Should Quaternary sea-level changes be used to correct glacier ELAs, vegetation belt altitudes and sea level temperatures for inferring climate changes?   总被引：1，自引：0，他引：1  

Henry A. Osmaston 《Quaternary Research》2006,65(2):244-251

Changes in the altitudes of glacier snowlines (ELAs) and the altitudes of montane vegetation belts (VBAs) measure Quaternary climatic change. An accepted ‘correction’ to such changes by deducting the amount of contemporary sea level fall is wrong, since the air displaced by the ice sheets approximately fills the space left by the falling sea level and so there is no overall downward movement of the troposphere. This also causes a reduced cooling at the lowered sea level relative to that at the former inter-glacial sea level, about 1°C at the Las Glacial Maximum, which reduces the discrepancies previously noted by others between terrestrial and marine estimates of sea-level cooling. The change in temperature is indicated by the product of the ELA or VBA lowering and the environmental lapse rate (ELR). Prior estimates of ΔELA (−900 ± 135 m) and ELR (−6° ± 0.1°C km⁻¹) would indicate a cooling of −5.4°C at interglacial sea level and −4.4°C at glacial sea level, although glacial-period ELRs are not known reliably. Established ELA corrections for local epeirogenic uplift or subsidence are appropriate.  相似文献   

Conference report     

Gordon Winder  Matthew Henry 《New Zealand geographer》2006,62(1):2-2

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Fluid inclusions in high-grade gneisses of the Kapuskasing structural zone,Ontario: metamorphic fluids and uplift/erosion path     

Roberta L. Rudnick  Lewis D. Ashwal  Darrell J. Henry 《Contributions to Mineralogy and Petrology》1984,87(4):399-406

Fluid inclusions in quartz grains from five samples of high-grade rocks (two paragneisses, an amphibolite, a mafic gneiss and a tonalite dike) from the 2.7 Ga Kapuskasing structural zone (KSZ), Ontario, were examined with petrographic, microthermometric and laser Raman techniques. Three types of fluid inclusions were observed: CO₂-rich, H₂O-rich and mixed CO₂-H₂O. CO₂-rich fluid inclusions are pseudosecondary or secondary in nature and are generally pure CO₂; a few contain varying amounts of CH₄·H₂O-rich fluid inclusions are secondary in nature, contain variable amounts of dissolved salts, and generally contain daughter crystals. Mixed CO₂-H₂O fluid inclusions occur where trails of H₂O-rich inclusions intersect trails of CO₂-rich inclusions. Isochores for high density (p=1.03 g/cm³) pseudosecondary, pure CO₂ inclusions intersect the lower pressure portion of the estimated P-T field for high-grade metamorphism, implying that pure CO₂ was the peak metamorphic fluid. The variable CH₄ content of CO₂ inclusions within graphite-bearing samples suggests that CH₄ was introduced locally after the formation of the CO₂ inclusions; however the origin of the CH₄ remains problematic. An aqueous fluid clearly penetrated the gneisses after the peak metamorphism (during uplift/erosion), forming secondary inclusions and contributing to the minor retrogressive hydration observed in these rocks. The presence of the pseudosecondary, high-density CO₂ inclusions in quartz crystals in the KSZ rocks constrains the uplift/ erosion path for the KSZ to one of simultaneous decrease in pressure and temperature.  相似文献   

Radiocarbon tracer measurements of atmospheric hydroxyl radical concentrations     

Campbell  M. J.  Farmer  J. C.  Fitzner  C. A.  Henry  M. N.  Sheppard  J. C.  Hardy  R. J.  Hopper  J. F.  Muralidhar  V. 《Journal of Atmospheric Chemistry》1986,4(4):413-427

Radiochemical techiques have many untapped applications in atmospheric chemistry, especially when great sensitivity is required. We describe the application of these techniques to the measurement of hydroxyl radical concentrations in the troposphere.  相似文献   

Interprétation quantitative de l'anisotropie de susceptibilité magnétique     

Bernard Henry 《Tectonophysics》1983,91(1-2)

We propose a model in which the magnetic susceptibility anisotropy is considered as resulting from the distinct properties of two rock components. This model suggests that differences in the susceptibility ellipsoid can be principally related to mineralogical variations. Thus, some difficulties in the quantitative interpretation of anisotropy data may be explained. This model is consistent with a detailed analysis carried on Dalradian rocks from Scotland.A new methodology of anisotropy analysis is derived. It is based on the fact that, in specimens from a same sample, the susceptibility ellipsoid often varies, but relations nevertheless exist between values of the principal and mean susceptibilities. For each sample, measurements are made on 6–12 specimens. The study of the relations between principal and mean susceptibilities permits separation of the anisotropies of the rock components, the anisotropy determination appearing the best for the high susceptibility component.

