A stratigraphy game · 4.6 billion years
Read the rock record — stack the ages, drill the core.
Four games and a reference chart, all keyed to the real geologic time scale: sequence the ages oldest-to-youngest, drill a core down through deep time, match minerals and dig-site finds, or survive the Hadean magma ocean. Pick a tab below — your progress saves on this device.
You're handed a jumble of cards from Earth's history — periods, extinctions, ancestors, mountains, eruptions. Click them from oldest to youngest and watch them settle into the core, oldest at the base. Pick a deck to study one theme, or take the whole record mixed.
Which is oldest? Click it first.
Sink a borehole through deep time. Every strike drills you further into the past — cross a boundary and the core yields a discovery. Bank research points, upgrade the rig, and reach the Hadean crust at 4,600 Ma.
Spend research points on a sharper bit or steadier automation.
What the borehole has passed through, most recent first.
Swap two neighbours to line up three or more of a kind and clear them. Match four and you forge a tool — the archaeologist's trowel or the geologist's rock hammer, which clears a whole row or column. Five makes a bigger charge. Same board, two skins — flip between the geology and anthropology themes any time.
In a smelter, the slag floats on the molten iron. The newborn Earth ran the same separation at planetary scale — iron sank to forge the core, and the light silicate slag rose, chilled, and stiffened into the first crust. You live on that slag. Hop raft to raft across the Hadean magma ocean, pocket zircons, dodge the bombardment, and hold on from 4,500 Ma to the dawn of the Archean.
Click or tap a raft inside the dashed ring to hop to it — arrow keys and WASD work too. New slag freezes at the glowing ridge on the left; the trench on the right eats everything that drifts into it. Don't ride your raft all the way down.
The whole record at a glance — the International Chronostratigraphic Chart, read the way strata stack: youngest at the top, the Hadean crust at the bottom. The colours are the chart's own; every card in both games is keyed to them.
Ages in millions of years before present (Ma), after the ICS 2023 time scale. Boundary dates are rounded; several carry real uncertainty of a million years or more.