山东章丘黄土剖面色度研究

Study on the Chroma of Zhangqiu Loess in Shandong Province

对山东章丘黑峪黄土剖面色度进行了分析测试,并尝试建立与粒度各粒级之间的相关性分析,初步得出以下结论:(1)章丘黄土剖面中的L^*值变化波动较大,变化幅度在54.26~61.57之间,平均值为59.34,不同地层的L^*值各不相同;章丘黄土剖面中的红度a^*值的变化幅度很小,介于5.87~7.35,平均值为6.75,不同地层其a^*值差异也较小;章丘黄土剖面中的黄度b^*值变化趋势与a^*相似,变化范围在14.91~17.61之间,变化幅度较大,平均值为17.03.(2)章丘黄土剖面中的a^*/b^*值的变化趋势与L^*呈现相反的变化,变化范围为0.36~0.40,变化幅度较大,平均值为0.40,a^*/b^*比值的分布趋势在不同深度上变化不明显平均值为0.41.(3)在粒度各粒级之中,色度参数与小于5μm粒级的沉积物具有正相关关系.L^*与a^*的相关系数R为-0.407,呈负相关关系,表明L^*值随着a^*值的增大而减小;L^*与b^*的相关系数R为0.481,呈正相关关系,二者的变化趋势保持基本一致,说明在一定程度上L^*值随着b^*值的变化而变化;L^*与a^*/b^*的相关系数R为-0.756,呈显著的负相关关系,表现出L^*值随着a^*/b^*值增大而减小的关系.

Loess chroma,as a good climate substitute index,has been widely used in the study of indicative climate significance.By analyzing the chroma parameters of Zhangqiu loess section and trying to establish the correlation analysis with the grain size,the following conclusions are drawn:(1)The variation of L^* value in Zhangqiu loess section fluctuates greatly,ranging from 54.26 to 61.57,with an average value of 59.34,and the L^* values of different strata are different;the variation of red a^* value in Zhangqiu loess section tends to be stable as a whole,and the variation range is very large.It is small,ranging from 5.87 to 7.35,with an average value of 6.75,and the difference of a^* value among different strata is small.The variation trend of b^* value of yellowness in Zhangqiu loess profile is similar to that of a^* with a variation range of 14.91 to 17.61,with a larger variation range,with an average value of 17.03.(2)The change trend of a^*/b^* value in Zhangqiu loess section is opposite to that of L^*,ranging from 0.36 to 0.40.The change range is large,with an average value of 0.40.The distribution trend of a^*/b^* value is not obvious in different depths.The highest value appears in the loess layer below the gravel layer G2,with an average value of 0.41.(3)Among the grain sizes,there is a positive correlation between the chroma parameters and sediments with a grain size of less than 5 um.The correlation coefficient R between L^* and a^* is -0.407,showing a negative correlation,indicating that the value of L^* decreases with the increase of a^* value;the correlation coefficient R between L^* and b^* is 0.481,showing a positive correlation.The change trend of both is basically the same,indicating that the value of L^* changes with the change of b^* value to a certain extent;the correlation coefficient R between L^* and a^*/b^* is -0.756,showing the relationship of L^* value decreasing with the increase of a^*/b^*.