Abstract:
This paper reports the facies analysis and ichnology of a logged section in the lower part of the Mulichinco Formation (Early Valanginian), at Vega de Escalone in the Neuquén Basin, western Argentina. Four facies associations (A-D) have been defined, and they record deposition below the storm wave base (A), mainly as gravity-flow deposits (coquinas) devoid of any evidence of bioturbation. Hummocky cross stratification, wave and current ripples, and mud intervals record the offshore transition (B). Wave and current ripples and heterolithic stratification record the shoreface and a shallowing-upward trend (C). The uppermost part of the succession exhibits tidal influence (D). Trace fossils documented in the shoreface (C) include abundant Asteriacites lumbricalis, Lockeia isp., Gyrochorte comosa, Planolites isp., and fugichnial trace fossils that indicate a stressed environment affected by changes in sedimentation rate and probably salinity. In heterolithic ripple troughs, abundant Asteriacites lumbricalis are well preserved, protected by mud drapes, and they include evidence of horizontal displacement and vertical superposition. Lockeia and Planolites intersect Asteriacites, and Gyrochorte comosa is a faciescrossing trace fossil. Trace fossils in the tidally influenced interval (D) are restricted in diversity and distribution. Some bedding planes contain monospecific assemblages of Asteriacites lumbricalis; others contain J-shape burrows and Gyrochorte comosa. Trace fossils can be assigned to the Cruziana ichnofacies while vertical burrows in hummocky cross stratification are interpreted as records of the Skolithos ichnofacies. This apparent inversion in the trace-fossil distribution according to the marine ichnofacies can be a response to the change from an opportunistic to a background fauna. Copyright © 2007 SEPM (Society for Sedimentary Geology).
Referencias:
- Aguirre-Urreta, M.B., Neocomian ammonite biostratigraphy of the Andean basins of Argentina and Chile (1993) Revista Española de Paleontología, 8, pp. 57-74
- Aguirre-Urreta, M.B., Rawson, P.F., The ammonite sequence in the Agrio Formation (Lower Cretaceous), Neuquén Basin, Argentina (1997) Geological Magazine, 134, pp. 449-458
- Aguirre-Urreta, M.B., Pazos, P.J., Varela, R., Asteriacites lumbricalis von Schlotheim 1820: Ophiuroid trace fossil from the Mulichinco Formation, Valanginian of the Neuquén basin of western Argentina (abstract) (2004) First International Congress on Ichnology, p. 13. , April 2004, Trelew, Abstract Book
- Aguirre-Urreta, M.B., Rawson, P.F., Concheyro, G.A., Bown, P.R., Ottone, E.G., Lower cretaceous biostratigraphy of the neuquén basin (2005) The Neuquén Basin: A Case Study in Sequence Stratigraphy and Basin Dynamics, 252, pp. 57-81. , Veiga, G.D., Spalletti, L.A., Howell, J.A., and Schwarz, E., eds.: Geological Society of London, Special Publication
- Bell, C.M., Asteroid and ophiuroid trace fossils from the Lower Cretaceous of Chile (2004) Palaeontology, 47, pp. 51-66
- Bodenbender, G., Sobre el terreno jurásico y cretácico en los Andes argentinos entre el río Diamante y el río Limay (1892) Argentina Academia Nacional de Ciencias, Boletín, 13, pp. 5-44
- Buatois, L.A., Mángano, M.G., Aceñaloza, F.G., (2002) Trazas Fósiles. Señales de Comportamiento en El Registro Estratigráfico, p. 382. , Trelew, Edición Especial MEF No 2
- Frey, R.W., Howard, J.D., Prior, W.A., Ophiomorpha: Its morphologic, taxonomic, and environmental significance (1978) Palaeogeography, Palaeoclimatology, Palaeoecology, 23, pp. 199-223
- Fürsich, F.T., Shell concentrations (1995) Eclogae Geologicae Helvetiae, 88, pp. 643-655
- Fürsich, F.T., Oschmann, W., Shell beds as tools in basin analysis: The Jurassic of Kachchh, western India (1993) Geological Society of London, Journal, 150, pp. 169-185
- Gibert, J.M., Benner, J.C., The trace fossil Gyrochorte: Ethology and paleoecology (2002) Revista Española de Paleontología, 17, pp. 1-12
