The Extent of Early Versus Late Wisconsin Glaciation: A Test Using Cosmogenic 36C1 Dating

宇宙成因的氯-36累积测年法是一种新的 地质年代学方法，测量岩石已经存在了多长时间 在地球表面暴露于宇宙射线，而不是 它已经成为一个地球化学封闭系统。 述的方法 因此，可以用来确定地貌的建造日期， 冰川冰碛，很难或不可能用 常规方法。 该奖项支持冰川年代学 通过四个地点的宇宙成因36 Cl积累进行的调查（1） 对莫纳克亚山样品的测量，（2）风河山脉， 怀俄明州，（3）西北地区班克斯岛。加拿大，以及（4）另一个研究中心， 高北极 这些地点将提供一个纬度样带 来测试北方半球 以前在夏威夷和内华达州山脉观察到的模式是 由于巧合的局部异常或真正的全球气候 方面的影响. 阳性结果的一个潜在含义是 大陆规模的冰盖的增长可能更像是 对内部动力学的响应比全球气候强迫更大。

Cosmogenic chlorine-36 buildup dating is a new geochronological method that measures how long a rock has been exposed to cosmic rays on the earth's surface, rather than the time since it became a geochemically closed system. The method can thus be used to date the construction of landforms, such as glacial moraines, that are difficult or impossible to date using conventional methods. This award supports glacial chronology investigations by cosmogenic 36Cl buildup at four locations (1) measurements on samples from Mauna Kea, (2) the Wind River Range, Wyoming, (3) Banks Island, NWT. Canada, and (4) one other site in the High Arctic. These sites will provide a latitudinal transect of the northern hemisphere to test whether the chronological pattern previously observed at Hawaii and the Sierra Nevada was due to coincidental local anomalies or to truly global climate effects. One potential implication of a positive result would be that the growth of continental-scale ice caps may be more a response to internal dynamics than global climate forcing.