DOCSLIB.ORG

Middle Jurassic (Bajocian and Bathonian) Ammonites from Northern Alaska

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Middle Jurassic (Bajocian and Bathonian) Ammonites from Northern Alaska Middle Jurassic (Bajocian and Bathonian) Ammonites From Northern Alaska GEOLOGICAL SURVEY PROFESSIONAL PAPER 854 Middle Jurassic (Bajocian and Bathonian) Ammonites From Northern Alaska By RALPH W. IMLAY GEOLOGICAL SURVEY PROFESSIONAL PAPER 854 An ammonite succession nearly identical ivith that in northern Canada is correlated with a more varied ammonite succession in southern Alaska UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1976 UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY V. E. McKelvey, Director Library of Congress Cataloging in Publication Data Imlay, Ralph Willard, 1908- Middle Jurassic (Bajocian and Bathonian) ammonites from northern Alaska. (Geological Survey professional paper; 854) Bibliography: p. Includes index. Supt. of Docs. no. : I 19.16:854 1. Ammonoidea. 2. Paleontology Jurassic. 3. Paleontology Alaska. I. Title. II. Series: United States. Geo­ logical Survey. Professional paper; 854. QE807.A5I615 564'.53'097987 74-20556 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington D.C. 20402 Stock Number 024-001-027305 CONTENTS Page Abstract __________________. 1 Introduction ________________. 1 Biologic analysis ____________. 1 Stratigraphic summary ________. 2 Stratigraphic distribution of ammonites 3 Ages and correlations __________. 5 Bajocian ammonites ________. 5 Bathonian ammonites _______ 7 Ammonite faunal setting _______. 7 Geographic distribution ______ __ _- 7 Systematic descriptions _________ 10 References cited ___________ ____ . 18 Index __________________. 21 ILLUSTRATIONS [Plates follow index] PLATE 1. Pseudolioceras, Canavarella, Oppelia (Liroxyites), Arkellocerasl, and Arkelloceras. 2. Cranocephalites and Choffatial. 3. Arcticoceras, Arcticocerasl, and Erycitoides. 4. Arctocephalites and Choffatial. Page FIGURE 1. Diagram showing occurrences and ages of fossils in Kingak Shale exposed on Canning River west of Shublik Island, northern Alaska ______-_ __________ 4 2. Chart showing correlation of Bajocian and Bathonian faunas in northern Alaska _ 6 3. Generalized index map of Bajocian ammonite localities in northern Alaska _ _ -______ 11 4. Generalized index map of Bathonian ammonite localities in northern Alaska _______________________ 12 5. Detailed index map of Middle Jurassic ammonite localities in central part of Mt. Michelson quadrangle between the Canning and Sadlerochit Rivers ____________ 13 TABLES Page TABLE 1. Ammonite genera and subgenera of Bajocian and Bathonian Age in northern Alaska _______________ 1 2. Stratigraphic position and age of fossils in Kingak Shale exposed on northwest slope of Ignek Mesa, northern Alaska ______________________ _ _ __- 3. Geographic distribution of ammonites of Bajocian and Bathonian Age in northern Alaska ____ ____ 4. Description of some Middle Jurassic fossil localities in northern Alaska - III MIDDLE JURASSIC (BAJOCIAN AND BATHONIAN) AMMONITES FROM NORTHERN ALASKA By RALPH W. IMLAY ABSTRACT in order to present the latest available evidence con­ Middle Jurassic ammonites of Bajocian and Bathonian cerning the stratigraphic and geographic distribu­ Age occur in northern Alaska within the Kingak Shale tion of the taxa and to show that the Bathonian throughout thicknesses ranging from 300 to 850 feet (90- 255 m) or more. Bajocian ammonites have been identified as Stage is well developed in northern Alaska. Much of far west as the Point Barrow area. Bathonian ammonites the discussion concerning the Bajocian ammonites have -been identified as far west as the Canning River and is a reinterpretation of the fossils described by the are possibly present on the Saviukviayak River. writer in 1955, but the discussion also includes some The Bajocian ammonite succession from the base