Module 2 Flashcards
memorize (27 cards)
is the shaking caused by the rupture
(breaking) and subsequent displacement of rocks (one body of rock moving with
respect to another) beneath
Earth’s surface.
earthquake
defines an earthquake as the perceptible shaking of the surface of the Earth,
resulting from sudden release
of energy in the earth’s crust
that creates seismic waves.
USGS
The engineering principle of
____________________, which can
be used to understand earthquakes. The stress applied to a rock typically because of
ongoing plate movement results in strain or
deformation of the rock.
elastic deformation
The rock breaks and there is
displacement along the _____________________.
rupture
surface
The energy released by an
earthquake is measured by __________________.
Uses Hindu-Arabic numeration
Magnitude
How is magnitude measured?
Richter scale
Who developed richter scale? When was it developed?
Charles Richter in 1935.
is the strength of an
earthquake as perceived and
felt by people in a certain
locality.
It is a numerical rating
based on the relative effects
to people, objects,
environment, and structures
in the surrounding.
Uses Roman numeration
Intensity
3 types of faults
Normal faults
Reverse faults
Strike-slip faults
is a geological fault where the hanging wall has moved downward relative to the footwall due to extensional forces, typically associated with divergent plate boundaries.
normal fault
is a geological fault where the hanging wall has moved upward relative to the footwall due to
compressional forces, often associated with
convergent plate boundaries.
reverse/thrust fault
is a geological fault where the movement of tectonic plates occurs predominantly horizontally, parallel to the fault plane, in opposite directions, typically due to horizontal shearing forces.
strike-slip fault
Some consider a 4th type of fault. It is called an
_____________. Which is a combination of any
type of fault.
oblique-slip fault
WHERE DOES AN EARTHQUAKE
ORIGINATE?
tectonic plate boundary
The _________ is point inside the
earth where the earthquake started,
sometimes called the ___________, and the
point on the surface of the earth directly
above the focus is called the ____________.
focus
hypocenter
epicenter
ARE ENERGY WAVES THATARE GENERATED BY AN EARTHQUAKE OR EXPLOSION AND PROPAGATE WITHIN THE EARTH OR ON ITS
SURFACE.
SEISMIC WAVES
2 TYPES OF SEISMIC WAVES
Body waves
Surface waves
travel through the interior of the Earth and have a frequency higher than the surface wave.
Body waves
They have a lower frequency
than body waves.
They can be easily distinguished
on a seismogram.
Surface waves
produce stronger surface waves; the
strength of the surface waves are
reduced in deeper earthquakes.
Shallow earthquakes
2 TYPES OF BODY WAVES
Primary waves
Secondary waves
It’s the fastest kind of seismic wave,
and the first to arrive at a seismic station.
Can move through solid rock
and fluids, like water or the liquid layers
of the Earth.
It squishes and stretches the rock it
moves through just like sound waves
compress and expand the air as they
move through.
Primary waves
Primary waves are also known
as ________________, because they
push and pull
compressional waves,
is about 1.7 times slower than a P wave
only move through solids, seismologists were led to conclude that the Earth’s outer core is a
liquid
move rock particles up and down, or side-to-side, and are always perpendicular to the direction that the wave is traveling in (the direction of wave propagation
Secondary waves
