Seismic moment seismic moment tensor formula_8 (a symmetric tensor, but not necessarily a double couple tensor), the seismic moment is Seismic moment Seismic moment is a quantity used by seismologists to measure the size of an earthquake. The scalar seismic moment formula_1 is defined by the equation formula_2, where formula_1 thus has dimensions of torque, measured in newton meters. The connection between seismic moment and a torque is natural in the representation of seismic sources as a pair of force couples. Seismic moment is not a measure of energy. The relations between seismic moment, potential energy drop and radiated energy are indirect
Seismic trace 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 attributes such as the complex amplitude, phase, instantaneous phase and instantaneous frequency. Seismic trace 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