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🪨 Columnar Basalt Jointing Lab

Explore how slow, uniform cooling of thick basalt lava sheets generates tensile stress that self-organizes into the hexagonal rock columns seen at Giant's Causeway and Devils Tower.

Geology & Earth Science3DModerate60 FPS🌍 Earth

The simulator demonstrates how tensile stress builds up in a cooling, contracting sheet of rock, how that stress triggers crack nucleation once it exceeds fracture strength, and how many simultaneously growing cracks self-organize through their competing stress fields into a near-hexagonal polygon network, while also showing how the cooling-front direction sets each column's growth axis.

🔬 What It Demonstrates

🎮 How to Use

Set the cooling rate and cooling-surface uniformity, then start the simulation to watch crack-initiation points appear across the surface and grow inward. Adjust the cooling-boundary shape to see column axes curve to follow the changing heat-flow direction, and compare fast, uneven cooling runs against slow, uniform ones to see how column width, straightness, and hexagonal regularity change.

💡 Did You Know?

Did you know the individual crack-growth increments that build each column are often preserved as faint horizontal ridges on the column faces, called chisel marks, essentially a natural growth-ring record of exactly how far the crack advanced during each pause in the cooling process?

⚙ Under the hood

Explore how slow, uniform cooling of thick basalt lava sheets generates tensile stress that self-organizes into the hexagonal rock columns seen at Giant's Causeway and Devils Tower.

geologyvolcanologybasaltcolumnar jointingthermal stresscrack propagationigneous petrologyearth science

3D · Three.js / WebGL renderer · 60 FPS target · runs fully client-side, no install