Terrain texture analysis is an important method of digital terrain analysis in quantitative geomorphological research and in the exploration of the spatial heterogeneity and autocorrelation of terrain features. Howeve...Terrain texture analysis is an important method of digital terrain analysis in quantitative geomorphological research and in the exploration of the spatial heterogeneity and autocorrelation of terrain features. However, a major issue often neglected in previous studies is the calculation unit of the terrain texture, that is, the stability analysis unit. As the test size increases, the derived terrain textures become increasingly similar so that their differences can be ignored. The test size of terrain texture is defined as the stability analysis unit. This study randomly selected 48 areas within the Loess Plateau in northern Shaanxi in China as the study sites and used the gray level co-occurrence matrix to calculate the terrain texture. The stability analysis unit of the terrain texture was then extracted, and its spatial distribution pattern in the Loess Plateau was studiedusing spatial interpolation method. Four terrain texture metrics, i.e., homogeneity, energy, correlation, and contrast, were extracted on the basis of the stability analysis unit, and the spatial variation patterns of these parameters were studied. Results showed that the spatial distribution pattern and the terrain texture metrics reflected a trend of high–low–high from north to south, which correlated with the spatial distribution of the landforms at the Loess Plateau. In addition, the terrain texture measures was significantly correlated with the terrain factors of gully density and slope, and this relationship showed that terrain texture measures based on the stability analysis unit could reflect the basic characteristics of terrain morphology. The stability analysis unit provided a reasonable analytical scale for terrain texture analysis and could be used as a measure of the regional topography to accurately describe basic terrain characteristics.展开更多
This paper states how the reciprocal matching of foreign direct investment （FDI） and geographic location generally determine the pattern of regional economic development in China by analyzing the co-relations among ...This paper states how the reciprocal matching of foreign direct investment （FDI） and geographic location generally determine the pattern of regional economic development in China by analyzing the co-relations among geographic location, FDI and regional economic development. Among various factors that affect FDI inflow into specific regions of China, it is believed that geographic location might be one of the most essential factors in shaping the overall trend of diversification in regional economic development in China. Examinations are followed for identifying the above judgment both with econometric models and data analysis.展开更多
Based on analysis of drilling, logging and field profile data, six sequence boundaries in Permian are identified in Bachu and Tazhong regions of Tarim Basin. All sequence boundaries are of type I sequence bound- aries...Based on analysis of drilling, logging and field profile data, six sequence boundaries in Permian are identified in Bachu and Tazhong regions of Tarim Basin. All sequence boundaries are of type I sequence bound- aries, and are characterized by down cut. According to the six sequence boundaries, the Permian in this area can be divided into 5 third-order sequences, and all the sequences correspond with classic sequence model of Vail. Sequence Psq4 indicates lake transgressive system tract （TST） and highstand system tract （HST）. Se- quences Psql, Psq2, Psq3, Psq5 indicate low stand system tract （ LST）, transgressive system tract and high- stand system tract. LST is deposited by incised channel infilling with features of fluvial facies. TST is deposited by shore-shallow lake and semi-deep lake. HST is deposited by semi-deep lake, shore-shallow lake and delta. In addition, volcanic rocks are present on the top part of HST in sequence Psq3. Incised channel infilling and deltaic deposits were mainly distributed on western slope of Tadong uplift.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 41471316, 41571383, 41671389)the Priority Academic Program Development of Jiangsu Higher Education Institutions-PAPD (Grant No. 164320H101)the Key Project of Natural Science Research of Anhui Provincial Department of Education (Grant No. KJ2015A171)
文摘Terrain texture analysis is an important method of digital terrain analysis in quantitative geomorphological research and in the exploration of the spatial heterogeneity and autocorrelation of terrain features. However, a major issue often neglected in previous studies is the calculation unit of the terrain texture, that is, the stability analysis unit. As the test size increases, the derived terrain textures become increasingly similar so that their differences can be ignored. The test size of terrain texture is defined as the stability analysis unit. This study randomly selected 48 areas within the Loess Plateau in northern Shaanxi in China as the study sites and used the gray level co-occurrence matrix to calculate the terrain texture. The stability analysis unit of the terrain texture was then extracted, and its spatial distribution pattern in the Loess Plateau was studiedusing spatial interpolation method. Four terrain texture metrics, i.e., homogeneity, energy, correlation, and contrast, were extracted on the basis of the stability analysis unit, and the spatial variation patterns of these parameters were studied. Results showed that the spatial distribution pattern and the terrain texture metrics reflected a trend of high–low–high from north to south, which correlated with the spatial distribution of the landforms at the Loess Plateau. In addition, the terrain texture measures was significantly correlated with the terrain factors of gully density and slope, and this relationship showed that terrain texture measures based on the stability analysis unit could reflect the basic characteristics of terrain morphology. The stability analysis unit provided a reasonable analytical scale for terrain texture analysis and could be used as a measure of the regional topography to accurately describe basic terrain characteristics.
文摘This paper states how the reciprocal matching of foreign direct investment （FDI） and geographic location generally determine the pattern of regional economic development in China by analyzing the co-relations among geographic location, FDI and regional economic development. Among various factors that affect FDI inflow into specific regions of China, it is believed that geographic location might be one of the most essential factors in shaping the overall trend of diversification in regional economic development in China. Examinations are followed for identifying the above judgment both with econometric models and data analysis.
文摘Based on analysis of drilling, logging and field profile data, six sequence boundaries in Permian are identified in Bachu and Tazhong regions of Tarim Basin. All sequence boundaries are of type I sequence bound- aries, and are characterized by down cut. According to the six sequence boundaries, the Permian in this area can be divided into 5 third-order sequences, and all the sequences correspond with classic sequence model of Vail. Sequence Psq4 indicates lake transgressive system tract （TST） and highstand system tract （HST）. Se- quences Psql, Psq2, Psq3, Psq5 indicate low stand system tract （ LST）, transgressive system tract and high- stand system tract. LST is deposited by incised channel infilling with features of fluvial facies. TST is deposited by shore-shallow lake and semi-deep lake. HST is deposited by semi-deep lake, shore-shallow lake and delta. In addition, volcanic rocks are present on the top part of HST in sequence Psq3. Incised channel infilling and deltaic deposits were mainly distributed on western slope of Tadong uplift.
