Algues, Pseudo-algues et Foraminifères des niveaux bachkiriens dans les secteurs d'escarra et aragon subordan (pyrénées aragonaises, espagne)

Vachard, Daniel; Perret, Marie-France; Delvolvé, Jean-Jacques

doi:10.1016/s0016-6995(89)80068-3

Cited by 22 publications

(11 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the other hand, the illustrations of Homann (1972), first revised by Vachard et al (1989), can be re-interpreted as follows: The fig. 24 is a small Mizzia sp., fig.…”

Section: Stratum Typicum -Tarusian (Earliest Serpukhovian)mentioning

confidence: 99%

Late Viséan-early Serpukhovian cyanobacteria and algae from the Montagne Noire (France); taxonomy and biostratigraphy

Vachard¹,

Cózar²,

Aretz³

et al. 2016

Bull. Geosci.

View full text Add to dashboard Cite

“…On the other hand, the illustrations of Homann (1972), first revised by Vachard et al (1989), can be re-interpreted as follows: The fig. 24 is a small Mizzia sp., fig.…”

Section: Stratum Typicum -Tarusian (Earliest Serpukhovian)mentioning

confidence: 99%

Late Viséan-early Serpukhovian cyanobacteria and algae from the Montagne Noire (France); taxonomy and biostratigraphy

Vachard¹,

Cózar²,

Aretz³

et al. 2016

Bull. Geosci.

View full text Add to dashboard Cite

“…These two species are not differentiated in this paper because of recrystallization in many cases and the systematic controversy (cf. Roux, 1985;Vachard et al, 1989;Mamet, 1991). Donezella has been assigned to different groups: red algae (Maslov, referred in Rácz, 1964), possibly green algae (Pia, 1937;Johnson, 1963), codiacean (Rácz, 1964), sponges (Termier et al, 1977), algae incertae (Rich, 1967), foraminifera (Riding and Jansa, 1974;cf.…”

Section: Mound Paleontology and Paleoecologymentioning

confidence: 99%

Internal structure and depositional environment of Late Carboniferous mounds from the San Emiliano Formation, Cármenes Syncline, Cantabrian Mountains, Northern Spain

Samankassou

2001

Sedimentary Geology

View full text Add to dashboard Cite

Well-exposed mounds are common in limestone of the Late Carboniferous San Emiliano Formation, Cantabrian Mountains (Northern Spain). They occur as obvious primary topographic features. Careful study of the mound intervals and surrounding strata revealed the internal structures of mounds and the factors controlling their growth. The substrate (2 -3 m) of the mounds consists of greyish to reddish, bedded oolitic and oncolithic packstone and grainstone. Crinoids, fragments of the alga Epimastopora, and, rarely, bryozoans are present. Ooids and oncoids indicate a wave-dominated high-energy environment. Presence of quartz indicates the influence of terrigenous siliciclastic input. Mound intervals (6 -12 m thick) are characterized by skeletal -microbial boundstone. Donezellid algae, agglutinated worm tubes, and calcisponges are the dominant fossils. Smaller foraminifers, gastropods, and brachiopods are also present. A peloidal-clotted matrix is characteristic and accounts for more than 30% of the mound volume. Intraframe pores are mainly filled by peloidal sediment and early marine cement. Intermound strata are approximately one-third as thick as time equivalent mounds. Mound fossils (algae, agglutinated worm tubes, and sponges) are uncommon. However, intermound strata are generally more diverse than the mounds, containing fusulinids, smaller foraminifers, bryozoans, gastropods, crinoids, and bioclasts. Some of these fossils have micritic envelopes. Bedded packstone and grainstone, 3 -6 m thick, with siliciclastic debris, rugose corals, and chaetetid sponges characterize the capping facies. Coated grains and small ooids are uncommon. This facies indicates shallowing to a higher energy environment and/or a higher input of siliciclastics, inhibiting mound growth. Mounds are interpreted to have accreted in a quiet environment below wave base. This position is comparable to the depositional environment inferred for many Late Paleozoic mounds described elsewhere, e.g., from Texas and New Mexico, Canadian Archipelago, and Carnic Alps in Austria. Mound relief is explained by (1) accumulation of peloidal-clotted sediments limited to boundstone and probably related to microbial activities, (2) widespread marine cementation within this area, and (3) low export of mound fossils to intermound areas. The position of the mounds within the sequence, and their initiation, size and termination, seem to be mainly controlled by sea-level fluctuations and siliciclastic input. D

