Results 41 to 50 of about 16,900 (220)

Neoarchean Arc Magmatism and Crust Recycling in the Northern Marginal Zone of the Limpopo Complex, Zimbabwe: New Insights From Zircon U‐Pb‐Hf Isotopes of a Charnockite Suite

Geological Journal, EarlyView.
Charnockites with 2691–2607 Ma magmatic ages from the NMZ show arc‐magmatic geochemical signatures. They correspond to the lower‐crustal equivalent of the Chilimanzi Suite Granite in the Zimbabwe Craton. Lu‐Hf isotopic data of magmatic zircons show negative εHf(t) values (−11.18 to −2.20) with TDMC ages of 3699–3158 Ma, suggesting their protolith ...
Toshiaki Tsunogae, Md. Sazzadur Rahman, Gao Pin, M. Santosh, Wataru Fujisaki, Sam Uthup, Prince Mandingaisa   +6 more
wiley   +1 more source

Tertiary-Quaternary subduction processes and related magmatism in the Alpine-Mediterranean region [PDF]

, 2006
During Tertiary to Quaternary times, convergence between Eurasia and Africa resulted in a variety of collisional orogens and different styles of subduction in the Alpine-Mediterranean region.
Downes, Hilary, Harangi, Szabolcs, Seghedi, I.   +2 more
core   +1 more source

Secondary Plumes Formation Controlled by Interaction of Thermochemical Mantle Plumes With the Mantle Transition Zone

Geophysical Research Letters
The causes and global distribution of intraplate volcanism remain poorly understood, particularly the occurrence of scattered magmatism unrelated to large igneous provinces (LIPs).
X. Zhu, A. Balázs, T. Gerya, Z. Sun
doaj   +1 more source

Geochemical Constraints on the Structure of the Earth's Deep Mantle and the Origin of the LLSVPs

Geochemistry, Geophysics, Geosystems, 2021
Geophysical analysis of the Earth's lower mantle has revealed the presence of two superstructures characterized by low shear wave velocities on the core‐mantle boundary.
Matthew Gleeson, Caroline Soderman, Simon Matthews, Sanne Cottaar, Sally Gibson   +4 more
doaj   +1 more source

Evidence From Microscopy and U–Pb Geochronology as a Clue to the Influence of the Cretaceous Magmatism in the Diagenesis of Pre‐Salt Carbonate Reservoirs in the Santos Basin (Brazil)

Geological Journal, EarlyView.
Carbonates from Santos Basin revealed U–Pb ages correlated with basalt ages (A), suggesting that they were formed during magmatic events. These events placed hot CO2 in the reservoir, which, when mixed with carbonate‐rich cold water (B), led to thermal convection, enabling the formation of the U contained in the carbonates.
Marco António Ruivo de Castro e Brito, Cristiano Leite Sombra, Davy Raeder Brandão, Cleverson Guizan Silva, Sidney Luiz de Matos Mello, Eugênio Vaz dos Santos Neto, Rui Jorge Fernandes Baptista, Ramsés Capilla, Luiz Antônio Pierantoni Gambôa   +8 more
wiley   +1 more source

New Theory of the Earth [PDF]

, 2007
New Theory of the Earth is an interdisciplinary advanced textbook on all aspects of the interior of the Earth and its origin, composition, and evolution: geophysics, geochemistry, dynamics, convection, mineralogy, volcanism, energetics and thermal ...
Anderson, Don L.
core   +2 more sources

Influence of Grain Size Evolution on Mantle Plume and LLSVP Dynamics

Geochemistry, Geophysics, Geosystems
Recent seismic tomography models suggest large‐radius primary plumes originating from the core‐mantle boundary, with grain size variations potentially explaining these observations. Additionally, grain size variations are thought to enhance the long‐term
Yusen Liu, Ting Yang, Kai Wang, Xiong Wang, Yang Li   +4 more
doaj   +1 more source

‘Expression is power’: Gender, residual culture and political aspiration at the Cumnock School of Oratory, 1870–1900

Gender &History, EarlyView.
Abstract This article investigates the ways in which late‐nineteenth‐century students at Northwestern University's Cumnock School of Oratory mobilised elocution training and parlour performance to foster mixed‐gender public discourse. I use student publications to reconstruct parlour meetings in which women and men adapted traditions of conversational ...
Fiona Maxwell
wiley   +1 more source

Horizontal mantle flow controls subduction dynamics [PDF]

, 2017
It is generally accepted that subduction is driven by downgoing-plate negative buoyancy. Yet plate age –the main control on buoyancy– exhibits little correlation with most of the present-day subduction velocities and slab dips. “West”-directed subduction
Dal Zilio, Luca, Doglioni, Carlo, Ficini, Eleonora, Gerya, Taras V.   +3 more
core   +1 more source

Putting the Femme in Feminist: Trans Feminism and the ‘Male Lesbian’ in the American Second Wave

Gender &History, EarlyView.
ABSTRACT A slur, a joke or a post‐structuralist case of mistaken identity. To the extent that the male lesbian has been discussed, she has figured dismissively. Yet throughout the period historicised as American feminism's second wave, potentially thousands of trans femmes organised under this identity. Despite being entirely overlooked in scholarship,
Aino Pihlak, Emily Cousens
wiley   +1 more source