DOCSLIB.ORG

Nuevas Evidencias De Ammonites Jurásicos Del Género Coroniceras En La Parte Norte De Los Andes Centrales: Implicancias Cronoestratigráficas

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Nuevas Evidencias De Ammonites Jurásicos Del Género Coroniceras En La Parte Norte De Los Andes Centrales: Implicancias Cronoestratigráficas Boletín de la Sociedad Geológica del Perú, v. 108, p. 213-218 (2013) 213 ____________________________________________________________________________________________________________________ Boletín de la Sociedad Geológica del Perú journal homepage: www.sgp.org.pe ISSN 0079-1091 ____________________________________________________________________________________________________________________ Nuevas evidencias de ammonites jurásicos del género Coroniceras en la parte norte de los Andes Centrales: Implicancias cronoestratigráficas Jarold Arévalo1, César Chacaltana1, Aldo Alván1,2, y Waldir Valdivia1 1 INGEMMET, Av. Canadá 1470, San Borja, Lima ([email protected]) 2 Geowissenschaftliches Zentrum Göttingen, Abt. Sedimentologie und Umweltgeologie, Goldschmidtstraße 3, 37077 Göttingen, Alemania ([email protected]) ____________________________________________________________________________________________________________________ 1. Introducción estudios en bioestratigrafía de ammonites fueron los realizados por Tilmann (1917), Jaworski (1922), Geyer En afloramientos de la carretera Belaunde Terry, entre las (1979), Prinz (1985), y Hillebrandt (1994), y mediante el ciudades de Pedro Ruiz y Yambrasbamba, departamento presente trabajo se documenta por primera vez la de Amazonas (Fig. 1), se han podido identificar secuencias existencia de niveles marinos del Sinemuriano inferior. La estratigráficas superiores de la Formación Aramachay presente contribución pone en evidencia nuevos registros (Grupo Pucará) con fauna de ammonites. Estas secuencias, de ammonites del género Coroniceras HYATT, 1867: producto del establecimiento del sistema de rift durante el Coroniceras brevidorsale, Coroniceras rotiforme y intervalo Triásico superior–Jurásico inferior (Mégard, Coroniceras reynesi, los cuales permiten reconocer las 1968; Palacios, 1980; Rosas et al., 2007), han librado una zonas de Arietites bucklandi y Arnioceras semicostatum y fauna nerítica importante, cuya distribución ha permitido precisar la cronoestratigrafía del Jurásico inferior en el precisar la geocronología en el sector. Los primeros borde noreste de los Andes Centrales. Figura 1. Ubicación de la zona de estudio en la Cordillera Oriental del Norte peruano. 214 Boletín de la Sociedad Geológica del Perú, v. 108, p. 213-218 (2013) 2. Paleontología sistemática Coroniceras (Primarietites) reynesi (SPATH) (Lámina 1, Fotos 8, 9) Phyllum Mollusca Clase Cephalopoda Material: Código INGEMMET-6160/2. Un molde de Subclase Ammonoidea ZITTEL, 1884 ammonite en estado de conservación regular. Descripción: La concha es evoluta, presenta costillaje Orden Ammonitida AGASSIZ, 1847 fino y muy numeroso, con ligera concavidad. En la última Suborden Ammonitina HYATT, 1889 espira cerca de la abertura se observa que las costillas Superfamilia Psilocerataceae HYATT, 1867 tienden a ser muy curvadas hacia adelante, hasta llegar a Familia Arietitidae HYATT, 1874 la parte ventral de la concha. Bioestratigrafía: Parte inferior de la zona de Arnioceras Género Coroniceras HYATT, 1867 semicostatum (Quinzio, 1987). Especie tipo Ammonitekridion ZIETEN, 1830 (= Geocronología: Sinemuriano inferior, parte superior Arnioceratoides SPATH, 1922) (192.6 ± 1.5 Ma). Coroniceras brevidorsale (QUENSTEDT) (Lámina 1, Fotos 6, 7) 3. Implicancias cronoestratigráficas Material: Código INGEMMET-6160. Un molde de ammonite en estado de conservación regular. Desde el Triásico superior hasta el Cretácico medio se Descripción: La concha es evoluta, presenta costillaje registra una gran extensión tectónica de rift (Alemán & fino, recto y sub-cuadrado. En la última espira cerca de la Ramos, 2000; Jaillard