Quantitative Method for identifying Sediment Sources from Magnetic Measurement
Yu Lizhong (Dept. of Geography, East China Normal University)
Mlneral magnetic measurements, which form the nucleus of a newly developing methodology, have proved to be of exceptional promise in many aspects of environmental study by virtue of their relative cheapness, ease of use, data-based-analysis, non-destructive nature and versatility. This study contributed a sequential method for quantitatively identifying sediment sources from magnetic measurements, which was demonstrated on the materials from Rhode River catchment, Maryland, USA. Cluster analysis on a multi-parameter basis was used for the source classification with regard to magnetic properties. Mass mixing test and multiple regression analysis were employed to establish numerical rela tionship between magnetic measurements of mixtures and their source component proportions. Based on these regression models, source compo nents of three estuarine sediment cores were estimated by linear program. The lesults strongly support the previous studies on this catchment which indicated a dramatic change in sediment source some 150 to 200 years ago. Quantitative data are more informative and useful than purely Qualitative descriptions.