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241.
ZHAO Xi PANG Xiaoping ZHANG Shengli ZHANG Xiang 《地球空间信息科学学报》2007,10(1):75-78
True color image city map is a sort of new-style map which combines the high resolution image and map symbols and shows both advantages in visualization. At the same time, the map unification and harmonization should be taken into account dur-ing the design process, since some visual conflicts appear when map symbols overlaid on the true color image. The objective of this research is to explore the rules in the process of true color image city map design based on chromatic and aesthetic knowledge. At the end, taking the Image Atlas of Guangzhou as an example, image color adjustment, road network presentation, and symbol de-signing issues will be discussed in the application. 相似文献
242.
Quantitative estimate of residual or palaeo-oil column height 总被引:1,自引:0,他引:1
Keyu Liu Xiongqi Pang Zhenxue Jiang Peter Eadington 《Journal of Geochemical Exploration》2006,89(1-3):239
A method to quantitatively estimate residual or palaeo-oil column heights is proposed using criteria based on the presence or absence of oil shows in a single heterogeneous reservoir rock sample. The residual or palaeo-oil column height below the sample is constrained through the determination of the displacement pressure of regions in the sample containing oil shows (Pd-o) and the displacement pressure for regions that are devoid of any evidence of oil shows (Pd-w). The height of the residual or palaeo-oil column below the sampling depth can then be estimated to be greater than the equivalent height corresponding to Pd-o, but less than the height corresponding to Pd-w. Three examples from two basins in China were investigated using the method to determine their residual and palaeo-oil column heights. 相似文献
243.
Gas charging history of the Yingcheng Formation igneous reservoir in the Xujiaweizi Rift, Songliao Basin, China 总被引:2,自引:0,他引:2
Systematic analysis of fluid inclusions was carried out on 34 samples from the Yingcheng Formation igneous reservoir of the Xujiaweizi rift, Songliao Basin, China. On the basis of petrographic characterization, the results of the microthermometric analyses indicated that the Yingcheng Formation igneous reservoir trapped six clusters of pure aqueous inclusions, and only four of them have the coeval gas-bearing aqueous inclusions been detected in the analyses. So the Yingcheng Formation igneous reservoir experienced four gas charging events during its evolutionary history. Combined with the research results of burial history and cap rocks, the four gas charging events happened during the time interval from 120 to 85 Ma, and every charging time is no more than 10 Ma. The main gas charging is the third, which happened during the time interval from 105 to 95 Ma. 相似文献
244.
Zhonghe Pang 《Journal of Geochemical Exploration》2006,89(1-3):306
In arc-type geothermal systems along the circum-Pacific rim, low pH well discharges in the geothermal systems of Japan and the Philippines are more enriched in oxygen-18 or deuterium or both as compared to neutral pH waters found in the same systems. Isotope enrichment of both oxygen-18 and deuterium means higher percentage of magmatic vapour contribution to the well discharges due to the fact that un-neutralized magmatic water carries much abundant hydrogen ions to keep the water at a lower pH. This is consistent with the observation that acid geothermal waters usually occur near the volcanic heat source of a geothermal system, where the magmatic component tends to reach a higher percentage. 相似文献
245.
PANGLei ZHANGMing-bo ZHANGJi-xian ZHENGZhao-qing LINZong-jian 《中国地理科学(英文版)》2004,14(3):258-262
Remote sensing technique, replacing conventional sonar bathymetry technique, has become an effective complementary method of mapping submarine terrain where special conditions make the sonar technique difficult to be carried out. At the same time, as one kind of data set, multispectral remote sensing data has the disadvantage of being influenced by the variable bottom types in shallow seawater, when it is applied in bathymetry. This paper puts forward a new method to extract water depth information fi‘om multispectral data, considering the bottom classification and the true water depth accuracy. That is the Principal Component Analysis (PCA) technique based on the bottom classification. By the least square regression with significance, the experiment near Qingdao City has obtained more satisfactory bathymetry accuracy than that of the traditional single-band method, with the mean absolute error about 2.57m. 相似文献
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249.
Holocene East Asian monsoon variation inferred from species assemblage and shell chemistry of the ostracodes from Hulun Lake, Inner Mongolia 总被引:3,自引:0,他引:3
Dayou Zhai Jule Xiao Lang Zhou Ruilin Wen Zhigang Chang Xu Wang Xindi Jin Qiqing Pang Shigeru Itoh 《Quaternary Research》2011,75(3):512-522
A sediment core from Hulun Lake, Inner Mongolia was analyzed for species assemblages and shell chemistry of ostracodes to investigate changes in the hydrology and climate of the East Asian summer monsoon margin during the Holocene. Darwinula stevensoni was abundant, Ilyocypris spp. scarce, littoral ostracodes absent and Mg/Ca, Sr/Ca and δ18O were low 11,100 to 8300 yr ago, indicating high lake levels and cool/fresh waters. Darwinula stevensoni declined largely, Ilyocypris spp. throve, littoral ostracodes were rare and chemical indicators remained in low values 8300 to 6200 yr ago, suggesting that the lake continued high stands but water became warm. The lake then contracted and water became cool/brackish 6200 to 4300 yr ago. Littoral ostracodes flourished 4300 to 3350 yr ago, marking the lowest lake levels of the entire Holocene. The lake level recovered and water salinity decreased 3350 to 1900 yr ago. From 1900 to 500 yr ago, the lake maintained the preceding status albeit lowered stands and increased salinities 1100 to 800 yr ago. During the recent 500 yr, the lake expanded and water salinity decreased. The data imply that the East Asian summer monsoon did not intensify until 8300 yr ago and weakened dramatically 4300 to 3350 yr ago. 相似文献
250.
Ethnicity is a carrier of language and culture.Spatial distribution of ethnic diversity is fundamental for identifying and reconstructing the migration patterns and evolution histories of cultures and languages.Utilizing the Chinese 4th National Census (1990) data,we investigated the specific time geographical patterns of population and diversity of Chinese ethnicminorities.As anticipated,results show that Chineseminorities are chiefly concentrated in dis-tant plateaus and mountains in the southwest,northwe... 相似文献