The accurate measurement of equivalent doses is the key to the dating of debris flow samples. Using different radiation intervals measure debris flow material samples, the equivalent doses obtained are different, indicating irradiation interval impacts the equivalent dose of the debris flow material samples. Test debris flow samples used the known equivalent dose of 30 Cy, and measure them in different intervals of irradiation dosime-try. 2.5 Gy/ min β -source (90Sr-50Y) irradiation intervals were selected to 1, 2, 4, 6 min, the equivalent dose obtained respectively 19.3, 22.3, 26.4, 23.0 Gy; 8 Gy/ min of β source (90Sr-90Y) irradiation intervals were selected to0.5, 1, 1.5,2 min, the equivalent dose obtained respectively 17.6, 19.6 , 25.3, 15.6 Gy. The research indicate that he most suitable irradiation interval which by the dose rate 2.5 Gy / min of the β source (90Sr - 90Y) measure the debris flow material is 4 min. And the most suitable irradiation interval which by the dose rate 8 Gy / min of the β source (90Sr - 90Y) measure the debris flow material is 1.5 min.%等效剂量的准确测定是进行地质样品热释光年龄测定的关键.采用不同辐照间隔增量测量泥石流物质标样,测得的等效剂量值是不同的,说明辐照剂量增量对泥石流物质样品等效剂量值存在影响.测试选用已知等效剂量为30Gy的泥石流标样,按不同的辐照剂量增量进行等效剂量测定.2.5Gy/min的β源(90sr-90Y)辐照剂量增量分别选用1、2、4、6min时,测得的等效剂量分别为19.3、22.3、26.4、23.0 Gy;8 Gy/min的β源(90Sr -90Y)辐照剂量增量分别选用0.5、1、1.5、2min时,测得的等效剂量分别为17.6、19.6、25.3、15.6 Gy.研究表明:对于30Gy的泥石流标样,剂量率为2.5 Gy/s的β源(90Sr -90y)测定泥石流物质时最适合的辐照剂量增量为4 min.剂量率为8Gy/s的β源(90Sr -90Y)测定泥石流物质时最适合的辐照剂量增量为1.5 min.
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