^<40>Ar-^<39>Ar法による火山岩類の年代測定 : 地球科学への応用  [in Japanese] Age determinations of volcanic materials by the ^<40>Ar-^<39>Ar method : Applications to earth sciences  [in Japanese]

The ^<40>Ar-^<39>Ar dating technique has been successfully used for many kind of rocks and minerals. Since it can give a criterion to evaluate the reliability of an obtained age by itself if stepwise heating is applied, the ^<40>Ar-^<39>Ar method is among the most important when we can get only one kind of sample at a site. The method can be applied for samples of ages ranging from Quaternary up to 4.6 Ma if appropriate samples are used. In this paper, some examples of the ^<40>Ar-^<39>Ar datings for lunar rocks, submarine volcanic rocks and Quaternary volcanic rocks are briefly reviewed. Furthermore, age studies of each grain by using this method together with a laser probe are also referred.