134. Earthquakes

See also 179. GEOLOGY .

bathyseism

an earthquake occurring at very deep levels of the earth.

bradyseism

the slow upward and downward motion of the earth’s crust. — bradyseismic , adj .

cataclysm

any major disaster, as an earthquake, flood, etc. See also 414. WATER . — cataclysmal , adj .

coseism

a line drawn about an epicenter through all points affected by the same seismic shock. — coseismic , adj .

epicenter

a point on the earth’s surface directly above the true center of the seismic disturbance from which the shock waves of an earthquake seem to radiate.

macroseism

a major earthquake. — macroseismic , adj .

megaseism

a violent earthquake. — megaseismic , adj .

microseism

an almost imperceptible earth tremor caused by a violent sea storm or an earthquake and detected only by a microseismometer. — microseismic , adj .

seismicity

the intensity, frequency, and distribution of earthquakes in a specific area.

seismism, seism

an earthquake. — seismic , adj .

seismogram

the record of an earthquake’s vibrations and intensity made by a seismograph.

seismograph

any of various devices for measuring and recording the vibrations and intensities of earthquakes. — seismographer , n . — seismographic, seismographical , adj .

seismography

1 . the scientific measuring and recording of the shock and vibrations of earthquakes.

2 . seismology.

seismology

the branch of geology that studies earthquakes and their effects. Also seismography . — seismologist , n . — seismologic, seismological , adj .

seismometer

a special seismograph equipped to measure the actual movement of the ground. — seismometry , n . — seismometric , adj .

teleseism

an earthquake that occurs in a part of the world far away from a recording station. — teleseismic , adj .

tromometer

an instrument for detecting or measuring very slight earth tremors.