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511.
1998 Compilation of Analytical Data for Five GSJ Geochemical Reference Samples: The "Instrumental Analysis Series" 总被引:1,自引:0,他引:1
Noboru Imai Shigeru Terashima Shiro Itoh Atsushi Ando 《Geostandards and Geoanalytical Research》1999,23(2):223-250
Analytical data for five GSJ (Geological Survey of Japan) reference samples, the "Instrumental analysis series" received by October 1998, are compiled. The data reported in publications and personal communications were evaluated statistically, taking into account the analytical method and sample preparation. Based on the selected available data, recommended and preferred values for fourteen major and fifty one minor and trace elements are proposed. 相似文献
512.
513.
A Late Holocene geomagnetic secular variation record from Erhai Lake, southwest China 总被引:1,自引:0,他引:1
Masayuki Hyodo Arata Yoshihara Kenji Kashiwaya Takashi Okimura Toshiyuki Masuzawa Ryotaro Nomura Shingo Tanaka Tang Bang Xing Liu Su Qing & Liu Shi Jian 《Geophysical Journal International》1999,136(3):784-790
A secular variation record of the geomagnetic field direction for the last 6.5 kyr has been obtained from the magnetization of sediment cores from Erhai Lake, southwest China. In order to make a comparison with this record, secular variation in east-central China was investigated by combining available magnetic field data from historical records and archaeomagnetic measurements since about 350 bc . The secular variation in Erhai Lake shows features consistent with the combined record, except for the oldest three observed declination swings in Sian from 720 to 900 ad . Many features of declination and inclination in China also occur in Japan. From 500 to 1000 ad , declination was westerly ranging from about −20° to −5° in Erhai Lake, east-central China, and Japan. 相似文献
514.
Comparison of Kuroshio surface velocities derived from satellite altimeter and drifting buoy data 总被引:2,自引:0,他引:2
Sea-surface geostrophic velocities for the Kuroshio region calculated from TOPEX/POSEIDON altimetry data together within situ oceanographic data are compared with surface velocities derived from drifting buoy trajectories. The geostrophic velocities
agree well with the observed velocities, suggesting that the Kuroshio surface layer is essentially in geostrophic balance,
within measurement error. The comparison is improved a little when the centrifugal acceleration is taken into account. The
observed velocities are divided into the temporal mean and fluctuation components, and the partitioning of velocities between
these two components is examined. For the Kuroshio region, most of the fluctuation components of the velocities derived from
drifting buoys are found to be positive. This result suggests that Eulerian mean velocities for the Kuroshio region estimated
from drifting buoy data tend to be larger than actual means, due to the buoy’s tendency to sample preferentially in the high-velocity
Kuroshio. 相似文献
515.
Stemflow was evaluated in a water balance and its contribution to groundwater recharge determined. Gross precipitation, throughfall and stemflow were measured for one year in a pine forest (Tsukuba, Japan) to determine each component of the water balance in the forest. Groundwater recharge rates by stemflow and throughfall were calculated from a mass balance method using chloride in subsurface waters. The stemflow in the water balance was relatively small when estimated as a value per canopy projected area of the tree in the forest. However, the results for the mass balance of chloride in subsurface waters indicated that it was impossible to disregard the stemflow in determining groundwater recharge. Although the ratio of stemflow to the net precipitation was small in the water balance, the effect of stemflow on groundwater recharge was relatively large. 相似文献