THE MAGNITUDE OF GEOLOGIC TIME

The concept of Geologic time is new to many nongeologists. We are accustomed to dealing with increments of time that are measured in hours, days and years. By contrast, geologists deal with vast time periods - millions or billions of years.

Geologist may characterize a geologic event that occured 100 million years ago as a "recent" event - in the context or Eartth's 4.6 billion-year history. And a rock sample dated at 10 million years may be called "young".

To understand the magnitude of geologic time, take a look at complete Geologic Time Scale (Figure 7.1).

You can find out even more at the web site of International Commission on Stratigraphy.

Slika 7.1: Geološka časovna lestvica.
/ Figure 7.1: Geologic Time Scale.

GEOLOŠKI ČAS - VELIKOSTNI RAZRED ZASE

Pojem Geloškega časa je nov za mnoge negeologe. Navajeni smo na časovne enote kot so ure, dnevi in leta. V nasprotju s tem pa lahko geolog dogodek izpred 100 milijonov let označi za "nedavno dogajanje" - ker ga primerja s 4,6 milijarde let Zemeljske zgodovine. Na ta način tudi kamnino nastalo pred 10 milijoni let označi za "mlado".

Za razumevanje velikostnega razreda geološkega časa, si oglej celotno Geološko časovno lestvico (slika 7.1).

Še več lahko najdete na spletni strani International Commission on Stratigraphy.