By Tara Anthony, Penn State University Libraries Geological maps are a valuable resource for understanding characteristics of earth properties through rock and mineral formations. Historical geological maps held within map collections can span geographic areas and be useful for understanding regions across administrative regions, such as state borders. The BTAA Geoportal can be a source for identifying where to look for historic geological map collections within BTAA institutions. This blog post will highlight what types of geological maps are able to be located from the BTAA Geoportal as of Spring 2025. Geological maps are a resource type for narrowing down specific map types. See this search for Resource type (Geological maps) for results. These historic geological maps are primarily from the early half the 1900s, with some earlier geological maps as well that date back to the mid-1800s. Of the results, the following institutions have materials clas...
Exploring geospatial resources: Discover collection highlights, dive into historical map interpretations, uncover the value of unique datasets, hear from data providers, and stay updated on geospatial collection processing across BTAA institutions.