Using over 3 500 first P arrival times recorded by nine digital seismic stations from Hainan Digital Seismic Net-work during 1999～2005,a 3-D P-wave velocity model of the crust under Hainan Island and adjacent regions...Using over 3 500 first P arrival times recorded by nine digital seismic stations from Hainan Digital Seismic Net-work during 1999～2005,a 3-D P-wave velocity model of the crust under Hainan Island and adjacent regions has been determined. The results show that the pattern of velocity anomalies in the shallower upper crust is somewhat associated with the surface geological tectonics in the region. A relative low-velocity anomaly appears north of the Wangwu-Wenjiao fault zone and a relative high-velocity anomaly appears south of the Wangwu-Wenjiao fault zone,corresponding to the depressed areas in north Hainan Island,where many volcanoes are frequently active and geothermal values are relatively higher,and the uplifted and stable regions in central and south of the Hainan Is-land. In the middle and lower crust velocities are relatively lower in east Hainan than those in west Hainan,possi-bly suggesting the existence of the upwelling of hot materials from the mantle in east Hainan. The pattern of veloc-ity anomalies also indicates that NW faults,i.e.,the Puqian-Qinglan fault,may be shallower,while the E-W Wangwu-Wenjiao fault may be deeper,which perhaps extends down to Moho depth or deeper.展开更多
Diversity indices and abundance distribution models are statistical tools which ecologists have applied for decades for analyzing the intrinsic regularities of various ecological entities. In ...Diversity indices and abundance distribution models are statistical tools which ecologists have applied for decades for analyzing the intrinsic regularities of various ecological entities. In this work, we have applied these techniques to use the notions such as pedodiversity (as an example of geodiversity in a broad sense), in order to detect the differences and similarities between both natural resources, biological and non-biological. The discussion has mainly been conducted through the study of landform based pedodiversity analysis applied to SOTER digital databases in Hainan Island, China. The main analytical methods include indices of richness S that are the number of the categories (SOTER units relating to different soils in this work), indices based on proportional abundance of categories H' and E which are not only the number but also their relative abundance (in our case, the relative area occupied by each pedotaxa) is taken into account, models of the distribution of abundance of categories that provide the most complete description but also the least abridged and GIS mapping to show the spatial variation digitally.展开更多
基金The special project of Detection of Haikou City Earthquake Active Faults from the Tenth Five-year Plan of China Earthquake Administration (0106512)Joint Seismological Science Foundation of China (105086)CAS Key Laboratory of Marginal Sea Geology (MSGL0503).
文摘Using over 3 500 first P arrival times recorded by nine digital seismic stations from Hainan Digital Seismic Net-work during 1999～2005,a 3-D P-wave velocity model of the crust under Hainan Island and adjacent regions has been determined. The results show that the pattern of velocity anomalies in the shallower upper crust is somewhat associated with the surface geological tectonics in the region. A relative low-velocity anomaly appears north of the Wangwu-Wenjiao fault zone and a relative high-velocity anomaly appears south of the Wangwu-Wenjiao fault zone,corresponding to the depressed areas in north Hainan Island,where many volcanoes are frequently active and geothermal values are relatively higher,and the uplifted and stable regions in central and south of the Hainan Is-land. In the middle and lower crust velocities are relatively lower in east Hainan than those in west Hainan,possi-bly suggesting the existence of the upwelling of hot materials from the mantle in east Hainan. The pattern of veloc-ity anomalies also indicates that NW faults,i.e.,the Puqian-Qinglan fault,may be shallower,while the E-W Wangwu-Wenjiao fault may be deeper,which perhaps extends down to Moho depth or deeper.
文摘Diversity indices and abundance distribution models are statistical tools which ecologists have applied for decades for analyzing the intrinsic regularities of various ecological entities. In this work, we have applied these techniques to use the notions such as pedodiversity (as an example of geodiversity in a broad sense), in order to detect the differences and similarities between both natural resources, biological and non-biological. The discussion has mainly been conducted through the study of landform based pedodiversity analysis applied to SOTER digital databases in Hainan Island, China. The main analytical methods include indices of richness S that are the number of the categories (SOTER units relating to different soils in this work), indices based on proportional abundance of categories H' and E which are not only the number but also their relative abundance (in our case, the relative area occupied by each pedotaxa) is taken into account, models of the distribution of abundance of categories that provide the most complete description but also the least abridged and GIS mapping to show the spatial variation digitally.