Résumé

L'examen d'un modèle de roche, où l'anisotropie est considérée comme résultant des propriétés de deux constituants, montre que l'ellipsoïde de susceptibilité dépend fortement de la composition minéralogique. Ainsi s'expliquent certaines difficultés de l'interprétation quantitative des résultats d'anisotropie. Ce modèle est testé avec succès sur une série du Dalradien d'Écosse.Une nouvelle méthodologie d'analyse de l'anisotropie en découle. Elle est basée sur la constatation que l'ellipsoïde de susceptibilité présente souvent des fluctuations dans les différents spécimens taillés dans un même échantillon, et que des relations simples existent cependant entre les différentes valeurs des susceptibilités principales et moyenne. Pour chaque échantillon, les mesures sont faites sur 6–12 spécimens. L'étude des relations entre susceptibilités principales et moyenne permet une séparation des anisotropies des constituants de la roche, la détermination de l'anisotropie semblant d'autant meilleure que la susceptibilité est plus forte.  相似文献   

A paleomagnetic and isotopic age for the Wackerfield Dyke of northern England     

D.H. Tarling  J.G. Mitchell  Henry Spall 《Earth and Planetary Science Letters》1973,18(3):427-432

The Wackerfield Dyke is exposed in northern England and its field relationships suggest it could be related to the Eocene Mull Dyke Swarm. Wackerfield Dyke specimens taken from below the zone of surface weathering have a natural remanent magnetization that is extremely stable to thermal and alternating field demagnetization. Stability is expected because the Fe-Ti oxides are highly oxidized. The stable magnetization is identical with a primary remanence that can be isolated from certain samples of the Whin Sill of northern England, and gives a mean pole at 175°E, 22°N (dp = 2°, dm = 3°). An Upper Carboniferous age for the Wackerfield Dyke is confirmed by a K-Ar whole rock age of 303 my.  相似文献   

Geological investigations of the North Pacific | James D. Hays (Editor), 1970. Memoir 126, Geological Society of America,Boulder, Colo., 323 pp., U.S. $ 15.00 (Place orders from continental Europe with Office International de Librairie, 30 Avenue Marnix,B-1050 Brussels)     

Henry W. Menard 《Earth》1973,9(1):78

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Preliminary tests on large-scale suppression of warm fog by means of giant monodisperse particulates. Part I. The first Ghedi-Monte Orfano experiment     

Alberto C. Montefinale  Henry M. Papee 《Pure and Applied Geophysics》1970,83(1):167-172

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Recent advances in the chemistry and properties of atmospheric nucleants: a review     

Alberto C. Montefinale  Tito Montefinale  Henry M. Papée 《Pure and Applied Geophysics》1971,91(1):171-210

Summary A survey is carried out of recent progress in the investigation of weather-active atmospheric nucleants. Emphasis is placed on the work date during the last decade, and some resulting implications are discussed.  相似文献   

Eclogite xenoliths from stockdale kimberlite,Kansas     

Henry O. A. Meyer  Douglas G. Brookins 《Contributions to Mineralogy and Petrology》1971,34(1):60-72

Six kimberlite pipes of late Cretaceous or Tertiary age occur in Riley Co., east-central Kansas. Within the pipes xenoliths of local sedimentary and exotic igneous rocks are common, especially in the Stockdale pipe. Igneous rocks which occur as xenoliths include granite, gabbro, metagabbro, pyroxenite and eclogite. In the eclogites omphacitic clinopyroxene (approx. Di₅₂Jd₂₄mol%) and pyropic garnet (approx. Py₄₇Al₃₅Gr₁₂mol%) are the predominant minerals with subordinate amounts of rutile and sulphides (pyrrotite-pentlandite (?)-chalcopyrite). Interstitial kaersutitic amphibole is a minor constituent. The eclogites are chemically equivalent to olivine-basalt. The texture, composition and mineralogy of the eclogites from Kansas are similar to those of eclogites from kimberlite pipes in South Africa and Siberia. Whereas the rocks from these latter localities display a range in composition, those examined to date from Kansas are of fairly restricted composition. Furthermore it seems probable that the eclogites from Stockdale formed under limited P-T conditions within the mantle. This is the first record of such eclogites on the North American continent.  相似文献