FORAMINIFEROS BENTONICOS DEL TALUD CONTINENTAL DESDE CONCEPCION A LAS ISLAS GUAITECAS (36º- 44° S), CHILE (FORAMINIFERA: . Article: FORAMINIFEROS BENTONICOS ROTALINIDOS DEL CENTRO SUR DE CHILE (36°S – 44°S). Add this to your Mendeley library Report an error. Abstract. PATARROYO-CAMARGO, Germán David and MARTINEZ-RODRIGUEZ , José Ignacio. DEEP SEA BENTHIC FORAMINIFERA OF THE PANAMA.
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Foraminíferos bentónicos actuales (Marginopora vertebralis… | Flickr
The succession of the species shows evolution of the size and morphological features of the test. Test elongate ovate, early stage quinqueloculine, later pseudotriloculine to biloculine, sutures depressed.
The lower part of the unit consists mostly of argillaceous and marly sandstone with inoceramids. Betonicos Pollution Bulletin, 60, The genus Pseudouvigerina has been considered a homeomorph of the modern Trifarina, which typically inhabits a region ranging from the outer shelf to upper continental slope. Abundant Palorbitolina lenticularis were observed. In addition, further planktic foraminifera recorded include Globotruncana area CushmanG. Some genera are highly tolerant to eutrophication e.
The foraminiferal assemblage recovered from the foarminiferos with inoceramids contains a great variety of benthic foraminifera; Pseudouvigerina, Bolivina, Loxostomun, Saracenaria, Lenticulina, Bolivinoides, Marginulina, Globorotalites, as well as nodosarids. Orbitolina lenticularis Blumenbach Douglass,p. The objective of this foraminiferros is to report and describe the occurrence of the larger benthic foraminifera recovered from the Acahuizotla Formation, in order to support an accurate dating of the interval studied; and to interpret the environment where this community flourished, examining the paleobiogeographical significance of the association.
Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy)
Infaunal foraminifera are dominated by Siphouvigerina proboscidea Schwager. High levels of trace metals cause the disappearance of ostracods and the exclusive presence of tolerant species of foraminifera, a response observed in other areas subjected to acid mine drainage processes and recent industrial pollution Ruiz et al.
The material consists of limestone samples that were collected from a m thick section Figure 2. The presence of Gansserina gansseri, as well as Rugoglobigerina hexacamerata, R. Both lagoons are subjected to different environmental impacts derived from public treatment stations, mining activities, agricultural residues or industrial wastes Figure 1. A review of Italian research over the last three decades: This paper tests the responses of these microorganisms to different environmental changes heavy metal pollution, treatment stations, artificial inlets, agricultural and urban sewages and compares them to those observed previously on ostracod assemblages.
A postrift phase occurred during the Kimeridgian, with the development of a carbonate platform Scott, ; Salvador, GEOS, 24 2p. The paleoenvironmental interpretation is based on the microfacies and fossil assemblage, which is composed of abundant Palorbitolina, Melathrokerion, Choffatella, Pseudocyclamminamiliolids and Lenticulina sp. Report of geological reconnaissance in Department of Tuxtla, Mezcalapa and Pichucalco: This impact was also noted on foraminiferal populations, forsminiferos they are foraminferos mainly by euryhaline, sometimes opportunistic species e.
The biostratigraphic significance of planktic foraminifera, considered to be an important tool for dating marine sedimentary sequences, has allowed us to assign an age to these samples.
This is based on the characters of the test and the morphology of the embryon of Palorbitolina lenticularis. This foraminiferal assemblage may correspond to biofacies 3 proposed by Olsson and Nyong Order Miliolida Lankester as Miliolidea, nom. The inoceramids reported in a recent study Alencaster and Omana, in press are, however, typical bentobicos early Maastrichtian age. The main effect of the Nador waste treatment station is the presence of low O2 dissolved contents 3.
March foraminiferow, Corrected manuscript received: Salinity is a major factor regulating ostracod community structure and the response of these crustaceans is the appearance bentonivos steno-haline species limited to freshwater to low brackish water ranges e.
A subsident basin, present during the Tithonian, was filled until the Neocomian. Most of the areas present water depths between 3 and 7 m, with an internal hydrodynamics dominated by the marine waters passing through the artificial inlet.
December 12, Manuscript accepted: Hariri for critical, helpful and constructive reviews of the manuscript. The environment was interpreted to be moderately deep water.
Environmental Research, Allomorphina cretacea Reuss, Bolivina incrassata Reuss, Bolivinoides draco Marsson, Cibicides foraminifero Sandidge, Clavulina trilatera Cushman, Dorothia oxycona Reuss, Gavelinella dayi White, Globorotalites conicus Carsey, Globorotalites spineus Cushman, Gyroidinoides cretacea Carsey, Gyroidina deppresa Alth, Lagena semiinterrupta Berry, Lenticulina muensteri Roemer, Loxostomum eleyi Cushman, Nonionella cretacea Cushman, Planulina texana Cushman, Praebulimina carseyae Plummer, Pseudonodosaria manifesto Reuss, Pseudouvigerina plummerae Cushman, Pullenia coryelli White, Saracenaria triangularis d’Orbigny, Siphonina prima Plummer Spiroplectammina laevis Roemer, Vaginulina plummerae Cushman, Salinity range is typical of marine waters Bilan d’automne 76 and d’hiver Genus Pseudocyclammina Yabe and Hanzawa, Pseudocyclammina sp.
Inoceramids, echinoids, and a few amonites were collected in this level. Test characterized by megalospheric embryonic apparatus in central position consisting of a large embryonic chamber covered by a layer of small chamberlets.
In addition, the age assignment agrees with Cherchi who stated that “shortly after its first occurrence in SW Europe late BarremianPalorbitolina lenticularis reached the American continent Flemish Cap, NW Atlantic.
Although the foraminifera are poorly preserved, some species were reported and illustrated by SEM photos for first time in this work Figures. Pantoja Alor et al. He gave it the name Acahuizotla Formation following Cserna The older forms of the first lineages do not have a horizontal plate. In addition, our data confirms the role of Nonion depressulum to bio-indicator of stressing conditions State University System of Florida, From the results of this study, four phylogenic lineages are proposed, based on species considered as important markers for this interval.