upward new fossil and stratigraphic data. All these new consists of (1) Pseudolioceras maclintoeki (Haughton); (2) P. whiteavesi (White) in association with Erycitoides data, as well as most of the data concerning Bath­ howeUi (White) and Canavarella crassifalcata Imlay, n. sp.; onian ammonites, are based on fossils collected since and (3) ArkeUoceras cf. A. tozeri Frebold. P. maclintoeki in 1955 by geologists of British Petroleum (Alaska), northern Canada occurs at or near the base of the lower Inc., in 1964, by consulting geologist Marvin Man- Bajocian; P. whiteavesi and E. howelli in southern Alaska gus in 1963 and 1966, and by U.S. Geological Survey occur at the top of the lower Bajocian; and ArkeUoceras on geologists R. L. Detterman in 1969-72 and H. N. the Alaska Peninsula occurs above ammonites representing the Sonninia sowerbyi zone and near the base of an am­ Reiser in 1970. The author is grateful to all these monite sequence representing the Otoites sauzei zone. The geologists for collecting the fossils, for preparing lack of younger Bajocian ammonites anywhere in northern accurate locality maps and descriptions, and for Alaska is indicative of an unconformity. furnishing stratigraphic data. The Bathonian ammonite succession from the base upward consists of (1) Cranocephalites sp., (2) C. iguekensis Imlay, BIOLOGIC ANALYSIS n. sp., (3) Arctocephalites cf. A. elegans Spath, and (4) Arcticoceras ishmae (Keyserling). These ammonites, in com­ Northern Alaska ammonites of Bajocian and parison with the Bathonian ammonite succession in East Bathonian Age that are discussed herein number Greenland, do not represent the highest and lowest parts of 220 specimens. Their distribution by genus, sub­ the stage, as defined for Greenland, nor do they represent family, and family is shown in table 1. Among the the zone of Arctocephalites greenlandicus just below the zone of Arcticoceras ishmae. Perhaps the lack of representation on Ignek Mesa and elsewhere may be partly due to poor TABLE 1. Ammonite genera and subgenera of Bajocian and exposures. Nonetheless, an unconformity at the top of the Bathonian Age in northern Alaska Bathonian sequence in northern Alaska is indicated by the Genus and Number of nearness of Arcticoceras to the early Oxfordian ammonite Family Subfamily subgenus specimens Cardioceras on Ignek Mesa and by the scarcity of definite Hildoceratidae ____ Harpoceratinae _______ Pseudolioceras ___ 65 Callovian ammonites in northern Alaska. 2 25 The Bajocian and Bathonian ammonite faunules in north­ Hammatoceratidae _ Hammatoceratinae ____ 7 Erycitoides? _____ 5 ern Alaska are closely similar to those in northern Canada Oppeliidae ________ Oppeliinae __-----__-- Oppelia and lived in the same faunal province. The inclusion of (Liroxyites) ___ 1 46 some species in common with faunules of the same ages in Cranocephalites 22 Arctocephalites __ 16 southern Alaska shows that the northern and southern seas Arctocephalites? _ 6 were connected, although specifically the northern Alaskan Arcticoceras _____ 24 Perisphinctidae ___ Pseudoperisphinctinae _ 1 faunas are much less varied. New species described herein include Canavarella crassi­ falcata Imlay and Cranocephalites ignekensis Imlay. families, the Hildoceratidae composes two-fifths, the Cardioceratidae nearly one-third, and the Stephano­ INTRODUCTION ceratidae one-fifth of the total specimens. The Hil­ Middle Jurassic ammonites, representing the Ba­ doceratidae is represented mostly by Pseudolioceras jocian and Bathonian Stages, are described herein but also includes Tmetoceras and Canavarella. The BAJOCIAN AND BATHONIAN AMMONITES FEOM NOETHEEN ALASKA Cardioceratidae is represented by nearly equal num­ Canavarella in England is recorded from the zone bers of Arcticoceras, Arctocephalites, and Crano­ of Tmetoceras scissum (Arkell and others, 1957, p. cephalites. L262) near the base of the Middle Jurassic. In The characteristics