Toarcian, Aalenian and Early Bajocian (Jurassic)
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The Jurassic Pleurotomarioidean Gastropod Laevitomaria and Its Palaeobiogeographical History
The Jurassic pleurotomarioidean gastropod Laevitomaria and its palaeobiogeographical history ROBERTO GATTO, STEFANO MONARI, JÁNOS SZABÓ, and MARIA ALESSANDRA CONTI Gatto, R., Monari, S., Szabó, J., and Conti, M.A. 2015. The Jurassic pleurotomarioidean gastropod Laevitomaria and its palaeobiogeographical history. Acta Palaeontologica Polonica 60 (1): 217–233. The genus Laevitomaria is reviewed and its palaeobiogeographical history is reconstructed based on the re-examination of its type species L. problematica, the study of material stored at the National Natural History Museum of Luxembourg, and an extensive review of the literature. The systematic study allows ascribing to Laevitomaria a number of Jurassic species from the western European region formerly included in other pleurotomariid genera. The following new combi- nations are proposed: Laevitomaria allionta, L. amyntas, L. angulba, L. asurai, L. daityai, L. fasciata, L. gyroplata, L. isarensis, L. joannis, L. repeliniana, L. stoddarti, L. subplatyspira, and L. zonata. The genus, which was once considered as endemic of the central part of the western Tethys, shows an evolutionary and palaeogeographical history consider- ably more complex than previously assumed. It first appeared in the Late Sinemurian in the northern belt of the central western Tethys involved in the Neotethyan rifting, where it experienced a first radiation followed by an abrupt decline of diversity in the Toarcian. Species diversity increased again during Toarcian–Aalenian times in the southernmost part of western European shelf and a major radiation occurred during the Middle Aalenian to Early Bajocian in the northern Paris Basin and southern England. After a latest Bajocian collapse of diversity, Laevitomaria disappeared from both the central part of western Tethys and the European shelf. -
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. -
Systematics of the Middle Jurassic Heteromorphic Ammonites
UDC 564. 53 . 01 SYSTEMATICS OF THE MIDDLE JURASSIC HETEROMORPHIC AMMONITES N. V. Besnosov and V. V. Kutuzova All-Union Scientific Research Petroleum Geologic Exploration Institute (VSEGEI) ABSTRACT: The stratigraphic distribution, phylogenetic relationships, and systema tics of the Middle Jurassic heteromorphic ammonites and their relationship to the monomorphic ammonites are considered. Sulcohamitoides gen. nov. and Ga�antiana as a�jani sp. nov. are described. * * * The vast majority of Middle Jurassic heteromorphic ammonites are shells with a spiral developing early in one plane, all the way to the formation of a straight tube in the outer part of the phragmocone and in the living chamber. They are also characterized by reduction of the U and I lobes in ontogenesis, manifested to a greater or lesser degree, and by only slight dissection of their lobes and saddles. The following generic names of the Jurassic heteromorphs are given in the lite rature. A�cuce�as Potonie, 1929, for which the family Arcuceratidae Arkell, 1950 has been proposed. This genus is based on a single species, A. ma�thae Potonie, from the Pliensbachian of Germany, the only specimen of which has been lost. Repeated searches at the type locality have been unsuccessful. It has been suggested that the dating is erroneous, or that the species and genus are based not on a heteromor phic ammonite, but on acrinoid stem. Apso��oce�as Hyatt, 1900, occurs in the lower half of the subfu�catum zone of the Upper-Bajocian and has usually been combined with Spi�oce�as Quenstedt, 1858, from which it differs in its less reduced U and I lobes and its finer sculpture. -