et al., 2000; Sempere et al., 2002; abertura se observa que las costillas tienden a ser Rosas et al., 2007), donde el espacio de acomodación inclinadas hacia delante (abertura). La quilla es ancha y sedimentario estuvo probablemente restringido hasta el presenta una ligera tendencia a bullae. Jurásico medio por el alto estuctural Totos-Paras en Bioestratigrafía: Parte superior de la zona de Arietites Ayacucho (Carlotto et al., 2009), como posible bucklandi (Quinzio, 1987). consecuencia de los movimientos transtensionales que Geocronología: Sinemuriano inferior, parte superior actuaron entre las cuencas Arequipa y Pucará (Jacay et al., (192.6 ± 1.5 Ma). 2002; Acosta et al., 2010). Los ammonites colectados se comparan con los reportados en cuencas europeas contemporáneas por estar estrechamente vinculados con Coroniceras (Coroniceras) rotiforme (SOWERBY) el mar de Tethys a través del Corredor Hispano (Schindewolf, 1957: Hillebrandt 1981; Westermann, (Lámina 1, Fotos 3, 4, 5) 1981; Hallam 2001), y, teniendo similares patrones de sedimentación transgresiva, siendo relacionado este Material: Código INGEMMET-6160/1. Un molde de proceso de rift en el Sinemuriano, con la transgresion de ammonite en estado de conservación regular. Hardenbol et al. (1998). Descripción: La concha es evoluta, presenta costillaje Se tomó como referencia el estándar de biozonación tosco, recto y sub-cuadrado. En la parte ventral se observa europea (Page, 2003). Sin embargo, trabajos posteriores que las costillas tienden a ser inclinadas hacia adelante, y de Cecioni & Westermann (1968), Hillebrandt (1981, presentan un ligero engrosamiento a medida que se 1994, 2002) y Quinzio (1987) mencionaron biozonas acercan a la quilla. elaboradas con ejemplares típicos del continente, Bioestratigrafía: Parte superior de la zona de Arietites demostrando un mejor manejo de las biozonas de esta bucklandi (Quinzio, 1987). región por el provincialismo de los ammonites jurásicos Geocronología: Sinemuriano inferior, parte superior provenientes del mar de Tethys. Según los mencionados (192.6 ± 1.5 Ma). investigadores, las biozonas del Sinemuriano, en Sudamérica, están representadas por las zonas de Arietites bucklandi, Arnioceras semicostatum, Caenisites Coroniceras (Coroniceras) cf. rotiforme (SOWERBY) turneri, Asteroceras obtusum, Oxynoticeras oxynotum y (Lámina 1, Fotos 1, 2) Echioceras raricostatum. Las especies Coroniceras brevidorsale y Coroniceras Material: Código INGEMMET-6160/3. Un molde de rotiforme indican la zona de A. bucklandi, que marca el ammonite en regular estado de conservación. Sinemuriano inferior. El taxón Coroniceras reynesi, muy Descripción: Fragmento que presenta la concha evoluta; característico en Europa (Quinzio, 1987), permite se observa costillaje recto y numeroso, que tiende a identificar la zona de A. semicostatum, que indica el inclinarse ligeramente hacia la abertura en la parte Sinemuriano inferior terminal; se encuentra en niveles ventral. Por la conservación regular a mala del ammonite limo-arcillosos por encima de los ammonites identificados es difícil precisar con exactitud si corresponde de la zona de A. bucklandi. Según ello, se puede establecer exactamente a la especie C. rotiforme. el límite de la zona de A. bucklandi en el intervalo medio a Bioestratigrafía: Parte superior de la zona de Arietites superior del Sinemuriano inferior, a partir del cual bucklandi (Quinzio, 1987). aparece Coroniceras reynesi de la zona de A. semicostatum, Cronología: Sinemuriano inferior, parte superior (192.6 que ocurre en los niveles superiores de la Formación ± 1.5 Ma). Aramachay. Boletín de la Sociedad Geológica del Perú, v. 108, p. 213-218 (2013) 215 Lámina 1. Fotos 1 a 9. 