show abstract

“…Where Donezella is found in situ (as either a shrub like growth or as an encrusting sheet) it is always the dominant biota with very few other biotas found in association. Maslov (1929) originally assigned Donezella to the red algae (Johnson 1963), however, in successive subsequent studies Donezella has been considered to be: green (Codiaceae) alga (Rácz 1964), alga incertae sedis (Rich 1967), Foraminifera (Riding 1979), calcareous sponges (Termier et al 1977), microproblematica (Riding 1979;Chuvashov and Riding 1984), green (Paleosiphonocladales) algae (Shuysky 1985;Ivanova 1999), green algae of incertae familiae (Groves, 1986), green (Dasycladales) algae (Deloffre, 1988) and pseudo-algae (Vachard et al 1989). Recent work regarding Donezella refers to the genus as green (Chlorophycophyta) algae (Mamet and Villa 2004), algae incertae sedis (Mamet and Zhu 2005), algospongia (Vachard and Cózar 2010) or more commonly, microproblematica (Samankassou 2001;Della Porta et al 2002;Choh and Kirkland 2006;Corrochano et al 2012).…”

Section: Palaeoecology Of the Moundsmentioning

confidence: 99%

A novel population of composite mounds: their initiation, growth and demise. San Emiliano Formation, Cantabrian Mountains, Spain

Rogers

2018

J Iber Geol

View full text Add to dashboard Cite

Purpose Mounds from the Pennsylvanian aged San Emiliano Formation (Cantabrian Mountains, Spain) are commonly well exposed. These mounds range from 2 to 50 m in height and are observed to be primary geological features. The mounds are described and classified and the factors and controls of mound nucleation, growth and demise have been established. Methods Microfacies analysis of 177 thin sections has revealed the composition of the mounds and surrounding carbonates. Results Composite mounds, exhibiting characteristic components of both Cluster mounds and Agglutinated Microbial mounds are described. The mounds are skeletal-microbial/pack-wackestones. Peloidal, homogenous and clotted micrites are the main sedimentological constituents of the mounds. Microfossils are dominant with Donezella, Claracrusta, Rothpletzella and Girvanella being common. Small foraminifera, bryozoans, corals and algae are all present within the mounds, but are more common within off-mound carbonates. Conclusions The formation of the mounds was controlled by a dynamic relationship between Donezellacean algae, and microscopic encrusters, a bio-mechanism not observed in mud mounds elsewhere. Fluctuating environmental conditions lead to the alternate dominance between the two groups, resulting in accretion and stabilisation of carbonate muds. These mounds are compositionally different to their Pennsylvanian counterparts.Keywords Composite mound · Agglutinated microbial mound · Cluster mound · Donezella · Encrusting biota · Microfacies analysis · Pennsylvanian Resumen Propósito Los montículos de la Formación San Emiliano de edad Pensilvaniense (Cantabrian Mountains, España) están comúnmente bien bexpuestos. Estos montículos tienen una altura de 2 a 50 m y se observa que son rasgos geológicos primarios. El los montículos se describen y clasifican y los factores y controles de la nucleación, el crecimiento y la fallecimiento tienen que ver con los siguientes factores se ha establecido. Métodos El análisis de microfacias de 177 sección delgada ha revelado la composición de los montículos y carbonatos circundantes. Resultados Montículos compuestos, que exhiben los componentes característicos de ambos montículos Cluster y Microbial aglutinado. Se describen los montículos. Los montículos son esqueléticos-microbianos lodogranular/lodosa. Peloide, homogéneo y coagulado micrites son los principales componentes sedimentológicos de los montículos. Los microfósiles dominan con Donezella, Claracrusta, Rothpletzella y Girvanella son comunes. Pequeños foraminíferos, briozoarios, corales y algas son todos ellos presente dentro de los montículos, pero son más comunes dentro de los carbonatos fuera del montículos. Conclusiones La formación de los montículos estaba controlada por una relación dinámica entre las algas donezellaceanas, y incrustaciones microscópicas, un mecanismo biológico no observado en montículos de lodo en otras partes. Medio ambiente fluctuante condiciones conducen a la dominación alternada entre los dos grupos, resultando en la creaci...

show abstract

Algues, Pseudo-algues et Foraminifères des niveaux bachkiriens dans les secteurs d'escarra et aragon subordan (pyrénées aragonaises, espagne)

Cited by 22 publications

References 17 publications

Late Viséan-early Serpukhovian cyanobacteria and algae from the Montagne Noire (France); taxonomy and biostratigraphy

Late Viséan-early Serpukhovian cyanobacteria and algae from the Montagne Noire (France); taxonomy and biostratigraphy

Internal structure and depositional environment of Late Carboniferous mounds from the San Emiliano Formation, Cármenes Syncline, Cantabrian Mountains, Northern Spain

A novel population of composite mounds: their initiation, growth and demise. San Emiliano Formation, Cantabrian Mountains, Spain

Contact Info

Product

Resources

About