A Practical Look at the First Week

The first week of fieldwork on the northern slopes of the Seine basin forced a series of small, concrete decisions that shaped the rest of the survey. We had planned to cover four transects across the gypsum hills, but the ground conditions after the autumn rains changed the schedule before lunch on day one.

The main constraint was access. The lower terraces, where the old limestone quarries collapse into dense scrub, required a different approach than the open crests. We switched to a staggered line of sight, using the existing paths cut by wild boar rather than clearing new ones. That choice saved time but limited the resolution of the elevation data on the first two profiles.

By day three, we had enough readings to see a pattern: the erosion rills on the south‑facing slopes were deeper than expected, and the vegetation cover—mostly boxwood and hawthorn—was holding the soil better on the steeper sections. We adjusted the sampling points to focus on the transition zones between bare gypsum and shrub cover.

The tradeoff was clear: we sacrificed a full kilometer of the planned transect to get denser readings on the critical 15‑degree slope. That decision came from a quick calculation of water runoff volume versus root depth data from the first two days. It was not elegant, but it gave us a usable dataset for the contour map.

By the end of the week, we had three complete profiles and a partial fourth. The missing section will be covered in the next visit, but the practical constraints of the first week—wet ground, limited daylight, and the real behavior of the terrain—made the final plan more honest than the original one.