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The patterns of variation of TiO2 conent during magmatic evolution are different in the so called “orogenic” and “anorogenie” basic associations; these last terms, which are the cause of much misunderstanding, can be replaced by the terms “isotitaniferous” and “anisotitaniferous”. 相似文献
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Design seismic forces depend on Peak Ground Acceleration (PGA) values and on the shape of Response Spectrum (RS) curves dictated by Building Codes or which need to be evaluated in every particular case. The PGA values and RS curves strictly depend on earthquake magnitude and distance, as well as on the regional and local geological conditions. At present, there is no doubt that it is necessary to construct so-called “Site & Region-specific” Building Code provisions reflecting the influence of different magnitude events at different distances that may occur during the life time of the construction, as well as the variety of local ground conditions. A scheme of Uniform Hazard Response Spectra and PGA estimation considering local site response is described in this paper. The assessments of these design parameters are obtained on the basis of Uniform Hazard Fourier spectra using the conception of “dominant earthquakes”. The effect of local geology is included by means of the soil/reference site spectral ratios. 相似文献
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The emplacement of Pyrenean lherzolites is a fascinating problem to tackle because of the unusual location of the lherzolites within sediments and the numerous constraints which are currently available on the Pyrenean belt (plates kinematics, petrology, structural geology, geochemistry, geophysics). Our model [1] represents an attempt to integrate the emplacement of lherzolites within the geodynamic evolution of the Pyrenees. However, on the basis of imprecise statements and observations, and neglecting or quoting incorrectly several previous works. Fischer [2] considers that we failed to address a number of problems relevant to the evolution of the North Pyrenean Fault Zone. Most of his comments find an answer in a careful reading of our article; nevertheless the following points must be clearly emphasized. 相似文献
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D. Offermann M. Jarisch H. Schmidt J. Oberheide K.U. Grossmann O. Gusev J.M. Russell III M.G. Mlynczak 《Journal of Atmospheric and Solar》2007,69(17-18):2139
The “wave turbopause” is defined as the mesospheric altitude level where the temperature fluctuation field indicates a substantial increase in wave amplitudes in the vertical direction.The turbopause altitude is analyzed on the basis of four years of SABER data (2002–2005, Version 1.06). Substantial seasonal and latitudinal variations are found, with some interannual variability also present. Seasonal changes are annual at high latitudes, semi-annual at low latitudes, and a mixture of both at middle latitudes. Southern hemisphere data are similar as in the North if shifted by half a year. Latitudinal variations show a minimum in the tropics and two relative maxima at middle latitudes.The “wave turbopause” is found near to zero-wind lines or low-wind zones (zonal wind). It is compared to rocket and other measurements, and interesting similarities are obtained. The wave turbopause can also be found in the HAMMONIA GCM. A preliminary analysis shows results similar to those of the SABER measurements. 相似文献
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Peter Blattner 《Earth and Planetary Science Letters》1993,120(3-4):511-518
On account of the low porosity of the lithosphere, intracrustal fluids behave very differently from surface fluids, in that they are changing their geochemical and isotopic labels according to the geological environment. Given a heat source, meteoric waters can be supplied plentifully and their rates of throughput in geothermal systems are sufficiently high to exhaust the compositional signals of a given rock buffer. In contrast, fluids exsolved from magma, and subducted fluids, would be supplied at less than about one tenth of the meteoric rate over the life time of a system. Based on up-to-date flow models, the isotopic evolution of meteoric water interacting with crustal rock follows a curved to L-shaped track in the δD versus δ18O plot. Instantaneous (present-day) tie-lines between recharge and discharge are secants of such tracks and can have a range of slopes. At the start of an interaction, waters have δD and δ18O values approaching equilibrium with the original rock composition (water “W1”). Using known hydrogen isotope fractionation factors, W1 values generally plot in the region of “andesite” or “andesitic” waters of various authors. Since the W1 waters have δD values that are on average more positive, and also less variable than those of the meteoric recharges, most tracks and tie-lines have positive slopes, and the plotting of a large number of tie-lines will produce a focus on the field of W1 waters, regardless of the original water source. 相似文献
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Comments and Corrections to: “The Emperor's Old Clothes: An Inconvenient Truth About Currently Accepted Vapor Intrusion Assessment Methods,” and “Emperor's Old Clothes Revisited,” Two Recent Editorials by Mark Kram 总被引：1，自引：0，他引：1 
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下载免费PDF全文 Todd McAlary Tom McHugh Bart Eklund Chris Lutes Eric Suuberg Heidi Hayes Kelly G. Pennell David Folkes Helen Dawson Robert Truesdale Lila Beckley Chase Holton 《Ground Water Monitoring & Remediation》2016,36(3):84-87
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