Geologists study ancient sedimentary rocks to
determine what sedimentary environment they formed in.
Determining ancient environments is very important to understand the
history of the Earth. It helps geologists understand how the Earth’s
surface has changed over time. Since most ancient organisms live around
environments where sedimentary rocks are formed, paleontologists need to
know the ancient environments.
One way to study environments is to compare the
sedimentary structures in ancient rocks with sedimentary structures
forming at present in modern sedimentary environments. From looking at
today’s environments, geologists can learn how sedimentary
structures form. If the rock shows the same sedimentary structure as
the modern sediment, then the rock probably formed in the same way. This
is an important way of understanding what happened in the past, even if
the deposition occurred millions of years ago.
Sand ripples along beach in South Carolina
Ripples preserved in sandstone