This model buries a sand layer to a chosen depth and temperature, then applies a Kozeny-Carman-style porosity-depth relation (φ = φ₀ − k·depth) alongside Arrhenius-controlled cementation (exp(−Ea/RT)) to turn loose sand into rock. Adjusting burial depth, temperature, initial porosity and grain size shows how each diagenetic pathway changes porosity, permeability and petroleum reservoir quality.
A cross-section of sand grains being compacted and cemented over geological time, with live-updated porosity, permeability, cement fraction and petroleum potential statistics.
Drag the Burial depth, Temperature, Initial porosity φ₀ and Grain size sliders, then press ↺ Redraw to recompute the rock texture and stat readouts.
Cementation follows an Arrhenius relationship, meaning small temperature increases can dramatically accelerate mineral cement growth — a sandstone buried at 150°C can cement up in a fraction of the time it takes at 60°C.
The model applies φ = φ₀ − k·depth, so deeper burial means more overlying rock weight compacting the grains together, squeezing out pore space mechanically before any cementation even happens.
Cementation is modelled with an Arrhenius rate law, exp(−Ea/RT), so raising the Temperature slider sharply increases the rate at which dissolved minerals precipitate into pore spaces, growing the Cement fraction stat faster.
The simulation links them with k_perm = k₀·(φ/φ₀)³ — permeability scales with the cube of the porosity ratio, so even a modest porosity loss produces a much larger permeability drop, which is why oil and gas reservoirs are so sensitive to burial history.
It's the pore space fraction of the freshly deposited, uncompacted sand — typically 0.35–0.45 for well-sorted sand — before any burial, compaction or cementation has occurred.
Coarser grains pack with larger, better-connected pore throats, generally preserving more permeability at a given porosity, while finer grains compact and cement more readily, which is why the Grain size slider shifts both porosity loss rate and the Petroleum potential score.