Results 81 to 90 of about 12,862 (208)
Geological Magazine, 1920 It is well known that the chambers of Cephalopod shells are connected by an organ called the siphuncle, which passes through the septa by the septal necks. Many investigators who have studied these shells have made careful observations on the siphuncle, hoping thereby to throw light on its functions.
openaire +2 more sources
High-precision U-Pb ages in the early Tithonian to early Berriasian and implications for the numerical age of the Jurassic-Cretaceous boundary [PDF]
, 2019 The numerical age of the Jurassic-Cretaceous boundary has been controversial and difficult to determine. In this study, we present high-precision U-Pb geochronological data around the Jurassic-Cretaceous boundary in two distinct sections from different ...
Aguirre-Urreta, Maria Beatriz +10 more
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Environmental controls on the distribution of neoselachian sharks and rays within the British Bathonian (Middle Jurassic). [PDF]
, 2003 Extensive sampling from a range of facies within the Bathonian (Middle Jurassic) of southern England has allowed the palaeoenvironmental distribution of a number of taxa of neoselachian sharks and rays to be assessed.
Underwood, Charlie J.
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Darwin's Geological Research in Argentina [PDF]
, 2009 On the occasion of the 200th. anniversary of Charles Darwin´s birth, the Asociación Geológica Argentina decided to prepare a special issue devoted to the geological research undertaken by Darwin in Argentina.
Aguirre-Urreta, Maria Beatriz +2 more
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Carnets de Géologie, 2007 Généralement considéré comme une période chaude, le Crétacé supérieur témoigne d'une extension maximale des domaines marins. Les optima transgressifs du Cénomanien et du Turonien inférieur induisent la création de nouveaux domaines de mer épicontinentale
Courville Philippe
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Macrofossil extinction patterns at Bay of Biscay Cretaceous-Tertiary boundary sections [PDF]
Researchers examined several K-T boundary cores at Deep Sea Drilling Project (DSDP) core repositories to document biostratigraphic ranges of inoceramid shell fragments and prisms.
Macleod, Kenneth, Ward, Peter D.
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About the stratigraphic position of the Lower Aptian Roloboceras hambrovi (Ammonoidea) level
Carnets de Géologie, 2008 In the stratotype of the Lower Aptian substage the position of the assemblage that includes Roloboceras spp. and Megatyloceras spp. has been clearly established as being in the middle part of the upper Bedoulian. Some authors have erected this horizon as
Conte Gabriel +3 more
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Carnets de Géologie, 2010 The study of more than 40 sections in the "Creniceras renggeri marls" of the French Jura Range (Lower Oxfordian) has found: * a precise biochronostratigraphic subdivison of 16 successive populations or associations which appears to be stable over the ...
Jardat Rémi
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The History of the Aptian Stage Stratigraphy and Ammonoids of the Central Part of the Northern Caucasus Studies. Paper 1. 19th Century to 1969 [PDF]
Известия Саратовского университета. Новая серия: Серия Науки о ЗемлеThe offering paper covers the history of the Aptian stage stratigraphy and ammonites studies of the central part of the Northern Caucasus, which was subdivided by the author into five stages. The first (mid-to-late 19th century), second (1901–1951)
Polkovoi, Kirill Sergeevich
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Fossils: Digging Into the Past
, 2017 Fossils collected in Renaissance collection cabinets were items of wonder and curiosity. Although sometimes mistaken for other pieces of naturalia, they were widely collected by owners of princely cabinets and scholarly collections.Though naturalists and
Caccioppoli, Sidney N.
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