- Groeber, P., Observaciones geológicas a lo largo del meridiano 70. I. Hoja Chos Malal (1946) Sociedad Geológica Argentina, Revista, 1, pp. 177-208
- Groeber, P., Mesozóico, in geografía de la República Argentina (1953) Buenos Aires, Sociedad Argentina de Estudios Geográficos GAEA, 2, pp. 1-541
- Gulisano, C.A., Gutierrez Pleimling, A., Digregorio, R.E., Análisis estratigráfico del intervalo Tithoniano- Valanginiano (Formaciones Vaca Muerta, Quintuco y Mulichinco) en el suroeste de la provincia del Neuquén (1984) IX Congreso Geológico Argentino, Bariloche, Actas, 1, pp. 221-235
- Heinberg, C., The internal structure of the trace fossils Gyrochorte and Curvolithus (1973) Lethaia, 6, pp. 227-238
- Kidwell, S., Holland, S., Field description of coarse bioclastic fabrics (1991) Palaios, 6, pp. 426-434
- Kinne, O., Physiological aspects of animal life in estuaries with special reference to salinity (1966) Netherlands Journal of Sea Research, 3, pp. 222-244
- Lazo, D.G., (2004) Análisis de Concentraciones Fósiles Del Cretácico Inferior de Cuenca Neuquina, p. 338. , Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, unpublished Ph.D. thesis
- Legarreta, L., Gulisano, C., Análisis estratigráfico secuencial de la cuenca Neuquina (Triásico superior-Terciario inferior) (1989) Cuencas Sedimentarias Argentinas, 6, pp. 221-245. , Chebli, G., and Spalletti, L., eds.: Universidad Nacional de Tucumán, Serie Correlación Geológica, Facultad de Ciencias Naturales
- Legarreta, L., Kozlowski, E., Estratigrafía y sedimentología de la Formación Chachao, provincia de Mendoza (1981) VIII Congreso Geológico Argentino, 1, pp. 521-543. , San Luis, Actas
- Legarreta, L., Uliana, M.A., Jurassic-Cretaceous marine oscillations and geometry of back-arc basin fill, central Argentine Andes (1991) Sea Level Changes at Active Plate Margins, 12, pp. 429-450. , MacDonald, D.I.M., ed.: Processes and Product: International Association of Sedimentologists, Special Publication
- Legarreta, L., Uliana, M.A., El Jurásico y cretácico de la cordillera principal y la cuenca neuquina. Facies sedimentarias (1999) Geología Argentina, 29, pp. 339-416. , Caminos, R. ed.: Buenos Aires, Servicio Nacional Minero Geológico, Anales
- Mángano, M.G., Buatois, L.A., West, R.R., Maples, C.G., The origin and paleoecologic significance of the trace fossil Asteriacites in the Pennsylvanian of Kansas and Missouri (1999) Lethaia, 32, pp. 17-30
- Mángano, M.G., Buatois, L.A., West, R.R., Maples, C.G., Ichnology of a pennsylvanian equatorial tidal flat. The stull shale member at waverly, eastern Kansas (2002) Kansas Geological Survey, Bulletin, 245, pp. 1-130
- McIlroy, D., (2004) Ichnological Expressions of Key Stratigraphic Surfaces in An Aggrading Tide-dominated Deltaic Succession: Lajas Formation, Neuquén Basin, Argentina (Abstract), p. 55. , First International Congress on Ichnology, April 2004, Trelew, Abstract Book
- Mikulá, R., The ophiuroid taeniaster as a tracemaker of asteriacites, ordovician of czechoslovakia (1990) Ichnos, 1, pp. 133-137
- Myrow, P.M., Bypass-zone tempestite facies model and proximality trends for an ancient muddy shoreline and shelf (1992) Journal of Sedimentary Petrology, 62, pp. 99-115
- Myrow, P.M., Southard, J.B., Tempestite deposition (1996) Journal of Sedimentary Research, 66, pp. 875-887
- Pearse, J.S., Coelomic water volume control in the Antarctic sea star Odontaster validus (1967) Nature, 216, pp. 1118-1119
- Pemberton, S.G., Wightman, D.M., Ichnological characteristics of brackish water deposits (1992) Applications of Ichnology to Petroleum Exploration: A Core Workshop, 17, pp. 141-167. , Pemberton, S.G., ed.: SEPM, Core Workshop
- Pemberton, S.G., Maceachern, J.A., Frey, R.W., Trace fossil facies models: Environmental and stratigraphic significance (1992) Facies Models: Response to Sea-Level Change: Geological Association of Canada, pp. 47-72. , Walker, R.G., and James, N.P., eds