of most of the genera and sub- northern Alaska, it is associated with Pseudolio­ genera present have been adequately discussed in ceras whiteavesi (White) and Erycitoides cf. E. fairly recent publications. Pseudolioceras, Tmeto- howelli (White). ceras, and Erycitoides have been discussed by West- ermann (1964, p. 358-360, 426-432; 1969, p. 18, STRATIGRAPHIC SUMMARY 52) ; Liroxyites, by Imlay (1962b, p. A8) ; Arkello- ceras, by Frebold (1958, p. 9; 1961, p. 8-10; Fre- Middle Jurassic beds in northern Alaska have bold and others, 1967, p. 18-20) ; Cranocephalites been identified faunally in the subsurface of the and Arctocephalites, by Spath (1932, p. 14-16, 32, Point Barrow-Cape Simpson area (Imlay, 1955, p. 33), Arkell and others (1957, p. L301), and Imlay 82, 89), in a few outcrops between the Killik and (1962a, p. C2) ; Arcticoceras, by Spath (1932, p. 50- Itkillik Rivers in north-central Alaska (Patton and 53), Callomon (1959, p. 508), and Arkell and others Tailleur, 1964, p. 444), and in extensive outcrops (1957, p. L302) ; and Choffatia, by Spath (1931, p. between the Sagavanirktok and Aichilik Rivers in 325), Arkell and others (1957, p. L317), and Arkell northeastern Alaska (Imlay and Detterman, 1973, (1958, p. 211). p. 9, 12). At most places they consist of siltstone, silty shale, and pyritic clay shale that contain iron­ The ammonites Cranocephalites, Arctocephalites, stone concretions and are mostly noncalcareous. In and Arcticoceras represent a biological and strati- the Killik-Itkillik area, however, the beds consist of graphic succession. Cranocephalites is characterized interbedded tuffaceous graywacke, siltstone, clay- by a compressed to stout shell, a very small umbili­ stone, chert, and silty limestone. cus on its septate whorls, a contracted body cham­ ber, a terminal constriction, and high sharp ribbing In northeastern Alaska, the Bathonian
Load more

Recommended publications
  • Or Early Callovian) Ammonites from Alaska and Montana
    Jurassic (Bathonian or Early Callovian) Ammonites From Alaska and Montana By RALPH W. IMLAY SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY GEOLOGICAL SURVEY PROFESSIONAL PAPER 374-C Descr$tions and illustrations of ctphalopods of possible late Middle Jurasric (Bathonian) age UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1962 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 25, D.C. CONTENTS Page Page C- 1 Age of the faunas-Continued C- 1 Callovian versus Bathonian in Greenland- - - - _ - - _ - - C-2 Callovian versus Bathonian in Alaska and Montana- -- - Stratigraphic summary- __ --______ _ - - - -- - ---.- -- -.- - - C-2 Paleogeographic considerations- - -_-- -- ---- ---- Cook Inlet region, Alaska -______--------.-.--..--c-2 Summation of the evidence- - - _._ _ - _ _ - - - - - - - - - - - - Iniskin Peninsula-_-_______----.--------~.--C-2 Comparisons with other faunas---------___----------- Peninsula north of Chinitna Bay----- __._ _ _._ - C-3 \Vestern interior of Canada- - - -- -- -____------- --- Talkeetna Mountains ----___-_ - - -- ---- - - -- - -- C-3 Arctic region-_-_---___-_----------------------- Western Montana- - -----__-----------------.---C-5 other regions--__-__-____----------------------- Rocky Mountain front north of the Sun River- (2-5 Geographic distribution ___-___ --- - ---------- ------ -- - Drummond area--- ---_____ _--- -- -.-- ---- -- - C-10 Summary of results- --_-____-_----_---_-_----------- Age ofthe faunas-----------_----------------------- GI0 Systematic descriptions--_ _ _ - _ - - - - - - - - - - - - - - - - - - - - - - - Evidence from Alaska---____________--------------C-10 Literature cited _-_-_---______----------------------- Evidence from Montana --_-_____ --- - - -- .--- --- - - C-12 Index---__--___-_-_------------------------------- ILLUSTRATIONS [Plates 1-3 follow index] PLATE 1. Holcophylloceras, Oecotraustes (Paroecotraustes) ?, and Arctocephalites (Cranocephalites). 2.