Expanded Jurassic Timescale
TimeScale Creator 2012 chart Russian and Ural regional units Russia Platform regional units Calca Jur-Cret boundary regional Russia Platform East Asian regional units reous stages - British and Boreal Stages (Jur- Australia and New Zealand regional units Marine Macrofossils Nann Standard Chronostratigraphy British regional Boreal regional Cret, Perm- Japan New Zealand Chronostratigraphy Geomagnetic (Mesozoic-Paleozoic) ofossil stages stages Carb & South China (Neogene & Polarity Tethyan Ammonoids s Ma Period Epoch Age/Stage Substage Cambrian) stages Cret) NZ Series NZ Stages Global Reconstructions (R. Blakey) Ryazanian Ryazanian Ryazanian [ no stages M17 CC2 Cretaceous Early Berriasian E Kochian Taitai Um designated ] M18 CC1 145 Berriasella jacobi M19 NJT1 Late M20 7b 146 Lt Portlandian M21 Durangites NJT1 M22 7a 147 Oteke Puaroan Op M22A Micracanthoceras microcanthum NJT1 Penglaizhenian M23 6b 148 Micracanthoceras ponti / Volgian Volgian Middle M24 Burckhardticeras peroni NJT1 Tithonian M24A 6a 149 M24B Semiformiceras fallauxi NJT15 M25 b E 150 M25A Semiformiceras semiforme NJT1 5a Early M26 Semiformiceras darwini 151 lt-Oxf N M-Sequence Hybonoticeras hybonotum 152 Ohauan Ko lt-Oxf R Kimmeridgian Hybonoticeras beckeri 153 m- Lt Late Oxf N Aulacostephanus eudoxus 154 m- NJT14 Late Aspidoceras acanthicum Oxf R Kimmeridgian Kimmeridgian Kimmeridgian Crussoliceras divisum 155 155.431 Card- N Ataxioceras hypselocyclum 156 E Early e-Oxf Sutneria platynota R Idoceras planula Suiningian 157 Cal- Oxf N Epipeltoceras bimammatum 158 lt- Lt Callo -
Palaeoclimatic and Biotic Changes During the Aalenian (Middle ]Urassic) at the Southern Laurasian Seaway (Basque-Cantabrian Basin, Northern Spain)
Palaeoclimatic and biotic changes during the Aalenian (Middle ]urassic) at the southern Laurasian Seaway (Basque-Cantabrian Basin, northern Spain) a,*, L. b, b, b Juan J. Gomez Maria Canales Soled ad Ureta Antonio Goy • Dpto, de Estratigrafia, Facultad de Ciencias Ge%gicas (UCM) and Instituto de Geologfa Econ6mica (CSIC-UCM), 28040 Madrid, Spain b Dpto, de Paleonto[ogia, Facultad de Ciencias Ge%gicas (UCM) and Instituto de Geologia Econ6mica (CSIC-UCM),28040 Madrid, Spain ABSTRACT The uppermost Toarcian-lowermost 8ajocian deposits have been studied in 10 sections located in the western part of the Basque-Cantabrian Basin (northern Spain). The studied 276 successive recorded ammonite assemblages allowed detailed biostratigraphical subdivision and the correlation of the sections at the ammonite zone and subzone scale. The foraminifers were studied in 96 samples and 55 diagenetically screened belemnite rostra were analyzed for C and 0 isotope. Keywords: Facies and thickness distribution of the Aalenian sediments suggest that deposition took place in a nearly Palaeoc1imate symmetrical sub-basin included into an intra plate shallow platform, developed over continental crust, on Biotic changes Foraminifers which flexure was the main control responsible for subsidence and basin evolution. Ammonoids Noteworthy negative 613Cb�1 excursions, coinciding with