfordian-Lower Kimmeridgian (up to the Planula Zone) microbial-sponge and coral deposits represent mid ramp facies, which in the lower Kimmeridgian (Platynota-Hypselocyclum zones) were replaced by inner ramp oolitic and oncolitic facies (e.g., [19,70,91,100,103,105,106,[113][114][115]).…”

“…[19,103,105]) was a time of extensive growth of microbial-sponge carbonate buildups (bioherms) in various areas within present-day central and southern Poland (cf., [27,28,68,69,92] and references therein). The Oxfordian-Lower Kimmeridgian (up to the Planula Zone) microbial-sponge and coral deposits represent mid ramp facies, which in the lower Kimmeridgian (Platynota-Hypselocyclum zones) were replaced by inner ramp oolitic and oncolitic facies (e.g., [19,70,91,100,103,105,106,[113][114][115]). The evolution of the Oxfordian-Lower Kimmeridgian mid ramp facies into the Lower Kimmeridgian inner ramp facies resulted from the general shallowing trend in sedimentary conditions, observed progressively from E, NE and N, i.e., from the present-day Holy Cross Mountains area towards the present-day Miechów Trough (e.g., [16,18,19,70,91,100,105]; Figure 1).…”

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

“…The deposits of the Sobków Oolite Member accumulated over a large shoal, the outer margins of which migrated in time possibly towards the west and south-west (Kutek, 1969). Relatively scattered oxygen and carbon isotope values suggest considerable variations in water temperatures and salinity resulting from fresh water influx and an enhanced evaporation rate along with changes in the input of terrestrial organic matter (Wierzbowski, 2019). Nevertheless, although of shallow-marine origin, when compared with the discussed underlying shallow-marine deposits of the Małogoszcz Oolite Formation, they show marked differences.…”

“…The successive replacement of the Rasenia faunas by the Pachypictonia (and related Pomerania) faunas along the Submediterranean migration route was possibly related to heterochronic changes reflecting successive adaptations of the aulacostephanid migrants to the distant, highly unstable environment of the shallow-water carbonate platform (cf. Wierzbowski, 2019). The concentration of ammonites at the top of the Sobków Oolite Mbr.…”