Caitlin Graber '05 and Yim Ling Cheng '07 jointly presented a paper titled “Analysis of tree rings by ion chromatography for chemical evidence of volcanic activity” at PittCon in Orlando, Fla. PittCon is the largest international conference for analytical chemists and is attended by about 20,000 scientists from all over the world. Cheng and Graber analyzed tree rings to explore the chemical signatures that resulted from the 1980 eruption of Mount St. Helens. Their work is part of a larger on-going project to understand the chemistry of wood that was growing during the volcanic eruption on the Greek island of Thera in 1600 BC.