seawater temperature changes, were recorded Stable isotopes during the Bradfordensis Biochron, around the Concavum-Limitatum biochron boundary, and around the Paiaeoceanography Aalenian-Bajocian boundary. A close relationship between the changes in seawater temperature and the biotic changes observed in the foraminiferal and in the ammonoids assemblages has been evidenced. During the Comptum Biochron, the 6180�1-based palaeotemperature shows a remarkable cooling interval with an average seawater temperature of 15.7 QC. -
Lzlp Herela Imla Y, New Genus, in the United States
The Mesozoic Pelecypods Otc/pirilz Marwick and Lzlp herela Imlay, New Genus, in the United States By RALPH W. IMLAY CONTRIBUTIONS TO PALEONTOLOGY GEOLOGICAL SURVEY PROFESSIONAL PAPER 573-B - -- -- -- UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1967 UNITED STATES DEPARTMENT OF THE INTERIOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY William T. Pecora, Director For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price 25 cents (paper cover) CONTENTS Page Page Abstract --------- ------------ ---- --- - - --- - - ---- --- - B1 Biological relationships- - _ _ __------ --- -- - - - ---- --- -- B2 Introduction- -----------------..-------------------- 1 Comparisons of species -________-_------------------- 3 Characteristics of Otapiria- _------------.. - --- --- - --- - 1 Systematic descriptions _-_-___ --- - - --- ---- ---- ---- - 3 Characteristics of Lupherella Imlay, n. gen 2 Literature cited __-_._________-----------10 ILLUSTRATIONS [Plates follow "Literature Cited"] PLATE 1. Otapiria. 2. Lupherella, n. gen., and Otapiria. Page FIGURE1. Index map showing occurrences of the pelecypod Otapiria in Alaska .________---_--------A-- ---------------- B7 2. Index map showing occurrences of Lupherella boechiformis (Hyatt) in Oregon and California- - - ._ _ _ _ _ - _ _ _ - - - _ _ 9 TABLES .. Page TABLE 1. Distribution of Otapzrza in space and time- -_----____-_- _-----.. ---- - _-_.._--- -- - --- - - ---- -- - - ---..------. - - B2 2. Comparisons of Triassic and Jurassic species of Otapiria ___--__-__---__-_-_----______-_-------------------4 3. Comparisons of measurements of some Jurassic species of Otapiria and Lupherella __.______-------------------5 111 CONTRIBUTIONS TO PALEONTOLOGY THE MESOZOIC PELECYPODS OTAPIRIA MARWICK AND LUPHERELLA IMLAY, NEW GENUS IN THE UNITED STATES ABSTRArn to determine khe generic and family relationships of The pelecypod genera Otapiria Marwick and Lupherella Lupherelh made the writer familiar with the character- Imlay, n. -
Földtani Közlöny
Földtani Közlöny A MAGYARHONI FÖLDTANI TÁRSULAT FOLYÓIRATA БЮЛЛЕТЕНЬ ВЕНГЕРСКОГО ГЕОЛОГИЧЕСКОГО ОБЩЕСТВА BULLETIN DE LA SOCIÉTÉ GÉOLOGIQUE DE HONGRIE ZEITSCHRIFT DER UNGARISCHEN GEOLOGISCHEN GESELLSCHAFT BULLETIN OF THE HUNGARIAN GEOLOGICAL SOCIETY T. 105. No. 2. (1975) FÖLDTANI KÖZLÖNY A MAGYARHONI FÖLDTANI TÁRSULAT FOLYÓIRATA 105. KÖTET TARTALOMJEGYZÉK - СОДЕРЖАНИЕ - CONTENU ÉRTEKEZÉSEK — НАУЧНЫЕ СТАТЬИ - MEMOIRES DE. STEGENA L.—DE. GÉCZY В.—HORVÁTH F.: A Pannon-medence késő-kainozóos fejlődése — Evolution néogénique récente du Bassin pannonique 101—123 DR. GÉCZY В.: A magyar őslénytan időszerű problémái 124—128 KOVÁTS L.