Dorale JA, Edwards RL, Ito E, Gonzalez LA
J. A. Dorale, R. L. Edwards, E. Ito, Department of Geology and Geophysics, University of Minnesota, Minneapolis, MN 55455, USA. L. A. Gonzalez, Department of Geology, University of Iowa, Iowa City, IA 52242, USA.
Science. 1998 Dec 4;282(5395):1871-4. doi: 10.1126/science.282.5395.1871.
Four Missouri stalagmites yield consistent overlapping records of oxygen and carbon isotopic changes and provide a climate and vegetation history with submillennial resolution from 75 to 25 thousand years ago (ka). The thorium-230-dated records reveal that between 75 and 55 ka, the midcontinental climate oscillated on millennial time scales between cold and warm, and vegetation alternated among forest, savanna, and prairie. Temperatures were highest and prairie vegetation peaked between 59 and 55 ka. Climate cooled and forest replaced grassland at 55 ka, when global ice sheets began to build during the early part of Marine Oxygen Isotope Stage 3.
密苏里州的四个石笋产生了一致的氧和碳同位素变化重叠记录，并提供了距今75,000至25,000年前亚千年分辨率的气候和植被历史。钍-230年代测定的记录显示，在75,000至55,000年前之间，大陆中部气候在千年时间尺度上在寒冷和温暖之间振荡，植被在森林、稀树草原和草原之间交替。在59,000至55,000年前之间温度最高，草原植被达到顶峰。在55,000年前，当全球冰盖在海洋氧同位素阶段3早期开始形成时，气候变冷，森林取代了草原。
