Search Results - "Borg, Lars E"

The great isotopic dichotomy of the early Solar System by Kruijer, Thomas S., Kleine, Thorsten, Borg, Lars E.

“…The isotopic composition of meteorites and terrestrial planets holds important clues about the earliest history of the Solar System and the processes of planet…”
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A young solidification age for the lunar magma ocean by Gaffney, Amy M., Borg, Lars E.

“…The time at which the lunar magma ocean solidified can be determined from the Lu–Hf isotope systematics of lunar rocks derived from magma sources that formed…”
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Rb-Sr, Sm-Nd and Lu-Hf isotope systematics of the lunar Mg-suite: the age of the lunar crust and its relation to the time of Moon formation by Carlson, Richard W., Borg, Lars E., Gaffney, Amy M., Boyet, Maud

“…New Rb-Sr, 146,147Sm-142,143Nd and Lu-Hf isotopic analyses of Mg-suite lunar crustal rocks 67667, 76335, 77215 and 78238, including an internal isochron for…”
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Evidence for supernova injection into the solar nebula and the decoupling of r-process nucleosynthesis by Brennecka, Gregory A., Borg, Lars E., Wadhwa, Meenakshi

“…The isotopic composition of our Solar System reflects the blending of materials derived from numerous past nucleosynthetic events, each characterized by a…”
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Sm–Nd systematics of lunar ferroan anorthositic suite rocks: Constraints on lunar crust formation by Boyet, Maud, Carlson, Richard W., Borg, Lars E., Horan, Mary

“…We have measured Sm–Nd systematics, including the short-lived 146Sm–142Nd chronometer, in lunar ferroan anorthositic suite (FAS) whole rocks (15415, 62236,…”
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The age of the martian meteorite Northwest Africa 1195 and the differentiation history of the shergottites by Symes, Steven J.K., Borg, Lars E., Shearer, Charles K., Irving, Anthony J.

“…Samarium-neodymium isotopic analyses of unleached and acid-leached mineral fractions from the recently identified olivine-bearing shergottite Northwest Africa…”
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The origin of young mare basalts inferred from lunar meteorites Northwest Africa 4734, 032, and LaPaz Icefield 02205 by Elardo, Stephen M., Shearer Jr, Charles K., Fagan, Amy L., Borg, Lars E., Gaffney, Amy M., Burger, Paul V., Neal, Clive R., Fernandes, Vera A., McCubbin, Francis M.

“…Northwest Africa (NWA) 4734 is an unbrecciated basaltic lunar meteorite that is nearly identical in chemical composition to basaltic lunar meteorites NWA 032…”
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Mechanisms for incompatible-element enrichment on the Moon deduced from the lunar basaltic meteorite Northwest Africa 032 by Borg, Lars E., Gaffney, Amy M., Shearer, Charles K., DePaolo, Donald J., Hutcheon, Ian D., Owens, Thomas L., Ramon, Erick, Brennecka, Greg

“…The lunar meteorite Northwest Africa (NWA) 032 is a low-Ti basalt that has incompatible-element abundances and Th/Sm ratios characteristic of the involvement…”
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Oxygen fugacity and geochemical variations in the martian basalts: implications for martian basalt petrogenesis and the oxidation state of the upper mantle of Mars by Herd, Christopher D.K, Borg, Lars E, Jones, John H, Papike, James J

“…The oxygen fugacity of the Dar al Gani 476 Martian basalt is determined to be quartz-fayalite-magnetite (QFM) -2.3 +/- 0.4 through analysis of olivine, low-Ca…”
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The Evolving Chronology of Moon Formation by Borg, Lars E, Carlson, Richard W

“…Defining the age of the Moon has proven to be an elusive task because it requires reliably dating lunar samples using radiometric isotopic systems that record…”
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Uranium–lead isotope systematics of Mars inferred from the basaltic shergottite QUE 94201 by Gaffney, Amy M., Borg, Lars E., Connelly, James N.

“…Uranium–lead ratios (commonly represented as 238U/ 204Pb = μ) calculated for the sources of martian basalts preserve a record of petrogenetic processes that…”
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Chronological evidence that the Moon is either young or did not have a global magma ocean by Borg, Lars E., Connelly, James N., Boyet, Maud, Carlson, Richard W.

“…Surprise date for lunar sample A new age determination for a Moon rock collected close to the site of the Apollo 16 lander has yielded a surprisingly young age…”
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Prolonged KREEP magmatism on the Moon indicated by the youngest dated lunar igneous rock by Borg, Lars E, Shearer, Charles K, Asmerom, Yemane, Papike, James J

“…Primordial solidification of the Moon (or its uppermost layer) resulted in the formation of a variety of rock types that subsequently melted and mixed to…”
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A review of lunar chronology revealing a preponderance of 4.34-4.37 Ga ages by Borg, Lars E., Gaffney, Amy M., Shearer, Charles K.

“…Data obtained from Sm‐Nd and Rb‐Sr isotopic measurements of lunar highlands’ samples are renormalized to common standard values and then used to define ages…”
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The origin of volatile elements in the Earth-Moon system by Borg, Lars E, Brennecka, Gregory A, Kruijer, Thomas S

“…The origin of volatile species such as water in the Earth-Moon system is a subject of intense debate but is obfuscated by the potential for volatile loss…”
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The formation and evolution of the Moon’s crust inferred from the Sm-Nd isotopic systematics of highlands rocks by Borg, Lars E., Cassata, William S., Wimpenny, Josh, Gaffney, Amy M., Shearer, Charles K.

“…Ages determined for magnesian and ferroan anorthosite crustal rock suites overlap, suggesting they formed contemporaneously about 4.3–4.5 Ga. A notable…”
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The early differentiation of Mars inferred from Hf–W chronometry by Kruijer, Thomas S., Kleine, Thorsten, Borg, Lars E., Brennecka, Gregory A., Irving, Anthony J., Bischoff, Addi, Agee, Carl B.

“…Mars probably accreted within the first 10 million years of Solar System formation and likely underwent magma ocean crystallization and crust formation soon…”
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Accretion timescale and impact history of Mars deduced from the isotopic systematics of martian meteorites by Borg, Lars E., Brennecka, Gregory A., Symes, Steven J.K.

“…High precision Sm−Nd isotopic analyses have been completed on a suite of 11 martian basaltic meteorites in order to better constrain the age of silicate…”
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Isotopic evidence for a young lunar magma ocean by Borg, Lars E., Gaffney, Amy M., Kruijer, Thomas S., Marks, Naomi A., Sio, Corliss K., Wimpenny, Josh

“…Mare basalt sources and ferroan anorthosite suite cumulates define a linear array on a 146Sm/144Nd versus 142Nd/144Nd isochron plot demonstrating these…”
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Onset of magma ocean solidification on Mars inferred from Mn-Cr chronometry by Kruijer, Thomas S., Borg, Lars E., Wimpenny, Josh, Sio, Corliss K.

“…The mantle of Mars probably differentiated through the crystallization of a magma ocean during the first tens of million years (Ma) of Solar System evolution…”
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