K Ar and Ar Ar dating is one of the best dating method to Mesozoic Cenozoic volcanic rocks. Appropriate size and preprocessing procedure are important for the method to get good data.

• K Ar和Ar Ar法是中、新生代火山岩最有效的测年方法之一 ,合适的粒度和有效的预处理程序对于提高年龄资料的质量至关重要。