    [Show full text]
  • Post-Carboniferous Stratigraphy, Northeastern Alaska by R
    Post-Carboniferous Stratigraphy, Northeastern Alaska By R. L. DETTERMAN, H. N. REISER, W. P. BROSGE,and]. T. DUTRO,JR. GEOLOGICAL SURVEY PROFESSIONAL PAPER 886 Sedirnentary rocks of Permian to Quaternary age are named, described, and correlated with standard stratigraphic sequences UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON 1975 UNITED STATES DEPARTMENT OF THE INTERIOR ROGERS C. B. MORTON, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director Library of Congress Cataloging in Publication Data Detterman, Robert L. Post-Carboniferous stratigraphy, northeastern Alaska. (Geological Survey Professional Paper 886) Bibliography: p. 45-46. Supt. of Docs. No.: I 19.16:886 1. Geology-Alaska. I. Detterman, Robert L. II. Series: United States. Geological Survey. Professional Paper 886. QE84.N74P67 551.7'6'09798 74-28084 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 Stock Number 024-001-02687-2 CONTENTS Page Page Abstract __ _ _ _ _ __ __ _ _ _ _ _ _ _ _ _ _ _ _ __ __ _ _ _ _ _ _ __ __ _ _ __ __ __ _ _ _ _ __ 1 Stratigraphy__:_Continued Introduction __________ ----------____ ----------------____ __ 1 Kingak Shale ---------------------------------------- 18 Purpose and scope ----------------------~------------- 1 Ignek Formation (abandoned) -------------------------- 20 Geographic setting ------------------------------------ 1 Okpikruak Formation (geographically restricted) ________ 21 Previous work and acknowledgments ------------------ 1 Kongakut Formation ----------------------------------
    [Show full text]
  • The Middle Jurassic of Western and Northern Europe: Its Subdivisions, Geochronology and Correlations
    The Middle Jurassic of western and northern Europe: its subdivisions, geochronology and correlations John H. Callomon The palaeogeographic settings of Denmark and East Greenland during the Middle Jurassic are outlined. They lay in the widespread epicontinental seas that covered much of Europe in the post-Triassic transgression. It was a period of continuing eustatic sea-level rise, with only distant connections to world oceans: to the Pacific, via the narrow Viking Straits between Greenland and Norway and hence the arctic Boreal Sea to the north; and to the subtropical Tethys, via some 1200 km of shelf-seas to the south. The sedimentary history of the region was strongly influenced by two factors: tectonism and climate. Two modes of tectonic movement governed basinal evolution: crustal extension lead- ing to subsidence through rifting, such as in the Viking and Central Grabens of the North Sea; and subcrustal thermal upwelling, leading to domal uplift and the partition of marine basins through emergent physical barriers, as exemplified by the Central North Sea Dome with its associated volcanics. The climatic gradient across the 30º of temperate latitude spanned by the European seas governed biotic diversity and biogeography, finding expression in rock-forming biogenic carbonates that dominate sediments in the south and give way to largely siliciclastic sediments in the north. Geochronology of unrivalled finesse is provided by standard chronostratigraphy based on the biostratigraphy of ammonites. The Middle Jurassic saw the onset of considerable bioprovincial endemisms in these guide-fossils, making it necessary to construct parallel standard zonations for Boreal, Subboreal or NW European and Submediterranean Provinces, of which the NW European zonation provides the primary international standard.
