Nature and timing of long-term landscape evolution by optical dating of single grains of sand

我们正在申请资金，用于购买Risø双激光单粒光激发发光（OSL）装置，以及配套的硬件和软件，该装置旨在直接适合我（Lian）现有的Risø型号TL/ ols - da -20测年系统。升级将使现有系统现代化，显著提高其实用性，并将其寿命延长十年；它还允许从制造商那里无缝添加其他组件。双激光单粒OSL连接将使我们能够在单粒水平（光学测年中最小的基本分析单位）上仔细检查石英和钾长石沉积物样品的发光信号，这反过来又将使我们能够显着提高光学年龄测定的精度和准确性。这是通过在不同年龄群体的样品中识别和分离颗粒（石英和钾长石）来实现的，通过检测和避免具有可能对计算年龄产生负面影响的恶性发光特性的颗粒（石英）来实现的，或者通过识别和只包括那些具有发光特性的颗粒来计算更古老的年龄（所谓的“超级颗粒”）。单粒分析将使我们更好地理解，也许更有效地规避，钾长石和其他长石矿物异常褪色的有害影响。

We are requesting funding for the purchase of a Risø dual-laser single-grain optically-stimulated luminescence (OSL) unit, and supporting hardware and software, that is designed to fit directly onto my (Lian’s) existing Risø model TL/OSL-DA-20 dating system. The upgrade will modernize the existing system, significantly increase its usefulness, and extend its life for another decade; it will also allow for the seamless addition of other components available from the manufacturer. The dual-laser single-grain OSL attachment will allow us to scrutinize the luminescence signals from quartz and K-feldspar sediment samples at the single grain level (the smallest fundamental unit of analysis in optical dating) which will, in turn, allow us to significantly increase the precision and accuracy of optical ages determined from them. This is accomplished by identifying and separating grains (quartz and K-feldspar) in a sample with different age populations, and by detecting and avoiding grains (quartz) with malign luminescence properties that can negatively effect calculated ages, or by identifying and including only those grains with luminescence properties that allow for much older ages to be calculated (so-called ‘super grains’). Single grain analysis will allow us to better understand, and perhaps more effectively circumvent, the malign effect of anomalous fading in K-feldspar and other feldspar minerals.