The Lower Cretaceous (Albian) Ammonite Genera Leconteites and Brewericeras

Total Page:16

File Type:pdf, Size:1020Kb

The Lower Cretaceous (Albian) Ammonite Genera Leconteites and Brewericeras The Lower Cretaceous (Albian) Ammonite Genera Leconteites and Brewericeras GEOLOGICAL SURVEY PROFESSIONAL PAPER 503-F The Lower Cretaceous (Albian) Ammonite Genera Leconteites and Brewericeras By DAVID L. JONES, MICHAEL A. MURPHY, and EARLL. PACKARD CONTRIBUTIONS TO PALEONTOLOGY GEOLOGICAL SURVEY PROFESSIONAL PAPER 503-F A report simplifying the complex nomenclature of the ammonite genera Leconteites and Brewericeras UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON 1965 UNITED STATES DEPARTMENT OF THE INTERIOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY Thomas B. Nolan, Director For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price .50 (paper cover) CONTENTS Page Page Abstract___________________________________________ F1 Stratigraphic position and age-Continued Introduction_______________________________________ 1 Central Oregon_________________________________ F5 l'romenclature__________________________________ 1 Queen Charlotte Islands _____________________ -___ 6 Acknowledgments, measurements, and abbreviations ___ ..: 3 Southern Alaska________________________________ 7 Material studied____________________________________ 3 Evolutionary sequence _________________________ - ___ - 8 Systematic descriptions _________________________ -- __ - 9 Stratigraphic position and age of Leconteites and Breweri- ceras________________________________________ 3 References ____________________________________ - - _ _ _ 19 Onoarea______________________________________ 3 Index_____________________________________________ 21 ILLUSTRATIONS [Plates 1-11 follow index] PLATE 1, 3-5. Leconteites lecontei (Anderson). 2. Leconteites lecontei (Anderson) and L. sacramenticus (Anderson). 6. Leconteites lecontei whiteavesi Jones, Murphy, and Packard, n. subsp. and L. deansi (Whiteaves). 7. Leconteites lecontei whiteavesi Jones, Murphy, and Packard, n. subsp. 8. Breuericeras breweri (Gabb) and B. hulenense (Anderson). 9, 10. Brewericeras hulenense (Anderson). 11. Brewericeras hulenense and Leconteites lecontei. Page FIGURE 1. Index map of Ono area, northern California-------------------------------------------------------- F4 2. Generalized diagrammatic columnar sections, Ono area, northern California ___________________________ _ 5 3-5. Index map of- 3. Mitchell area, central Oregon _____________________________________________________________ _ 6 4. Graham Island, Queen Charlotte Islands, B.C----------------------------------------------- 6 5. The upper Chitina Valley, southern Alaska _________________________________________________ _ 7 6. Generalized columnar section, Fohlin Creek area __________________________________________________ _ 8 7. Postulated evolutionary sequence of Leconteites and Brewericeras ____________________________________ _ 8 8. Cross sections of Leconteites lecontei s. s __________________________________________________________ _ 10 9. Scatter diagram showing relation of whorl height to whorl breadth in Leconteites lecontei s. s _____________ _ 11 10. Bar graph showing frequency distribution of Leconteites lecontei s. s ___________________________________ _ 12 11-13. Suture lines of Leconteites lecontei s. s_ ------------------------------------------------------------- 12 14. Scatter diagram, Brewericeras hulenense __________________________________________________________ _ 16 15, 16. Suture lines of Brewericeras hulenense ___________________________________________________________ _ 17 17. Bar graph showing frequency distribution of Brewericeras hulenense ________________________ -- ___ ---_- 18 m CONTRIBUTIONS TO PALEONTOLOGY THE LOWER CRETACEOUS (ALBIAN) AMMONITE GENERA LECONTEITES AND BREWERICERAS By DAVID L. JoNES, MICHAEL A. MuRPHY/ and EARL L. PACKARD 2 ABSTRACT surprisingly Wide range of morphologic variation. Lower Cretaceous (Albian) ammonites from the Pacific coast Studies of the Upper Cretaceous Collignoniceratids by region of North America designated as Leconteites lecontei, L. Haas (1946), the Triassic genus Tropites by Silberling modestum (in part), Puzosigella mulleri, P. tajfi, P. rogersi, and P. (1959), and the mid-Cretaceous genus Neogastroplites perrinsmithi (in part), are herein regarded as forming one