六十年代以来,世界各大洲前寒武纪地盾出露区均发现了老于30亿年的外地壳岩石。鞍山地区鞍山群的等时线年龄证明,我国也确实存在老于30亿年的外地壳岩石,只是迄今未见公开报道。现将早太古代鞍山群分析原始数据列如下表: 以Pb“。”/PbZ“啥为横坐标,以Pb”。了/PbZ“’为纵坐标作图,获得一线性程度较好的 Since the 1960s, crustal rocks older than 3.0 billion years have been discovered in Precambrian shield outcrops on all continents. The isochron age of Anshan Group in Anshan area proves that there are indeed some 3 billion years of crustal rocks in the outer region of China that have not been reported yet. As early as the ancient Anshan group analysis of the original data as follows: Pb ”. “ / PbZ ”What is abscissa to Pb “. / PbZ ”for the vertical coordinate mapping, get a better degree of linearity