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721.
In-situ data from cruises in the Pearl River estuary and adjacent marine areas were collected during March to May 2001. The absorption coefficients of the water color components were studied in detail containing total suspended matter (TSM), chlorophyll-a (chl-a), colored dissolved organic matter (CDOM), and de-pigment particles. For absorption coefficient of TSM, ap, and that of de-pigment particles, ad, correlations of ap(440)-TSM, ad(440)-TSM, ap(440)-chl-a and ad-chl-a were done (the italicized term means the concentration). There was a good correlation between ap(440) and chl-a concentration. An empirical relationship model between aph(675) and chl-a was developed showing a strong correlation of 0.93. Based on the two models the chl-a and aph(λ) were correlated. The values of calculated empirical spectral slope for CDOM absorption coefficients and that of de-pigment particles, 0.017 0 and 0.011 6 respectively, both are within a relative standard error of 10.0%. 相似文献
722.
超压释放及其对油气运移和聚集的意义 总被引:22,自引:5,他引:22
从增压作用和减压作用相互关系的角度,探讨了超压释放的定义-超压趋向于静水压力降低的作用,根据超压释放的结果,超压释放可分为不完全释压和完全释压,依突破压力封闭的动力,超压释放可分为主动释压和被动释压。有两类不同的成因的超压释放通道,分别是自振通道和它拓普通,超压释放的主要机制有断裂活动,水力压裂,底辟作用,渗透性岩层输导作用,渗透作用,剥蚀作用和人为作用。超压释放提供了油气运移的现实动力,开拓了油气运移的通道,促进了生烃作用,有利于超压系统内的油气成藏,影响油气的分布。超压释放分析为探讨超压与油气的运聚提供了有效的方法。 相似文献
723.
724.
毒砂是老柞山金矿主要载金矿物。早期与晚期成矿作用形成的毒砂 ,其热电性具明显差异 :早期毒砂热电系数为正值 ,平均 2 5 0 .3μV /℃ ,P型导电 ;晚期毒砂热电系数为负值 ,平均- 2 16 .9μV /℃ ,为N型导电。通过对不同成矿期以及同一样品中不同导型毒砂的热电性特征与成分关系的研究得出 :毒砂的热电性特征由As、S相对含量决定 ,若为富As型毒砂 ,则为P型导电 ,若为富S型毒砂 ,则为N型导电。 相似文献
725.
Discussiononuncertainties,attenuationofground motionandaseismicdesigncriterionTian-ZhongZHANG(张天中);Yun-ShengMA(马云生)andXiSHU(舒... 相似文献
726.
Physico—Mechanical Property Changes Associated with mineral Phase Transition in Granite 总被引:1,自引:0,他引:1
席道瑛 《中国地球化学学报》1995,14(3):250-255
Variations in elastic wave velocity, low-frequency internal friction and acous-tic emission in granite were experimentally studied as a function of temperature.It is found that the wave velocity and Young‘s modulus tend to decrease with temperature.In association with the α-β transition of quartz a sharp internal friction peak can be recognized accompanied by a drastic drop in wave velocity and modulus and by a second peak of acoustic emission rate. 相似文献
727.
728.
MSRT的太阳观测能力 总被引:2,自引:0,他引:2
密云米波综合孔径射电望远镜( MSRT) 是一架同时具有高空间分辨率和高时间分辨率,高灵敏度的大型设备,工作频率在232 MHz。使用该望远镜能得到太阳爆发的空间分布及其随时间变化的丰富信息,所得数据将填补我国具有空间分辨率的太阳射电数据的空白。在国际太阳活动监测中,由于地理位置原因,也是其它同类设备不可取代的。可以期待在第23 周太阳峰年的观测与研究中,得到新的有意义的数据和研究成果 相似文献
729.
本文通过江苏省地震宣传工作的效果分析,说明在地方地震系统实行宣传工作目标管理的必要性和可能性。进行宣传工作的探索与研究,促进了宣传工作的发展,增强了社会公众抗御地震的力,其社会效益是显著的。 相似文献
730.
In this paper, the methods of pattern recognition and fuzzy cluster are applied to estimate comprehensive whether there would
be an earthquake which magnitude is commensurate with (N=M
0±0.3) or greatM>M
0) thanM
0 within 3 months using sequential data in 3 days immediately after a moderate or strong earthquake (M
0≥4.7) occurred, The result of retrospective test indicates that the comprehensive judgment effects by using these applied
mathematics methods are better than that of using every individual method obviously. TheV mark value of algorithm CORA-3 in pattern recognition is the highest among them. There are 44 known earthquake sequence data
(5 type- I and 39 type- II) used to learn and train, the results of internal coincidence test show that all 44 sequence samples
could be distinguished correctly. Extrapolation test by using other 4 known earthquake sequences (2 type- I and 2 type- II)
shows that all 4 extrapolation samples could be distinguished correctly also. In the process of study, these methods have
been applied to judge the post-earthquake tendency of 2 moderate earthquakes occurred recently, one is distinguished correctly
and the other wrong. The algorithm Hamming in pattern recognition and fuzzy cluster method have been applied to judge the
early post-earthquake tendency after a moderate or strong earthquake, too. TheV mark values of internal coincidence tests could get above 0.8 most cases of extrapolating are correct.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 15–21, 1993. 相似文献