Geological data are the foundation for scientific research, natural resource assessment, engineering surveys, and risk management. Traditionally, geological materials were stored in paper archives, but digital technologies have taken over here as well. Databases and state geological collections allow for the retrieval of spatial data, maps, reports, and metadata without the need to physically visit archives. This makes them indispensable for professional geologists, students, research organizations, and territorial planners.

Key Geological Data Sources

OneGeology 

An international online portal that brings together digital geological maps from many countries worldwide.

The portal provides access to maps and mapping services via OGC standards (WMS/WFS), simplifying integration with GIS systems. It is focused on data exchange between national geological surveys and provides free access to many geological layers and cartographic data.

USGS National Geologic Map Database

The largest digital collection of geological maps and publications from the United States Geological Survey (USGS). 

The database contains tens of thousands of maps, reports, and related materials, available for free viewing and download. It covers a wide range of geological topics, from lithology and stratigraphy to natural resource information.

USGS Geospatial Data

Offers geospatial datasets, including digital elevation models, topographic layers, hydrography, mineral data, and natural hazards. These datasets are supplied in standard GIS formats (GeoTIFF, Shapefile) and are used for visualization and analysis in a GIS environment.

BRGM InfoTerre (France)

The web portal of the French Geological Survey (BRGM)

It provides free access to geological data, including digital geological maps, subsurface databases, hazard maps, and groundwater maps. Users can view maps, download data, and integrate them with other systems via standardized web services.

BGS OpenGeoscience (United Kingdom)

A project of the British Geological Survey (BGS).

It offers access to a million records: digital maps, scanned drilling logs, photographs, and archival publications. The materials are published under open licenses and are available for download, viewing in web maps, and integration via API.

Geoportal GEOLOGIA (Poland)

The portal of the Central Geological Database of Poland (CBDG).

It provides thematic geological data, interactive maps, and spatial search tools. Data can be exported and used in analytical tasks.

Geological Data Challenges

Despite the abundance of available sources, challenges remain that affect the quality and usability of data:

Lack of coverage: Global portals may provide uneven data representation across different regions, especially in developing countries.
Different formats and standards: The lack of a unified standard requires GIS skills and data conversion.
Updateability: Not all databases are updated regularly, which may impact the timeliness of the information.

Comparison table of digital sources of geological data

FAQ

Which digital sources are suitable for preliminary assessment of the geological conditions of an area?
State digital geological maps and archives of interpreted data, such as NGMDB and national geological portals, are optimal for this task.

Are state geological databases free?
Many state geological surveys provide free access to some of their digital geological data.

What is the difference between geological maps and spatial geological data?
Geological maps contain interpreted survey results, while geospatial data is intended for analytical processing in a GIS.

Key Takeaways

State geological surveys remain the most reliable providers of digital geological data thanks to their unified methodologies and official verification.

International and national digital portals vary in scale and detail, which determines their areas of practical application.

Combining data from multiple official digital sources improves the reliability and completeness of geological analysis.