ASSEMBLING CALIFORNIA'S MARINE BIODIVERSITY: A NEW MICROFOSSIL DATA RESOURCE FOR THE CRETACEOUS-PLEISTOCENE OF CALIFORNIA

The northeastern Pacific margin is a classic system for the study of marine ecosystem assembly, yet no single data resource captures this rich record. Some published marine invertebrate records have been entered into the Paleobiology Database, and there is an ongoing effort to digitize eastern Pacific marine invertebrate records from museum collections (i.e., the Eastern Pacific Invertebrate Cenozoic Communities, or EPICC, project). Yet despite their critical importance for paleoenvironmental reconstruction, paleoecology, and geochronology, there has been no comparable effort focused on the northeastern Pacific microfossil record. The paucity of publicly-available data is not for lack of sampling effort; due to the utility of marine microfossils for oil exploration, this record has been studied extensively by industry specialists. Here we present a database for the Cretaceous-Pleistocene of California, assembled from industry records that includes microfossil data from more than 500 wells and outcrops. This database comprises more than 195,000 occurrences representing over 900 unique microfossil genera in 8 major, ecologically diverse groups, including foraminifera, radiolaria, nannoplankton, ostracods, mollusks, and fish. This database provides new opportunities for analyzing the development of marine microfossil assemblages during a dynamic interval that includes several major climate transitions, the onset of sustained upwelling, and the flooding and draining of epeiric seaways. To demonstrate its utility for interdisciplinary research, we will present preliminary analyses documenting the distribution of taxa in time and space, and will integrate published data to assess the broad macroevolutionary and macroecological patterns present among the California assemblages represented. We will outline promising research avenues that utilize and build on this publicly-available database to strengthen our present understanding of the evolutionary and ecological history of California's marine fauna.