Earthquakes

See also 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 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.