highly by Reeside and Cobban (1960) conclusively demon­ variable but intergrading species to which the name L. lecontei (Anderson) is applied. Puzosigella sacramentica (Anderson) is strate that intraspecific variation from finely ribbed regarded as a separate species of Leconteites, and the name compressed individuals to robust coarsely ornamented Puzosigella is rejected. A new subspecies, L. lecontei whiteavesi, forms is normal for some ammonites and that finely is recognized from the Albian beds of Queen Charlotte Islands, drawn taxonomic distinctions based on differences in and one species, L. deansi, is abundant in the lowest Albian beds whorl proportions or strength of ornamentation do of southern Alaska. The genus Brewericeras is regarded as a direct descendant of not hold up when a sufficiently large sample is available. Leconteites and contains two species: B. breweri (Gabb) and B. On the other hand, some groups of ammonites are hulenense (Anderson). B. breweri is known only from one speci­ remarkably constant morphologically and show little men, but B. hulenense is abundant and widespread in upper lower range in variation. Why this difference exists is not Albian deposits. This species shows a wide range in morphologic clear, but it seems probable that the highly variable variation from smooth compressed forms to ribbed slightly inflated forms. species are most important from an evolutionary point of view, as they provide a wider basis upon which INTRODUCTION natural selection can operate to produce separately Ammonites assigned to various species of the genera evolving strains. Leconteites Casey, Puzosigella Casey, and Brewericeras This study attempts to document another example Casey are locally abundant in Albian strata in Cali­ of extreme variation and also to elucidate what seems fornia, Oregon, British Columbia, and Alaska. Because to be a clear evolutionary sequence. of their wide distribution and short geologic range, these ammonites are very useful in correlation, but because of NOMENCLATURE the proliferation in specific names, uncertainty of generic The genera Leconteites and Puzosigella are based on affinities, and obvious synonymy of some of the types, two species, Desmoceras lecontei and Pachydiscus their proper identification is impossible using the present sacramenticus, first named by Anderson (1902). Ac­ nomenclature. cording to Anderson, the former species is characterized Likewise, an apparent evolutionary sequence of the by a compressed whorl section, narrow umbil.i?us, early Albian Leconteites leading to the late early Albian nearly vertical umbilical wall, angular umbilical or early middle Albian Brewericeras has been obscured shoulder, and weak ornamentation; the latter species by placing these two genera in different families: is characterized by a more inflated whorl section, wider Leconteites in Hoplitidae and Brewericeras in Desmo­ umbilicus, sloping umbilical wall, rounded umbilical ceratidae (Wright in Arkell and others, 1957). shoulder and coarse ornamentatiOn. Holotypes of In recent years, studies of large populatiOns of both species' apparently were obtained from the same ammonites have shown that some species exhibit a place on the east fork of Ruling (Hulen) Cree~ near Ono, northern California (California Acad. SCl. loc. 1 University of California, Riverside, Calif. 2 Stanford University, Stanford, Calif. 152, see Anderson, 1902, p. 96, 105; 1938, p. 195, 196). Fl F2 CONTRIBUTIONS TO PALEONTOLOGY Hall and Ambrose (1916, p. 69; see Wiedey, 1929, p. 25, A study of large collections of ammoni ties from pl. 2, fig. 2) subsequently named a new species, Son­ Oregon, California, British Columbia, and Alaska have neratia rogersi, a closely related form obtained from convinced the authors of this paper that the differen­ Tesla quadrangle in central California. Anderson tiation of leconteitid and puzosigellid ammonites into (1 938, p. 192, 1 93) later referred Desmoceras lecontei six species and two genera is untenable and that the to Cleoniceras and named a new species, C. modestum, generic differences expressed by Casey and by Imlay which was also obtained from Ruling Creek (Cali­ are invalid. Specimens from a single locality show a fornia Acad. Sci. loc. 1668). In the same publication, complete gradation from compressed finely ornamented Anderson (1938, p. 184, 195) referred Pachydiscus forms (Leconteites) to the more inflated coarsely ribbed sacramenticus to the genus Sonneratia and named as forms (Puzosigella). This same range of variation can new species S. perrinsmithi, S. tajji, and S. mulleri be demonstrated to occur throughout the entire strati­ all of which, together with plesiotypes of S. rogersi, graphic interval in which these forms occur. Thus only were obtained from the east fork of Ruling Creek one generic name should be applied to this entire (California Acad. Sci. loc. 152). morphologic plexus. Casey (1954) recognized that none of the species The genus Brewericeras was named by Casey (1954, cited above belong to either Cleoniceras or Sonneratia, p. 112), who cited Ammonites breweri Gabb as type and he therefore erected two new genera, Lecunteites species. Ammonites breweri was originally based on a and Puzosigella, and D. lecontei and P. sacramenticus, large fragment (UC 12098) figured by
Recommended publications
  • On the Barremian - Lower Albian Stratigraphy of Colombia
    On the Barremian - lower Albian stratigraphy of Colombia Philip J. Hoedemaeker Hoedemaeker, Ph.J. 2004. On the Barremian-lower Albian stratigraphy of Colombia. Scripta Geologica, 128: 3-15, 3 figs., Leiden, December 2004. Ph.J. Hoedemaeker, Department of Palaeontology, Nationaal Natuurhistorisch Museum, P.O. Box 9517, 2300 RA Leiden, The Netherlands (e-mail: hoedemaeker@naturalis.nnm.nl). Key words – stratigraphy, Barremian, Aptian, depositional sequences, Colombia. The biostratigraphy and sequence stratigraphy of the Barremian deposits, and the biostratigraphy of the Aptian deposits in the Villa de Leyva area in Colombia are briefly described. Contents Introduction ....................................................................................................................................................... 3 Barremian ............................................................................................................................................................ 4 Barremian sequence stratigraphy ............................................................................................................ 6 Aptian ................................................................................................................................................................. 11 Lowermost Albian ........................................................................................................................................ 13 Conclusions ....................................................................................................................................................
    [Show full text]
  • GSSP) for the Base of the Cenomanian Stage, Mont Risou, Hautes-Alpes, France
    21 by W.J. Kennedy1, A.S. Gale2, J.A. Lees3, and M. Caron4 The Global Boundary Stratotype Section and Point (GSSP) for the base of the Cenomanian Stage, Mont Risou, Hautes-Alpes, France 1 Oxford University Museum of Natural History, Parks Road, Oxford OX1 3PW, U.K. 2 Department of Palaeontology, The Natural History Museum, Cromwell Road, London SW7 5BP, U.K. and School of Earth and Environ- mental Sciences, University of Greenwich, Chatham Maritime Campus, Chatham, Kent ME4 4AW, U.K. 3 Research School of Geological and Geophysical Sciences, Birkbeck College and University College London, Gower Street, London WC1E 6BT, U.K. 4 Institut de Géologie, Université de Fribourg, CH-1700 Fribourg, Switzerland. Following the unanimous recommendation of the Inter- Grès Vert Supérieur etc., and taking the name from Touraine national Commission on Stratigraphy, the Global (Roman Turonia). Five years later, he realized that two distinct ammonite and rudist faunas were present, and he restricted the term boundary Stratotype Section and Point (GSSP) for the Turonian to beds corresponding to his third zone of rudists, yielding base of the Cenomanian Stage is defined at a level 36 “Ammonites lewesiensis, peramplus, Vielbancii, Woolgari, Fleuri- metres below the top of the Marnes Bleues Formation, a ausianus, Deverianus etc.”, “le plus beau type côtier étant très prononcé dans toute la Touraine, et nous donnerons à la partie level that corresponds to the the first appearance of the inférieure le nom d’étage Cénomanien, le Mans (Cenomanum), en planktonic foraminiferan Rotalipora globotruncanoides montrant à la fois le type sous-marin” (d'Orbigny, 1848–1851, p.
