Palaeomagnetic Directions and Pole Positions, Part VI Numbers 6/1 to 6/73     

E. Irving  P. M. Stott 《Geophysical Journal International》1963,8(2):249-257

  相似文献   

Reply     

Irving Michelson 《Pure and Applied Geophysics》1970,82(1):288-289

  相似文献   

STATISTICAL METHODS IN ROCK MAGNETISM     

G. S. Watson  E. Irving 《Geophysical Journal International》1957,7(6):289-300

Summary. This paper describes the statistical techniques available to the experimenter in palaeomagnetic work. The theory of these methods is based on an assumed probability distribution of errors. It is shown that the mathematical requirements of this distribution are obeyed by the observations from rock samples which are known to possess a stable magnetization; observations on rocks with unstable magnetization however do not conform to it. A theoretical derivation is given for this probability distribution.
The problem of estimating the mean direction of magnetization of a geological formation has in recent years become a matter of the greatest geophysical interest since it is from such estimates that the position of the pole of the Earth in past geological ages is determined. This problem is largely one of the judicious choice of samples and a procedure is suggested whereby such estimates may be achieved with the greatest sample economy.  相似文献   

Northwest Africa 8418: The first CV4 chondrite     

G. J. MacPherson  K. Nagashima  A. N. Krot  S. M. Kuehner  A. J. Irving  K. Ziegler  L. Mallozzi  C. Corrigan  D. Pitt 《Meteoritics & planetary science》2023,58(1):135-157

Northwest Africa (NWA) 8418 is an unusual chondrite whose properties do not exactly match those of any other known chondrite. It has similarities to the CV (Vigarano group), CK (Karoonda group), and CL (Loongana group) chondrites, but its abundance of large calcium-aluminum-rich inclusions (CAIs) and the low NiO content (<0.2 wt%) of its matrix olivine ally it most closely with the CV group. The absence of grossular, monticellite, wollastonite, and sodalite from the alteration products of the CAIs; the magnesium-rich nature of the matrix olivines (Fa₃₈) relative to that of the CV3 chondrites (~Fa₅₀); and the presence of secondary Na-bearing plagioclase and chlorapatite indicate a metamorphic temperature >600 °C. NWA 8418 contains kamacite, taenite, and troilite, and lacks magnetite and pentlandite. We propose that NWA 8418 be reclassified as a reduced CV4 chondrite, which makes it the first CV chondrite of petrologic type 4.  相似文献   

Collisional excitation of metastable oxygen O(D) atoms through the B∑_u channel of O₂     

M. J. Jamieson  M. Finch  R. S. Friedman  A. Dalgarno 《Planetary and Space Science》1992,40(12):1719-1721

Pectroscopic data on the shifts and widths of the energy levels of molecular oxygen have been used in the empirical construction of a diabatic potential matrix that characterizes the interactions of the B³∑⁻_u state with the ⁵Π_u, 2³∑⁺_u, ³Π_u and ¹Π_u states. The diabatic potential matrix is u theory formulation to calculate the cross-sections for the excitation of O(¹D) atoms in collisions of two O(³P) atoms. Total cross-sections are obtained by adding the excitation from the ³Π_g, channel. The rate coefficient for quenching of O(¹D) by O(³P) is evaluated as a function of temperature. The values conflict with a recent analysis of the emission of the oxygen red line in the upper atmosphere.  相似文献   

Comment on the ‘loss due to imperfect fringe rotation in VLBI correlators’ revisited     

P. A. Friedman 《Astrophysics and Space Science》1987,137(1):189-189

  相似文献   

The Cosmic Origins Spectrograph: on-orbit instrument performance     

S. Osterman  J. Green  C. Froning  S. B��land  E. Burgh  K. France  S. Penton  T. Delker  D. Ebbets  D. Sahnow  J. Bacinski  R. Kimble  J. Andrews  E. Wilkinson  J. McPhate  O. Siegmund  T. Ake  A. Aloisi  C. Biagetti  R. Diaz  W. Dixon  S. Friedman  P. Ghavamian  P. Goudfrooij  G. Hartig  C. Keyes  D. Lennon  D. Massa  S. Niemi  C. Oliveira  R. Osten  C. Proffitt  T. Smith  D. Soderblom 《Astrophysics and Space Science》2011,335(1):257-265

The Cosmic Origins Spectrograph (COS) was installed in the Hubble Space Telescope in May, 2009 as part of Servicing Mission 4 to provide high sensitivity, medium and low resolution spectroscopy at far- and near-ultraviolet wavelengths (FUV, NUV). COS is the most sensitive FUV/NUV spectrograph flown to date, spanning the wavelength range from 900 Å to 3200 Å with peak effective area approaching 3000 cm². This paper describes instrument design, the results of the Servicing Mission Orbital Verification (SMOV), and the ongoing performance monitoring program.  相似文献   

Distribution of trace elements between garnet megacrysts and host volcanic liquids of kimberlitic to rhyolitic composition     

Anthony J. Irving  Frederick A. Frey 《Geochimica et cosmochimica acta》1978,42(6):771-787

Abundances of rare earth elements, Hf, Sc, Co, Cr and Th in garnet megacrysts and their volcanic hosts or matrices are used to estimate garnet/liquid partition coefficients for these elements. Samples include pyropes from kimberlite and highly alkalic basalts, almandines from basalt andesite, dacite, rhyodacite and rhyolite and a spessartine-almandine from alaskite. The pyrope/host partition coefficients are fairly uniform and agree with experimental data within a factor of 2. The almandine/matrix data show more scatter (due in part to impurities in the garnet separates) but the partition coefficients tend to increase with increasing $\text{Si}\text{O}$ ratio of the matrix. The almandine/matrix partition coefficients are up to a factor of 10 higher than the pyrope/host partition coefficients. The spessartine-almandine is strongly enriched in heavy rare earths (~ 5000 times chondrites), Y, Sc and Co. The wide variation in garnet/liquid partition coefficients from kimberlites to rhyolites cannot be explained as an effect of temperature and we conclude that a major factor is the composition of the melt from which the garnet crystallized.  相似文献   

Palaeomagnetic Directions and Pole Positions, Part VII Numbers 7/1 to 7/80     

E. Irving 《Geophysical Journal International》1965,9(2-3):185-194

  相似文献   

Excursion to Wokingham,Easthampstead and Ascot: Saturday,July 18th, 1885     

A. Irving 《Proceedings of the Geologists' Association. Geologists' Association》1885,9(4):222-224

  相似文献