Shanan E Peters , Jon M. Husson , John Czaplewski

Characterizing the lithology, age, and physical-chemical properties of rocks and sediments in the Earths upper crust is necessary to fully assess energy, water, and mineral resources and to address many fundamental questions in the Earth sciences. Although a large number of geological maps, regional geological syntheses, and sample-based measurements have been produced, there is no openly available database that integrates rock record-derived data while facilitating large-scale, quantitative characterization of the volume, age, and material properties of the upper crust. Here we describe Macrostrat, a relational geospatial database and supporting cyberinfrastructure that is designed to enable quantitative spatial and geochronological analyses of the entire assemblage of surface and subsurface sedimentary, igneous and metamorphic rocks. Macrostrat now contains general, comprehensive summaries of the age and properties of 33,903 lithologically and chronologically-defined geological units distributed across 1,474 regions in North and South America, the Caribbean, New Zealand, and the deep sea. Sample-derived data, including fossil occurrences in the Paleobiology Database, more than 180,000 geochemical and outcrop-derived measurements, and more than 2.1 million bedrock geologic map units from over 170 map sources, are linked to specific Macrostrat units and/or lithologies. Macrostrat has generated numerous quantitative results and its data infrastructure is being used in several independently developed mobile applications. However, it is necessary to expand geographic coverage and to refine age models and material properties to arrive at a more precise characterization of the upper crust globally.