tectonic plates

The combination of a dried-up lake that it's built over and nearby clashing tectonic plates makes Mexico City especially susceptible to earthquakes.
According to geologists, earth's tectonic plates are in constant flux. The seven major plates (and many minor ones) move in relation to each other. This movement has in pre-history had a significant effect on the current arrangement of the continents.
Now scientists have detailed the remarkable transformation of our planet's surface in a new, eye-popping computer model -- which
“Understanding this boundary between the base of cold, rigid tectonic plates and the underlying hot, convecting mantle underneath
Starting roughly 4 billion years ago, cooler parts of Earth's crust were pulled downwards into the warmer upper mantle, damaging