Geoenvironmental assessment wsing geocemical map

从爱知县北方到岐阜县南部的河流沉积物进行了研究，以评估该地区的地质环境。分析了1100个新样品中Al、Ca、Ce、Co、Cr、Cu、Fe、K、Mn、Mg、Na、Ni、P、Sr、Ti、V、Zn等17种元素。采用电感耦合等离子体原子发射光谱法和原子吸收光谱法进行分析。通过从同一地点重复或三次取样以及通过重复分析来检查取样地点的分析数据的代表性。数据显示Ti丰度的变化为±50%，其他元素的变化为±30%或更少。这种变化可能是由于含钛小副矿物的不均匀分布造成的。元素丰度变化超过10倍，在检查区。由此得到的地球化学图为。对指示元素的区域变化有意义。花岗岩出露区水系沉积物中Al、Ca、Na、K、Sr富集，而第三系沉积物占优势区水系沉积物中Co、Cr、Fe、Ni、V、Mn、Zn富集。Ca-Na-Sr-Al、P-Cu-Zn、Ti-Ce丰度之间的相关系数均大于0.6。第三纪沉积区的样品的系数明显高于花岗岩区的样品。虽然有一个样品的Cr丰度很高（785 ppm），是第三纪沉积物平均丰度的20倍，但没有发现人为污染的明显证据。结果将在短时间内公布。

Stream sediments from the northern parts of Aichi Prefecture through the southern parts of Gifu Prefecture were examined for geoenvironmental assessment of the area. New 1100 samples were analyzed for seventeen elements includingAl, Ca, Ce, Co, Cr, Cu, Fe, K, Mn, Mg, Na, Ni, P. Sr, Ti, V and Zn. ICP-AES andAAwere employed for analyzes. The representativeness of the analyzed data for the sampling locality is examined by means of duplicate or triplicate samplings from the same place and by repeated analyzes. The data show ±50% variations in the abundance of Ti and ±30% or less variations for other elements. This variation may have been caused by heterogeneous distribution of small accessory minerals bearing Ti. The elemental abundances vary more than ten times in the examined area. Then the geochemical map obtained here is . Significant to indicate the areal variations of elements. The stream sediments from the area where granitic rockare exposed are rich inAl, Ca, Na, K, and Sr. On the contrary, Co, Cr, Fe, Ni, V, Mn and Zn are enriched in the sediments from the area where the Tertiary sediments are dominant Correlation coefficients higher than 0.6 are found between abundances of Ca-Na-Sr-Al, P-Cu-Zn and Ti-Ce. The coefficients are remarkably higher for the samples from the area of the Tertiary sediments than for the samples from granitic region. Although one sample shows a high Cr-abundance (785ppm), which is 20 times the abundance of the average value for the Tertiary sediments, no clear evidence for artificial pollution of any elements examined here is found. Twenty additional elements including As and Sb are analyzed by INAA and XRF. The results will be published in a shorttime.