216 Boletín de la Sociedad Geológica del Perú, v. 108, p. 213-218 (2013) Figura 2. Columna estratigráfica y sección cronoestratigráfica de la Fm Aramachay entre Yambrasbamba y Pedro Ruiz. Boletín de la Sociedad Geológica del Perú, v. 108, p. 213-218 (2013) 217 4. Conclusiones Cenozoic chronostratigraphy and eustatic cycles. In: Wilgus, C.K., Hastings, B.K., Posamentier, H., Van La presentación de nuevos registros de ammonites del Wagoner, J., Ross, C.A., Kendall, C. (Eds.): Sea-level género Coroniceras, cuyos rangos estratigráficos están changes: An integrated approach, Soc. Econ. Paleont. bien establecidos, indica que la sedimentación de las Mineralog. Spec. Publ., v. 42, p. 71-108. limoarcillitas de la Formación Aramachay en la parte Hallam, A. 2001. A review of the broad pattern of Jurassic norte de los Andes Centrales se prolongó hasta finales del sea-level changes and their possible causes in the light of Sinemuriano inferior. Las especies Coroniceras current knowledge. Palaeogeography, brevidorsale y Coroniceras rotiforme, registradas por Palaeoclimatology, Palaeoecology, v. 167, p. 23-37. primera vez para este sector de la Cordillera Oriental, Hardenbol, J., Thierry, J., Farley, M.B., Jacquin, T., de indican la zona de Arietites bucklandi (Quinzio, 1987), la Graciansky, P.-C., Vail, P.R. 1998. Mesozoic and Cenozoic misma que marca el Sinemuriano inferior. Así como sequence chronostratigraphic framework of European también suprayaciente, se registra al taxón Coroniceras Basins. In: de Graciansky, P.-C., Hardenbol, J., Jacquin, T., reynesi que permite identificar la zona de Arnioceras Vail, P.R. (eds): Mesozoic and Cenozoic Sequence semicostatum (Quinzio, 1987) del Sinemuriano inferior Stratigraphy of European Basins. SEPM Special (parte superior). Se puede establecer el contacto entre las Publication 60, p. 3-14. zonas de A. bucklandi y A. semicostatum en el intervalo Hillebrandt, A. von. 1994. The Triassic/Jurassic boundary medio–superior del Sinemuriano inferior, debido a la and Hettangian biostratigraphy in the area of the desaparición de las especies indicadoras de la primera y la Utcubamba valley (Northern Peru). Geobios, v. 17, p. aparición gradual de los Coroniceras reynesi,
Load more

Recommended publications
  • Felix Gradstein, Lames Ogg and Alan Smith 18 the Jurassic Period J
    Felix Gradstein, lames ogg and Alan smith 18 The Jurassic Period J. G. OGG iographic distribution of Jurassic GSSPs that have been ratified (ye Table 18.1 for more extensive listing). GSSPs for the honds) or are candidates (squares) on a mid-Jurassic map base-Jurassic, Late Jurassic stages, and some Middle Jurassic stages PNS in January 2004; see Table 2.3). Overlaps in Europe have are undefined. The projection center is at 30" E to place the center kured some GSSPs, and not all candidate sections are indicated of the continents in the center of the map. basaurs dominated theland surface. Ammonites are themain fossils neously considered his unit to he older. Alexander Brongniart rmrrelatingmarine deposits. Pangea supercontinent began to break (1829) coined the term "Terrains Jurassiques" when correlat- h md at the end of the Middle Jurassic the Central Atlantic was ing the "Jura Kalkstein" to the Lower Oolite Series (now as- m. Organic-rich sediments in several locations eventually became signed to Middle Jurassic) of the British succession. Leopold t source rocks helping to fuel modern civilization. von Buch (1839) established a three-fold subdivision for the Jurassic. The basic framework of von Buch has been retained as the three Jurassic series, although the nomenclature has var- 8.1 HISTORY AND SUBDIVISIONS ied (Black-Brown-White, Lias-Dogger-Malm, and currently L1.1 Overview of the Jurassic Lower-Middle-Upper). The immense wealth of fossils, particularly ammonites, in hc term "Jura Kalkstein" was applied by Alexander von the Jurassic strata of Britain, France, German5 and Switzer- bmholdt (1799) to a series ofcarhonate shelfdeposits exposed land was a magnet for innovative geologists, and modern con- the mountainous Jura region of northernmost Switzerland, cepts of hiostratigraphy, chronostratigraphy, correlation, and d he first recognized that these strata were distinct from paleogeography grew out of their studies.
