Browsing ELibrary by Author "Halliday A.N."

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ANATEXIS OF LUNAR CUMULATE MANTLE IN TIME AND SPACE: CLUES FROM TRACE-ELEMENT, STRONTIUM, AND NEODYMIUM ISOTOPIC CHEMISTRY OF PARENTAL APOLLO 12 BASALTS

Snyder G.A.; Neal C.R.; Taylor L.A.; Halliday A.N. (1997)

In an effort to elucidate the processes of lunar mantle melting, and the magma evolution of mare basalts within Oceanus Procellarum on the western lunar near-side, we have analyzed seven fine-grained to vitrophyric Apollo ...
COSMIC-RAY PRODUCTION OF TUNGSTEN ISOTOPES IN LUNAR SAMPLES AND METEORITES AND ITS IMPLICATIONS FOR HF-W COSMOCHEMISTRY

Leya I.; Wieler R.; Halliday A.N. (2000)

Excesses and deficiencies in 182W in meteorites and lunar samples relative to the terrestrial 182W atomic abundance have been assigned to the decay of 182Hf (t1/2=9 Ma) and have been used to date metal-silicate fractionation ...
COSMOGENIC TUNGSTEN AND THE ORIGIN AND EARLIEST DIFFERENTIATION OF THE MOON

Lee D.C.; Halliday A.N.; Leya I.; Wieler R.; Wiechert U. (2002)

The decay of formerly live 182Hf with a half-life of 9 Myr results in variations in the abundance of 182W in early solar system objects. Here we demonstrate that major excesses in 182W in some lunar samples are the results ...
DUST PRODUCTION AND DEPOSITION IN ASIA AND THE NORTH PACIFIC OCEAN OVER THE PAST 12 MYR

Pettke T.; Halliday A.N.; Hall C.M.; Rea D.K. (2000)

The silicate fractions of recent pelagic sediments in the central north Pacific Ocean are dominated by eolian dust derived from central Asia. An 11 Myr sedimentary record at ODP Sites 885/886 at 44.7 degrees N, 168.3 degrees ...
EARLY-MIDDLE ARCHAEAN CRUSTAL EVOLUTION DEDUCED FROM LU-HF AND U-PB ISOTOPIC STUDIES OF SINGLE ZIRCON GRAINS

Amelin Y.; Lee D.C.; Halliday A.N. (2000)

We report detailed high precision combined single grain U-Pb and Lu-Hf studies of early zircons to obtain more reliable indications of the extent of mantle depletion and crustal recycling in the Archean. Despite the ...
HF-W INTERNAL ISOCHRONS FOR ORDINARY CHONDRITES AND THE INITIAL 182HF/180HF OF THE SOLAR SYSTEM

Lee D.C.; Halliday A.N. (2000)

Three ordinary chondrites, Forest Vale (H4), Ste. Marguerite (H4) and Richardton (H5) have been studied with 182Hf-182W system (t1/2=9 million years [m.y.]) in order to provide constraints on the initial 182Hf/180Hf for ...
HF-W, SM-ND, AND RB-SR ISOTOPIC EVIDENCE OF LATE IMPACT FRACTIONATION AND MIXING OF SILICATES ON IRON METEORITE PARENT BODIES

Snyder G.A.; Lee D.C.; Ruzicka A.M.; Prinz M.; Taylor L.A.; Halliday A.N. (2001)

We report the first Sm-Nd and Rb-Sr isotopic analyses of silicate inclusions in four IIE iron meteorites: Miles, Weekeroo Station A and B, and Watson. We also report the Hf-W isotopic composition of a silicate inclusion ...
HIGH-PRECISION IN SITU 238U-234U-230TH ISOTOPIC ANALYSIS USING LASER ABLATION MULTIPLE-COLLECTOR ICPMS

Stirling C.H.; Lee D.C.; Christensen J.N.; Halliday A.N. (2000)

We have developed a method for the rapid, in situ measurement of U-Th isotopic compositions at the semimicro scale using laser ablation sampling, combined with multiple collector ICP magnetic sector mass spectrometry ...
IN SEARCH OF LOST PLANETS - THE PALEOCOSMOCHEMISTRY OF THE INNER SOLAR SYSTEM

Halliday A.N.; Porcelli D. (2001)

The depletion of moderately volatile elements in planetesimals and planets is generally considered to be a result of removal of hot nebula gases. This theory can be tested with Sr isotopes. The calculated initial 87Sr/86Sr ...
INDIUM AND TIN IN BASALTS, SULFIDES, AND THE MANTLE

Wen Y.; Halliday A.N.; Der-Chuen L.; Christensen J.N. (1995)

The geochemistry of In and Sn are poorly understood, in part, because of difficulties in obtaining accurate concentrations for these elements in geological materials. Furthermore, In/Sn ratios in sulfides could be sufficiently ...
IR, RU, PT, AND PD IN BASALTS AND KOMATIITES: NEW CONSTRAINTS FOR THE GEOCHEMICAL BEHAVIOR OF THE PLATINUM-GROUP ELEMENTS IN THE MANTLE