—DR. NAGY L.: Ujabb észlelések a szilikogén porok DTA vizsgálatában 129—142 NÉMETH MÁRTA: Ujabb mészalgák a Bükk-hegységi középsőkarbonból — Neuere Kalkalgen aus dem Mittel karbon des Bükk-Gebirges in Nordungarn 143—154 DR. SIDO MÁRIA: A tatai formáció Foraminiferái (felsőapti) — The Foraminifera of Tata Formation (Upper Aptian) 155—187 DR. В ALDI T. — BÁLDINÉ ВЕКЕ MÁRIA—HORVÁTH MÁRIA—NAGYMAROSI A. —BALOGH K. — SÓS EDIT: Adatok a magyarországi kiscelli agyag abszolút és relatív korához — On the Radiometric Age and the Biostratigraphic Position of the Kiscell Clay in Hungary 188—192 SINGH А. К.: A talajgeokémiai vizsgálatok, mint alkalmazható geokémiai kutató-módszer a rózsabányai területen — Soil analysis as a method of geochemical prospecting in Nagybörzsöny ore deposit, Hungary 193—207 GALÁCZ A.: Bajóci szelvények az Északi Bakonyból — Coupes bajociennes dans le Bakony Septentrional 208—219 DR. T. KOVÁCS G.: A Duna—Tisza köze déli részének miocén képződményei — Das Miozän im Südteil des Donau—Theiss-Zwischenstromlandes 220—236 HÍREK, ISMERTETÉSEK — СООБЩЕНИЯ, РЕЦЕНЗИИ — NOTICES, REVUE BIBLIOGRA PHIQUE 237—247 TÁRSULATI ÜGYEK — ДЕЛА ОБЩЕСТВА - AFFAIRES DE LA SOCIÉTÉ 248-255 ÉRTEKEZÉSEK Földtani Közlöny, Bull, of the Hungarian Oeol. -
Mesozoic and Cenozoic Sequence Stratigraphy of European Basins
Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3789969/9781565760936_frontmatter.pdf by guest on 26 September 2021 Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3789969/9781565760936_frontmatter.pdf by guest on 26 September 2021 MESOZOIC AND CENOZOIC SEQUENCE STRATIGRAPHY OF EUROPEAN BASINS PREFACE Concepts of seismic and sequence stratigraphy as outlined in To further stress the importance of well-calibrated chronos- publications since 1977 made a substantial impact on sedimen- tratigraphic frameworks for the stratigraphic positioning of geo- tary geology. The notion that changes in relative sea level shape logic events such as depositional sequence boundaries in a va- sediment in predictable packages across the planet was intui- riety of depositional settings in a large number of basins, the tively attractive to many sedimentologists and stratigraphers. project sponsored a biostratigraphic calibration effort directed The initial stratigraphic record of Mesozoic and Cenozoic dep- at all biostratigraphic disciplines willing to participate. The re- ositional sequences, laid down in response to changes in relative sults of this biostratigraphic calibration effort are summarized sea level, published in Science in 1987 was greeted with great, on eight charts included in this volume. albeit mixed, interest. The concept of sequence stratigraphy re- This volume also addresses the question of cyclicity as a ceived much acclaim whereas the chronostratigraphic record of function of the interaction between tectonics, eustasy, sediment Mesozoic and Cenozoic sequences suffered from a perceived supply and depositional setting. An attempt was made to estab- absence of biostratigraphic and outcrop documentation. The lish a hierarchy of higher order eustatic cycles superimposed Mesozoic and Cenozoic Sequence Stratigraphy of European on lower-order tectono-eustatic cycles. -
Front Matter (PDF)