    [Show full text]
  • Ichthyosauria, Parvipelvia) from the Lower Jurassic of the Atacama Desert, Northern Chile T
    Journal of South American Earth Sciences 98 (2020) 102459 Contents lists available at ScienceDirect Journal of South American Earth Sciences journal homepage: www.elsevier.com/locate/jsames First temnodontosaurid (Ichthyosauria, Parvipelvia) from the Lower Jurassic of the Atacama Desert, northern Chile T ∗ Rodrigo A. Oteroa,b,c, , Patricio Sepúlvedad a Red Paleontológica U-Chile, Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Av. Las Palmeras, 3425, Santiago, Chile b Consultora Paleosuchus Ltda, Huelén 165 Oficina C, Providencia, Santiago, Chile c Museo de Historia Natural y Cultural del Desierto de Atacama, Parque El Loa S/n, Calama, Chile d GeoBlast S.A, Antonio Bellet 444, Oficina 120, Providencia, Santiago, Chile ARTICLE INFO ABSTRACT Keywords: We describe fragmentary ichthyosaur skull remains of a single individual recovered from Lower Jurassic marine Ichthyosauria strata in northern Chile. The preserved teeth display distinctive features such as a very long, robust and coarsely Lower jurassic infolded roots; as well as low, labio-lingually compressed, large triangular crowns with carinae. Dental features south Pangea are consistent with those of the genus Temnodontosaurus, previously known in the Lower Jurassic of Europe. This Paleobiogeography find represent the first record of a temnodontosaurid ichthyosaur in the southern hemisphere, reinforcing a pattern of faunal interchange between the northern Tethys and southern Panthalassa, prior to the separation of Palabras clave: Laurasia and Gondwana, and before the full establishment of the Caribbean Seway. Ichthyosauria Jurásico Inferior Pangea sur RESUMEN Paleobiogeografía Describimos restos craneales fragmentarios de ictiosaurio pertenecientes a un único individuo, recuperado desde estratos marinos del Jurásico Inferior del norte de Chile.
    [Show full text]
  • 'Cenoceras Islands' in the Blue Lias Formation (Lower Jurassic)
    FOSSIL IMPRINT • vol. 75 • 2019 • no. 1 • pp. 108–119 (formerly ACTA MUSEI NATIONALIS PRAGAE, Series B – Historia Naturalis) ‘CENOCERAS ISLANDS’ IN THE BLUE LIAS FORMATION (LOWER JURASSIC) OF WEST SOMERSET, UK: NAUTILID DOMINANCE AND INFLUENCE ON BENTHIC FAUNAS DAVID H. EVANS1, *, ANDY H. KING2 1 Stratigrapher, Natural England, Rivers House, East Quay, Bridgwater, Somerset, TA6 4YS UK; e-mail: [email protected]. 2 Director & Principal Geologist, Geckoella Ltd, Suite 323, 7 Bridge Street, Taunton, Somerset, TA1 1TG UK; e-mail: [email protected]. * corresponding author Evans, D. H., King, A. H. (2019): ‘Cenoceras islands’ in the Blue Lias Formation (Lower Jurassic) of West Somerset, UK: nautilid dominance and influence on benthic faunas. – Fossil Imprint, 75(1): 108–119, Praha. ISSN 2533-4050 (print), ISSN 2533-4069 (on-line). Abstract: Substantial numbers of the nautilid Cenoceras occur in a stratigraphically limited horizon within the upper part of the Lower Jurassic (Sinemurian Stage) Blue Lias Formation at Watchet on the West Somerset Coast (United Kingdom). Individual nautilid conchs are associated with clusters of encrusting organisms (sclerobionts) forming ‘islands’ that may have been raised slightly above the surrounding substrate. Despite the relatively large numbers of nautilid conchs involved, detailed investigation of their preservation suggests that their accumulation reflects a reduction in sedimentation rates rather than an influx of empty conches or moribund animals. Throughout those horizons in which nautilids are present in relative abundance, the remains of ammonites are subordinate or rare. The reason for this unclear, and preferential dissolution of ammonite conchs during their burial does seem to provide a satisfactory solution to the problem.
