Sharp edges in a function are created by this part of the amplitude spectrum
What are the high frequencies?
100
This is the data that is used to model the subsurface in a refraction seismic survey
What are the travel times of the first arrivals?
100
Shot gathers are resorted into these for NMO and stacking.
What are CMP gathers?
100
Surface wave methods use the energy in these waves to determine the subsurface velocity structure.
What are Rayleigh waves?
100
This is the fundamental unit of g in geophysical studies, equal to 0.001 cm/s2.
What is a milliGal?
200
This type of function has a narrower amplitude spectrum.
What is a wider function?
200
This is the minimum length of the geophone spread needed in a refraction survey in terms of the maximum depth of interest.
What is 3?
200
Static corrections are critical because of this property of the weathered layer.
What is low velocity or slowness?
200
This information is the goal of surface wave inversions.
What is shear wave velocity profiles or structure?
200
Gravity varies by about this percentage from the pole to the equator of the Earth.
What is 0.5%?
300
This operation combines an input function and an impulse response function to yield an output function.
What is convolution?
300
These types of layers cannot be found using refraction seismic methods.
What are low velocity layers?
300
Velocity analysis is most commonly performed on this type of plot.
What is a semblance plot?
300
This is the data curve extracted from from a multichannel suface wave survey.
What is the fundamental mode dispersion curve?
300
This correction assumes that elevation is gained by ascending infinite slabs of material.
What is the simple Bouguer correction?
400
Time is transformed into frequency while distance or offset are transformed into this.
What is wavenumber or spatial frequency?
400
This type of processing would be ideal for a gently undulating bedrock surface beneath unconsolidated alluvium.
What is delay-time or plus-minus method.
400
This is the best way to remove ground roll without destroying underlying reflections
What is FK filtering?
400
This method is actually a form of passive source MASW performed with a linear array of geophones.
What is ReMi?
400
This type of anomaly can confirm or reject isostatic compensation of topography.
What is the free-air anomaly?
500
Convolution in the time domain is equivalent to this operation on the spectra.
What is multiplication?
500
This method can handle more irregular surfaces than the plus-minus method as well as laterally varying velocity, but it takes more data and more computational effort.
What is the Generalized Reciprocal Method (GRM)?
500
This is the best, but most expensive form of seismic migration.
What is pre-stack depth migration (PSDM)?
500
These are two reasons that engineering firms love a surface wave survey.
What are 1) it's easy 2) it's most immune to ambient noise and/or 3) it produces shear wave data?
500
This is the depth of a sphere of anomalous mass.
What is 1.3 times the half-max half-width of the anomaly?