Results 31 to 40 of about 2,944 (200)
When second language (L2) learners speak in their L2, they can make errors involving one or several distinct linguistic levels (e.g., pronunciation errors, wrong lexical and morphosyntactic choices).
Sylvain Detey +2 more
doaj +1 more source
The composition of intrusive rocks suggests that the magma was likely generated in a subduction‐related setting. The arc crustal thickness in the Phnom Sro Ngam and Halo Prospects was probably < 40 km during emplacement. Zircon U–Pb age range indicates a correlation with Loei Fold Belt magmatic activity.
Sirisokha Seang +6 more
wiley +1 more source
Temporal and Hf isotope geochemical evolution of southern Finnish Lapland from 2.77 Ga to 1.76 Ga [PDF]
The southern Finnish Lapland area in the central part of the Fennoscandian shield is a geologically complex zone comprising several Archean blocks and Paleoproterozoic supracrustal belts all of which are intruded by voluminous Paleoproterozoic granites ...
L.S. Lauri +3 more
doaj +1 more source
Early zircon saturation and crystallisation occur in mafic (52–54 wt.% SiO2) lavas at Tengchong volcanic field. These early formed zircons with high δ18O (6.6‰–7.9‰) indicates mantle enrichment by subducted supracrustal materials. ABSTRACT Late Pleistocene (< 0.2 Ma) mafic and evolved volcanic rocks occur in northern Tengchong Volcanic Field, SE ...
Lizhu Wang, Haibo Zou
wiley +1 more source
Our petrochemical studies on ~1.2 Ga granitoids of the Natal Metamorphic Belt, South Africa, do not suggest any property similar to Phanerozoic‐style subduction‐related granitoids. Plot of Kotongweni Tonalite in Y versus Sr diagram (after Moyen 2011), note that most samples have Sr/Y < 50.
Palesa Leuta +2 more
wiley +1 more source
Gravitational Potential Energy per Unit Area as a Constraint on Archean Sea Level
To constrain the density structure of Archean lithosphere, I assume that gravitational potential energy (GPE) per unit area at Archean spreading centers equals that for continents whose surfaces lay near sea level.
Peter Molnar
doaj +1 more source
Petrography, thermobarometry, and pseudosection modelling reveal peak metamorphic conditions of 3–7.5 kbar and 520°C–800°C in Tonian‐Cryogenian orthogneisses of the Dom Feliciano Belt. Metamorphic field gradients of 27°C/km–39°C/km and variable exhumation mechanisms support correlation of these units as remnants of a Himalayan‐type Piratini Orogeny ...
Thaiane Niederauer‐Santos +6 more
wiley +1 more source
"Clifford's Rule" and the geodynamics of kimberlite magmatism
The Clifford rule emphasizes the association of kimberlite magmatism with the crust areas of Archean and Early Proterozoic age. Though there are diamantiferous and highly productive primary diamond deposits outside Archean cratons, the Clifford rule is ...
O. V. Aryasova, Ya. M. Khazan
doaj +1 more source
ABSTRACT Riverine and valley systems across the globe have been central to the development of past urban centres. By AD 900, the Shashe and Limpopo Rivers seem to have facilitated the interaction and integration of early farming communities in southern Africa. This paper focuses on the application of geoarchaeological perspectives made available by the
B. S. Nxumalo
wiley +1 more source
ABSTRACT Reconstructing the pressure–temperature–time (P–T–t) evolution of (ultra)high‐pressure rocks is essential for constraining subduction and collisional dynamics. Subduction zones are often investigated using basic eclogites, whereas nonbasic high‐pressure rocks remain comparatively understudied, potentially hindering a comprehensive ...
Otavio S. G. Silva +7 more
wiley +1 more source