    [Show full text]
  • Lower Jurassic to Lower Middle Jurassic Succession at Kopy Sołtysie and Płaczliwa Skała in the Eastern Tatra Mts (Western
    Volumina Jurassica, 2013, Xi: 19–58 Lower Jurassic to lower Middle Jurassic succession at Kopy Sołtysie and Płaczliwa Skała in the eastern Tatra Mts (Western Carpathians) of Poland and Slovakia: stratigraphy, facies and ammonites Jolanta IWAŃCZUK1, Andrzej IWANOW1, Andrzej WIERZBOWSKI1 Key words: stratigraphy, Lower to Middle Jurassic, ammonites, microfacies, correlations, Tatra Mts, Western Carpathians. Abstract. The Lower Jurassic and the lower part of the Middle Jurassic deposits corresponding to the Sołtysia Marlstone Formation of the Lower Subtatric (Krížna) nappe in the Kopy Sołtysie mountain range of the High Tatra Mts and the Płaczliwa Skała (= Ždziarska Vidla) mountain of the Belianske Tatra Mts in the eastern part of the Tatra Mts in Poland and Slovakia are described. The work concentrates both on their lithological and facies development as well as their ammonite faunal content and their chronostratigraphy. These are basinal de- posits which show the dominant facies of the fleckenkalk-fleckenmergel type and reveal the succession of several palaeontological microfacies types from the spiculite microfacies (Sinemurian–Lower Pliensbachian, but locally also in the Bajocian), up to the radiolarian microfacies (Upper Pliensbachian and Toarcian, Bajocian–Bathonian), and locally the Bositra (filament) microfacies (Bajocian– Bathonian). In addition, there appear intercalations of detrital deposits – both bioclastic limestones and breccias – formed by downslope transport from elevated areas (junction of the Sinemurian and Pliensbachian, Upper Toarcian, and Bajocian). The uppermost Toarcian – lowermost Bajocian interval is represented by marly-shaly deposits with a marked admixture of siliciclastic material. The deposits are correlated with the coeval deposits of the Lower Subtatric nappe of the western part of the Tatra Mts (the Bobrowiec unit), as well as with the autochthonous-parachthonous Hightatric units, but also with those of the Czorsztyn and Niedzica successions of the Pieniny Klippen Belt, in Poland.
    [Show full text]
  • Appendix 3.Pdf
    A Geoconservation perspective on the trace fossil record associated with the end – Ordovician mass extinction and glaciation in the Welsh Basin Item Type Thesis or dissertation Authors Nicholls, Keith H. Citation Nicholls, K. (2019). A Geoconservation perspective on the trace fossil record associated with the end – Ordovician mass extinction and glaciation in the Welsh Basin. (Doctoral dissertation). University of Chester, United Kingdom. Publisher University of Chester Rights Attribution-NonCommercial-NoDerivatives 4.0 International Download date 26/09/2021 02:37:15 Item License http://creativecommons.org/licenses/by-nc-nd/4.0/ Link to Item http://hdl.handle.net/10034/622234 International Chronostratigraphic Chart v2013/01 Erathem / Era System / Period Quaternary Neogene C e n o z o i c Paleogene Cretaceous M e s o z o i c Jurassic M e s o z o i c Jurassic Triassic Permian Carboniferous P a l Devonian e o z o i c P a l Devonian e o z o i c Silurian Ordovician s a n u a F y r Cambrian a n o i t u l o v E s ' i k s w o Ichnogeneric Diversity k p e 0 10 20 30 40 50 60 70 S 1 3 5 7 9 11 13 15 17 19 21 n 23 r e 25 d 27 o 29 M 31 33 35 37 39 T 41 43 i 45 47 m 49 e 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79 81 83 85 87 89 91 93 Number of Ichnogenera (Treatise Part W) Ichnogeneric Diversity 0 10 20 30 40 50 60 70 1 3 5 7 9 11 13 15 17 19 21 n 23 r e 25 d 27 o 29 M 31 33 35 37 39 T 41 43 i 45 47 m 49 e 51 53 55 57 59 61 c i o 63 z 65 o e 67 a l 69 a 71 P 73 75 77 79 81 83 n 85 a i r 87 b 89 m 91 a 93 C Number of Ichnogenera (Treatise Part W)
    [Show full text]
  • Paleontological Resources at Grand Teton National Park, Northwestern Wyoming Vincent L