    [Show full text]
  • PDF (Español (España))
    Revista Mexicana de Ciencias Geológicas,Caracterización v. 22, núm. de una 1, 2005,nueva p.localidad 97-114 fosilífera, Temapá Hidalgo 97 Caracterización de una nueva localidad fosilífera del Jurásico Inferior con crinoides y amonites en el centro-oriente de México (Temapá, Hidalgo) Carlos Esquivel-Macías1,*, Rita G. León-Olvera2 y Kinardo Flores-Castro3 1 Centro de Investigaciones Biológicas, Universidad Autónoma de Hidalgo, 42184 Pachuca, México. 2 Investigadora Independiente. Presa Salinillas 17-B-106, Colonia Irrigación, 11200 México D.F., México. 3 Centro de Investigaciones en Ciencias de la Tierra, Universidad Autónoma de Hidalgo, 42184 Pachuca, México. * [email protected] RESUMEN El grupo Huayacocotla es conocido por medio de diversos estudios geológicos y paleontológicos. En el presente trabajo se reporta por primera vez una fauna de amonites (Paltechioceras cf. mexicanum, P. rothpletzi, Ortechioceras incaguasiense, Coroniceras? (Metophioceras) aff. conybeari auct., Phylloceras sp., Sulciferites? cf. stenorhynchus) e isocrínidos bentónicos (Isocrinidae) y pseudoplanctónicos (Pentacrinitidae). Estos últimos representan nuevos registros para sedimentos sinemurianos de México. Se consideran los supuestos hábitos de vida para las familias a las que pertenecen las especies de amonites, como dato de referencia sobre el ambiente de depósito. En este afloramiento también se encuentra el bivalvo Posidontis semiplicata y un gasterópodo no identificado. Hay tres tipos de asociaciones fósiles que se encuentran repetidamente en las capas del afloramiento Temapá, perteneciente a la Formación Despí, de tal forma que es posible reconocerlas (1) por la diferencia de diámetro de los amonites que las componen; (2) por la diferente composición faunística entre ellas, que se demuestra con la aplicación del índice de Simpson; y (3) por el grado de fragmentación de las conchas.
    [Show full text]
  • USGS Professional Paper 1739-E
    Studies by the U.S. Geological Survey in Alaska, 2006 U.S. Geological Survey Professional Paper 1739–E A Major Unconformity Between Permian and Triassic Strata at Cape Kekurnoi, Alaska Peninsula: Old and New Observations on Stratigraphy and Hydrocarbon Potential By Robert B. Blodgett1 and Bryan Sralla2 Abstract reconnaissance and oil and gas prospecting dating back to the early 1900s. The impetus for early geologic interest came from A major angular unconformity separates carbonates the recognition of several broad surface anticlines, along with and shales of the Upper Triassic Kamishak Formation from active oil and gas seeps emerging from Jurassic sandstone and an underlying unnamed sequence of Permian agglomerate, siltstone cropping out along the axis of the anticlines. volcaniclastic rocks (sandstone), and limestone near Puale Bay The internal company report by Hanna and others (1937) on the Alaska Peninsula. For the first time, we photographi- makes it apparent that the thick succession of Upper Trias- cally document the angular unconformity in outcrop, as clearly sic carbonates exposed between Puale and Alinchak Bays exposed in a seacliff ~1.3 mi (2.1 km) west of Cape Kekurnoi on the Pacific side of the Alaska Peninsula, directly across in the Karluk C–4 and C–5 1:63,360-scale quadrangles. This Shelikof Strait from Kodiak Island, Alaska (fig. 1), was of unconformity is also documented by examination of core primary interest early on as an exploration target. Work by chips, ditch cuttings, and (or) open-hole electrical logs in two the Standard Oil Co. of California during the 1930s, along deep oil-and-gas-exploration wells (Humble Oil & Refining with encouragement by the famous Alaska oil prospector Co.’s Bear Creek No.
    [Show full text]
  • The Late Triassic and Early Jurassic Succession at Southam Cement Works, Warwickshire Jonathan D
    The late Triassic and early Jurassic succession at Southam Cement Works, Warwickshire Jonathan D. Radley Abstract. Southam Cement Works Quarry, Long Itchington, exposes beds ranging from the Cotham Member of the late Triassic Lilstock Formation up into the Rugby Limestone Member of the early Jurassic Blue Lias Formation. The lithologies and fauna are described and interpreted in the context of Triassic and Jurassic palaeoenvironmental change. Warwickshire’s Jurassic outcrop is dominated by a investigated by Weedon (1986) and Wignall and broad low-lying terrain formed by argillaceous rocks Hallam (1991). Aspects of the palaeontology and of the early Jurassic (Hettangian up to ichnology have been documented by Clements Pliensbachian) Blue Lias and Charmouth Mudstone (1975), Gilliland (1992) and Swift and Martill formations. The Charmouth Mudstone Formation (1999). Jones and Gould (1999) featured Long is poorly exposed, however the upper part of the Itchington material in their important study of Blue Lias Formation (Rugby Limestone Member; oyster (Gryphaea) growth and evolution. Ambrose, 2001) has been extensively quarried for Additionally, the site has been mentioned by several the cement industry. Largely inaccessible sections other workers including Nuttall (1916), Arkell occur in several disused pits, as at Rugby and near (1947) and Hallam (1968). Rocks and fossils from Harbury. the site are held in the collections of Warwickshire Currently (2002) the only working quarry is at Museum. Long Itchington, [NGR SP420630] 10 km E.S.E. of Leamington Spa (Fig. 1). Here, the deep, extensive Lilstock Formation (Langport Member) excavation at Southam Cement Works exposes early Jurassic mudstones and limestones of the Blue Lias The main quarry floor is a broadly planar (but in Formation (Saltford Shale and Rugby Limestone places hummocky) iron-stained surface, marking the members; Hettangian up to Sinemurian; liasicus up eroded top of the Langport Member.
