Results 71 to 80 of about 16,387 (257)

The Ammonite Siphuncle [PDF]

open access: yesGeological 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

The Douvilleiceratidae (Ammonoidea) of the Lower Aptian historical stratotype area at Cassis-La Bédoule (SE France)

open access: yesCarnets de Géologie, 2008
Recent biostratigraphic research in the marly limestones of the Cassis-La Bédoule area (SE France) provided a rich macrofauna of Douvilleiceratidae Parona & Bonarelli, 1897. From the uppermost Barremian (Pseudocrioceras waagenoides Subzone) to the middle
Tronchetti Guy   +4 more
doaj  

Darwin's Geological Research in Argentina [PDF]

open access: yes, 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
core  

Biostratigraphy of the Cretaceous deposits based on ammonites in the southwest of Qayen area (Qumenjan section)

open access: green, 2021
سید ناصر رئیس السادات   +3 more
openalex   +2 more sources

Biostratigrafie spodní křídy manínské jednotky (lom Butkov, Strážovské vrchy, Západní Karpaty) [PDF]

open access: yes, 2003
This paper is a continuation of systematic stratigraphical research of Lower Cretaceous sequence of the Manín Unit excavated in the Butkov quarry. Calcareous deposits are significant especially by richness of ammonites.
Halásová, Eva   +3 more
core   +1 more source

Ammonites from lumpy limestones (Lower Pliensbachian, Portugal). Taphonomic analysis and palaeoenvironmental implications. [PDF]

open access: yes, 2000
Preservational features of ammonites recorded in the Lower Pliensbachian lumpy limestones of the Lusitanian Basin confirm the deep marine origin previously established for this facies.
Duarte, Luís Vitor   +2 more
core  

Graysonites (Cretaceous Ammonites) from Kyushu With Notes on Stratigraphy [PDF]

open access: bronze, 1960
Tatsuro Matsumoto   +3 more
openalex   +1 more source

Macrofossil extinction patterns at Bay of Biscay Cretaceous-Tertiary boundary sections [PDF]

open access: yes
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.
core   +1 more source

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