Melissa Hendrickson – 2006 Wilson Memorial Scholarship

MelissaHendrickson06Biography and MS Research Topic: Melissa Hendrickson graduated with her masters from the Geoscience Department at Western Kentucky University in December of 2006. After spending the spring in Mexico working on a survey and documentation project of cenotes and dry caves on the Yucatan Penninsula, she moved to London, Ontario. Melissa is currently working on her doctorate in the Geography Department at the University of Western Ontario where she is looking at borehole methods for the characterization and modeling of karst aquifers. Her quest for karst located under previously glaciated terrain has finally brought her back north to the till covered carbonate aquifers of Southwest Ontario. An avid caver, she is planning another research and exploration trip back to Southeast Alaska in the near future.

Thesis Title:  Hendrickson, M.R., 2006. The influence of organic acid on limestone dissolution: Tongass National Forest, Alaska. MS thesis, Western Kentucky University, Bowling Green, Kentucky.

Thesis Abstract:The dissolution kinetics of limestone have been studied in depth in laboratory settings and under some situations in the field. However, little has been studied about how organic acids affect the dissolution of limestone. In accordance with the Tongass Land Management Plan, one of the research priorities for National Forest is to define a relationship between peatlands and karst development. The Tongass National Forest is underlain by extensive areas of carbonate bedrock, including extensive areas of the northern portion of Prince of Wales Island. The peatlands in the Tongass drain acidic waters into the karst. It was found that the carbonate karst system acts as a buffer for the highly acidic muskeg waters. Over the gradient of the karst system for this study, the pH increases from an average of 3.89 to 7.22 and the predicted dissolution rates drop from the insurgence to the resurgence. These rates were also correlated with a mineral weight loss experiment that was in agreement with these predicted rates. The potential for dissolution from the muskeg waters is the highest recorded for a natural karst system.