    [Show full text]
  • ALBIAN AMMONITES of POLAND (Plates 1—25)
    PALAEONTOLOGIA POLQNICA mm ■'Ъ-Ь POL T S H ACADEMY OF SCIENCES INSTITUTE OF PALEOBIOLOGY PALAEONTOLOGIA POLONICA—No. 50, 1990 t h e a l b ia w AMMONITES OF POLAND (AMQNITY ALBU POLS К I) BY RYSZARD MARCINOWSKI AND JOST WIEDMANN (WITH 27 TEXT-FIGURES, 7 TABLES AND 25 PLATES) WARSZAWA —KRAKÔW 1990 PANSTWOWE WYDAWNICTWO NAUKOWE KEDAKTOR — EDITOR JOZEP KA2MIERCZAK 2ASTEPCA HEDAKTOHA _ ASSISTANT EDITOR m AôDAlenA BÛRSUK-BIALYNICKA Adres Redakcjl — Address of the Editorial Office Zaklad Paleobiologij Polska Akademia Nauk 02-089 Warszawa, AI. 2w irki i Wigury 93 KOREKTA Zespol © Copyright by Panstwowe Wydawnictwo Naukowe Warszawa — Krakôw 1990 ISBN 83-01-09176-2 ISSN 0078-8562 Panstwowe Wydawnielwo Naukowe — Oddzial w Krakowie Wydanie 1, Naklad 670 + 65 cgz. Ark. wyd. 15. Ark. druk. 6 + 25 wkladek + 5 wklejek. Papier offset, sat. Ill kl. 120 g. Oddano do skiadania w sierpniu 1988 r. Podpisano do druku w pazdzierniku 1990 r. Druk ukoriczono w listopadzie 1990 r. Zara. 475/87 Drukarnia Uniwersytetu Jagielloriskiego w Krakowie In Memory of Professor Edward Passendorfer (1894— 1984) RYSZARD MARCINOWSKI and JOST WIEDMANN THE ALBIAN AMMONITES OF POLAND (Plates 1—25) MARCINOWSKI, R. and WIEDMANN, J.: The Albian ammonites of Poland. Palaeonlologia Polonica, 50, 3—94, 1990. Taxonomic and ecological analysis of the ammonite assemblages, as well as their general paleogeographical setting, indicate that the Albian deposits in the Polish part of the Central European Basin accumulated under shallow or extremely shallow marine conditions, while those of the High-Tatra Swell were deposited in an open sea environment. The Boreal character of the ammonite faunas in the epicontinental area of Poland and the Tethyan character of those in the Tatra Mountains are evident in the composition of the analyzed assemblages.
    [Show full text]
  • Stratigraphic Implications of a New Lower Cretaceous Ammonoid Fauna from the Puez Area (Valanginian – Aptian, Dolomites, Southern Alps, Italy)
    Geo.Alp, Vol. 3, S. 55–83, 2006 STRATIGRAPHIC IMPLICATIONS OF A NEW LOWER CRETACEOUS AMMONOID FAUNA FROM THE PUEZ AREA (VALANGINIAN – APTIAN, DOLOMITES, SOUTHERN ALPS, ITALY) Alexander Lukeneder1 & Christian Aspmair2 With 6 figures and 8 plates 1 Natural History Museum, Geological-Palaeontological Department, Burgring 7, A-1010 Wien, Austria, e-mail: alexander.lukeneder@nhm-wien.ac.at 2 Prissian 102, I – 39010 Tisens (BZ), Italy Abstract Lower Cretaceous ammonoids (n = 424) were collected at the Puez locality in the Dolomites of Southern Tyrol. The cephalopod fauna from the marly limestones to marls here indicates Late Valanginian to Early Aptian age. The deposition of the marly limestones and marls of this interval occurred during depositional- ly unstable conditions. The underlying Biancone Formation (Maiolica Formation) is of Early Valanginian, whereas the lowermost Rosso Ammonitico is of Jurassic to Berriasian age. The ammonoid fauna consists of 27 different genera, each represented by 1-2 species. The assemblage at the Puez section is dominated by the Phylloceratina (30%) and the Ammonitina (34%). Phyllopachyceras (17%) and Phylloceras (13%) (both Phylloceratina) are the most frequent components, followed by Lytoceras (12%) (Lytoceratina), and Barremites (10%) and Melchiorites (8%) (both Ammonitina). The cephalopod fauna is purely of Mediterranean origin. Zusammenfassung Unterkreide Ammonoideen (424 Exemplare) der Puez Lokalität in den Dolomiten Süd-Tirols wurden unter- sucht. Die Fauna der mergeligen Kalke und Mergel von Puez zeigen ein Alter von Ober-Valanginium bis Unter-Aptium an. Die mergeligen Kalke und Mergel dieses Abschnitts lagerten sich unter instabiler Bedingungen ab. Die unterlagernde Biancone Formation (Maiolica Formation) zeigt Unter-Valanginium an, wogegen die tiefste Formation des Rosso Ammonitico auf Ober-Jura bis Berriasium hindeutet.
