Triassic Water

What did Earth look like 200 million years ago?

Almost all the land was joined together in one enormous mass, with a single ocean wrapped around it. Of the seven maps on this site, this is the one with the least water: 61.4% of the surface below sea level, against 68.6% fifty million years earlier.

The world about 200 million years ago — Late Triassic

The world about 200 million years ago. The source calls this map the Late Triassic.

Yellow is land, mid-blue is shallow sea, dark blue is deep ocean. The map is drawn flat, so places near the poles look wider than they really are.

This is one model’s answer, not a photograph. It shows the world about 200 million years ago — the age of the map itself, which is the closest the source gets to the ages on this site.

Map data: Scotese, C. R., & Wright, N. M. (2018). PALEOMAP Paleodigital Elevation Models (PaleoDEMS) for the Phanerozoic (Version 2) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.5460860 Licensed CC BY 4.0. Grid 360×180 at 1° — about 111 km per cell at the equator, so nothing the size of a town can be read from it.

One piece of land, one ocean

The first thing to notice is that you cannot pick out the continents. There is one enormous body of land with a great bite taken out of its eastern side, and everything else is water. If you looked at the far side of this world you would see ocean and almost nothing else.

That shape is why this map has the least sea of any on this site. When the land is gathered into one block rather than spread out in pieces, less of it sits low enough to flood. The share below sea level went from 68.6% at 250 million years ago to 61.4% here.

Why it changed is a bigger question than this map can answer, and this page will not guess at it. What the map gives you is the before and the after.

What was alive then

The first dinosaurs had already appeared, and the first mammals were about to. Near Swansea the rocks of this age hold both — reptile bones washed into cracks in older limestone, and shells from a shallow sea a few tens of kilometres away.

This map cannot tell you that. It has no fossils in it at all. It is a picture of where the land and water were, drawn from one reconstruction, and everything about what lived there comes from digging. Bath has the largest fossil record on this site and its rock is from close to this age.

Where this comes from

The maps
PALEOMAP Paleodigital Elevation Models (PaleoDEMS) for the Phanerozoic, version 2. Scotese, C. R., & Wright, N. M. (2018). PALEOMAP Paleodigital Elevation Models (PaleoDEMS) for the Phanerozoic (Version 2) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.5460860 Licensed CC BY 4.0. Read from a copy whose checksum is recorded in this repository, so the numbers on this page can be checked against the exact file they came from.
How sure is this?
Every map here is a reconstruction — an estimate built from evidence, not a photograph. Its authors call each one the “best guess” or average geography for the time it represents, which is a fair description and worth repeating. 1° cells — roughly 111 km at the equator. Nothing at the scale of a town can be read from this grid. The source grid is 5 million years. An age between two maps is NOT interpolated: the nearest map is used and its own age is what gets published.

One reconstruction among several. PALEOMAP draws the world here; MULLER2019 places individual points elsewhere on this site. They are different models and are never composited or averaged.

Read from the source archive on .