    [Show full text]
  • Characteristic Jurassic Mollusks from Northern Alaska
    Characteristic Jurassic Mollusks From Northern Alaska GEOLOGICAL SURVEY PROFESSIONAL PAPER 274-D Characteristic Jurassic Mollusks From Northern Alaska By RALPH W. IMLAY A SHORTER CONTRIBUTION TO GENERAL GEOLOGY GEOLOGICAL SURVEY PROFESSIONAL PAPER 274-D A study showing that the northern Alaskan faunal succession agrees with that elsewhere in the Boreal region and in other parts of North America and in northwest Europe UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1955 UNITED STATES DEPARTMENT OF THE INTERIOR Douglas McKay, Secretary GEOLOGICAL SURVEY W. E. Wrather, Director For sale by the Superintendent of Documents, U. S. Government Printing Office Washington 25, D. C. - BMMH§ts (paper cover) Price $1.00 CONTENTS Page Abstract_________________ 69 Introduction _________________ 69 Biologic analysis____________ 69 Stratigraphic summary. _______ 70 Ages of fossils________________ 73 Comparisons with other faunas. 75 Ecological considerations___ _ 75 Geographic distribution____. 78 Summary of results ___________ 81 Systematic descriptions__ _. 82 Literature cited____________ 92 Index_____________________ 95 ILLUSTRATIONS [Plates &-13 follow Index] PLATE 8. Inoceramus and Gryphaea 9. Aucella 10. Amaltheus, Dactylioceras, "Arietites," Phylloceras, and Posidonia 11. Ludwigella, Dactylioceras, and Harpoceras. 12. Pseudocadoceras, Arcticoceras, Amoeboceras, Tmetoceras, Coeloceras, and Pseudolioceras 13. Reineckeia, Erycites, and Cylindroteuthis. Page FIGXTKE 20. Index map showing Jurassic fossil collection localities in northern Alaska.
    [Show full text]
  • Pliensbachian Nannofossils from Kachchh: Implications on the Earliest Jurassic Transgressive Event on the Western Indian Margin
    53 he A Rei Series A/ Zitteliana An International Journal of Palaeontology and Geobiology Series A /Reihe A Mitteilungen der Bayerischen Staatssammlung für Paläontologie und Geologie 53 An International Journal of Palaeontology and Geobiology München 2013 Zitteliana Zitteliana A 53 (2013) 105 Pliensbachian nannofossils from Kachchh: Implications on the earliest Jurassic transgressive event on the western Indian margin Jyotsana Rai1 & Sreepat Jain2* Zitteliana A 53, 105 – 120 1Birbal Sahni Institute of Palaeobotany, 53 University Road, 226007, Lucknow, India München, 31.12.2013 2DG–2, Flat no. 52D, SFS Flats, Vikas Puri, New Delhi, 110018, India Manuscript received *Author for correspondence and reprint requests: E-mail: [email protected] 05.04.2013; revision accepted 16.11.2013 ISSN 1612 - 412X Abstract The oldest rocks within the Kachchh Basin belong to the sediments of Kaladongar Formation exposed in Kuar Bet, Pachchham Island (western India). The Formation’s lowest unit, the Dingi Hill Member has yielded a moderately diversified calcareous nannofossil assembla- ge that includes the marker species of Lotharingius contractus and Triscutum sullivanii of late Early Aalenian age associated with reworked species of Biscutum finchii, Bussonius prinsii, Crucirhabdus primulus, Crepidolithus pliensbachensis, Discorhabdus criotus and D. striatus suggesting an age spanning NJ4a to NJ7 Zones (Early Pliensbachian, Tethyan ammonite Jamesoni Zone to Middle Toarcian, Variabilis Zone). Additionally, samples from four other Kachchh domal localities (Kachchh Mainland: Jara, Jumara and Habo and the Island belt, Waagad) have also yielded reworked Pliensbachian-Toarcian age (~183 Ma) nannotaxa viz. Crepidolithus granulatus, Diductius constans, Mazaganella protensa, Mitrolithus elegans, Parhabdolithus liasicus, Similiscutum orbiculus, and Triscutum tiziense. This nannotaxa age is much earlier than the ammonite-based Earliest Bajocian date (~171.6 Ma) based on the presence of ammonite Calliphylloceras hetero- phylloides (Oppel).
