The results show that the contents of thorium, uranium and potassium in shallow parts increase with the enhanced degrees of oil exploration and developments, and their contents in the Yellow River delta are lower than the mean richness in the crust.

• 将所采集的数据与地壳中钍、铀、钾元素含量的平均值进行比较，得出黄河三角洲地区的钍、铀、钾元素含量普遍较低的结论。