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61.
鲁西南深埋粘性土物理力学指标多元统计研究 总被引:2,自引:0,他引:2
运用R因子分析和R型聚类两种多元统计分析方法,对鲁西南地区深埋粘性土的20组样的8个物理力学指标数据进行了分析。利用R因子分析方法,揭示了各指标对鲁西南地区深埋粘性土状态和力学性质的影响关系。利用R型聚类分析方法,研究了深部粘性土各物理力学指标之间的相关性,为进一步从物理力学指标对深埋粘性土的特殊状态和力学特性的研究打下基础。 相似文献
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63.
顺义地裂缝成因与顺义-良乡断裂北段第四纪活动性讨论 总被引:3,自引:0,他引:3
本文通过钻孔地层对比方法研究了顺义一良乡断裂北段的第四纪活动性,资料显示该断裂在第四纪期间呈现强弱交替的分期活动特征,距今315万年以来有3个较强活动期和3个较弱活动期,前三者分别距今266~315、171~228、73~147万年,后三者距今分别为228.266、147~171、0~73万年。中更新世晚期以来断裂活动不明显。超量开采地下水导致地面不均匀沉降是造成顺义地裂缝现今活动的主要原因。 相似文献
64.
Spatial character of the gaseous and particulate state compound correlation of urban atmospheric pollution in winter and summer 总被引:1,自引:0,他引:1
XU Xiangde SHI Xiaohui XIE Lian DING Guoan MIAO Qiuju MA Jianzhong ZHENG Xiangdong 《中国科学D辑(英文版)》2005,48(Z2)
The spatial/temporal variation information of atmospheric dynamic-chemical processes at observation site points of the "canopy" boundary of Beijing urban building ensemble and over urban area "surface", as well as the seasonal correlation structure of the gaseous and particulate states of urban atmospheric pollution (UAP) and its seasonal conversion feature at observation points are investigated, using the comprehensive observation data of the Beijing City Air Pollution Observation Experiment (BECAPEX) in winter and summer 2003 with a "point-surface" combined research approach. By using "one dimension spatial empirical orthogonal function (EOF)" principal component analysis (PCA) mode, the seasonal change of gaseous and particulate states of atmospheric aerosols and the association feature of pollutant species under the background of the complicated structure of urban boundary layer (UBL) are analyzed. The comprehensive analyses of the principal components of particle concentrations,gaseous pollutant species, and meteorological conditions reveal the seasonal changes of the complex constituent and structure features of the gaseous and particulate states of UAP to further trace the impact feature of urban aerosol pollution surface sources and the seasonal difference of the component structure of UAP. Research results suggest that in the temporal evolution of the gaseous and particulate states of winter/summer UAP, NOx, CO, and SO2 showed an "in-phase" evolution feature, however, O3 showed an "inverse-phase" relation with other species,all possessing distinctive dependent feature. On the whole, summer concentrations of gaseous pollutants CO, SO2, and NOx were obviously lower than winter ones, especially, the reduction in CO concentration was most distinctive, and ones in SO2 and NOx were next. However, the summer O3 concentration was more than twice winter one. Winter/summer differences in PM10and PM2.5 particle concentrations were relatively not obvious, which indicates that responses of PM10 and PM2.5 particle concentrations to the difference of winter/summer heating period emission sources are far less distinctive than those of NOx, SO2, and CO. The correlation feature of winter/summer gaseous and particulate states depicts that both PM10 and PM2.5 particles were significantly correlated with NOx, and their correlations with NOx are more significant than those with other pollutants. Through PCA, it is found that there was a distinctive difference in the principal component combination structure of winter/summer PM10 and PM2.5 particles: SO2 and NOx dominated in the principal component of winter PM10 and PM2.5 particles; while CO and NOx played the major role in the principal component of summer PM10 and PM2.5 particles. For winter/summer PM10 and PM2.5 particles, there might exist the gaseous and particulate states correlation structures of different "combinations" of such dependent pollutant species. Research results also uncover that the interaction processes of gaseous and particulate states were also related with the vertical structure of UBL, that is to say, the low value layer of UBL O3 concentration was associated with the collocation of atmospheric vertical structures of the low level inversion,inverse humidity, and small wind, which depicts summer boundary layer atmospheric character, i.e.the compound impact of the dependent factor "combination" of wind, temperature, and humidity elements and their collocation structure on the variations of different gaseous pollutant concentrations. Such a depth structure of the extremely low value of O3 concentration in the UBL accords with its "inverse-phase" relation with other gaseous pollutant species. The PCA of meteorological factors associated with PM10 and PM2.5 concentrations also reveals the sensitivity of PM10 and PM2.5 concentration to the combinatory feature of local meteorological conditions. 相似文献
65.
