An animated 3D Earth sphere with moving tectonic plates. Mountains rise where plates collide (convergent boundaries), rifts open where they pull apart (divergent), and earthquakes mark transform boundaries.
Plate boundaries are classified as convergent, divergent and transform. Collision speed and angle determine whether mountains, trenches or volcanic arcs form.
Rotate the globe to see all major plates. Watch mountains build at convergent boundaries. Speed up time to see plate motion.
Tectonic plates move about 2-15 cm per year — roughly the speed your fingernails grow. In 250 million years, all continents will merge again into a supercontinent called "Pangaea Proxima".
This simulation renders a 3D Earth using Three.js and WebGL, with seven major lithospheric plates drawn as coloured point clouds and boundary rings projected onto the globe. Each plate is defined as a spherical cap by a centre direction and angular radius, and is given a small drift velocity. Where two plate caps approach within their combined angular distance, a white mountain ridge is generated to represent uplift at a convergent boundary.
Drag to rotate the globe with OrbitControls and scroll to zoom. The Speed slider scales how fast geological time advances (the clock counts down from 250 million years ago through the Paleozoic, Mesozoic and Cenozoic eras), and the Mountain height slider exaggerates the vertical scale of collision ridges. Plate tectonics is the unifying theory of geology, explaining earthquakes, mountain belts, ocean trenches and the slow reshaping of continents over deep time.
What does this simulation actually show?
It shows a stylised 3D Earth with seven major tectonic plates drifting across the surface. As plate boundaries drift close together, white ridges appear to mark where collision and uplift would occur. A geological clock counts down from 250 million years ago to the present, illustrating that plate motion plays out over enormous spans of time.
How are the plates represented mathematically?
Each plate is defined as a spherical cap: a centre direction given by spherical coordinates (theta, phi) plus an angular radius in radians. Points sampled on the unit sphere that lie within that angular distance of the centre belong to the plate. The boundary is drawn as a circle of constant angular radius around the centre, and each plate is nudged by a small drift velocity every frame.
What do the two sliders do?
The Speed slider (0 to 3) scales how quickly time advances; at speed 1 roughly one real second equals five million years of geological time. The Mountain height slider (0 to 3) multiplies the vertical exaggeration and opacity of the collision ridges, so you can make the mountain belts more or less prominent without changing the plate motion itself.
The legend lists Pacific (red), Eurasian (orange), North American (teal), African (yellow), Antarctic (blue), Indo-Australian (light blue) and South American (dark red). Each plate's points, boundary ring and the matching colour swatch in the legend share the same hue, so you can track an individual plate as it drifts around the globe.
For every pair of plates the code measures the angular distance between their centres. If that distance is less than ninety-five per cent of their combined radii, the plates are treated as colliding and a ridge is drawn at the midpoint direction. Ridge height follows a Gaussian-like profile, exp(-t squared times 8), scaled by the Mountain height slider and a touch of randomness for a natural look.
No. It is an educational visualisation, not a geophysical simulation. Real plates move at a few centimetres per year driven by mantle convection, ridge push and slab pull, and their shapes are irregular. Here the plates are idealised circular caps with fixed arbitrary drift velocities, so the goal is to convey the concepts of drift, boundaries and collision rather than to reproduce real Earth dynamics.
At convergent boundaries plates move towards each other, building mountains, ocean trenches or volcanic arcs. At divergent boundaries they pull apart, creating rifts and new crust. At transform boundaries they slide past one another, producing earthquakes such as those along the San Andreas Fault. This simulation focuses chiefly on the mountain-building convergent case.
Around 250 million years ago, near the Permian-Triassic boundary, Earth's landmasses were assembled into the supercontinent Pangaea before rifting apart into today's continents. Starting the clock there lets the simulation symbolically sweep through the Mesozoic age of dinosaurs and the Cenozoic age of mammals down to the present day, shown by the coloured era bar.
Real plates creep along at roughly 2 to 15 centimetres per year, comparable to the rate at which your fingernails grow. Over millions of years these tiny movements add up to thousands of kilometres, opening oceans and raising mountain ranges such as the Himalayas, which are still rising as the Indian plate pushes into Eurasia.
Real tectonic plate outlines are complex polygons that would require detailed map data to render. Modelling each plate as a circular spherical cap keeps the geometry simple and fast: a single centre direction and radius fully define the shape, the boundary ring is easy to compute, and collisions reduce to comparing angular distances. The trade-off is geographic accuracy in exchange for clarity and smooth real-time animation.