地球学报
地毬學報
지구학보
ACTA GEOSCIENTIA SINICA
2013年
6期
757-762
,共6页
腾格里沙漠%快组分%OSL信号区间
騰格裏沙漠%快組分%OSL信號區間
등격리사막%쾌조분%OSL신호구간
Tengger desert%fast component%OSL signal intervals
光释光(OSL)信号衰减曲线不同时段信号积分的选择,直接影响到能否有效提取快组分信号,从而影响等效剂量(De)计算的准确性。本文根据腾格里沙漠南缘古浪县附近的两个剖面的6个风成沉积物的共193个单片的单片再生剂量法(SAR)测试结果,将石英OSL衰减曲线分解成快、中、慢与背景信号三个组分。利用分解出的 OSL快组分信号建立再生曲线,求取每个单片对应的 De值,并与4组选择 OSL衰减曲线上不同时段信号积分的SAR法所计算的De值对比。结果表明,腾格里沙漠南缘风成沉积物的De值对信号区间选择方式较为敏感;使用通道1~2(0~0.32 s)作为快组分信号区间,通道3~7(0.32~1.12 s)作为背景信号区间的早期背景信号扣除法获得的 De 值与快组分法计算的 De 值较一致;晚期背景信号扣除法由于受中组分信号的显著影响,计算的De值与真实De值之间存在较大差异。
光釋光(OSL)信號衰減麯線不同時段信號積分的選擇,直接影響到能否有效提取快組分信號,從而影響等效劑量(De)計算的準確性。本文根據騰格裏沙漠南緣古浪縣附近的兩箇剖麵的6箇風成沉積物的共193箇單片的單片再生劑量法(SAR)測試結果,將石英OSL衰減麯線分解成快、中、慢與揹景信號三箇組分。利用分解齣的 OSL快組分信號建立再生麯線,求取每箇單片對應的 De值,併與4組選擇 OSL衰減麯線上不同時段信號積分的SAR法所計算的De值對比。結果錶明,騰格裏沙漠南緣風成沉積物的De值對信號區間選擇方式較為敏感;使用通道1~2(0~0.32 s)作為快組分信號區間,通道3~7(0.32~1.12 s)作為揹景信號區間的早期揹景信號釦除法穫得的 De 值與快組分法計算的 De 值較一緻;晚期揹景信號釦除法由于受中組分信號的顯著影響,計算的De值與真實De值之間存在較大差異。
광석광(OSL)신호쇠감곡선불동시단신호적분적선택,직접영향도능부유효제취쾌조분신호,종이영향등효제량(De)계산적준학성。본문근거등격리사막남연고랑현부근적량개부면적6개풍성침적물적공193개단편적단편재생제량법(SAR)측시결과,장석영OSL쇠감곡선분해성쾌、중、만여배경신호삼개조분。이용분해출적 OSL쾌조분신호건립재생곡선,구취매개단편대응적 De치,병여4조선택 OSL쇠감곡선상불동시단신호적분적SAR법소계산적De치대비。결과표명,등격리사막남연풍성침적물적De치대신호구간선택방식교위민감;사용통도1~2(0~0.32 s)작위쾌조분신호구간,통도3~7(0.32~1.12 s)작위배경신호구간적조기배경신호구제법획득적 De 치여쾌조분법계산적 De 치교일치;만기배경신호구제법유우수중조분신호적현저영향,계산적De치여진실De치지간존재교대차이。
Selections of different signal intervals affect the precision of equivalent dose calculation. Six dune samples from Gulang at the southern edge of Tengger Desert were dated using optically stimulated luminescence (OSL) by employing various signal intervals, and a total of 193 aliquots were obtained. Fast-component based equivalent dose (De) analysis was performed by decomposing OSL signals to fast, middle, slow plus background signal. The comparison of SAR De values with fast-component based De values shows that De values of these samples are sensitive to selections of OSL signal intervals, that using the‘early background’ method with channel 1~2(0~0.32 s) as the interval for fast-component signal and channel 3~7(0.32~1.12 s) as the interval for background signal obtains De values that is consistent with fast-component based De values, and that significant differences exist between De values calculated using ‘late background’ method and those calculated using fast-component method, suggesting that ‘late background’ based OSL signal is affected strongly by middle component.