New maps of global geological provinces and tectonic plates

Abstract

Accurate spatial models of tectonic plates and geological terranes are important for analyzing and interpreting a wide variety of geoscientific data and developing compositional and physical models of the lithosphere. We present a global compilation of active plate boundaries and geological provinces in a shapefile format with interpretive attributes (e.g., crust type, plate type, province type, last orogeny). The initial plate and province boundaries are constructed from a combination of published global and regional models that we refine using a variety of geoscientific constraints including, but not limited to, relative GPS motions, earthquakes, mapped faults, potential field characteristics, and geochronology. These new plate model show improved correlation to observed earthquake and volcano occurrences within deformation zones and microplates, compared to existing models, capturing 73 and 80% of these criteria, respectively. Deformation zones and microplates only account for 16% of Earth’s surface area. We estimate 57.5% of the Earth’s surface is covered by oceanic crust, which is a slight increase relative to the most recent seafloor age model. The model of last orogenies agrees well with peaks in the globally summed geochronology data. There is room for improvement in future editions of our global plate and geologic provinces model where basins, ice, or lack of geological data fidelity obscure bedrock geology, particularly in the eastern Central Asian Orogenic Belt, much of Africa, East Antarctica, and eastern Australia. Additionally, some province types—orogens, shields, and cratons that are homogenized within our global scheme—can likely be partitioned into smaller terranes with more precise geodynamic attributes. Despite some of these shortcomings, the digital maps presented here form a self-consistent data standard for adding spatial metadata to geoscientific databases. The database is available on GitHub where the geoscience community can provide updates to improve the models and their contemporaneity as new knowledge is acquired. The files are also released in formats suitable for use in Generic Mapping Tools and GoogleEarth.