Rehkämper M.; Halliday A.N.; Lee D.C.; Fitton J.G.; Wieneke M.; Arndt N.T. (1999)

The concentrations of the platinum-group elements (PGE) Ir, Ru, Pt, and Pd were determined in 18 mantle-derived basalts from a variety of tectonic settings and six komatiites from three locations. All analyses were performed ...
IRON ISOTOPE DIFFERENCES BETWEEN EARTH, MOON, MARS AND VESTA AS POSSIBLE RECORDS OF CONTRASTED ACCRETION MECHANISMS

Poitrasson F.; Halliday A.N.; Lee D.-C.; Levasseur S.; Teutsch N. (2004)

The iron isotope compositions of Shergotty–Nakhla–Chassigny (SNC) meteorites thought to come from Mars, eucrites and diogenites assumed to sample asteroid 4 Vesta, and rocks from the Moon and Earth have been measured using ...
KINETIC ISOTOPE EFFECT DURING REDUCTION OF IRON FROM A SILICATE MELT

Cohen B.A.; Levasseur S.; Zanda B.; Hewins R.H.; Halliday A.N. (2006)

Iron isotopic compositions measured in chondrules from various chondrites vary between ?57Fe/54Fe = +0.9? and -2.0?, a larger range than for igneous rocks. Whether these compositions were inherited from chondrule precursors, ...
LARGE THALLIUM ISOTOPIC VARIATIONS IN IRON METEORITES AND EVIDENCE FOR LEAD-205 IN THE EARLY SOLAR SYSTEM

Nielsen S.G.; Rehk?mper M.; Halliday A.N. (2006)

Lead-205 decays to 205Tl with a half-life of 15 Myr and should have been present in the early solar system according to astrophysical models. However, despite numerous attempts, Tl isotopic measurements of meteorites have ...
LASER 40AR-39AR DATING OF MICROGRAM-SIZE ILLITE SAMPLES AND IMPLICATIONS FOR THIN SECTION DATING

Dong H.; Hall C.M.; Halliday A.N.; Peacor D.R. (1997)

Laser 40Ar-39Ar ages were obtained from a series of replicate illite samples ranging in mass from 14 to 77 μg using vacuum-encapsulated irradiation, and the results were compared with earlier analyses of the same material ...
LEAD ISOTOPES IN NORTH PACIFIC DEEP WATER - IMPLICATIONS FOR PAST CHANGES IN INPUT SOURCES AND CIRCULATION PATTERNS

van de Flierdt T.; Frank M.; Halliday A.N.; Hein J.R.; Hattendorf B.; Günther D.; Kubik P.W. (2003)

The sources of non-anthropogenic Pb in seawater have been the subject of debate. Here we present Pb isotope time-series that indicate that the non-anthropogenic Pb budget of the northernmost Pacific Ocean has been governed ...
ND AND SR ISOTOPES FROM DIAMONDIFEROUS ECLOGITES, UDACHNAYA KIMBERLITE PIPE, YAKUTIA, SIBERIA: EVIDENCE OF DIFFERENTIATION IN THE EARLY EARTH?

Snyder G.A.; Jerde E.A.; Taylor L.A.; Halliday A.N.; Sobolev V.N.; Sobolev N.V. (1993)

Nd and Sr isotopic data from diamond-bearing eclogites found in the Udachnaya kimberlite, Yakutia, Siberia, are interpreted as indicating an early (⩾ 4 Ga) differentiation event, whereby the mantle split into complementary ...
NEW CONSTRAINTS ON THE SOURCES AND BEHAVIOR OF NEODYMIUM AND HAFNIUM IN SEAWATER FROM PACIFIC OCEAN FERROMANGANESE CRUSTS

van de Flierdt T.; Frank M.; Lee D.C.; Halliday A.N.; Reynolds B.C.; Hein J.R. (2004)

The behavior of dissolved Hf in the marine environment is not well understood due to the lack of direct seawater measurements of Hf isotopes and the limited number of Hf isotope time-series obtained from ferromanganese ...
NUCLEOSYNTHETIC ZIRCONIUM ISOTOPE ANOMALIES IN ACID LEACHATES OF CARBONACEOUS CHONDRITES

Schönbächler M.; Rehkämper M.; Fehr M.A.; Halliday A.N.; Hattendorf B.; Günther D. (2005)

Stepwise dissolutions of the carbonaceous chondrites Orgueil (CI), Murchison (CM) and Allende (CV) reveal large nucleosynthetic anomalies for Zr isotopes that contrast with the uniform compositions found in bulk meteorites. ...
RADIOGENIC HF ISOTOPIC COMPOSITIONS OF CONTINENTAL EOLIAN DUST FROM ASIA, ITS VARIABILITY AND ITS IMPLICATIONS FOR SEAWATER HF

Pettke T.; Lee D.C.; Halliday A.N.; Rea D.K. (2002)

The inorganic silicate fraction extracted from bulk pelagic sediments from the North Pacific Ocean is eolian dust. It monitors the composition of continental crust exposed to erosion in Asia. 176Lu/177Hf ratios of modern ...

Browsing ELibrary by Author "Halliday A.N."

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