Results tagged “Geology”

A day is the time for Earth to make one complete rotation on its axis, a year is the time for Earth to make one revolution around the Sun -- reminders that basic units of time and periods on Earth are intimately linked to our planet's motion in space relative to the Sun. In fact, we mostly live our lives to the rhythm of these astronomical cycles.

The timeline of the Earth's history reveals quasi-periodicity of the geological record over the last 542 Myr, on timescales close, in the order of magnitude, to 1 Myr. What is the origin of this quasi-periodicity? What is the nature of the global events that define the boundaries of the geological time scale?

A spark from a lightning bolt, interstellar dust, or a subsea volcano could have triggered the very first life on Earth. But what happened next?

« Previous  1  Next »