Results 81 to 90 of about 27,665 (229)

The first report of South American edrioasteroids and the paleoecology and ontogeny of rhenopyrgid echinoderms [PDF]

open access: yes, 2013
A new species of rhenopyrgid edrioasteroid Rhenopyrgus piojoensis sp. nov. is described form the Silurian (Lower Lud− low) Los Espejos Formation in the Precordillera of Argentina.
Heredia, Susana Emma   +3 more
core   +1 more source

The concealed Caledonide basement of eastern England and the southern North Sea : a review [PDF]

open access: yes, 1995
Field mapping, analysis of borehole core and studies of geophysical potential field and seismic data can be used to demonstrate the existence of a number of distinct crustal blocks within Eastern Avalonia beneath eastern England and the southern North ...
England, R., Lee, Mick, Pharaoh, Tim
core   +1 more source

Ostracods and lithofacies of the Middle/Upper Devonian boundary stratotype (Puech de la Suque, Montagne Noire, France)

open access: yesBulletin de la Société Géologique de France, 2007
Abstract This paper discusses ostracods and their environmental setting close to the Givetian/Frasnian boundary in the Puech de la Suque Global Stratotype Section and Point. The ostracod fauna belongs exclusively to the Eifelian mega-assemblage and is largely dominated by Podocopina instars.
Casier, Jean-Georges, Préat, Alain
openaire   +1 more source

Early evolutionary history of the seed

open access: yesBiological Reviews, Volume 101, Issue 3, Page 1511-1553, June 2026.
ABSTRACT The seed is an essential stage in the life history of gymnospermous and angiospermous plants, facilitating both their survival and dispersal. We reappraise knowledge of the evolutionary history of the gymnospermous seed, from its origin in the late Devonian through to the well‐known end‐Permian extinctions – an interval encompassing the ...
Richard M. Bateman   +2 more
wiley   +1 more source

Specific features of carbon and oxygen stable isotopes (δ13C and δ18O) geochemistry in the isolated carbonate platform section on the east of the Urals (the Famennian and Tournaisian Stages)

open access: yesЛитосфера, 2016
New data about the stable carbon and oxygen isotopic composition for the Frasnian/Famennian and Devonian/Carboniferous boundary intervals, as well as for middle and upper parts of the Tournasian Stage (the Lower Carboniferous), are represented in this ...
G. A. Mizens   +4 more
doaj   +2 more sources

UPPER DEVONIAN CONODONT BIOSTRATIGRAPHY OF SHAMS ABAD SECTION, KERMAN PROVINCE, IRAN

open access: yesRivista Italiana di Paleontologia e Stratigrafia, 2011
The study of the conodont fauna from the Upper Devonian Shams Abad section provides new data on the stratigraphy of the Bahram Formation in the Kerman province, in southeastern Iran.
ALI BAHRAMI   +3 more
doaj   +1 more source

Variscan sourcing of Westphalian (Pennsylvanian) sandstones in the Canobie Coalfield, UK [PDF]

open access: yes, 2010
The zircon age spectrum in a sample from the Canonbie Bridge Sandstone Formation (Asturian) of southern Scotland contains two main peaks. One is Early Carboniferous in age (348– 318 Ma), and corresponds to the age of igneous activity during the ...
ANDREW MORTON   +21 more
core   +1 more source

Origins of the Pangkaimen Au Deposit in the Northern Great Xing'an Range, China: Evidence From Geochronological, Geochemical, Fluid Inclusion, and H–O–S–Pb Isotope Data

open access: yesGeological Journal, Volume 61, Issue 5, Page 1291-1309, May 2026.
The Pangkaimen Au–Ag deposits belong to the epithermal Au deposits, which are of great significance for guiding the research and development of this type of gold deposit. Metallogenic model diagram of Pangkaimen Au–Ag deposit. ABSTRACT The gold (Au) metallogenic belt in the northern Great Xing'an Range is characterised by the wide occurrence of the ...
Sheng Lu   +8 more
wiley   +1 more source

Neoproterozoic(?) to Pennsylvanian inner-shelf, miogeoclinal strata in Sierra Agua Verde, Sonora, Mexico

open access: yesRevista Mexicana de Ciencias Geológicas, 2018
Sierra Agua Verde contains one of the most complete and best exposed sections known of inner-shelf miogeoclinal strata in Sonora, Mexico. Over 3,700 m of Neoproterozoic(?), Cambrian, Lower Ordovician, Upper Devonian, Mississippian, and Lower and Middle ...
John H. Stewart   +6 more
doaj  

Couvinian [PDF]

open access: yes, 2006
In the major part of the Dinant Synclinorium, the Couvinian is characterized by a mixed siliciclasticcarbonate sequence, about 750 m thick in the Couvin area.
Bultynck, P.
core  

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