Dr. Dorothy Z. Oehler is a planetary geologist and Precambrian paleontologist at Johnson Space Center (JSC). She is mainly interested in seeking ways to identify biosignatures of potential extraterrestrial life. This includes two lines of research: 1) establishing new criteria for identifying bona fide biosignatures of fragmentary remains of primitive life forms, and 2) using facies prediction on Mars to prioritize habitable sites that may preserve remnants of potential life on Early Mars. For biosignature criteria, Dr. Oehler has been among the first to utilize NanoSIMS for chemical mapping of some of Earth's earliest life forms. For Mars habitability, she has been using a geologic approach involving establishing regional context and predicting facies, using ArcGIS and spatial analysis of orbital datasets.