【摘要】 当前通用的自然伽马测井方法无法区分总伽马计数中 U、Th、K各自的贡献。当地层中含有钍矿物 (如锆石英、独居石、褐帘石 )、钾长石及钾矿时 ,2 3 2 Th、4 0 K同位素对伽马计数的贡献不可忽略。文中通过实例强调了伽马能谱测井的必要性。在今后 ,建议能谱测井应与其它测井方法配合使用更多还原

【Abstract】 The present natural gamma ray log fails to ascertain the respective contributions of U, Th and K elements to the total gamma values. When there exist thorium minerals (zircon sand, turnerite, tautolite), potash feldspar and potassium ore, the contributions of - 232 Th and - 40K isotopes to total gamma values are not negligible. Real exam ples prove the necessity of gamma spectrometry log. It should be used together w ith other log methods in the days to come.更多还原