By this time, the valley was in much the same geographic state as it exists in today, with one exception the presence of artesian springs that bubbled to the surface in several areas.
Artesian springs have changed over time.
mnli hypothesis: Artesian springs have changed over time. premise: By this time, the valley was in much the same geographic state as it exists in today, with one exception the presence of artesian springs that bubbled to the surface in several areas.