the.com/geological time
the clock where 'recently' means the last ice age and 'soon' means never in your lifetime.
means a timescale for measuring earth's history in millions and billions of years, using rock layers and fossils instead of clocks and calendars.
from formalized in the 1800s when geologists like William Smith realized rock strata stack in predictable order, letting them read the planet's age from its layers like a very slow book.
deep time coinedjohn mcphee popularized the term in 1981
human history's shareabout 0.0002 percent of earth's total age
eon lengththe current eon alone spans 4 billion years