    [Show full text]
  • Stratigraphy and General Geology of Jke Mccarthy C-5 Quadrangle; Alaska
    Stratigraphy and General Geology of jke McCarthy C-5 Quadrangle; Alaska By E. M. MAcKEVETT, JR. Descriptions of the rocks of a quadrangle famous for its copper mines UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1971 UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY William T. Pecora, Director Library of Congress catalog-card No. 79-609946 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price 30 cents (paper cover) CONTENTS Page Abstract . .....-.. .... ........_.. .. .. .. .. .. .. 1 Introduction ...-. ..... .... .... .. .. ... .. ._. 1 Geology -. ... _. __ .._____ _ . _ __.. _ __. ____. 4 General summary, regional setting, and structure......................... __...... 4 Stratigraphy and lithology . ... __. _ . 8 Hasen Creek Formation .. .. _ . ._.. 8 Nikolai Greenstone ..__ ......_ . _ 8 Chitistone Limestone ... .... ._ . __ _... _ _ _ . 10 Nizina Limestone . .... _ .. .._._ _..._ . _. 11 McCarthy Formation ._ . ... 13 Lower member ...... _...__. __ _ . ._ . _ ._ 13 Upper member . _ .. __. _ .. 14 Lubbe Creek Formation _. __ .. 15 Nizina Mountain Formation .. _ . _-- . .. 16 Root Glacier Formation . __. ._.. ..__ . .. 17 Kennicott Formation .. .__. _. ___ ___. _ ' ._ 19 Schulze Formation ..._... ___ __.. 20 Moonshine Creek Formation _.. ... _ 20 Frederika Formation .. _. .. _. _. 21 Intrusive rocks . .. _. .._... .. 23 Andesitic dikes and sills. ......................... ,.._ . .................. 23 Intermediate rocks ......................................-.......-..^.....................-.
    [Show full text]
  • 12. Lower Cretaceous Ammonites from the South Atlantic Leg 40 (Dsdp), Their Stratigraphic Value and Sedimentologic Properties
    12. LOWER CRETACEOUS AMMONITES FROM THE SOUTH ATLANTIC LEG 40 (DSDP), THEIR STRATIGRAPHIC VALUE AND SEDIMENTOLOGIC PROPERTIES Jost Wiedmann and Joachim Neugebauer, Geol.-palaont. Institut der Universitat Tubingen, BRD ABSTRACT Eleven ammonites have been cored during Leg 40. They were found concentrated in the lower parts of the drilled section at Sites 363 (Walvis Ridge) and 364 (Angola Basin), and permit recognition of upper Albian, middle Albian, and upper Aptian. So far, no lower Albian could be recognized. A high ammonite density can be assumed for the South Atlantic Mid-Cretaceous. In contrast to data available so far, the Walvis Ridge associations consisting of phylloceratids and desmoceratids show more open- basin relationships than those of the Angola Basin, which are composed of mortoniceratids, desmoceratids, and heteromorphs. Paleobiogeographically, the South Atlantic fauna can be related to the well-known onshore faunas of Angola, South Africa, and Madagascar as well as to the European Mid-Cretaceous. This means that the opening of the South Atlantic and its connection with the North Atlantic occurred earlier as was generally presumed, i.e., in the middle Albian. Records of lower Aptian ammonite faunas from Gabon and Brazil remain doubtful. High rates of sedimentation prevailed especially in the Aptian and Albian, in connection with the early deepening of the South Atlantic basins. The mode of preservation of the ammonites suggests that they were deposited on the outer shelf or on the upper continental slope and were predominantly buried under sediments of slightly reducing conditions. In spite of a certain variability of the depositional environment, the ammonites show a uniform and particular mode of preservation.
