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931.
本文在对通辽CK-9井、水文地质条件和水动态特征初步分析的基础上,采用PC-1500计算机,对该井的观测数据与气压、蒸发、降雨、开采、河水位、固体潮、地震波和潜水位等相互关系,进行了定量的相互分析.研究所得结果,对该井水位动态变化和影响因素的关系,提出了新的结论.  相似文献   
932.
StudyofCurieisothermalsurfaceinSichuanBasinandtheseismicareaonitswesternmar┐ginXIANZHANG(张先),XI-FENGHU(虎喜凤),JING-XIUSHEN(沈京秀...  相似文献   
933.
Mössbauer spectra for two riebeckite minerals were collected at temperatures in the range 4.2 to 500 K. The magnetic-ordering temperatures were found to be 33±1 and 31±1 K respectively. Fitting the paramagnetic spectra with a discrete number of doublets (three or four) did not lead to consistent results. Instead, a superposition of an Fe3+ (M2) doublet and one distributed ferrous component was found to produce adequate fits with reasonable parameter values. For both samples, a minor fraction of ferrous ions was observed to be present at the M4 sites and for one of the samples at the M2 sites as well. The temperature variations of the center shifts were well reproduced using the Debye model of the lattice vibrational spectrum to evaluate the second-order Doppler shift. The characteristic Mössbauer temperatures were calculated to be in the range 340–390 K for Fe2+, and 520 K for Fe3+. The temperature dependences of the various ferrous quadrupole splittings could not be explained in terms of the point-charge model and assuming a temperature-independent energy-level scheme for the 5D term. It is suggested that a gradual change with temperature of the orbital-level splittings takes place. All calculations yielded a positive sign for the principal component of the electric field gradient (EFG). The spectrum recorded at 4.2 K for one of the riebeckites was fitted with a superposition of an Fe3+ and a Fe2+ hyperfine-field distribution, the latter one primarily characterizing the Fe2+ (M1) cations. The following relevant hyperfine data were calculated: H hf=161 kOe, ΔE Q=3.11 mm/s, and V zz<0, all referring to the maximum-propability values. For the second riebeckite at 4.2 K, an additional distributed ferrous component could independently be resolved. The two maximum-probability hyperfine fields were found to be 189 and 98 kOe and the corresponding ΔE Q values 3.10 and 2.67 mm/s. Both components exhibit a negative V zz. The subspectra were attributed to M1 and M3 sites respectively. The Fe3+ hyperfine fields are 548+-2 kOe for both riebeckites. The different values found for the Fe3+ quadrupole shift 2?Q for the two samples is explained by a different angle between the hyperfine field and the EFG's principal axis. The magnetic spectra recorded at 15 K and higher, could not be reproduced adequately with reasonable parameter values.  相似文献   
934.
During MONTBLEX 1990, various observational platforms were operated at Kharagpur and the nearby Kalaikunda Air Base. Using the data from all the platforms, one can draw the following conclusions. The temperature and wind data obtained from various sensors have overall compatibility. Sodar wind data indicate the presence of a low level jet at around 300 m above ground. The inversion height may be evaluated from the vertical profile of the sodar back-scatter echo intensity. The sub-synoptic or synoptic scale convergence modulates the inversion height and the presence of cloud-base within the inversion height in turn modulates the sensible heat and momentum fluxes.  相似文献   
935.
上游参数空间的激波分布   总被引:3,自引:1,他引:3       下载免费PDF全文
本文从Rankine-Hugoniot关系出发,采用阿尔文数A1、激波角θ1和气压-磁压比β1作为上游参数,导出了参数空间中激波区边界的解析表达式;讨论了各类激波在参数空间的分布范围和相互关系;指出只有当上游背景阿尔文波速超过声速时,才有可能通过中间激波实现快、慢激波之间的空间连接和时间演化.  相似文献   
936.
937.
The SE-Brazil passive continental margin is characterized by tholeiitic magmatism that is particularly widespread in the marginal Campos basin, facing the inland flood basalts of the adjacent Paranà basin. Campos magmatism is represented by Early Cretaceous (EC; 134–122 Ma) flood basalts and minor Upper Cretaceous-Early Tertiary basalt flows and intrusives, which were emplaced in a basin with attenuated crustal thickness (20 km). Petrography, mineral chemistry, wholerock geochemistry and Sr–Nd isotope composition emphasize that the EC-Campos basalts have suffered extensive seawater interaction which caused enrichment in MgO, FeO total, K2O, Rb and Ba, and depletion in SiO2 and CaO, while Zr, Nb, Y and REE remained virtually constant in samples with loss-on-ignition values less than 4 wt%. In general, Campos basalts have bulkrock chemistry similar to those of the inland Parana tholeiites (140–130 Ma) with relatively low concentrations of incompatible elements and TiO2 (<2 wt%). Batch-melting calculations suggest that Campos basalt genesis requires a garnet-peridotite source and variable degree of melting (9–25%) in order to explain the rare-earth-element (REE) patterns with chondrite normalised La/Yb(N) ratio ranging from 0.9–1.0 to 4.4–7.1. The Sr–Nd isotopic data for the slightly altered Campos basalts, of both Early Cretaceous and Upper Cretaceous-Early Tertiary age, plot close to bulk earth, or in the enriched quadrant of the mantle array. Inter-element (La, Zr, Nb, Ba) ratios preclude for the Campos (and Paranà) basalt genesis any significant participation of N-type (Zr/Nb>16) MORB (mid-ocean-ridge basalt) mantle in simple binary mixing models. On the whole, the Early Cretaceous Campos basalts appear as an easterly, younger extension of the northern Paranà volcanism and probably erupted during early stages of the major riftingprocesses which caused continental thinning. It is notable that in the Campos marginal basin both the basalt magmatism contemporaneous with the continental break-up, as well as that which occurred after the S. America-Africa separation, appears substantially related to subcontinental lithosphere and a Dupal-like OIB (ocean-island basalt) (e.g. Tristan da Cunha) source components.  相似文献   
938.
采用经验总结法和文献研究法,通过对沥鼻峡热储构造上的温泉和地热井勘查资料进行系统研究,发现沥鼻峡背斜具有典型的层状热储结构特征,是目前华蓥山复式背斜钻获地热水水温最低的热储构造,地热水以硫酸钙型水质为主,目前已知地热井和温泉具有水温普遍低于37℃和水量衰减较明显的特征.初步认为钻获地热水温低可能与构造有一定的关系.  相似文献   
939.
通过多变(相关分析)和趋势分析等统计方法对宏观调查数据进行了解释.这种方法使我们通过评定不同宏观效应叠加的程度、估计调查数据的不确定性更客观地评定烈度.通过滤波确定烈度场的区域分量,使我们消除观测中的局部变化.给出了选取适当滤波参数的准则.本文应用这一方法对发生在意大利的一次地震的调查数据进行了处理.  相似文献   
940.
Bulletin of Volcanology - Correlations on the eruptive behaviour of the volcano of Capelinhos (Fayal island) in 1957–58, with (a) solar activity, and (b) earth-tide amplitudes, by way of a...  相似文献   
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