Aftershock—
an
earthquake that follows a larger
earthquake, or main shock, usually originating along
the same fault as the main shock.
Amplitude—
a measurement of the energy of a wave.
Amplitude is the displacement of the medium from
zero or the height of a wave crest or trough from a
zero point.
Body waves—
waves that move through the body
(rather than the surface) of the Earth. P waves and S
waves are body waves.
Braces or Bracing
—structural elements built into a
wall to add strength. These may be made of various
materials and connected to the building and each other
in various ways. Their ability to withstand stress
depends on the characteristics of the materials and
how they are connected.
Canopy—
a covered area that extends from the wall of
a building, protecting an entrance.
Cantilever—
a beam, girder, or other structural
member which projects beyond its supporting wall or
column.
Cartographer—
a map maker.
Cladding—
an external covering or skin applied to a
structure for aesthetic or protective purposes.
Cornice
—the exterior trim of a structure at the
meeting of the roof and wall.
Compression—
squeezing, being made to occupy less
space. P waves are called
compressional waves
because they consist of alternating compressions and
dilations, or expansions.
Consolidated—
tightly
packed, composed of particles
that are not easily separated.
Continental drift—
the
theory, first advanced by
Alfred Wegener, that Earth’s continents were
originally one land mass, pieces of which split off and
gradually migrated to form the continents we know.
Diagonal braces
—structural elements that connect
diagonal joints. These braces may be made of solid
materials or flexible materials. How they function
depends on what they are made of and how they are
connected.
Duration—
the
length of time that ground motion at a
given site shows certain characteristics. Most
earthquakes have a duration of less than one minute, in
terms of human perceptions, but waves from a large
earthquake can travel around the world for hours.
Earthquake—
a sudden shaking of the ground caused
by the passage of seismic waves. These waves are
caused by the release of energy stored in the Earth’s
crust.
Earthquake hazard—
any
geological or structural
response to an earthquake that poses a threat to human
beings and their environments.
Elevation—
in architecture, a flat scale drawing of one
side of a building.
Epicenter—
the point on Earth’s surface directly
above the location (focus) of the earthquake below the
surface.
Epitaph—
an inscription on a tombstone, often
intended to sum up the achievements of a person’s life.
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