VENT PROCESSES AND DEPOSITS OF A HIATUS IN A VIOLENT ERUPTION: QUILOTOA VOLCANO, ECUADOR By Joanne A. Best A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in Geology Northern Arizona University December 2010 Approved: __________________________________ Michael Ort, Ph.D., Chair __________________________________ Katharine V. Cashman, Ph.D. __________________________________ Nancy Riggs, Ph.D.