This simulator shows a cutaway volcanic cone with a magma reservoir below and a conduit to the vent. Adjust the magma recharge rate, the conduit conductance and the vent-opening threshold, or seal the vent, and watch reservoir overpressure, eruption outflow and stored and erupted volumes respond.
• A real-time 3D scene with 4 inspectable parts (Layered volcanic cone, Magma reservoir, Conduit and vent and Eruption plume and lava markers), with home view, focus-selected-part, auto-rotate, expand, instrument-cover and hide-labels scene tools, plus a model response curve beneath the scene. • Experiment controls: Magma recharge (0.1-2 model volume/s); Conduit conductance (0.1-1 model volume/(s·MPa)); Vent-opening threshold (2-10 MPa); seal the vent; show explanatory motion markers; pause/resume, 0.1 s and 1 s single-step buttons, four playback speeds and a restart button. • A Curves & measurements tab with a parameter-comparison chart, a live-measurements chart, the model equations and snapshot readouts (Reservoir overpressure; Modeled eruption outflow; Stored excess volume; Cumulative erupted volume). • An Experiments tab with 2 guided presets (blocked vent and low threshold) and a Model verification bench that runs independent fresh models, plus a timestamped event log and a copyable trial report. • A Learn & assess tab with guided lessons, a knowledge-check quiz with reset and a written model-scope statement linking to a technical reference.
The reservoir stores excess volume with a compliance of 2 model volume per MPa, so C dP/dt = Qin - Qout. Outflow is zero until overpressure exceeds the opening threshold, after which Qout equals the conductance times the excess pressure; sealing the vent sets outflow to zero.
The lab reports reservoir overpressure, modeled eruption outflow, stored excess volume and cumulative erupted volume, and stored plus erupted volume equals the integrated recharge.
At steady pressure recharge and outflow must balance, because storage stops changing only when inflow equals outflow. A blocked vent stores everything as rising pressure, while a low threshold lets the vent open early.
Visible glow does not imply the whole mantle is molten; magma occupies localized regions. The model uses arbitrary volume units and omits gas exsolution, fragmentation, buoyancy, viscosity changes and country-rock fracture. It is not a hazard model, and sealing does not include real failure of a plug.
Recharge and outflow. Stored volume stops changing only when magma enters the reservoir at the same rate it leaves through the vent.
Modeled outflow drops to zero, so all recharge is stored and overpressure climbs. The model does not include real failure of a plug, so it will not simulate an explosive release.
No. Magma occupies localized regions such as reservoirs and conduits, while most of the mantle is solid rock.
No. It is a lumped pressure and compliance analogy in arbitrary units that omits volatile exsolution, fragmentation, viscosity evolution and rock fracture, and is not a hazard model.