Science. 1970 Oct 9;170(3954):161-2. doi: 10.1126/science.170.3954.161.
Crystalline rocks from Mare Tranquillitatis have yielded potassium-argon dates as old as 3.8 x 10(9) years. Crystalline rocks from Oceanus Procellarum give potassium-argon ages as old as 2.8 x 10(9) years. Evidently the maria are ancient features of the moon and were not formed contemporaneously, a conclusion that also has been verified by other methods. The potassium-argon ages of rocks from Oceanus Procellarum show much more loss of argon than the rocks from Mare Tranquillitatis, an indication that the rocks at Oceanus Procellarum have experienced more severe shock effects or longer cooling rates.
月海玄武岩的钾氩测年结果表明其年龄高达 38 亿年。风暴洋玄武岩的钾氩测年结果表明其年龄高达 28 亿年。显然，月海是月球古老的地貌特征，并非同时形成的，这一结论也已经被其他方法验证。风暴洋岩石的钾氩测年结果显示出比月海岩石更多的氩气损失，这表明风暴洋的岩石经历了更强烈的冲击效应或更长的冷却速率。
