Results 81 to 90 of about 10,806 (258)

Continental growth and the crustal record [PDF]

open access: yes, 2013
Funding: Natural Environment Research Council (NERC) (grant NE/J021822/1) and the University of St. Andrews.The continental crust is the archive of Earth history.
Hawkesworth, Chris   +2 more
core   +1 more source

Oxygen isotope variability in the IIIAB iron meteorites and their relationship to main group pallasites

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract The light element distribution in planetary cores and the processes driving core evolution in rocky planets are poorly understood. Magmatic iron meteorites are samples from the cores of ancient embryonic planetesimals and therefore provide a window into the processes governing core evolution. We performed high precision oxygen isotope analyses
R. J. Windmill   +4 more
wiley   +1 more source

Time constraints on the formation of lithospheric mantle beneath cratons: a re-Os isotope and platinum group element study of peridotite xenoliths from northern Canada and Lesotho, [PDF]

open access: yes, 2001
Understanding the generation and evolution of cratonic lithospheric keels requires detailed knowledge of their age, timescale of formation, and the relationship between the crust and mantle part of the lithosphere.
Irvine, Gordon James
core  

Mafic alkaline metasomatism in the lithosphere underneath East Serbia: evidence from the study of xenoliths and the host alkali basalts [PDF]

open access: yes, 2010
Effects of mafic alkaline metasomatism have been investigated by a combined study of the East Serbian mantle xenoliths and their host alkaline rocks.
H. Downes   +9 more
core   +1 more source

Crystallization of dmisteinbergite (hexagonal CaAl2Si2O8) from type B CAI analog melt

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract Dmisteinbergite is a metastable polymorph of CaAl2Si2O8, which has been found in calcium−aluminum‐rich inclusions (CAIs) in chondrites, although anorthite is the predominant CaAl2Si2O8 phase in natural type B CAIs. The occurrence/absence of igneous dmisteinbergite would put tighter constraints on the thermal history of CAIs.
Yasuaki Tsuruoka   +6 more
wiley   +1 more source

Magmatism of the Kenya Rift Valley : a review. [PDF]

open access: yes, 2003
Tertiary–Recent magmatism in the Kenya Rift Valley was initiated c. 35 Ma, in the northern part of Kenya. Initiation of magmatism then migrated southwards, reaching northern Tanzania by 5–8 Ma.
MacDonald, Raymond
core  

Geochemical Constraints on Spatial‐Temporal Distribution and Origin of Anomalous Mantle in the Western Pacific Basins

open access: yesGeochemistry, Geophysics, Geosystems
Seafloor basalt samples recovered from the Caroline Basin (CB), the Parece Vela Basin (PVB), and the Western Philippine Sea Plate (WPSP) are analyzed for whole‐rock major and trace elements (including H2O), Sr‐Nd‐Pb‐Hf isotopes and 40Ar‐39Ar age‐dating ...
Guo‐Liang Zhang   +3 more
doaj   +1 more source

Characterization of coesite‐bearing impact melt glass from the Hapcheon crater, Korea: Trimodal phase architecture, shock metamorphism, and implications for 40Ar/39Ar geochronology

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract We present the first micrometer‐scale, phase‐resolved compositional characterization of impact melt glass from the Hapcheon crater (~1.4 km apparent diameter), the first confirmed impact structure on the Korean Peninsula, integrating EPMA‐WDS (5 μm spot), confocal Raman spectroscopy (<1 μm spot), XRD, and 40Ar/39Ar step‐heating geochronology ...
Jin‐Young Lee   +2 more
wiley   +1 more source

δ³⁷Cl: the geochemistry of chlorine isotopes [PDF]

open access: yes, 1994
In this thesis the geochemistry of the stable isotopes of chlorine will be examined. Chlorine is one of the halogens, the seventh group in the periodic system of elements.
Eggenkamp, H.G.M.   +3 more
core  

Australian plate motion and topography linked to fossil New Guinea slab below Lake Eyre [PDF]

open access: yes, 2015
Unravelling causes for absolute plate velocity change and continental dynamic topography change is challenging because of the interdependence of large-scale geodynamic driving processes.
Schellart, W. P.   +4 more
core   +1 more source

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