Overview
- Researchers report that the Damköhler number governs whether stalagmites grow conical, columnar, or flat-topped.
- The parameter combines calcite precipitation rate, water flow rate, and the base area of the formation.
- Model regimes map to forms: values below one yield sharp cones, around one produce rounded columns, and above one generate flat tops.
- Flat-topped growth commonly occurs under slow dripping with long ceiling-to-tip distances, often on the order of ten meters or more.
- X-ray tomography and 3D scans of Postojna Cave specimens matched the analytical predictions, and the team found shape-dependent carbon isotope patterns that affect paleoclimate interpretation.