- Pruss, S.B., Bottjer, D.J., Early Triassic trace fossils of the western United States and their implications for prolonged environmental stress from the end-Permian mass extinction (2004) Palaios, 19, pp. 551-564
- Schwarz, E., Facies sedimentarias y modelo deposicional de la Formación Mulichinco (Valanginiano), Cuenca Neuquina Septentrional (1999) Asociación Argentina de Sedimentología, Revista, 6, pp. 37-59
- Segerstrale, S.G., Baltic sea (1957) Treatise on Marine Ecology and Paleoecology, 1, pp. 751-800. , Hedgpeth, J.W., ed., Ecology: Geological Society of America, Memoir
- Seilacher, A., Studien zur palichnologie II. Die fossilen ruhespuren (Cubichnia) (1953) Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen, 98, pp. 87-124
- Sequeira Fernandes, A.C., Borghi, L., Souza Carvalho, I., De Abreu, C.J., Guia dos Icnofósseis de invertebrados do Brasil (2002) Editora Interciencia, p. 255
- Spalletti, L.A., Gasparini, Z., Veiga, G., Schwarz, E., Fernandez, M., Mateos, S., Facies anóxicas, procesos deposicionales y herpetofauna de la rampa marina tithoniano-berriasiano en la cuenca neuquina (Yesera del Tromen), Neuquén, Argentina (1999) Revista Geológica de Chile, 26, pp. 109-123
- Ten Hove, H.A., Van Der Hurk, P., A review of recent and fossil serpulid "reefs"; Actuopalaeontology and the "Upper Malm" serpulid limestones in NW Germany (1993) Geologie en Mijnbouw, 72, pp. 23-67
- Uliana, M.A., Legarreta, L., Laffitte, G.A., Villar, H., Estratigrafía y geoquímica de las facies generadoras de hidrocarburos en las cuencas petrolíferas de Argentina (1999) IV° Congreso de Exploración y Desarrollo de Hidrocarburos (Mar Del Plata), 2, pp. 1-62. , Buenos Aires
- Von Schlotheim, E.F., (1820) Die Petrefactenkunde Auf Ihrem Jetzigen Standpunkte Durch Die Beschreibung Seiner Sammlung Versteinerter und Fossiler Überreste des Thier- Und Pflanzenreiches der Vorwelt Erläutert, p. 437. , Gotha, Becker
- Weaver, C., (1931) Paleontology of the Jurassic and Cretaceous of West Central Argentina, 1, p. 469. , University of Washington, Memoirs
- Wightman, D., Pemberton, S., Singh, C., Depositional modelling of the upper mannville (Upper Cretaceous) central Alberta, implications for the recognition to brackish water deposits (1987) Reservoir Sedimentology, 40, pp. 189-220. , Tillman, R., and Weber, K., eds.: SEPM, Special Publication
- Windhausen, A., Líneas generales de la estratigrafía del Neocomiano en la Cordillera Argentina (1918) Argentina Academia Nacional de Ciencias, Boletín, 23, pp. 97-128
- Wilson, M.A., Rigby, J.K., Asteriacites lumbricalis von Schlotheim 1820: Ophiuroid trace fossils from the Lower Triassic Thaynes Formation, central Utah (2000) Ichnos, 7, pp. 4-49
Citas:
---------- APA ----------
Rodríguez, D.L., Pazos, P.J., Aguirre-Urreta, M.B., Bromley R.G., Buatois L.A., Mangano G., Genise J.F.,..., Melchor R.N.
(2007)
. Cretaceous ophiuroid trace fossils from the Neuquén basin, Argentina. SEPM Special Publications, 88, 97-105.
http://dx.doi.org/10.2110/pec.07.88.0097---------- CHICAGO ----------
Rodríguez, D.L., Pazos, P.J., Aguirre-Urreta, M.B., Bromley R.G., Buatois L.A., Mangano G., et al.
"Cretaceous ophiuroid trace fossils from the Neuquén basin, Argentina"
. SEPM Special Publications 88
(2007) : 97-105.
http://dx.doi.org/10.2110/pec.07.88.0097---------- MLA ----------
Rodríguez, D.L., Pazos, P.J., Aguirre-Urreta, M.B., Bromley R.G., Buatois L.A., Mangano G., et al.
"Cretaceous ophiuroid trace fossils from the Neuquén basin, Argentina"
. SEPM Special Publications, vol. 88, 2007, pp. 97-105.
http://dx.doi.org/10.2110/pec.07.88.0097---------- VANCOUVER ----------
Rodríguez, D.L., Pazos, P.J., Aguirre-Urreta, M.B., Bromley R.G., Buatois L.A., Mangano G., et al. Cretaceous ophiuroid trace fossils from the Neuquén basin, Argentina. SEMP Spec. Publ. 2007;88:97-105.
http://dx.doi.org/10.2110/pec.07.88.0097