Citation by Andrew H. Knoll, Harvard University
Jessica Creveling is a geologist for the 21st century. Tireless in the field, meticulous and innovative in the laboratory, she addresses fundamental questions of Earth history that range from geobiology to geophysics. In early research, JC asked what environmental circumstances delimited the major Ediacaran-Cambrian interval of sedimentary phosphate deposition. Combining field research, petrology and geochemical analysis, she was able to provide an improved understanding of environmental conditions during the early diversification of animals, while addressing the paleobiological question of what factors opened and closed the window of exceptional phosphate preservation that played such a large role in recording early animal evolution.
At the same time, JC became intrigued by hypotheses for true polar wander, developing a state-of-the-art geophysical model of Earth’s rotational stability and using this to identify factors that might favor true polar wander during supercontinent assembly. And she became the first person to bring the full machinery of sea level physics to bear on deep time glacial events. JC’s epiphany was to realize that the physics of sea level change articulated for Pleistocene glaciation should also apply to more ancient events in Earth history, where eustasy has been the prevailing assumption for a half century. In her two-pronged approach to the problem, JC articulated a compelling geophysical model for post-Marinoan sea level change while demonstrating through careful field work in Death Valley that lithofacies variation in post-glacial cap carbonates implies a sea level history more complex than that expected from eustasy alone. Recent research also includes insightful analysis of the late Ordovician ice age, demonstrating through numerical modeling that “glacial isostatic adjustment can preclude synchronous and similar magnitude (or directional) changes in Late Ordovician sea level between ice proximal and ice distal locations and, hence, distort a globally correlative sequence stratigraphy.”
Always exploring new ideas, JC is currently developing and applying a powerful numerical method for objectively and quantitatively comparing chemostratigraphic correlations of stratigraphic successions, work that promises to place such correlations on more rigorous statistical footing.
What is truly remarkable about JC is the diversity of her scientific toolkit; she is at home in the field, adept at geochemical analysis, and accomplished in geophysical modeling. By combining these various approaches, she illustrates the rich possibilities of multidisciplinary research in an integrative age. Jessica Creveling represents Geology at its best.
Response by Jessica Creveling
I am deeply honored to receive recognition from GSA and for the rare opportunity to publicly convey gratitude to numerous, generous mentors. I thank Dr. and Mrs. Donath for endowing this Award.
Sam Bowring advised me to become a geoscientist familiar with the questions and methods of a secondary discipline, and these words direct my career. Andy Knoll, Paul Myrow and John Grotzinger taught me how to attribute observation to process across spatial scales. Andy graciously taught me to read and write as a professional; he modeled statesmanship. While I have much room to grow toward their collective expertise—and I lean on my peers Kristin Bergmann and Justin Strauss to do so—I thank these three for exposing me to the pinnacle of our profession.
Jerry Mitrovica’s mentorship allowed me to realize Sam’s advice. Jerry has profoundly impacted my growth as a human and as a quantitative geoscientist. Collaborating with Jerry is my greatest professional joy.
I thank my Oregon State colleagues, especially Andrew Meigs; Victoria Orphan, Maureen Raymo, and David Evans for their advocacy; David Johnston and David Fike; and my graduate students, Cedric and Meghan, for propelling our research forward. I thank my husband, Frank Sousa, an exceptional geologist, for his unconditional love.