    [Show full text]
  • Geological Survey Canada
    1-32 GEOLOGICAL PAPER 70-32 SURVEY OF CANADA DEPARTMENT OF ENERGY, MINES AND RESOURCES BROCK RIVER MAP-AREA, DISTRICT OF MACKENZIE (97 D) (Report, 6 figures, 2 tables and P.S. Map 13-1970) H. R. Balkwill and C. J. Yorath Price, $2.00 1970 GEOLOGICAL SURVEY OF CANADA CANADA PAPER 70-32 BROCK RIVER MAP-AREA, DISTRICT OF MACKENZIE (97 D) H. R. Balkwill and C. J. Yorath DEPARTMENT OF ENERGY, MINES AND RESOURCES @)Crown Copyrights reserved Available by mail from Information Canada, Ottawa from the Geological Survey of Canada 601 Booth St., Ottawa and Information Canada bookshops in HALIFAX - 1735 Barrington Street MONTREAL - 1182 St. Catherine Street West OTTAWA - 171 Slater Street TORONTO - 221 Yonge Street WINNIPEG - 499 Portage Avenue VANCOUVER - 657 Granville Street or through your bookseller Price: $2.00 Catalogue No. M:44-70-32 Price subject to change without notice Information Canada Ottawa 1971 - iii - CONTENTS Page Abstract.............................. ...... ................ ... ....... v Introduction . 1 Physiography . 1 Stratigraphy . 5 Proterozoic.............. 8 Shaler Group . • . 8 Diabase sills and dykes . 11 Age and correlation of Proterozoic rocks . 11 Paleozoic . 12 Old Fort Island Formation . 12 Mount Cap Formation . .. 13 Saline River Formation . 15 'Ronning Group' . 15 Bear Rock Formation . 16 Cretaceous . 17 •Silty zone' . 18 1Benton°itic zone' . 18 Age and correlation of Cretaceous rocks . 18 Quaternary . 19 Structural Geology...... 19 Coppermine Arch . 19 Horton Plain and Wollaston structural basin . 20 Structural control of topography . 21 Economic Geology ..................... ........................ ·. 21 Addendum . 22 References 23 Illustrations Map 13- 1970: Geology, Brock River area (97D), District of Mackenzie ..... in pocket Table 1. Table of map-units .
    [Show full text]
  • The Cretaceous of North Greenland
    ZOBODAT - www.zobodat.at Zoologisch-Botanische Datenbank/Zoological-Botanical Database Digitale Literatur/Digital Literature Zeitschrift/Journal: Zitteliana - Abhandlungen der Bayerischen Staatssammlung für Paläontologie und Histor. Geologie Jahr/Year: 1982 Band/Volume: 10 Autor(en)/Author(s): Birkelund Tove, Hakansson Eckhart Artikel/Article: The Cretaceous of North Greenland - a stratigraphic and biogeographical analysis 7-25 © Biodiversity Heritage Library, http://www.biodiversitylibrary.org/; www.zobodat.at 7 Zitteliana 10 7-25 München, 1. Juli 1983 ISSN 0373-9627 The Cretaceous of North Greenland - a stratigraphic and biogeographical analysis By TOVE BIRKELUND & ECKART HÄKANSSON*) With 6 text figures and 3 plates ABSTRACT Mapping of the Wandel Sea Basin (81-84°N) has revealed realites, Peregrinoceras, Neotollia, Polyptycbites, Astieripty- an unusually complete Late Jurassic to Cretaceous sequence chites) are Boreal and Sub-Boreal, related to forms primarily in the extreme Arctic. The Cretaceous pan of the sequence in­ known from circum-arctic regions (Sverdrup Basin, Svalbard, cludes marine Ryazanian, Valanginian, Aptian, Albian, Tu­ Northern and Western Siberia), but they also have affinities to ranian and Coniacian deposits, as well as outliers of marine occurrences as far south as Transcaspia. The Early Albian Santonian in a major fault zone (the Harder Fjord Fault Zone) contains a mixing of forms belonging to different faunal pro­ west of the main basin. Non-marine PHauterivian-Barremian vinces (e. g. Freboldiceras, Leymeriella, Arctboplites), linking and Late Cretaceous deposits are also present in addition to North Pacific, Atlantic, Boreal/Russian platform and Trans­ Late Cretaceous volcanics. caspian faunas nicely together. Endemic Turonian-Coniacian Scapbites faunas represent new forms related to European An integrated dinoflagellate-ammonite-5«c/;D stratigra­ species.
