Earth
94 million years ago

What's going on here?

• Pangaea continues to breakup. By the end of the Cretaceous the full length of the Atlantic Ocean has opened, but Australia and Antarctica remain joined.
  
• In the southern hemisphere, India breaks away from Africa and heads northward at a truly remarkable pace.
  
• In the USA, the western margin continues to grow as slivers of continental and oceanic crust are accreted along the active convergent boundary. The Rocky Mountains rise.
  
• Sea level was over 100 meters (300 ft.) higher than today, allowing shallow seas to invade and cover some continental interiors.

Reconstructing ancient Earth

These remarkable figures are produced by C.R. Scotese and the PALEOMAP project. Geologists call these illustrations paleogeographic reconstructions, because they illustrate the reconstructed geography of our Earth at some time in the past.

Making a paleogeographic reconstruction begins by examining several lines of evidence including: paleomagnetism, magnetic anomalies, paleobiogeography, paleoclimatology, and geologic history. By combining all available evidence, geologists are able to construct paleogeographic maps, such as these, that interpret how the geography might have appeared at a specific location and time in the past. Paleogeographic maps are continually being refined as more evidence is collected.

To find out more about how paleogeographic reconstructions are made visit the PALEOMAP project site.

• Learn more about this time period at the PALEOMAP project site.
• Learn more about geologic time.
• Learn more about plate tectonics.

Move forward or back in time.
| Today | 0.018 | 14 | 50 | 69 | 94 | 152 | 195 | 237 | 255 | 306 | 356 | 390 | 425 | 458 | 514 | 650 |
Time in millions of years. Jump back to visit any time!

Scotese, C. R., 1997. Paleogeographic Atlas, PALEOMAP Progress Report 90-0497, Department of Geology, University of Texas at Arlington, Arlington, Texas, 37 pp.

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This page was last updated on 01/13/04