THE QUARTERLY JOURNAL OF THE GEOLOGICAL SOCIETY OF LONDON Quod si cui mortalium cordi et cur~e sit, non tantum inventis h~erere atque iis uti, sed ad ulteriora penetrare ; atque non disputando adversarium, sed opere naturam vincere ; denique non belle et probabiliter opinari, sed certo et ostensive scire; tales, tanquam veri scientiarum filii, nobis (si videbitur) se adjungant ; ut omissis natur~e atriis, qu~e infiniti contriverunt, aditus aliquando ad interiora patefiat.--Novum Organum, Prefatio. VOLUME XCV FOR I939 LONDON : LONGMANS, GREEN & CO. LTD. PARIS : CHARLES KLINCKSIECK~ I I RUE DE LILLE. SOLD ALSO AT THE APARTMENTS OF THE SOCIETY~ BURLINGTON HOUSE~ W.I, I94O GEOLOGICAL SOCIETY OF LONDON LIST OF THE OFFICERS AND COUNCIL Elected February 17th, 1939 PRESIDENT Prof. Henry Hurd Swinnerton, D.Sc. VIcE-PRESIDENTS Edward Battersby Bailey, M.C.M.A. Prof. Owen Thomas Jones, M.A.D.Se. D.Sc. F.R.S. F.R.S. Prof. William George Fearnsides, M.A. Prof. Cecil Edgar Tilley, Ph.D.B.Se. F.R.S. F.R.S. S ECR~.TARIES Leonard Hawkes, D.Sc. } Prof. William Bernard Robinson King, I O.B.E, M.A. Sc.D. FOREIGN SECRETARY Sir Arthur Smith Woodward, LL.D.F.R.S.F.L.S. TR]iASURHR Frederick Noel Ashcroft, M.A.F.C.S. COUNCIL William Joseelyn Arkell, M.A.D.Sc. Prof. Owen Thomas Jones, M.A.D.Se. D.Phil. F.R.S. Frederick Noel Ashcroft, M.A.F.C.S. Prof. William Bernard Robinson King, Edward Battersby Bailey, M.C.M.A. O.B.E.M.A. -
Early Bajocian Type Sonniniids and Hammatoceratids SW Germany
Boletín del Instituto de Fisiografía y Geología 91, 2021 1 New information on the Early Bajocian types of sonniniids and hammatoceratids (Ammonitina) described by W. Waagen (1867) from Gingen/Fils (SW Germany) Driss Sadki & Volker Dietze Sadki D. & Dietze V., 2021. New information on the Early Bajocian types of sonniniids and hammatoceratids (Ammonitina) described by W. Waagen (1867) from Gingen/Fils (SW Germany). Boletín del Instituto de Fisiografía y Geología 91: 1-16. Rosario, 08/05/2021. ISSN 1666-115X. Abstract. The type specimens of the species of sonniniids and hammatoceratids (Ammonitina) from the Lower Bajocian of Gingen/Fils (SW Germany) described by Waagen in 1867, and deposited in the Bavarian State Collection for Palaeontology and Geology in Munich, are revised. They are referred to the morphogenera Euhoploceras, Shirbuirnia, Papilliceras, Sonninia, Witchellia, and Fissilobiceras: E. adicrum (Waagen, 1867), E. polyacanthum (Waagen, 1867), E. mayeri (Waagen, 1867), S. gingensis (Waagen, 1867), P. mesacanthum (Waagen, 1867), S. patella (Waagen, 1867), W. jugifera (Waagen, 1867), and F. fissilobatum (Waagen, 1867). A lectotype is designated for E. Recibido 17/09/2020 Aceptado 29/10/2020 mayeri (Waagen, 1867). Keywords: Sonniniidae ▪ Hammatoceratidae ▪ Ammonitina ▪ Middle Jurassic ▪ Lower Bajocian ▪ W. Waagen ▪ Disponible vía Internet Southwest Germany. & versión impresa 08/05/2021 Resumen. Nueva información sobre los tipos de sonníniidos y hammatocerátidos (Ammonitina, Cephalopoda) del Editor: H. Parent Bajociano Inferior de Gingen/Fils (SO de Alemania) descriptos por W. Waagen (1867). Los especímenes tipo de sonníniidos y hammatocerátidos (Ammonitina) del Bajociano Inferior de Gingen/Fils (SO de Alemania) descriptos por Waagen en 1867, actualmente depositados en el Bayerischen Staatssammlung für Paläontologie und Geologie in München, son revisados y referidos a los morfogéneros Euhoploceras, Shirbuirnia, Papilliceras, Sonninia, Witchellia, y Fissilobiceras: E. -
Upper Jurassic Mollusks from Eastern Oregon and Western Idaho