    [Show full text]
  • Note on the Ammonite — Bearing Beds in the Various Localities of Turkey - Part One: Ankara Region
    NOTE ON THE AMMONITE — BEARING BEDS IN THE VARIOUS LOCALITIES OF TURKEY - PART ONE: ANKARA REGION Mükerrem TÜRKÜNAL Mineral Research and Exploration Institute of Turkey INTRODUCTION While working on «The Mono- graphic Revision of the Ammonites Fa- una of Turkey» (to be published later), the author has prepared a note on the Ammonite-bearing beds of Turkey. In this note are assembled the data of the available literature on this subject with the listing of fossil names as given by the authors; the synonyms are given here only for a few well-known species. In the Monography, each of these fos- sils will be fully discussed and all the synonyms of the fossils will be given. In the present note, we are beginning with the beds of the Ankara region. The other localities will be the subject of the following notes. LOCALITY : ANKARA In this district, there are several beds known from the early works. The most important ones will be listed below. A - Balkuyumcu. — In 1887, Tchihatcheff (10) studied first this Jurassic outcrop and found concave-fractured limestone. This limestone contains : A. tortisulcatus (= Sowerbyceras tortisulcatum D'Orb.) A. ardennensis (= Peltoceratoides ardennensis D'Orb.) A. plicatilis (= Perisphenctes plicatilis Sow.) A. tatricus (= Phyllocefas tatricum (Pusch) ?) Age. — Oxfordian. 68 Mükerrem TÜRKÜNAL B - Kesiktaş. — Pompeckj (7), in 1897, made a detailed study of the Juras- sic of Ankara. In his book, he mentioned these fossils : Arietites cf. rotator Reynes A. cf. latesulcatus Quens. Aegoceras sp. aff. brevispinae Sow. Phylloceras alontinum frondosum Reynes Ph. hebertinum Reynes His fossil locality must be wrong. Because, according to several authors, no Jurassic series were encountered in the given locality.
    [Show full text]
  • Austroalpine Liassic Ammonites from the Adnet Formation (Northern Calcareous Alps) 163-211 ©Geol
    ZOBODAT - www.zobodat.at Zoologisch-Botanische Datenbank/Zoological-Botanical Database Digitale Literatur/Digital Literature Zeitschrift/Journal: Jahrbuch der Geologischen Bundesanstalt Jahr/Year: 1993 Band/Volume: 136 Autor(en)/Author(s): Meister Christian, Böhm Florian Artikel/Article: Austroalpine Liassic Ammonites from the Adnet Formation (Northern Calcareous Alps) 163-211 ©Geol. Bundesanstalt, Wien; download unter www.geologie.ac.at Jb. Geol. B.-A. ISSN 0016-7800 Band 136 S.163-211 Wien, Juli 1993 Austroalpine Liassic Ammonites from the Adnet Formation (Northern Calcareous Alps) By CHRISTIAN MEISTER & FLORIAN BÖHM *) With 14 Text-Figures and 9 Plates Oslerreich Salzburg Oberöslerreich Nördliche Kalkalpen Lias Ammoniten Oslerreichische Karle 1. 50.000 Biostratigraphie BI/1l1er94, 95, 96,126 Palaeogeographie Contents Zusammenfassung 163 Abstract. .. 164 Resume 164 1. Introduction 164 2. Geographical and Geological Framework 164 3. Lithological Description and Qualitative/Quantitative Ammonite Distributions 165 3.1. Schmiedwirt Quarry 165 3.2. Breitenberg Quarry 166 3.3. Rotkogel Outcrop 166 3.4. Rötelstein Outcrop 168 4. Systematic Palaeontology 169 PhylioceratinaARKELL 1950 171 LytoceratinaHYATT1889 174 Ammonitina HYATT 1889 175 5. Biostratigraphical Framework 184 5.1. Sinemurian 184 5.1.1. Early Sinemurian 184 5.1.2. Late Sinemurian 184 5.2. Pliensbachian 184 5.2.1. Early Pliensbachian (Carixian) 184 5.2.2. Late Pliensbachian (Domerian) 186 5.3. Toarcian 186 6. Faunal Composition and Palaeogeographical Remarks 189 7. Conclusion 190 Acknowledgements 190 References 208 Oberostalpine Liasammoniten aus der Adnetformation (Nördlichen Kalkalpen) Zusammenfassung Das Oberostalpin spielt eine Schlüsselrolle für das Verständnis der Verteilungsmuster der jurassischen Ammonitenfaunen und für die Fixierung genauer biostratigraphischer Korrelationen zwischen Tethyaler und Euroborealer Faunenprovinz.