    University of Wyoming National Park Service Research Center Annual Report Volume 22 22nd Annual Report, 1998 Article 7 1-1-1998 Paleontological Resources at Grand Teton National Park, Northwestern Wyoming Vincent L. Santucci National Park Service William P. Wall Georgia College and State University Follow this and additional works at: http://repository.uwyo.edu/uwnpsrc_reports Recommended Citation Santucci, Vincent L. and Wall, William P. (1998) "Paleontological Resources at Grand Teton National Park, Northwestern Wyoming," University of Wyoming National Park Service Research Center Annual Report: Vol. 22 , Article 7. Available at: http://repository.uwyo.edu/uwnpsrc_reports/vol22/iss1/7 This Grand Teton National Park Report is brought to you for free and open access by Wyoming Scholars Repository. It has been accepted for inclusion in University of Wyoming National Park Service Research Center Annual Report by an authorized editor of Wyoming Scholars Repository. For more information, please contact [email protected]. Santucci and Wall: Paleontological Resources at Grand Teton National Park, Northwest PALEONTOLOGICAL RESOURCES AT GRAND TETON NATIONAL PARK, NORTHWESTERN WYOMING + VINCENT L. SANTUCCI+ NATIONAL PARK SERVICE KEMMERER + WY WILLIAM P. WALL+ DEPARTMENT OF BIOLOGY GEORGIA COLLEGE AND STATE UNIVERSITY MILLEDGEVILLE + GA + ABSTRACT landscape, and though the last great ice masses melted 15 ,000 years ago, some re-established small Paleontological resources occur throughout glaciers still exist. the formations exposed in Grand Teton National Park. A comprehensive paleontological survey has This report provides a preliminary not been attempted previously at Grand Teton assessment of paleontological resources identified at National Park. Preliminary paleontologic resource Grand Teton National Park. data is given in this report in order to establish baseline data.
    [Show full text]
  • Text of Draft
    Reconnaissance bedrock geologic map for the northern Alaska Peninsula area, southwest Alaska Including the Dillingham, Iliamna, Lake Clark, Taylor Mountains and the western part of the Kenai and Seldovia 1:250,000-scale quadrangles Compiled by Frederic H. Wilson, Robert B. Blodgett, Charles D. Blomé, Solmaz Mohadjer, Cindi C. Preller, Edward P. Klimasauskas, Bruce M. Gamble, and Warren L. Coonrad DISCLAIMER This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. This World-Wide-Web publication was prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Although all data and software published on this Web-site have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and (or) the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials.
    [Show full text]
  • Calcareous Nannofossil Zonation and Sequence Stratigraphy of the Jurassic System, Onshore Kuwait
    GeoArabia, 2015, v. 20, no. 4, p. 125-180 Gulf PetroLink, Bahrain Calcareous nannofossil zonation and sequence stratigraphy of the Jurassic System, onshore Kuwait Adi P. Kadar, Thomas De Keyser, Nilotpaul Neog and Khalaf A. Karam (with contributions from Yves-Michel Le Nindre and Roger B. Davies) ABSTRACT This paper presents the calcareous nannofossil zonation of the Middle and Upper Jurassic of onshore Kuwait and formalizes current stratigraphic nomenclature. It also interprets the positions of the Jurassic Arabian Plate maximum flooding surfaces (MFS J10 to J110 of Sharland et al., 2001) and sequence boundaries in Kuwait, and correlates them to those in central Saudi Arabia outcrops. This study integrates data from about 400 core samples from 11 wells representing a nearly complete Middle to Upper Jurassic stratigraphic succession. Forty-two nannofossil species were identified using optical microscope techniques. The assemblage contains Tethyan nannofossil markers, which allow application of the Jurassic Tethyan nannofossil biozones. Six zones and five subzones, ranging in age from Middle Aalenian to Kimmeridgian, are established using first and last occurrence events of diagnostic calcareous nannofossil species. A chronostratigraphy of the studied formations is presented, using the revised formal stratigraphic nomenclature. The Marrat Formation is barren of nannofossils. Based on previous studies it is dated as Late Sinemurian–Early Aalenian and contains Middle Toarcian MFS J10. The overlying Dhruma Formation is Middle or Late Aalenian (Zone NJT 8c) or older, to Late Bajocian (Subzone NJT 10a), and contains Lower Bajocian MFS J20. The overlying Sargelu Formation consists of the Late Bajocian (Subzone NJT 10b) Sargelu-Dhruma Transition, and mostly barren Sargelu Limestone in which we place Lower Bathonian MFS J30 near its base.
