Boulder 1, Station 2, Apollo 17: Petrology and petrogenesis     

Graham Ryder  Douglas B. Stoeser  Ursula B. Marvin  Janice F. Bower  John A. Wood 《Earth, Moon, and Planets》1975,14(3-4):327-357

Boulder 1, Station 2, Apollo 17 is a stratified boulder containing dark clasts and dark-rimmed light clasts set in a light-gray friable matrix. The gray to black clasts (GCBx and BCBx) are multigenerational, competent, high-grade metamorphic, and partially melted breccias. They contain a diverse suite of lithic clasts which are mainly ANT varieties, but include granites, basaltic-textured olivine basalts, troctolitic and spinel troctolitic basalts, and unusual lithologies such as KREEP norite, ilmenite (KREEP) microgabbro, and the Civet Cat norite, which is believed to be a plutonic differentiate. The GCBxs and BCBxs are variable in composition, averaging a moderately KREEPy olivine norite. The matrix consists of mineral fragments derived from the observed lithologies plus variable amounts of a component, unobserved as a clast-type, that approximates a KREEP basalt in composition, as well as mineral fragments of unknown derivation. The high-temperature GCBxs cooled substantially before their incorporation into the friable matrix of Boulder 1. The light friable matrix (LFBx) is texturally distinct from the competent breccia clasts and, apart from the abundant ANT clasts, contains clasts of a KREEPy basalt that is not observed in the competent breccias. The LFBx lacks such lithologies as the granites and the Civet Cat norite observed in the competent breccias and in detail is a distinct chemical as well as textural entity. We interpret the LFBx matrix as Serenitatis ejecta deposited in the South Massif, and the GCBx clasts as remnants of an ejecta blanket produced by an earlier impact. The source terrain for the Serenitatis impact consisted of the competent breccias, crustal ANT lithologies, and the KREEPy basalts, attesting to substantial lunar activity prior to the impact. The age of the older breccias suggests that the Serenitatis event is younger than 4.01±0.03 b.y.  相似文献   

BEHAVIOUR OF NITRATE IN A HETEROGENEOUS FIELD SOIL: MEASUREMENTS AND MODELLING ON DIFFERENT SPATIAL SCALES     

JÜRG HOSANG 《水文研究》1996,10(9):1193-1208

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SPECTROPHOTOMETRIC DETERMINATION OF FERROUS IRON IN EIGHTEEN UNITED STATES GEOCHEMICAL REFERENCE STANDARDS     

Charles B. Bruce  Jr.  Nathan W. Bower 《Geostandards and Geoanalytical Research》1987,11(1):41-42

Iron (II) oxide in 50 mg samples of silicate rocks, deposits, and soils is measured after digestion with HF and HCl in the presence of ICl. The iodine produced is measured spectrophotometrically. Results are presented for the eighteen available USGS geochemical reference standards including the GXR series.  相似文献   

Processing of oxidised nitrogen compounds by passage through winter-time orographic cloud     

R. N. Colvile  T. W. Choularton  J. N. Cape  B. J. Bandy  K. N. Bower  R. A. Burgess  T. J. Davies  G. J. Dollard  M. W. Gallagher  K. J. Hargreaves  B. M. R. Jones  S. A. Penkett  R. L. Storeton-West 《Journal of Atmospheric Chemistry》1996,24(3):211-239

Four case studies are described, from a three-site field experiment in October/November 1991 using the Great Dun Fell flow-through reactor hill cap cloud in rural Northern England. Measurements of total odd-nitrogen nitrogen oxides (NO _y ) made on either side of the hill, before and after the air flowed through the cloud, showed that 10 to 50% of the NO _y , called NO _z , was neither NO nor NO₂. This NO _z failed to exhibit a diurnal variation and was often higher after passage through cloud than before. No evidence of conversion of NO _z to NO₃ ^- in cloud was found. A simple box model of gas-phase chemistry in air before it reached the cloud, including scavenging of NO₃ and N₂O₅ by aerosol of surface area proportional to the NO₂ mixing ratio, shows that NO₃ and N₂O₅ may build up in the boundary layer by night only if stable stratification insulates the air from emissions of NO. This may explain the lack of evidence for N₂O₅ forming NO₃ ^- in cloud under well-mixed conditions in 1991, in contrast with observations under stably stratified conditions during previous experiments when evidence of N₂O₅ was found. Inside the cloud, some variations in the calculated total atmospheric loading of HNO₂ and the cloud liquid water content were related to each other. Also, indications of conversion of NO _x to NO _z were found. To explain these observations, scavenging of NO _x and HNO₂ by cloud droplets and/or aqueous-phase oxidation of NO₂ ^- by nitrate radicals are considered. When cloud acidity was being produced by aqueous-phase oxidation of NO _x or SO₂, NO₃ ^- which had entered the cloud as aerosol particles was liberated as HNO₃ vapour. When no aqueous-phase production of acidity was occurring, the reverse, conversion of scavenged HNO₃ to particulate NO₃ ^-, was observed.  相似文献   

Comment on “The chemical variation of moldavite tektites: Simple mixing of terrestrial sediments” by Th. Meisel,J. M. Lange and U. Krähenbühl     

WOLF VON ENGELHARDT  J RG ARNDT 《Meteoritics & planetary science》1998,33(3):535-535

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The halo mass function from the dark ages through the present day     

Darren S. Reed  Richard Bower  Carlos S. Frenk  Adrian Jenkins  Tom Theuns 《Monthly notices of the Royal Astronomical Society》2007,374(1):2-15

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The stellar mass content of distant galaxy groups     

Michael L. Balogh  Dave Wilman  Robert D. E. Henderson  Richard G. Bower  David Gilbank  Richard Whitaker  Simon L. Morris  George Hau  J. S. Mulchaey  A. Oemler  Jr    R. G. Carlberg 《Monthly notices of the Royal Astronomical Society》2007,374(3):1169-1180

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Resolved spectroscopy of a gravitationally lensed L* Lyman-break galaxy at z∼ 5     

A. M. Swinbank  R. G. Bower  Graham P. Smith  R. J. Wilman  Ian Smail  R. S. Ellis  S. L. Morris  J.-P. Kneib 《Monthly notices of the Royal Astronomical Society》2007,376(2):479-491

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A panoramic Hα imaging survey of the  z= 0.4  cluster Cl 0024.0+1652 with Subaru     

Tadayuki Kodama  Michael L. Balogh †  Ian Smail  Richard G. Bower  Fumiaki Nakata 《Monthly notices of the Royal Astronomical Society》2004,354(4):1103-1119

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Revisiting the cosmic cooling crisis     

Michael L. Balogh  Frazer R. Pearce  Richard G. Bower  Scott T. Kay 《Monthly notices of the Royal Astronomical Society》2001,326(4):1228-1234

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