Stratygrafia raf raurackich w okolicach Bałtowa
Abstract
STRATIGRAPHY OF THE RAURACIAN REEFS IN THE VICINITY OF BAŁTÓW
Summary
The author discusses stratigraphy of the Rauracian deposits occurring in the vicinity of Bałtów. Basing on the rich palaeontological data, the author confirms the accepted Rauracian age of coralliferous series and of subordinately spongeous organogenic deposits, which are present in the vicinity of Bałtów. On the basis of the ammonite fauna found in this area, the author tried to parallel the subdivision of Malm into Oxfordian, Rauracian, Astartian etc., applied in Poland, with the standard ammonite zones of the Upper Jurassic, by W. J. Arkell. This attempt gave the results concerning only the upper Oxfordian (Argovian) and Rauracian. Unfortunately, one could not uniformly determine the boundary between the Epipeltoceras bimammatum zone (Rauracian after the French and Polish authors) and the Streblites tenuilobatus zone (Astartian after the French and Polish authors). Simultaneously, the author states that the previously accepted boundary between the Rauracian and the Astartian, determined only on the lithological basis and supported by the ammonitic fauna, should be considerably removed upwards, because in this series, regarded up to now as being of Astartian age, the Oxfordian ammonite forms have been found there.
The author also pays attention to the necessity of revising the stratigraphical significance of the gastropod fauna of the Ptygmatis genus. This fauna regarded till present for an important stratigraphical element of the Astartian, appears at Bałtów in the Rauracian deposits, proved by the ammonites.
The ammonite fauna of Rauracian at Bałtów makes the first find in the eastern marginal area of the Holy Cross Mountains. Also the majority of the Brachiopoda and Lamellibranchia fauna of the Rauracian deposits in the eastern marginal area has been described for the first time there.
Summary
The author discusses stratigraphy of the Rauracian deposits occurring in the vicinity of Bałtów. Basing on the rich palaeontological data, the author confirms the accepted Rauracian age of coralliferous series and of subordinately spongeous organogenic deposits, which are present in the vicinity of Bałtów. On the basis of the ammonite fauna found in this area, the author tried to parallel the subdivision of Malm into Oxfordian, Rauracian, Astartian etc., applied in Poland, with the standard ammonite zones of the Upper Jurassic, by W. J. Arkell. This attempt gave the results concerning only the upper Oxfordian (Argovian) and Rauracian. Unfortunately, one could not uniformly determine the boundary between the Epipeltoceras bimammatum zone (Rauracian after the French and Polish authors) and the Streblites tenuilobatus zone (Astartian after the French and Polish authors). Simultaneously, the author states that the previously accepted boundary between the Rauracian and the Astartian, determined only on the lithological basis and supported by the ammonitic fauna, should be considerably removed upwards, because in this series, regarded up to now as being of Astartian age, the Oxfordian ammonite forms have been found there.
The author also pays attention to the necessity of revising the stratigraphical significance of the gastropod fauna of the Ptygmatis genus. This fauna regarded till present for an important stratigraphical element of the Astartian, appears at Bałtów in the Rauracian deposits, proved by the ammonites.
The ammonite fauna of Rauracian at Bałtów makes the first find in the eastern marginal area of the Holy Cross Mountains. Also the majority of the Brachiopoda and Lamellibranchia fauna of the Rauracian deposits in the eastern marginal area has been described for the first time there.