At BRGM (the French Geological Survey), transitioning from field observations to high-quality published maps requires a seamless digital workflow. This presentation explores how we leverage the synergy between QField and QGIS to build an integrated, industrial-scale production line for geological data.

We will break down our specialized workflow into three strategic phases:

• 1. Upstream Preparation (QGIS to QField): How we prepare complex field projects by integrating multi-source data (satellite imagery, geophysics, legacy vectors) and configuring advanced QField forms (drag-and-drop layouts, 1-N relations, and lookup registers) to ensure structured data entry.
• 2. Field Acquisition (QField): Utilizing rugged tablets to capture geological features in situ, ensuring data consistency and topological integrity right at the outcrop.
• 3. Downstream Production (QGIS & Custom Plugins): Beyond standard GIS tasks, we will showcase our internal suite of Python plugins. These tools automate post-processing and final cartographic rendering according to BRGM’s rigorous scientific standards, transforming raw SIG layers into professional map products.

By sharing our experience, we aim to demonstrate how this 100% Open Source ecosystem—enhanced by bespoke development—not only reduces data entry errors but also significantly accelerates the timeline from "rock to map."