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• Interval transit time
  This is the inverse of velocity and is what is displayed on a sonic log, usually in units of μs/ft or μs
  205 bytes (40 words) - 20:03, 14 April 2014
• Seismic data: building a stratigraphic model
  ...generated where there is a contrast in impedance (which is the product of velocity and density). ==Velocity data sources==
  5 KB (805 words) - 19:06, 27 January 2022
• Seismic data - creating an integrated structure map
  ...er such as glacial till). It also fails when there are extreme [[lateral]] velocity variations in the subsurface (subsalt, subthrust, etc.). When it works, thi # Calculate depth conversion velocity at locations where both well and seismic time picks exist.
  7 KB (1,117 words) - 17:51, 25 January 2022
• Synthetic seismograms: correlation to other data
  ...away from the vertical. If anisotropy is present (and it usually is), then velocity depends on the direction the wave is traveling. It is not uncommon to see a
  3 KB (486 words) - 19:10, 27 January 2022
• Pressure prediction: analysis of well-log and seismic data
  ==Seismic velocity== ...dicate an undercompacted (overpressured) interval. Unusually fast interval velocity, conversely, may indicate overcompaction (underpressure).
  5 KB (733 words) - 17:57, 17 February 2022
• Seismic data and mapping structure
  | Classic || Mapping a surface of interest (from data) using [[Average velocity|average velocities]] ...a (with time axis) converted to a depth cube using a ''V'' ( ''X, Y, Z'' ) velocity model
  2 KB (320 words) - 19:10, 27 January 2022
• Seismic data: identifying reflectors
  ...fig12-8.png|300px|thumb|{{figure number|1}}Sonic log converted to time and velocity. From Liner;<ref name=Liner1999>Liner, C., 1999, Elements of 3-D Seismology ...a [[Basic open hole tools#Sonic|sonic]] log has been converted to time and velocity. Note that the time axis on the seismic section and the converted sonic log
  2 KB (348 words) - 19:10, 27 January 2022
• Seismic data preparation for mapping
  # Identify online wells with velocity control. ...oints. Whatever the method, it should also be used in the depth conversion velocity map (next section). The wells-only depth structure map is a useful baseline
  7 KB (1,064 words) - 19:11, 27 January 2022
• Full waveform acoustic logging
  ...about the lithology and the fluid content of the formation. Stoneley wave velocity and amplitude have been shown to be useful in the detection of fractures an ...hat is slower than both the formation shear wave velocity and the acoustic velocity of the borehole fluid.
  10 KB (1,530 words) - 20:47, 19 January 2022
• Seismic facies analysis
  * [http://wiki.seg.org/wiki/Dictionary:Interval_velocity Interval velocity] * Velocity and density contrasts of individual interfaces
  6 KB (809 words) - 17:46, 4 February 2022
• Seismic data - mapping with two-dimensional data
  ...teral differences in velocity on conversion of time and depth. If a single velocity function of 8300 ft/sec were used, errors of +6 ft at A and -440 ft at B wo mapping-with-two-dimensional-seismic-data_fig5.png|{{figure number|5}}Velocity map with velocities marked at grid intersections.
  13 KB (1,936 words) - 21:29, 21 January 2022
• Magnetotellurics case history: Precambrian overthrust (Northwestern Colorado)
  ...where high-velocity (high-resistivity, low-conductivity) rocks overlie low-velocity (low-resistivity, high-conductivity) sediments.
  3 KB (383 words) - 15:13, 31 January 2022
• 3-D seismic data: immersive visualization
  ==Calculating depth conversion velocity==
  4 KB (601 words) - 19:49, 27 January 2022
• Seismic inversion
  ...rth reflections as a function of time to the geologist's view of the earth velocity as a function of depth. This is not as easy as it may seem. The reason for ...ide, we introduce geological constraints taken from a sonic log or seismic velocity information and produce a forward model. We then combine the information fr
  8 KB (1,196 words) - 18:48, 21 January 2022
• Checkshots and vertical seismic profiles
  ...daries of these units need to be mapped in depth. Thus, the concept of the velocity checkshot survey has been developed to establish time-depth calibration fun ...s measured.<ref name=pt07r1>Anstey, N. A., and R. L. Geyer, 1987, Borehole velocity measurements and the synthetic seismogram: Boston, MA, IHRDC, 355 p.</ref>
  11 KB (1,599 words) - 20:48, 19 January 2022
• Seismic migration
  ...ey conducted over a subsurface medium that is homogeneous (constant P-wave velocity) with the exception of an isolated boulder at some depth. Also shown are th ...for a subsurface consisting of a single dipping reflector. For a constant-velocity subsurface, the many weak diffractions from very closely spaced points alon
  14 KB (2,045 words) - 20:21, 21 January 2022
• Vertical and lateral seismic resolution and attenuation
  ...ocity and a 15-Hz wavelet. Resolution decreases rapidly with depth because velocity increases and frequency decreases. ...contributing to limit the horizontal resolution include uncertainty in the velocity and the mathematical completeness of the migration algorithm. One of the mo
  8 KB (1,164 words) - 20:24, 21 January 2022
• Seismic data display
  ...ks were reversed (that is, travel is from a high velocity rock to a slower velocity rock), the coefficient of reflection is said to be ''negative'' and is disp ...raphic sequences. A display of a variation in amplitude, phase, frequency, velocity, or any other trace-related attribute can be represented by different color
  9 KB (1,404 words) - 21:17, 19 January 2022
• Cross-borehole tomography
  ...presented by a color-coded map in which a color is assigned to the seismic velocity at each point. This map, or plot, is referred to as a ''tomogram''. Other d ...2.png|Figure 2]]. These traveltime data are then used to infer the seismic velocity field between the wellbores. If attenuation measurements can be made on the
  14 KB (2,060 words) - 20:51, 19 January 2022
• Amplitude (seismic)
  : <math>\text{IA} = \text{Density} \times \text{Velocity}</math> ...sure and pore pressure. The relationship between gas saturation and P wave velocity drops drastically resulting in the formation of anomalies such as DHI, AVO,
  8 KB (1,291 words) - 15:49, 18 January 2017

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