Les Marnes à Foraminifères et les Schistes à Poissons de Bremmelbach (Bas-Rhin). Etudes sédimentologiques et micropaléontologiques. Reconstitution du milieu au début du Rupélien dans le fossé rhénan

Doebl, Franz; Müller, Carla; Schuler, Monique; Sittler, Claude; Weiler, Helmut

doi:10.3406/sgeol.1976.1499

Cited by 7 publications

(3 citation statements)

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“…The finely laminated sediments contain almost monospecific and nicely preserved coccoliths and coccospheres, which show taxonomic changes from one light lamina to the next one. Similar findings were also documented for other Oligocene deposits in France (Doebl et al, 1976;Noel et al, 1993a). All the assemblages are characterized by excellent preservation and are dominated by very few taxa, which seem to be represented by small coccoliths.…”

Section: Previous Records Of Calcareous Nannofloras From Lagoonal Envsupporting

confidence: 75%

Campanian Dwarf Calcareous Nannofossils from Wodejebato Guyot

Erba¹,

Watkins²,

Mutterlose³

1995

Proceedings of the Ocean Drilling Program, 144 Scientific Results

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Calcareous nannofossils occur in lagoonal sediments recovered from Sites 873, 874, and 877 drilled on Wodejebato Guyot in the central Pacific Ocean. Nannofloras are present only in a few layers, from which several smear slides were prepared. All the specimens were counted, and the relative abundance of taxa was computed as percentages. Assemblages are characterized by excellent preservation, very high diversity (= number of taxa), but extremely low abundance. Both diversity and abundance decrease from the inner perimeter ridge along the northern edge of the atoll (Sites 877 and 874) to the inner lagoon (Site 873), but the assemblage composition is very similar at the three sites. The dominant species are Prediscosphaera spp., Cribrosphaerella ehrenbergii, Cretarhabdus spp., Biscutum constans, and Zygodiscus erectus. Watznaueria barnesae is common but not dominant. Holococcoliths were observed at all sites. All taxa are represented by dwarf specimens.At Site 877, the CC22 Zone of late Campanian age was determined; at Sites 873 and 874, nannofloral assemblages indicate a Campanian age. The Cenomanian-restricted species Corollithion kennedyi was found at Site 877, suggesting the presence of older sediments on Wodejebato Guyot. Evidence of reworking is also given by the occurrence of recrystallized, broken, and often phosphatized specimens of long-ranging taxa. Reworking is more abundant in the lagoon than at the inner ridge.The investigation was extended to the upper Campanian interval recovered at Site 869, which was drilled during Leg 143 on the oceanic floor south of Wodejebato Guyot. Here, nannofloras are represented by normal-sized specimens, and the assemblage composition is typically oceanic, suggesting that the nannoplankton at Sites 873,874, and 877 adjusted to restricted environmental conditions. Calcareous nannoplankton occur in extant lagoons, where coccoliths are found in the sediments and in the water samples. Lagoonal nannofloras are also preserved in the fossil record of various ages: Neogene, Oligocene, Paleocene, Early Cretaceous, and Middle to Late Jurassic. There are similarities and differences between the nannofloras from Wodejebato and assemblages from other ancient lagoons. The small size of the coccoliths seems to be a peculiarity of lagoonal assemblages and may be related to the unusual environmental conditions. The genus Braarudosphaera-inferred to be a low salinity form-is usually absent.The relatively high abundance of fertility indicators B. constans and Z. erectus at Sites 873, 874, and 877 is possibly controlled by the proximity of Wodejebato Guyot to the paleoequatorial upwelling belt during the Campanian. In fact, similar nannofloras were previously reported from mid-Cretaceous sites at comparable paleolatitudes in the central-western Pacific. This interpretation is substantiated by the record of Site 869, where a few layers are relatively enriched in Prediscosphaera spp., C. ehrenbergii, B. constans, and Z erectus, although nannofloral assemblages for the most part are aff...

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Section: Previous Records Of Calcareous Nannofloras From Lagoonal Envsupporting

confidence: 75%

Campanian Dwarf Calcareous Nannofossils from Wodejebato Guyot

Erba¹,

Watkins²,

Mutterlose³

1995

Proceedings of the Ocean Drilling Program, 144 Scientific Results

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“…The Série Grise (Figs. 3, 4 and 7) is a typical marine unit (Sittler, 1965(Sittler, , 1969aDoebl et al, 1976;Berger et al, 2005a, b;Roussé, 2006;Pirkenseer, 2007;Le Metayer et al, 2008;De Pietri et al, 2010;Roussé et al, 2012). The stratigraphic attribution (Fig.…”

Section: Oligocene 431 the Série Grisementioning

confidence: 99%

“…Practically, the best criterion is the occurrence of abundant large-sized foraminifera and the disappearance of the millimetric chalk laminae characterizing the Schistes à Poissons. Up to 144 species of foraminifera have been described in the Marnes à Foraminifères, including some giant species such as Cyclammina placenta (Doebl et al, 1976) that are visible easily to the naked eye. The GR signals in both formations, Schistes à Poissons and Marnes à Foraminifères (Fig.…”

Section: Marnes à Foraminifèresmentioning

confidence: 99%

The complete lithostratigraphic section of the geothermal wells in Rittershoffen (Upper Rhine Graben, eastern France): a key for future geothermal wells

Duringer

Aichholzer

Orciani³

et al. 2019

BSGF - Earth Sci. Bull.

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Between 2012 and 2014, in Rittershoffen, in the Upper Rhine Graben, two geothermal boreholes (GRT-1 and GRT-2) reached the granitic basement at a depth of around 2150 m. The wells crossed about 1160 m of Cenozoic and 1050 m of Mesozoic. In the Cenozoic, these wells crossed the greatest part of the Eocene, the lower part of the Oligocene and a thinner Pliocene. The Quaternary is poorly represented (less than 10 m). In the Mesozoic, the wells crossed the Lower Dogger, the entire Lias and the entire Triassic. A reduced thickness of about 50 m of Upper Permian terminates the sedimentary column before entering into the granitic basement. A major erosional unconformity separates the Middle Jurassic from the Tertiary units (the Upper Jurassic, entire Cretaceous and Paleocene are absent). The Rittershoffen drilled doublets were the subject of particular attention concerning the acquisition of a very precise stratigraphic profile. In this paper, we give the recognition criteria for the fifty-seven formations crossed by the GRT-1 well and their upper and lower boundaries as well as their specific gamma ray signatures. The data are presented in four figures: a general complete log displaying the main sets and three detailed, precise logs showing the sedimentary formations overhanging the granitic basement: the Tertiary, the Jurassic, the Triassic, the Permian and the basement.

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