Seismic trace
Encyclopedia
In seismology
, a seismic trace refers to the recorded curve from a single seismograph
when measuring ground movement. The name comes from the curve plotted by a seismograph as the paper roll rotated and the needle left a trace from which information about the subsurface could be extracted. Today's instruments record the data digitally and the word trace has come to mean the digital curve.
part of the complex
trace. By phase shifting the recorded trace by 90 degrees, we can obtain the imaginary
part of the complex trace. The complex seismic trace is a complex function whose real and imaginary part are the previously mentioned. From the complex trace, one can now define seismic attribute
s such as the complex amplitude, phase, instantaneous phase and instantaneous frequency.
Seismology
Seismology is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. The field also includes studies of earthquake effects, such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, oceanic,...
, a seismic trace refers to the recorded curve from a single seismograph
Seismometer
Seismometers are instruments that measure motions of the ground, including those of seismic waves generated by earthquakes, volcanic eruptions, and other seismic sources...
when measuring ground movement. The name comes from the curve plotted by a seismograph as the paper roll rotated and the needle left a trace from which information about the subsurface could be extracted. Today's instruments record the data digitally and the word trace has come to mean the digital curve.
Complex seismic trace
The recorded seismic trace is considered the realReal number
In mathematics, a real number is a value that represents a quantity along a continuum, such as -5 , 4/3 , 8.6 , √2 and π...
part of the complex
Complex number
A complex number is a number consisting of a real part and an imaginary part. Complex numbers extend the idea of the one-dimensional number line to the two-dimensional complex plane by using the number line for the real part and adding a vertical axis to plot the imaginary part...
trace. By phase shifting the recorded trace by 90 degrees, we can obtain the imaginary
Imaginary number
An imaginary number is any number whose square is a real number less than zero. When any real number is squared, the result is never negative, but the square of an imaginary number is always negative...
part of the complex trace. The complex seismic trace is a complex function whose real and imaginary part are the previously mentioned. From the complex trace, one can now define seismic attribute
Seismic attribute
In reflection seismology, a seismic attribute is any quantity derived from seismic data using measured time, amplitude, frequency, attenuation or any combination of these. It intends to output a subset of the data that quantifies rock and fluid properties and/or allows the recognition of geological...
s such as the complex amplitude, phase, instantaneous phase and instantaneous frequency.