Results 261 to 270 of about 724,346 (300)

Mantle Convection for Geologists

, 2011
1. Introduction 2. Context 3. Why moving plates? 4. Solid, yielding mantle 5. Convection 6. The plate mode of convection 7. The plume mode of convection 8. Perspective 9. Evolution and tectonics 10. Mantle chemical evolution 11.
G. Davies
semanticscholar   +1 more source

The Late Cretaceous Impact of the Trindade Mantle Plume: Evidence from Large-volume, Mafic, Potassic Magmatism in SE Brazil

, 1995
S. A. GIBSON*, R. N. THOMPSON, O. H. LEONARDOS, A. P. DICKIN AND J. G. MITCHELL 'DEPARTMENT OF GEOLOGICAL SCIENCES, UNIVERSITY OF DURHAM, SOUTH ROAD, DURHAM DHi 3LE, UK "DEPARTMENTO DE GEOQUIMICA E RECURSOS MINERAIS, INSTITUTO DE GEOCIENCIAS ...
S. Gibson, R. Thompson, O. Leonardos, A. Dickin, J. G. Mitchell   +4 more
semanticscholar   +1 more source

The Deep Roots of Geology: Tectonic History of Australia as expressed by Mantle Anisotropy 

2022
<p>Australia is an old stable continent with a rich geological history. Limitations in sub-surface seismic imaging below the Moho, however, mean that is unclear to what extent, and to what depth, this rich geological history is expressed in the mantle. Studies of seismic anisotropy, which reflect past/present mantle deformation, can offer
openaire   +1 more source

Upper-mantle origin of the Yellowstone hotspot

, 2002
Fundamental features of the geology and tectonic setting of the northeast-propagating Yellowstone hotspot are not explained by a simple deep-mantle plume hypothesis and, within that framework, must be attributed to coincidence or be explained by ...
R. L. Christiansen, G. Foulger, J. R. Evans   +2 more
semanticscholar   +1 more source

Secular Variation in Economic Geology

, 2010
The temporal pattern of ore deposits on a constantly evolving Earth reflects the complex interplay between the evolving global tectonic regime, episodic mantle plume events, overall changes in global heat flow, atmospheric and oceanic redox states, and ...
R. Goldfarb, D. Bradley, D. Leach
semanticscholar   +1 more source

Mantle fluids in the San Andreas fault system

, 1997
Fluids associated with the San Andreas and companion faults in central and south-central California have high3He/4He ratios. The lack of correlation between helium isotopes and fluid chemistry or local geology requires that fluids enter the fault system ...
B. Kennedy, Y. Kharaka, W. Evans, A. Ellwood, D. DePaolo, J. J. Thordsen, G. Ambats, R. Mariner   +7 more
semanticscholar   +1 more source

Diamonds and the geology of Earth mantle carbon

2012
Diamond can crystallize throughout the mantle below about 150 km and while it exists metastably in the crust, it is the only material sampling the ‘very deep’ mantle to depths exceeding 800 km. Diamond has been intensively studied over the last 40 years to provide extraordinary information on Earth’s deep interior.
Shirey S. B., Cartigny P., Frost D. J., Keshav S., NESTOLA, FABRIZIO, NIMIS, PAOLO, Pearson D. G., Sobolev N. V., Walter M. J.   +8 more
openaire   +1 more source

Geology, Mineral Chemistry, and Structure of the Kimberlites at Diavik Diamond Mine: Indicators of Cluster-Scale Cross-Fertilization, Mantle Provenance, and Pipe Morphology

2018
Abstract The Diavik diamond mine includes four diamondiferous kimberlite pipes (A154N, A154S, A418, and A21) and minor kimberlite dikes that are mined by Rio Tinto and Dominion Diamond Corporation. Pipe morphologies from A154S, A154N, and A418 show similar circular near-surface expressions, with expansion of cross-sectional area and ...
M. Stubley, L. Porritt, Jamie Cutts, S. Moss, G. Fomradas, D. Eichenberg, K. Pollock   +6 more
openaire   +2 more sources

Glaciers, ice mantling, gullies and polar caps on Mars: a model-based scenario for the Amazonian climates and geology.

2005
Surface conditions on Mars are currently cold and dry, with water ice unstable on the surface (except near the poles) and no liquid water. However, recent glacier-like landforms have been identified in the tropics and mid-latitudes of Mars, an ice-rich mantling seems to cover both hemisphere above 60°lat., and recent gullies apparently carved by liquid-
Forget, François, Levrard, Benjamin, Montmessin, Franck, Haberle, R. M., Head, James W.   +4 more
openaire   +1 more source

DIAMOND — PREMIER MINERAL FOR UNDERSTANDING THE DEEP GEOLOGY OF EARTH’S MANTLE

Geological Society of America Abstracts with Programs, 2019
D. Graham Pearson, Michael J. Walter, Steven B. Shirey, Fabrizio Nestola   +3 more
openaire   +2 more sources