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Earth Science Cheat Sheet (DRAFT) by

This is what I learned from the first semester of Earth Science

This is a draft cheat sheet. It is a work in progress and is not finished yet.

Relative Age Dating

Principle of Superp­osi­tion: comparison of dates
Principle of Lateral Continuity all rock formations thin out at the ends to have a lenticular shape

Relative Age:Un­com­for­mities

the boundary between igneou­s/m­eta­morphic and sedime­ntary
part of the formation is tilted but it is covered by a flat deposit
there is a gap in time between sedime­ntary layers
There are three types of unconf­orm­ities that you can observe in rock formations

Minerals vs Non-Mi­nerals

Is it inorganic?
inorganic: not made of living things or the remains of living things
Does it occur naturally
naturally: forms and exists in nature
Is it a Crysta­lline Solid
A crysta­lline solid is whe its atoms are arranged inan orderly way
Consistent chem. comp.
for each atom of this, there are atom of this
If yes to all 4 questions, it is a mineral. Otherwise, it is not a mineral.

Silicates and Non-Si­licates

Silicone + Oxygen + fledspar, potassium, or sodium is a silicate
Feldspar is the most common case of silicates
96% of the Earth's crust is composed of Silicates
50% of the silicates are Feldspar and quartz
non-si­licates are basically the rest of the minerals that are not silicates
They make up the rest 4% of the Earth's crust
They are split into 6 groups
CO 3
Cl or F + Na,K, or Ca
Native elements
O + anything but Si
SO 4
S + I + anything else


How earthq­uakes start:
stress builds up at fault to the point where it is locked when pressure gets too great, the rocks slip and create the earthquake
Elastic rebound
like a slinky, it deforms then settles back to its original spot
Seismic Waves
Body Wave
travels through the middle of the bodies
can go through solids, liquids, and gases and faster than S-waves
can only go through solids and slower than P-waves
Surface Wave
travels along the surface of the body
Rayleigh Waves
elliptical rolling motions
Love Waves
Shadow zones
Parts of the Earth where body waves can't reach