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Liu, Y, Spicuzza MJ, Craddock PR, Day JMD, Valley JW, Dauphas N, Taylor LA.  2010.  Oxygen and iron isotope constraints on near-surface fractionation effects and the composition of lunar mare basalt source regions. Geochimica Et Cosmochimica Acta. 74:6249-6262.   10.1016/j.gca.2010.08.008   AbstractWebsite

Oxygen and iron isotope analyses of low-Ti and high-Ti mare basalts are presented to constrain their petrogenesis and to assess stable isotope variations within lunar mantle sources. An internally-consistent dataset of oxygen isotope compositions of mare basalts encompasses five types of low-Ti basalts from the Apollo 12 and 15 missions and eight types of high-Ti basalts from the Apollo 11 and 17 missions. High-precision whole-rock delta(18)O values (referenced to VSMOW) of low-Ti and high-Ti basalts correlate with major-element compositions (Mg#, TiO(2), Al(2)O(3)). The observed oxygen isotope variations within low-Ti and high-Ti basalts are consistent with crystal fractionation and match the results of mass-balance models assuming equilibrium crystallization. Whole-rock delta(56)Fe values (referenced to IRMM-014) of high-Ti and low-Ti basalts range from 0.134 parts per thousand to 0.217 parts per thousand. and 0.038 parts per thousand, to 0.104 parts per thousand, respectively. Iron isotope compositions of both low-Ti and high-Ti basalts do not correlate with indices of crystal fractionation, possibly owing to small mineral-melt iron fractionation factors anticipated under lunar reducing conditions. The delta(18)O and delta(56)Fe values of low-Ti and the least differentiated high-Ti mare basalts are negatively correlated, which reflects their different mantle source characteristics (e.g., the presence or absence of ilmenite). The average delta(56)Fe values of low-Ti basalts (0.073 +/- 0.018 parts per thousand), n = 8) and high-Ti basalts (0.191 +/- 0.020 parts per thousand, n = 7) may directly record that of their parent mantle sources. Oxygen isotope compositions of mantle sources of low-Ti and high-Ti basalts are calculated using existing models of lunar magma ocean crystallization and mixing, the estimated equilibrium mantle olivine delta(18)O value, and equilibrium oxygen-fractionation between olivine and other mineral phases. The differences between the calculated whole-rock delta(18)O values for source regions, 5.57 parts per thousand for low-Ti and 5.30 parts per thousand for high-Ti mare basalt mantle source regions, are solely a function of the assumed source mineralogy. The oxygen and iron isotope compositions of lunar upper mantle can be approximated using these mantle source values. The delta(18)O and delta(56)Fe values of the lunar upper mantle are estimated to be 5.5 +/- 0.27. (2 sigma) and 0.085 +/- 0.040 parts per thousand (2 sigma), respectively. The oxygen isotope composition of lunar upper mantle is identical to the current estimate of Earth's upper mantle (5.5 0.2 parts per thousand), and the iron isotope composition of the lunar upper mantle overlaps within uncertainty of estimates for the terrestrial upper mantle (0.044 +/- 0.030 parts per thousand.). (C) 2010 Elsevier Ltd. All rights reserved.

Liu, Y, Floss C, Day JMD, Hill E, Taylor LA.  2009.  Petrogenesis of lunar mare basalt meteorite Miller Range 05035. Meteoritics & Planetary Science. 44:261-284. AbstractWebsite

Miller Range (MIL) 05035 is a low-Ti mare basalt that consists predominantly of pyroxene (62.3 vol%) and plagioclase (26.4 vol%). Pyroxenes are strongly shocked and complexly zoned from augite (Wo(33)) and pigeonite (Wo(17)) cores with Mg# = 50-54 to hedenbergite rims. Coexisting pyroxene core compositions reflect crystallization temperatures of 1000 to 1100 degrees C. Plagioclase has been completely converted to maskelynite with signs of recrystallization. Maskelynite is relatively uniform in composition (An(94)Ab(6)-An(91)Ab(9)), except at contacts with late-stage mesostasis areas (elevated K contents, An(82)Ab(15)Or(3)). Symplectites (intergrowth of Fe-augite, fayalite, and silica) of different textures and bulk compositions in MIL 05035 suggest formation by decomposition of Ferro-pyroxene during shock-induced heating, which is Supported by the total maskelynitization of plagioclase, melt pockets, and the presence of a relict pyroxferroite grain. Petrography and mineral chemistry imply that crystallization of MIL 05035 Occurred in the sequence of Fe-poor pyroxenes (Mg# = 50-54), followed by plagioclase and Fe-rich pyroxenes (Mg# = 20-50), and finally hedenbergite, Fe-Ti oxides, and minor late-stage phases. Petrography, bulk chemistry, mineral compositions, and the age of MIL 05035 Suggest it is possibly Source crater-paired with Asuka (A-) 881757 and Yamato (Y-) 793169, and may also be launch-paired with Meteorite Hills (MET) 01210. MIL 05035 represents an old (similar to 3.8-3.9 Ga), incompatible element-depleted low-Ti basalt that was not sampled during the Apollo or Luna missions. The light-REE depleted nature and lack of Eu anomalies For this meteorite are consistent with an origin distant from the Procellarum KREEP Terrane, and genesis from an early Cumulate mantle-source region generated by extensive differentiation of the Moon.

Lowder, KB, Allen MC, Day JMD, Deheyn DD, Taylor JRA.  2017.  Assessment of ocean acidification and warming on the growth, calcification, and biophotonics of a California grass shrimp. ICES Journal of Marine Science.   doi:10.1093/icesjms/fsw246   Abstract

Cryptic colouration in crustaceans, important for both camouflage and visual communication, is achieved through physiological and morphological mechanisms that are sensitive to changes in environmental conditions. Consequently, ocean warming and ocean acidification can affect crustaceans’ biophotonic appearance and exoskeleton composition in ways that might disrupt colouration and transparency. In the present study, we measured growth, mineralization, transparency, and spectral reflectance (colouration) of the caridean grass shrimp Hippolyte californiensis in response to pH and temperature stressors. Shrimp were exposed to ambient pH and temperature (pH 8.0, 17 °C), decreased pH (pH 7.5, 17 °C), and decreased pH/increased temperature (pH 7.5, 19 °C) conditions for 7 weeks. There were no differences in either Mg or Ca content in the exoskeleton across treatments nor in the transparency and spectral reflectance. There was a small but significant increase in percent growth in the carapace length of shrimp exposed to decreased pH/increased temperature. Overall, these findings suggest that growth, calcification, and colour of H. californiensis are unaffected by decreases of 0.5 pH units. This tolerance might stem from adaptation to the highly variable pH environment that these grass shrimp inhabit, highlighting the multifarious responses to ocean acidification, within the Crustacea.