This printable crossword puzzle on the topic of Rocks & Minerals has 20 clues. Answers range from 3 to 19 letters long. This crossword is also available to download as a Microsoft Word document or a PDF.
explosion of life to present
eon before Phanerozoic eon
the era we are in now
dinosaur era
explosion of life
first period of Paleozoic Era and animals started appearing in the ocean
first land plants started appearing
animals like spiders started to move onto land
the age of the fishes
plant and animals on land were at huge sizes not seen today
last period of the Paleozoic Era
first period of the Mesozoic Era and dinosaurs were now around
Pangea was starting to break apart
last period of the Mesozoic Era and dinosaurs became extinct at the end of this period
it is the first period of the Cenozoic Era and mammals are starting to be in control
the Megalodon shark came around and later died during this period
it is the last period of the Cenozoic Era and it is the period we are currently in
the largest division of geologic time, comprising two or more eras
a system of chronologic notation reckoned from a given date and it is smaller than an eon
a space of time between two events or a portion of time and it is smaller than an Era