Background And Education
My primary professional interests include study of Cretaceous and Paleogene paleoclimate and paleoceanography, evolutionary dynamics and extinction of Cretaceous and Paleogene planktic foraminifera, and biotic and paleoenvironmental changes across mid-Cretaceous Oceanic Anoxic Events.
My research involves the study of foraminifera, especially planktonic foraminifera, and what they can tell us about how Earth’s environment has changed during the past 120 million years. Because of their small size, relatively short geologic age ranges, and wide distribution in a variety of marine sediments worldwide, study of foraminiferal assemblages provides valuable insight to the age of the sediments in which they are found (biostratigraphy), the type of environment in which they were deposited (paleoecology), and the temperature of the ocean water in which they grew (paleoclimatology and paleoceanography). Biostratigraphic analysis require species identification and calculation of sedimentation rates using age calibrations for the evolutionary appearances and extinctions of species from different fossil groups, paleomagnetic reversal events, carbon and oxygen isotopic events, and constraints using radiometric and strontium isotopic data. These are plotted on age-depth curves, which enable age assignments to all samples with age control points. Insight into paleoecologic change is gained through quantitative analysis of species assemblages through time as well as through study of shell geochemistry. Oxygen isotope analyses of well-preserved foraminiferal shells are especially useful for determination of relative paleotemperature changes of the ocean bottom (using benthic foraminifera) and the ocean surface (using planktonic foraminifera). Reconstruction of global surface and bottom water temperatures during the Cretaceous Period (145-66 million years ago) using foraminiferal oxygen isotopes through the long- and short-term climate changes, has been one of my primary research objectives. For all of my studies, accurate species identification is a necessity. This has led to my participation in several taxonomic working groups and publication of several taxonomic atlases and development on the Mikrotax online taxonomic database (http://www.mikrotax.org/pforams/index.html).