The identification of marine source rocks in the Tarim Basin is debated vigorously. The intention of this paper is to investigate the asphahenes in heavy oils from the Lunnan and Tabe oilfields and Well TD2 with ruthenium-ions-catalyzed oxidation technique (RICO), in order to explore its role in oil-oil and oil-source correlations, The RICO products included n-alkanoic acids, α,ω-di-n-alkanoic acids, branched alkanoic acids, tricyclic terpanoic acids, hopanoic acids, gammacerane carboxylic acid , regular sterane carboxylic acids and 4-methylsterane carboxylic acids. The n-alkyl chains and biomarkers bounded on the asphaltenes were of unsusceptibility to biodegradation. The distribution and absolute concentrations of n-alkanoic acids in the RICO products of heavy oils from the Lunnan and Tabe oilfields are different from those of Well TD2. The biomarkers bounded on the asphahenes, especially steranes, have a distribution trend similar to that of the counterparts in saturates. The sterane carboxylic acids and 4-methylsterane carboxylic acids in the RICO products of heavy oils from the Lunnan and Tahe oilfields, dominated by C30 sterane and C31 4-methylsterane carboxylic acids, respectively, are significantly different from those of the heavy oils of Well TD2, whose dominating sterane and 4-methylsterane carboxylic acids are C28 sterane and C29 4-methylsterane acids, respectively. The RICO products of the asphaltenes further indicate that the Middle-Upper Ordovician may be the main source rocks for heavy oils from the Lunnan and Tabe oilfields. 相似文献
66.
Correlation Fractal and Multifractal Characteristics of Seismic Activity in the Taiwan Area, China 总被引:2,自引:0,他引:2
XU Jiandong HUANG Jianf WEI Fuquan YAN Yunpeng LI Yaping LIN Chien-te Institute of Geology China Earthquake Administration Beijing Chin Earthquake Administration of Fujian Province Fuzhou Fujian China China Aero Geophysical Survey Remote Sensing for Land Resources Beijing China Leader University Tainan Taiwan China 《《地质学报》英文版》2005,79(2):225-232
Based on the analysis of newly collected data of plate tectonics, distribution of active faults and crustal deformation, the Taiwan area is divided into two seismic regions and six seismic belts. Then, correlation fractal dimensions of all the regions and belts are calculated, and the fractal characteristics of hypocenteral distribution can be quantitatively analyzed. Finally, multifractal dimensions Dq and f(α) are calculated by using the earthquake catalog of the past 11 years in the Taiwan area. This study indicates that (1) there exists a favorable corresponding relationship between spatial images of seismic activity described with correlation fractal dimension analysis and tectonic settings; (2) the temporal structure of earthquakes is not single but multifractal fractal, and the pattern of Dq variation with time is a good indicator for predicting strong earthquake events. 相似文献
67.
The Indravati Basin represents an unmetamorphosed and unfossiliferous sequence and shows a broad similarity in lithological association with other Purana Basins of Central India. The carbonates belonging to Indravati Basin have on average, moderately positive δ13 C values (up to +4.5). Numerous successions reported from other parts of world, show similar δ13 C values and contain evidence to suggest that the latest Mesoproterozoic to early Neoproterozoic period may represent an isotopically recognizable interval globally. The elevated δ13 C values of Indravati Basin are also correlatable with other Purana Basins in India including Upper Vindhyan Supergroup. 相似文献
68.
69.
Multidisciplinary analysis including paleomagnetic, sedimentologic, sea-level change, luminescence dating and palynologic research was performed on a 25 m long orientated core taken at Rutten, close to Eemian key localities in the Netherlands. The main goal of our research was to test a possible delayed onset of temperate conditions in this region compared to Southern Europe, occurring within the Last Interglacial. The sediments revealed the presence of the paleomagnetic Blake Event in ca. 10 m of lower-deltaic floodbasin sediments that contain a pollen record covering the Eemian. The position of the Blake Event in relation to the pollen stratigraphy concurs with the earlier studied Neumark Nord 2 site. Paleomagnetic correlation to core MD95-2042 off SW Iberia indicates ca. 5 kyr diachroneity between the pollen-based onset of temperate interglacial conditions between northern and southern Europe. The onset of the Eemian in north-western and central Europe (ca. 121.0 ka) post-dates the Marine Isotope Stage 6/5e transition by ca. 10 kyr. In addition, the Rutten data provide evidence for a relatively long duration of the Blake Event of at least 8 kyr. The late onset of the temperate conditions that define the base of the Eemian, imply that NW Europe with the Eemian type area is not the most suited region to define the beginning of the Last Interglacial and Late Pleistocene for global chronostratigraphic use. 相似文献
70.
The Middle East region, where arid and semi‐arid regions occupy most of the land, is extremely vulnerable to any natural or anthropogenic reductions in available water resources. Much of the observed interannual‐decadal variability in Middle Eastern streamflow is physically linked to a large‐scale atmospheric circulation patterns such as the North Atlantic Oscillation (NAO). In this work, the relationship between the NAO index and the seasonal and annual streamflows in the west of Iran was statistically examined during the last four decades. The correlations were constructed for two scenarios (with and without time lag). The associations between the annual and seasonal streamflows and the simultaneous NAO index were found to be poor and insignificant. The possibility of streamflow forecasting was also explored, and the results of lag correlations revealed that streamflow responses at the NAO signal with two and three seasons delays. The highest Spearman correlation coefficient of 0.379 was found between the spring NAO index and the autumn streamflow series at Taghsimab station, indicating that roughly 14% of the variance in the streamflow series is associated with NAO forcing. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献