    [Show full text]
  • Orbital Pacing of the Early Jurassic Carbon Cycle, Black-Shale
    1 Orbital pacing of the Early Jurassic carbon cycle, black-shale 2 formation and seabed methane seepage 3 4 WEIMU XU1*, MICHA RUHL1, STEPHEN P. HESSELBO2, JAMES B. RIDING3 and HUGH C. 5 JENKYNS1 6 1Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, UK (*Correspondence: 7 [email protected]) 8 2Camborne School of Mines, University of Exeter, Penryn TR10 9FE, UK 9 3British Geological Survey, Keyworth, Nottingham NG12 5GG, UK 10 11 12 ABSTRACT 13 The Early Jurassic (~201–174 Ma) was marked by a series of rapid perturbations in climate, 14 the environment, and global geochemical cycles, which have been linked to volcanic 15 outgassing and the release of biogenic or thermogenic methane into the ocean–atmosphere 16 system. The state of the global carbon cycle and prevailing climatic and environmental 17 conditions that existed at this time are, however, poorly constrained. Here, mudrocks of the 18 Lower Sinemurian Arietites bucklandi ammonite Biozone at coastal exposures at Kilve, 19 Somerset, UK have been studied. This succession includes laminated organic-rich black 20 shales, which are present throughout the Bristol Channel Basin, and coincides with a 2–3‰ 21 negative carbon-isotope excursion, distinct changes in inferred land vegetation, and abundant 22 marine prasinophytes (green algae). The event itself does not represent a single perturbation 23 of the regional environment, but follows in a sequence of eccentricity-modulated, precession- 24 paced perturbations that occur throughout the preceding Hettangian stage, with the periodic 25 formation of organic-rich laminated black shales in the Bristol Channel Basin.
    [Show full text]
  • Un Nouveau Genre Et Une Nouvelle Espèce D’Ammonite Micromorphe Dans Le Sinémurien De L’Est De La France (Côte-D’Or)
    Un nouveau genre et une nouvelle espèce d’ammonite micromorphe dans le Sinémurien de l’Est de la France (Côte-d’Or). Jean-Louis Dommergues To cite this version: Jean-Louis Dommergues. Un nouveau genre et une nouvelle espèce d’ammonite micromorphe dans le Sinémurien de l’Est de la France (Côte-d’Or).. Revue de Paléobiologie, Museum d’Histoire Naturelle de la Ville de Geneve, 2015, 34 (1), pp.151-160. 10.5281/zenodo.18905. hal-01184751 HAL Id: hal-01184751 https://hal.archives-ouvertes.fr/hal-01184751 Submitted on 19 Aug 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. REVUE DE VOLUME 34 (1 ) – 2015 PALÉOBIOLOGIE Une institution Ville de Genève www.museum-geneve.ch Revue de Paléobiologie, Genève (juin 2015) 34 (1) : 151-160 ISSN 0253-6730 Un nouveau genre et une nouvelle espèce d’ammonite micromorphe dans le Sinémurien de l’Est de la France (Côte-d’Or) Jean-Louis DOMMERGUES1 1 UFR Sciences de la Vie de la Terre et de l’Environnement, Université de Bourgogne, CNRS/uB, UMR 6282, Biogéo­ sciences Dijon, 6 Boulevard Gabriel, F­21000 Dijon, France.
    [Show full text]