    [Show full text]
  • Geological Survey Canada
    BULLETIN 119 GEOLOGICAL SURVEY OF CANADA DEPARTMENT OF MINES AND TECHNICAL SURVEYS THE JURASSIC FAUNAS OF THE CANADIAN ARCTIC CADOCERATINAE Hans Frebold Price $2.50 1964 GEOLOGICAL SURVEY OF CANADA BULLE TIN 119 THE JURASSIC FAUNAS OF THE CANADIAN ARCTIC CADOCERATINAE By Hans Frebold DEPARTMENT OF MINES AND TECHNICAL SURVEYS CANADA © Crown Copyrights reserved Available by mail from the Queen's Printer, Ottawa, from Geological Survey of Canada, 601 Booth St., Ottawa, and at the following Canadian Government bookshops: OTTAWA Daly Building, corner Mackenzie and Rideau TORONTO Mackenzie Building, 36 Adelaide St. East MONTREAL JEterna-Vie Building, 1182 St. Catherine St. West or through your bookseller A deposit copy of this publication is also available for reference in public libraries across Canada Price $2.50 Catalogue No. 42-119 Price subject to change without notice ROGER DUHAMEL, F.R.S.C. Queen's Printer and Controller of Stationery Ottawa, Canada 1964 PREFACE This report is based on fossil collections made over a vast area of the Canadian Arctic extending from Axel Heiberg Island in the north to the Aklavik region of the mainland and is a further contribution by the author on the Jurassic faunas of the Canadian Arctic. Detailed study of these ammonite faunas permits correlation of the associated Jurassic rocks and shows their faunal and stratigraphic relation­ ships with Alaska, East Greenland, and the Arctic areas of Europe and Asia. J. M. HARRISON, Director, Geological Survey of Canada OTTAWA, December 2, 1963 BULLETIN 119 — Die Jurafaunen der kanadischen Acktis CADOCERATINAE. Von Hans Frebold BiojiJieTeHt, 119 — r. <3>pe6ojib,,zT.
    [Show full text]
  • Letter to the Editor
    GeoArabia, Vol. 10, No. 3, 2005 Gulf PetroLink, Bahrain LETTER TO THE EDITOR from Ghaida Al-Sahlan ([email protected]), Kuwait Oil Company, Ahmadi, Kuwait n the recent GeoArabia, Haq and Al-Qahtani (2005) updated the chronostratigraphic Arabian Plate Iframework of Sharland et al. (2001). These studies cite the paper by Yousif and Nouman (1997) to represent the Jurassic type section of Kuwait. Yousif and Nouman published the composite log for the Minagish-27 well (see Figure on page 194) and depicted the Jurassic formations and stages, side-by- side, but only in a generalized manner. In order to refine the ages for this section, I would like to share some preliminary unpublished biostratigraphic and Sr isotope data (see Table and Notes) from analyses by Varol Research (1997 unpublished report), ExxonMobil (1998 unpublished report) and Fugro-Robertson (2004 unpublished report). To convert Sr ages (Ma) to biostages, or biostages to ages, I have used the Geological Time Scale (GTS) 2004 (Gradstein et al., 2004). I thank G.W. Hughes, A. Lomando, M. Miller and O. Varol for their comments. Unit or Boundary Age and Stage Gradstein et al. (2004) Makhul (Offshore) Tithonian-Berriasian (Bio) Base Makhul (N. Kuwait) No younger than Tithonian (Bio) greater than 145.5 + 4.0 Top Hith (W. Kuwait) 150.0 (Sr) = c. Tithonian/Kimmeridgian ? 150.8 + 4.0 Upper Najmah (S. Kuwait) 155.0 (Sr) = c. Kimmeridgian/Oxfordian 155.7 + 4.0 Najmah (N. Kuwait) No older than Oxfordian (Bio) less than 161.2 + 4.0 Lower Najmah Shale (N. Kuwait) middle and late Bathonian (Bio) 166.7 to 164.7 + 4.0 Top Sargelu (S.