Upper Jurassic Mollusks from Eastern Oregon and Western Idaho GEOLOGICAL SURVEY PROFESSIONAL PAPER 483-D Upper Jurassic Mollusks from Eastern Oregon and Western Idaho By RALPH W. IMLAY CONTRIBUTIONS TO PALEONTOLOGY GEOLOGICAL SURVEY PROFESSIONAL PAPER 483-D Faunal evidence for the presence of Upper Jurassic sedimentary rocks in eastern Oregon and westernmost Idaho UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1964 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 CONTENTS Page Abstract.__________________________________________ Dl Ages and correlations Continued Introduction.______________________________________ 1 Trowbridge Formation of Lupher, 1941, in east- Biologic analysis..._________________________________ 2 central Oregon.__________---_-_-__-_-____---_ D9 Stratigraphic summary._____________________________ 2 Lonesome Formation of Lupher, 1941, in east-central Northeastern Oregon and adjoining Idaho. ________ 2 Oregon..________________-_--_____--_--_---__ 9 Mineral area, western Idaho.____________________ 2 Comparisons with other faunas.______________________ 10 East-central Oregon_____________________________ 4 Alaska and western British Columbia-____________ 10 Conditions of deposition.____________________________ 6 Calif ornia. ... _ __-_________--____-___-__---___-_ 10 Ages and correlations______________________________ 6 Unnamed beds in northeastern Oregon and adjoining Western interior of North America._______________ 10 Idaho_______________________________________ Geographic distribution________-_-_____---_---_-.__ 11 Unnamed beds near Mineral, Idaho.______________ Systematic descriptions..._--_--__-__________________ 13 Snowshoe Formation of Lupher, 1941, in east-central Literature cited_____-__-_____---------_-_--_--__-___ 17 Oregon._____________________________________ Index_.______________--____---------_-__---_-_-___ 21 ILLUSTRATIONS [Plates 1-4 follow index] PLATE 1. -
The Graphoceratid Ammonite Succession in the Aalenian and Lowest Bajocian (Middle Jurassic) at Horn Park, Dorset, UK ROBERT B
The Graphoceratid Ammonite Succession in the Aalenian and lowest Bajocian (Middle Jurassic) at Horn Park, Dorset, UK ROBERT B. CHANDLER Riddlesdown High School, Purley, Surrey, CR8 lEX Summary In 1990 Callomon and Chandler set out a scheme of 16 faunal horizons for the Aalenian-Lower Bajocian of Dorset and Somerset based principally on graphoceratid ammonites. One locality, Horn Park, stands apart in displaying strata from almost all the horizons identified in that work. Yet little material from it has ever been figured. Here a section is given together with exhaustive tables of existing nominal morphospecies collected at each level and with figures that allow the variability of the suc- cessive, probably in most cases, monobiospecific assemblages to be assessed. A revised generic classification of the Graphoceratidae is presented. them precludes almost any satisfactory discussion of phyletic relationships and hence of the overall evolution The highly discontinuous, condensed and rapidly of the group. varying development of the Inferior Oolite in southern England was first perceived by S.S. Buckman (e.g. 1891, The biostratigraphy of the Graphoceratidae has now 1893, 1910) during his attempts to correlate sections by been rather well documented, for example by Rocha et means of ammonites. Leading amongst these in al. (1990), Henriques (1992; et al. 1994) in Portugal; the Aalenian part of the succession are the Linares and Sandoval (1990) in Spain, Sadki (1994) in Graphoceratidae, including such well known genera as Morocco. In Britain, Morton (1990; 1994) and Morton Leioceras, Ludwigia, Brasilia, Graphoceras and and Hudson (1995) have described the succession in Hyperlioceras. Scotland and compared it with Dorset (Morton and Chandler 1994).