Full Text | Download - Grzybowski Foundation - The ...

More documents

Recommendations

Info

Alegret, Ortiz & Kaminski (eds.), 2012. Ninth International Workshop on Agglutinated Foraminifera, Abstract Volume References: Caramés, A. & Malumián, N. 2006. La Familia Rzehakinidae (Foraminifera) en el Cretácico Superior- Paleogeno de la cuenca Austral y la plataforma continental atlántica adyacente, Argentina. Ameghiniana, 43, 649-668. Loeblich, A.R. & Tappan, H. 1989. Implications of wall composition and structure in agglutinated foraminifera. Journal of Paleontology, 63, 769-777. Malumián, N. & Caramés, A. 2002. Foraminíferos de sedimentitas ricas en carbono orgánico: Formación La Barca, Paleoceno superior, Tierra del Fuego. República Argentina. Revista de la Asociación Geológica Argentina, 57, 219-231. Malumián, N. & Jannou, G. 2010. Los Andes Fueguinos: el registro micropaleontológico de los mayores acontecimientos paleooceanográficos australes del Campaniano al Mioceno. Andean Geology, 37, 346–375, Available at: http://www.scielo.cl/andeol.htm Malumián, N. & Náñez, C. 1990. Foraminíferos aglutinados del Cretácico Superior de cuenca Austral (Provincia de Santa Cruz). Argentina. Bioestratigrafía de Sistemas Regionales del Jurásico y Cretácico de América del Sur (W. Volkheimer, ed.), 497-551. Malumián, N. & Náñez, C. 2002. Los foraminíferos de la provincia de Santa Cruz: su significado geológico y paleoambiental. Geología y Recursos Naturales de Santa Cruz, Relatorio del XV Congreso Geológico Argentino (M.J. Haller, ed.), 481-493. Malumián, N. & Náñez, C. 2011. The Late Cretaceous–Cenozoic transgressions in Patagonia and the Fuegian Andes: foraminifera, palaeoecology, and palaeogeography. Biological Journal of the Linnean Society, 103, 269–288. Malumián, N., Náñez, C., Jannou, G. & Arenillas, I. 2012. A conspicuous agglutinated new genus of calcareous cemented and perforate wall with remaneicid test morphology from the early Eocene southern high latitudes. This volume (next page). Náñez, C. & Malumián, N. 2000. Foraminíferos aglutinados de la Formación Cerro Cazador. In Malumián et al., Hoja Geológica 5172 III Yacimiento Río Turbio, Provincia de Santa Cruz. Servicio Geológico Minero Argentino, Boletín 247, 69-78. Náñez, C. & Malumián, N. 2008. Paleobiogeografía y paleogeografía del Maastrichtiano marino de Patagonia, Tierra del Fuego y de la Plataforma Continental Argentina basada en foraminíferos bentónicos. Revista Española de Paleontología, 23, 273-300. Olivero, E.B., Malumián, N., Palamarczuk, S. & Scasso, R.A. 2002. El Cretácico superior-Paleogeno del área del Río Bueno, costa atlántica de la Isla Grande de Tierra del Fuego. Revista de la Asociación Geológica Argentina, 57, 199-218. Riccardi, A.C. 2002. Invertebrados del Cretácico Superior. Geología y Recursos Naturales de Santa Cruz, Relatorio del XV Congreso Geológico Argentino (M.J. Haller, ed.), 461-479. 53
Alegret, Ortiz & Kaminski (eds.), 2012. Ninth International Workshop on Agglutinated Foraminifera, Abstract Volume A conspicuous agglutinated new genus of calcareous cemented and perforate wall with remaneicid test morphology from the early Eocene southern high latitudes Norberto MALUMIÁN 1,2 , Carolina NÁÑEZ 1,2 , Gabriel JANNOU 2 and Ignacio ARENILLAS 3 1 Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina. 2 Servicio Geológico Minero Argentino, Benjamín Lavaisse 1194, (C1107BJD) Buenos Aires, Argentina 3 Dpto. Ciencias de la Tierra (Paleontología)-IUCA, Universidad de Zaragoza, 50009 Zaragoza, Spain e-mail: n.malumian@yahoo.com In southernmost South America, the Austral Basin contains a paradigmatic marine Paleogene sequence with representative assemblages of benthic foraminifera in an oceanic hemisphere. These assemblages include several calcareous taxa endemic to high southern latitudes (Malumián and Náñez 2011), such as the conspicuous genera Boltovskoyella and Antarcticella. The latter was originally assigned to a planktonic paleohabit, due to its misleading gross morphology. We add to these taxa of peculiar morphology, a new genus and new species with a wall test agglutinating small foreign particles with very abundant calcareous cement and subdivided chambers that previously led us to misinterpret it as a complex calcareous form (Malumián and Náñez 2002). This peculiar form was found in the early Eocene Punta Noguera Formation, in the Tierra del Fuego Island, from outcrops of very difficult access, so that the gathered material is limited. The new genus has a morphology and paleohabitat similar to those of the subfamily REMANEICINAE Loeblich and Tappan 1964, particularly to the genera Bruneica and Remaneica: It has a low trochospirally coiled small test; the first two or three chambers are globular and undivided; subsequent chambers are semilunate from spiral view, mushroomshaped from umbilical view, and subdivided by radial secondary septula; the interiomarginal aperture is situated at the end of a median umbilically directed scarcely perforate projection resembling to that of Bruneica. The new genus differs from the organically-cemented REMANEICINAE by the perforate rigid wall, completely calcareous in the initial chambers to very finely agglutinate in the last whorl. It bears scattered perforations, larger on the umbilical side (diameter: 3.75 - 5 µm) and smaller on the spiral side (2.5 - 3.35 µm), mostly situated in the last whorl where the agglutinated foreign particles are more evident. Other smaller perforations are preserved as thin and long gypsum infillings (diameter: 2,5 µm) in the initial chambers of a deeply etched test. Two types of tests are recognized in the general shape: one is the more common watchglass-shaped form that apparently reaches larger sizes (microspheric form?), and the other corresponds to more conical forms with a prominent umbo on the spiral side (megalospheric form?). The paleohabit of this new genus, according to its Holocene homeomorphous Bruneica and Remaneica, would be attached and inhabiting tropical shallow water. This interpretation is also supported by the associated foraminifera, the benthics dominated by attached morphotypes, and the scarce planktonic foraminifera, only represented by small serial forms (Malumián et al., 2009, Malumián and Jannou, 2010). Another close homeomorph genus is Abyssotherma, described from the vicinity of deep-sea hydrothermal springs, a contrasting bathymetric but thermally similar paleoenvironment (Brönnimann et al., 1989). 54
Page 2 and 3:
Ninth International Workshop on Agg
Page 4 and 5:
Ninth International Workshop On Agg
Page 6:
Alegret, Ortiz & Kaminski (eds.), 2
Page 9 and 10: Alegret, Ortiz & Kaminski (eds.), 2
Page 59: Alegret, Ortiz & Kaminski (eds.), 2
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
Page 121:
show all

Full Text | Download - Grzybowski Foundation - The ...

Create successful ePaper yourself

Delete template?

Save as template?