Results 91 to 100 of about 16,929 (223)

Geo-neutrinos and Earth's interior

, 2007
The deepest hole that has ever been dug is about 12 km deep. Geochemists analyze samples from the Earth's crust and from the top of the mantle. Seismology can reconstruct the density profile throughout all Earth, but not its composition. In this respect,
Fiorentini, Gianni, Lissia, Marcello, Mantovani, Fabio   +2 more
core   +1 more source

Differing Controls on the Cycling of Neodymium in the Atlantic and the Pacific

Geophysical Research Letters
Neodymium (Nd) isotopes ratios are regarded as a key proxy for past ocean circulation despite unsettled debate on marine Nd cycle controls, which opposes a “top‐down” hypothesis (surface sources dominate) and a “bottom‐up” hypothesis (sedimentary sources
Paige M. Wise, Benoît Pasquier, Seth G. John, Sophia K. V. Hines   +3 more
doaj   +1 more source

Mass Spectrometry in Earth Sciences: The Precise and Accurate Measurement of Time

CHIMIA, 2014
Precise determinations of the isotopic compositions of a variety of elements is a widely applied tool in Earth sciences. Isotope ratios are used to quantify rates of geological processes that occurred during the previous 4.5 billion years, and ...
Urs Schaltegger, Jörn-Frederik Wotzlaw, Maria Ovtcharova, Massimo Chiaradia, Richard Spikings   +4 more
doaj   +1 more source

Recent Development in Radiogenic Isotope Geology

Journal of Geography (Chigaku Zasshi), 1964
Several topics of the research in radiogenic isotope geology are briefly reviewed. This short review consists of four parts; (i) recent development in the instrumentation, (ii) in the methodology, (iii) topics on the mantle-crustal evolution on the basis of Pb, Sr isotope growth and (iv) geochronology of ocean floors.
openaire   +2 more sources

A perspective from extinct radionuclides on a Young Stellar Object: The Sun and its accretion disk

, 2011
Meteorites, which are remnants of solar system formation, provide a direct glimpse into the dynamics and evolution of a young stellar object (YSO), namely our Sun.
Christophe Michel-Lévy M, Das JP, Dauphas N, Grimm RE, Hollenbach DJ, Hudson GB, Hutcheon ID, Jacobsen B, Kita NT, Kleine T, MacPherson GJ, Marc Chaussidon, Mostéfaoui S, Nagashima K, Nagashima K, Nicolas Dauphas, Safronov VS, Tang H, Wetherill GW., Wetherill GW., Yin Q-Z   +20 more
core   +1 more source

Spatial heterogeneity in the radiogenic activity of the lunar interior: Inferences from CHACE and LLRI on Chandrayaan-1

, 2012
In the past, clues on the potential radiogenic activity of the lunar interior have been obtained from the isotopic composition of noble gases like Argon.
Ahmed, S. M., Bhardwaj, Anil, Das, Tirtha Pratim, Kamalakar, J. A., Sridharan, R., Supriya, Gogulapati   +5 more
core   +1 more source

Late Quaternary Mediterranean Outflow Water: implications from radiogenic Nd, Sr, Pb isotopes and clay minerals [PDF]

, 2010
Mediterranean Outflow Water (MOW) is characterised by higher temperatures and salinities than other ambient water masses. MOW spreads at water depths between 500 and 1500 m into the eastern North Atlantic and has been a source of salinity for the ...
Frank, Martin, Haley, Brian A., Stumpf, Roland   +2 more
core  

Along- and Across-Arc Variations in the Southern Volcanic Zone, Chile [PDF]

, 2010
Within Collaborative Research Center (SFB574), we are studying the changes in the chemistry of olivinebearing volcanic rocks along the volcanic front of the Southern Volcanic Zone (SVZ) in Chile and in the rear and backarc in Argentina.
Garbe-Schönberg, C.-Dieter, Hauff, Folkmar, Hoernle, Kaj, Jacques, Guillaume, Lara, Luis, van den Bogaard, Paul, Wehrmann, Heidi   +6 more
core  

Heterogeneous Mantle Metasomatism Controlled by Continental Subduction: Evidence From Post‐Collisional Mafic Rocks in the North Qaidam Orogen

Geochemistry, Geophysics, Geosystems
Post‐collisional mafic rocks not only record geodynamic processes at the end of the orogenic cycle but also retain various clues regarding preceding interactions between subducted slabs and mantle wedges.
Xiangyu Gao, Shengyao Yu, Yu Qi, Lintao Wang, Chuanzhi Li, Xiaocong Jiang, Xingzhou Jiang, Yang Yu   +7 more
doaj   +1 more source

Provenance of clay-sized detrital sediments in the North Sea and the Skagerrak region based on radiogenic Nd-Sr-Hf isotopes and clay mineral compositions: assessing the impact of coastal and seabed erosion

Frontiers in Marine Science
The Skagerrak basin represents the main sink area for fine-grained sediment in the North Sea region and constitutes a natural deposition center for sediments that are supplied from the Atlantic, the Baltic Sea and the surrounding continental margins and ...
Nina Lenz, Timo Spiegel, Ed Hathorne, Klaus Wallmann, Anton Eisenhauer, Martin Frank   +5 more
doaj   +1 more source