Results 121 to 130 of about 92,675 (274)

Internal framework and geochemistry of the Carboniferous Huaco granite pluton, Sierra de Velasco, NW Argentina [PDF]

open access: yes, 2018
The A-type Huaco granite pluton of the Velasco range (Sierras Pampeanas of northwest Argentina) is formed by three coeval granitic facies and contains subordinate coeval-to-late facies, as well as enclaves, dikes and stocks that show different temporal ...
Grosse, Pablo   +3 more
core   +2 more sources

Late Ordovician palaeogeography and the positions of the Kazakh terranes through analysis of their brachiopod faunas

open access: yes, 2017
Detailed biogeographical and biofacies analyses of the Late Ordovician brachiopod faunas with 160 genera, grouped into 94 faunas from individual lithotectonic units within the Kazakh Orogen strongly support an archipelago model for that time in that area.
L. Popov, R. Cocks
semanticscholar   +1 more source

Iberian Ordovician and its international correlation

open access: yesStratigraphy, 2016
The regional chronostratigraphy of the British Ordovician, established mainly for shelly facies, is hard to correlate in the Iberian Peninsula, especially after the separation and drift of Avalonia from Gondwana by the early Middle Ordovician.
J. C. Gutiérrez-Marco   +10 more
semanticscholar   +1 more source

Dynamics of clade diversification on the morphological hypercube

open access: yes, 1998
Understanding the relationship between taxonomic and morphological changes is important in identifying the reasons for accelerated morphological diversification early in the history of animal phyla.
Erwin D. H.   +3 more
core   +3 more sources

Ordovician magmatism in the Pyrenees

open access: yes, 2017
Successive Ordovician magmatic pulsations are well documented in the pre-Variscan basement of the Pyrenees. According to radiometric data, magmatism lasted about 30 m.y., from ca. 477 to 446 Ma, and although the magmatic activity seems to be continuous, two peaks can be distinguished at 473-472 Ma and 457 Ma.
Casas, Josep Maria   +4 more
openaire   +1 more source

An Improved Chemical Extraction Procedure for the Sr Isotope Analysis of Liquid Agrifood Samples Applied to Authenticating the Origin of Maple Syrups in Quebec (Canada)

open access: yesRapid Communications in Mass Spectrometry, Volume 39, Issue 16, 30 August 2025.
ABSTRACT Rationale We describe a new simplified sample preparation technique, based on dual chromatography for the analysis of 87Sr/86Sr in liquid agri‐food samples. We applied this approach for authenticating the origin of maple syrup products in Quebec, characterizing the 87Sr/86Sr of soil profiles from geologically distinct maple groves, including ...
B. Saar de Almeida   +4 more
wiley   +1 more source

A mineral reconnaissance survey of the Abington-Biggar-Moffat-area, south-central Scotland [PDF]

open access: yes, 1979
Panned heavy mineral concentrates, mostly obtained from stream sediments, were collected from 195 sites in the Abington-Biggar-Moffat area. The project area, which lies immediately east of the formerly important mining district of Wanlockhead ...
Dawson, J., Floyd, J.D., Phillip, P.R.
core  

The oldest described eurypterid: a giant Middle Ordovician (Darriwilian) megalograptid from the Winneshiek Lagerstätte of Iowa

open access: yesBMC Evolutionary Biology, 2015
Eurypterids are a diverse group of chelicerates known from ~250 species with a sparse Ordovician record currently comprising 11 species; the oldest fully documented example is from the Sandbian of Avalonia.
J. Lamsdell   +4 more
semanticscholar   +1 more source

The Distribution of Major and Trace Elements Across a Garnet Population From the Kalak Nappe Complex (Finnmark, Scandinavian Caledonides): Evidence for Size‐Dependent Growth and Compositional Equilibration in the Garnet Zone

open access: yesJournal of Metamorphic Geology, Volume 43, Issue 6, Page 613-640, August 2025.
ABSTRACT A garnet population from the lower Kalak Nappe Complex in Finnmark (Arctic Norway) was characterized using high‐resolution X‐ray micro‐computed tomography, electron probe micro‐analysis and laser ablation inductively coupled plasma mass spectrometry mapping to assess the extent of compositional equilibration and the controlling crystallization
M. T. A. G. Yogi   +3 more
wiley   +1 more source

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