In: Geologica Carpathica, 2019, vol. 70, no. 4, p. 325–354
A cyclostratigraphic interpretation of peritidal to shallow-marine ramp deposits of the early Middle Triassic (Anisian) Opletnya Member exposed in outcrops along the Iskar River gorge, NW Bulgaria, is presented. Based on facies trends and bounding surfaces, depositional sequences of several orders can be identified. New biostratigraphic data provide a time frame of the studied succession with...
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In: Stratigraphy & Timescales, 2018, vol. 3, p. 151–187
The sedimentary record of ancient shallow-marine carbonate platforms commonly displays a stacking of different facies, which reflects repetitive changes of depositional environments through time. These changes can be induced by external factors such as cyclical changes in climate and/or sea level, but also by internal factors such as lateral migration of sediment bodies and/or changes in the...
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In: Archives des Sciences, 2018, vol. 70, p. 205-282
Le terme de Formation du Grand Essert a été proposé en 2016 pour remplacer ceux de « Marnes d’Hauterive » auct. et « Pierre jaune de Neuchâtel » auct. attribués à l’« Hauterivien » auct. dans le Jura franco-suisse. L’objet de cette note est, dans un premier temps, de décrire et d’interpréter la lithologie de la coupe-type représentative de cette nouvelle formation,...
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In: Geologica Carpathica, 2018, vol. 69, no. 2, p. 129–148
Sedimentary facies and cycles of the Triassic continental–marine transition of NW Bulgaria are documented in detail from reference sections along the Iskar river gorge between the villages of Tserovo and Opletnya. The depositional environments evolved from anastomosing and meandering river systems in the Petrohan Terrigenous Group to mixed fluvial and tidal settings in the Svidol Formation,...
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In: Swiss Journal of Geosciences, 2016, vol. 109, no. 2, p. 201–220
In the course of the HARMOS project of the Swiss Geological Survey, the lithostratigraphic subdivisions of the Cretaceous sedimentary rocks outcropping in the Swiss Jura Mountains were revisited. New formation names are proposed where only inadequate facies terms existed so far. As in some cases outcrop conditions in the Swiss Jura do not allow for logging complete sections to characterise...
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In: Facies, 2013, vol. 58, no. 1, p. 287-297
The dasycladale Clypeina helvetica was described and illustrated with six drawings by Morellet and Morellet (Bull Soc Géol Fr 4o ser 18:102–105, 1918) from the “Bartonian” of the Helvetic Zone of southwestern Switzerland. Since then, C. helvetica has not been reported again neither from Switzerland nor from any other locality. Abundant material sampled from the Priabonian Diablerets Member...
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In: Swiss Journal of Geosciences, 2009, vol. 102, no. 2, p. 247–270
Based on a well-established bio- and sequence-stratigraphic framework, a narrow time window in the Bimammatum ammonite zone (Late Oxfordian) is investigated in six Swiss Jura sections representing a shallow-water carbonate platform. From the detailed facies and microfacies analysis of oncoid-rich (Hauptmumienbank Member) and ooid-rich (Steinebach Member) limestones, a microfacies...
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In: Swiss Journal of Geosciences, 2007, vol. 100, no. 3, p. 407-429
Detailed investigation of facies and sedimentary structures reveals that, during the Middle Oxfordian to Late Kimmeridgian, the shallow carbonate platform of the Swiss and French Jura Mountains recorded high-frequency sea-level fluctuations quite faithfully. The cyclostratigraphic analysis within the established biostratigraphic and sequence-chronostratigraphic framework implies that the...
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In: Facies, 2007, vol. 53, no. 4, p. 535-552
Abundant lagoonal oncoids occur in the Late Oxfordian Hauptmumienbank Member of the Swiss Jura Mountains. Four oncoid types are observed in the studied sections and classified according to the oncoid surface morphology, the structure and composition of the cortex, and the texture and fauna of the encasing sediment. Micrite-dominated oncoids (types 1 and 2) have a smooth surface. Type 1 has a...
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In: Terra Nova, 2005, vol. 17(5), p. 407
Climatic, oceanographic and ecological changes that control the formation and deposition of sediment in shallow and deep depositional environments commonly occur with periodicities of a few 10 000 years. Consequently, in order to interpret sedimentary sequences in the geological past, high time resolution is required. This is best obtained by cyclostratigraphy. Three sections have been studied in...
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