    [Show full text]
  • Mineralogical Characteristics and Geological Significance of Albian (Early Cretaceous) Glauconite in Zanda, Southwestern Tibet, China
    Clay Minerals, (2012) 47, 45–58 Mineralogical characteristics and geological significance of Albian (Early Cretaceous) glauconite in Zanda, southwestern Tibet, China 1 2, 2 2 XIANG LI , YUANFENG CAI *, XIUMIAN HU , ZHICHENG HUANG AND JIANGANG WANG2 1 Wuhan Institute of Geology and Mineral Resources, China Geological Survey, Wuhan 430223, China, and 2 State Key Laboratory for Mineral Deposits Research (Nanjing University), School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, China (Received 27 November 2010; revised 9 September 2011; Editor: George Christidis) ABSTRACT: Early Cretaceous glauconite from the Xiala section, southwestern Tibet, China, was investigated by petrographic microscopy and scanning electron microscopy (SEM), X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy, and electron probe microanalysis (EPMA). The investigations revealed that the glauconite in both sandstones and limestone is highly evolved. The glauconite in sandstone is autochthonous, but in limestone it may be derived from the underlying glauconitic sandstone. Based on analyses of the depositional environments and comparisons of glauconite-bearing strata in Zanda with sequences in adjacent areas, we conclude that the glauconitization at Zanda was probably associated with rising sea levels during the Late Albian, which represent the final separation of the Indian continent from the Australian-Antarctic continent. After the separation of the Indian continent from the Australian- Antarctic continent, cooling of the Indian continent resulted in subsidence and northward subduction of the Indian plate. A gradually rising sea level in Zanda, located along the northern margin of the Indian continent, was the cause of the low sedimentation rate. Continued transgression resulted in the occurrence of the highly evolved glauconite in this area.
    [Show full text]
  • Lower Jaws of Two Species of Menuites (Pachydiscidae, Ammonoidea) from the Middle Campanian (Upper Cretaceous) in the Soya Area, Northern Hokkaido, Japan
    Bull. Natl. Mus. Nat. Sci., Ser. C, 45, pp. 19–27, December 27, 2019 Lower jaws of two species of Menuites (Pachydiscidae, Ammonoidea) from the middle Campanian (Upper Cretaceous) in the Soya area, northern Hokkaido, Japan Kazushige Tanabe1* and Yasunari Shigeta2 1 University Museum, The University of Tokyo, Hongo 7–3–1, Bunkyo Ward, Tokyo 113–0033, Japan 2 Department of Geology and Paleontology, National Museum of Nature and Science, 4–1–1 Amakubo, Tsukuba, Ibaraki 305–0005, Japan * Author for correspondence: tanabe@um.u-tokyo.ac.jp Abstract The lower jaws of two pachydiscid ammonites Menuites soyaensis (Matsumoto and Miyau- chi) and Menuites sp. are described on the basis of two specimens from the middle Campanian (Upper Cretaceous) in the Soya area of northern Hokkaido, Japan. They are preserved in situ in the body cham- ber and characterized by a widely open outer lamella with a nearly flat rostral portion. The outer lamella consists of an inner “chitinous” layer sculptured by a median furrow in the anterior to mid-portions and an outer calcareous layer with prismatic microstructure. The lower jaw features of the two Menuites spe- cies are shared by other species of the Pachydiscidae described in previous works, indicating that they are diagnostic characters of this family. In view of the shovel-like shape without a pointed rostrum, the lower jaws of the two Menuites species were likely used as a scoop to feed on microorganisms. Key words: pachydiscid ammonites, middle Campanian, lower jaw, Soya area (Hokkaido) found together retaining their original life orienta- Introduction tion. Based on such well-preserved specimens and Both modern and extinct cephalopod mollusks their comparison with the jaws of modern cephalo- possess a well-developed jaw apparatus that con- pods, previous authors (e.g.