    [Show full text]
  • The Late Jurassic Tithonian, a Greenhouse Phase in the Middle Jurassic–Early Cretaceous ‘Cool’ Mode: Evidence from the Cyclic Adriatic Platform, Croatia
    Sedimentology (2007) 54, 317–337 doi: 10.1111/j.1365-3091.2006.00837.x The Late Jurassic Tithonian, a greenhouse phase in the Middle Jurassic–Early Cretaceous ‘cool’ mode: evidence from the cyclic Adriatic Platform, Croatia ANTUN HUSINEC* and J. FRED READ *Croatian Geological Survey, Sachsova 2, HR-10000 Zagreb, Croatia Department of Geosciences, Virginia Tech, 4044 Derring Hall, Blacksburg, VA 24061, USA (E-mail: [email protected]) ABSTRACT Well-exposed Mesozoic sections of the Bahama-like Adriatic Platform along the Dalmatian coast (southern Croatia) reveal the detailed stacking patterns of cyclic facies within the rapidly subsiding Late Jurassic (Tithonian) shallow platform-interior (over 750 m thick, ca 5–6 Myr duration). Facies within parasequences include dasyclad-oncoid mudstone-wackestone-floatstone and skeletal-peloid wackestone-packstone (shallow lagoon), intraclast-peloid packstone and grainstone (shoal), radial-ooid grainstone (hypersaline shallow subtidal/intertidal shoals and ponds), lime mudstone (restricted lagoon), fenestral carbonates and microbial laminites (tidal flat). Parasequences in the overall transgressive Lower Tithonian sections are 1– 4Æ5 m thick, and dominated by subtidal facies, some of which are capped by very shallow-water grainstone-packstone or restricted lime mudstone; laminated tidal caps become common only towards the interior of the platform. Parasequences in the regressive Upper Tithonian are dominated by peritidal facies with distinctive basal oolite units and well-developed laminate caps. Maximum water depths of facies within parasequences (estimated from stratigraphic distance of the facies to the base of the tidal flat units capping parasequences) were generally <4 m, and facies show strongly overlapping depth ranges suggesting facies mosaics. Parasequences were formed by precessional (20 kyr) orbital forcing and form parasequence sets of 100 and 400 kyr eccentricity bundles.
    [Show full text]
  • A Comparison of the Dinosaur Communities from the Middle
    Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 31 July 2018 doi:10.20944/preprints201807.0610.v1 Peer-reviewed version available at Geosciences 2018, 8, 327; doi:10.3390/geosciences8090327 1 Review 2 A comparison of the dinosaur communities from 3 the Middle Jurassic of the Cleveland (Yorkshire) 4 and Hebrides (Skye) basins, based on their ichnites 5 6 Mike Romano 1*, Neil D. L. Clark 2 and Stephen L. Brusatte 3 7 1 Independent Researcher, 14 Green Lane, Dronfield, Sheffield S18 2LZ, England, United Kingdom; 8 [email protected] 9 2 Curator of Palaeontology, The Hunterian, University of Glasgow, University Avenue, Glasgow 10 G12 8QQ, Scotland, United Kingdom; [email protected] 11 3 Chancellor's Fellow in Vertebrate Palaeontology, School of Geosciences, University of Edinburgh, 12 Grant Institute, The King's Buildings, James Hutton Road, Edinburgh EH9 3FE, Scotland, United Kingdom; 13 [email protected] 14 * Correspondence: [email protected]; Tel.: 01246 417330 15 16 Abstract: 17 Despite the Hebrides and Cleveland basins being geographically close, research has not 18 previously been carried out to determine faunal similarities and assess the possibility of links 19 between the dinosaur populations. The palaeogeography of both areas during the Middle Jurassic 20 shows that there were no elevated landmasses being eroded to produce conglomeratic material in 21 the basins at that time. The low-lying landscape and connected shorelines may have provided 22 connectivity between the two dinosaur populations. 23 The dinosaur fauna of the Hebrides and Cleveland basins has been assessed based primarily 24 on the abundant ichnites found in both areas as well as their skeletal remains.
    [Show full text]