Combined IRSL-OSL single aliquot regeneration (SAR) equivalent dose (De) estimates from source proximal Chinese loess
Combined IRSL-OSL single aliquot regeneration (SAR) equivalent dose (De) estimates from source proximal Chinese loess
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DOI：
10.1016/s0277-3791(03)00044-1
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发表时间：
2003-05
影响因子：
4
通讯作者：
S. Stokes;R. Hetzel;R. Bailey;Tao Mingxin
中科院分区：
文献类型：
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作者：
S. Stokes;R. Hetzel;R. Bailey;Tao Mingxin
构造-沉积体系在西藏东北部和其他地方很容易识别，但它们很难通过传统的绝对定年技术来确定年代。在祁连山，由于阶地覆盖黄土沉积物的存在，宇宙成因方法的应用变得复杂。我们选择探索应用光学测年技术直接测定黄土覆盖层沉积物的年龄，以提供阶地废弃事件的最小年龄的潜力。我们把重点放在一套六个黄土覆盖的阶地切割成一个废弃的冲积扇序列，这是由张掖逆冲断层，黑河以东的出口处从祁连山逆冲断层抬升。单等分再生（SAR）光学测年技术的应用提供了阶地年龄年表。我们采用了一种“双SAR”方法，其中等分试样受到红外（λin= 830 nm）和蓝光（λin= 470 nm）的刺激，产生两组确定性，并假设主要分别与长石和石英细粒种群有关。我们的Deand年龄测定是地层上的合理，我们没有观察到一个显着的差异，IRSL和OSL的Deestimates，在以前的研究中的情况。
Tectono-sedimentary systems are readily recognized in Northeastern Tibet and elsewhere but they have proved difficult to date via conventional absolute dating techniques. In the Qilian Shan the application of cosmogenic methods is complicated by the presence of terrace blanketing loess deposits. We have chosen to explore the potential of applying optical dating techniques to directly date the loess cover deposits to provide minimum ages for terrace abandonment events. We focussed on a suite of six loess-mantled terraces cut into an abandoned alluvial fan sequence which was uplifted by thrust faulting on the Zhangye Thrust Fault, East of the Hei He river at its exit from the Qilian Shan. Application of single aliquot regeneration (SAR) optical dating techniques provides a chronology of terrace age. We employ a ‘Double-SAR’ procedure in which aliquots are subjected to both infrared (λin=830nm) and blue (λin=470nm) stimulation and two sets of Dedeterminations are produced and assumed to relate predominantly to feldspathic and quartz fine grain populations respectively. Our Deand age determinations are stratigraphically sensible and we do not observe a significant difference between IRSL and OSL Deestimates which has been the case in previous studies.