    [Show full text]
  • The Barremian Heteromorph Ammonite Dissimilites from Northern Italy: Taxonomy and Evolutionary Implications
    The Barremian heteromorph ammonite Dissimilites from northern Italy: Taxonomy and evolutionary implications ALEXANDER LUKENEDER and SUSANNE LUKENEDER Lukeneder, A. and Lukeneder, S. 2014. The Barremian heteromorph ammonite Dissimilites from northern Italy: Taxon- omy and evolutionary implications. Acta Palaeontologica Polonica 59 (3): 663–680. A new acrioceratid ammonite, Dissimilites intermedius sp. nov., from the Barremian (Lower Cretaceous) of the Puez area (Dolomites, northern Italy) is described. Dissimilites intermedius sp. nov. is an intermediate form between D. dissimilis and D. trinodosum. The new species combines the ribbing style of D. dissimilis (bifurcating with intercalating single ribs) with the tuberculation style of D. trinodosum (trituberculation on entire shell). The shallow-helical spire, entirely comprising single ribs intercalated by trituberculated main ribs, is similar to the one of the assumed ancestor Acrioceras, whereas the increasing curvation of the younger forms resembles similar patterns observed in the descendant Toxoc- eratoides. These characters support the hypothesis of a direct evolutionary lineage from Acrioceras via Dissimilites to Toxoceratoides. D. intermedius sp. nov. ranges from the upper Lower Barremian (Moutoniceras moutonianum Zone) to the lower Upper Barremian (Toxancyloceras vandenheckii Zone). The new species allows to better understand the evolu- tion of the genus Dissimilites. The genus appears within the Nicklesia pulchella Zone represented by D. duboise, which most likely evolved into D. dissimilis. In the Kotetishvilia compressissima Zone, two morphological forms developed: smaller forms very similar to Acrioceras and forms with very long shaft and juvenile spire like in D. intermedius sp. nov. The latter most likely gave rise to D. subalternatus and D. trinodosum in the M.
    [Show full text]
  • On the Supposed Aptian Occurrence of the Ammonite Genus Neodeshayesites in Colombia and Venezuela; with an Appendix on Neodeshayesites JL Karsteni (Marcou)
    On the supposed aptian occurrence of the ammonite genus Neodeshayesites in Colombia and Venezuela; with an appendix on Neodeshayesites JL Karsteni (Marcou). ™W FERNANDO ETAYO SERNA1 • I—RESUMEN El genero norandino de amonitas Neodeshayesites, ha sido encontrado asociado con otros generos de amonitas, que forma parte de una fauna del Albiano inferior o Albiano medio basal. El registro de este genero en capas supuestamente de edad aptiana se basa en datos sin apoyo estratigraf ico o en el listado conjunto de faunas procedentes de diferentes localidades. ABSTRACT— Where associated with other ammonites Neodeshayesites, a group of Northern South American species, forms part of a Lower Albian or basal Middle Albian fauna. The supposed record of the genus from Aptian strata is based on inconclusive stratigraphical data or falacious listing of faunas from diff­ erent localities. CONSIDERATIONS ON THE SO-CALLED APTIAN could also be explained as a condensed deposit. However, OCCURRENCE OF NEODESHAYESITES all the other criteria for a condensed deposit are missing.." In 1954, E. Rod and W. Maync published a "Revision of At time of publication of Rod and Maync's paper, no the Lower Cretaceous Stratigraphy of Venezuela"; in part I precise knowledge existed on the stratigraphic position of of this paper (p. 207-208) Rod stressed that he himself the group of species described by Riedel (1938, p 37-40), had". isolated a specimen looking like a Douvilleiceras under Deshayesites. When proposing the .genus Neodeshaye­ out of a Deshayesites pavement of a big concretion. the sites for the same group of species, Casey chose "Deshaye­ Douvilleiceras indicates Lower Albian age and the Deshaye­ sites stutzeri Riedel" as type species (1964, p.
    [Show full text]