Marine High–Resolution Seismic Data Processing
Advanced denoising, high–resolution offshore statics, designature (automatic wavelet estimation, deghosting, debubbling, deconvolutions), efficient demultiple algorythms for multi–channel (SRME) and even single–channel data (Zero–Offset Demultiple), 3D regularization, pre–stack and post–stack migrations—all these algorithms are available in RadExPro and are capable of improving the quality of the processing result significantly.
An experienced processor would particularly enjoy the outstanding flexibility of the software allowing even the most sophisticated processing scenarios to be easily implemented in the modern user–friendly interface—for only a fraction of the price of any big seismic processing system on the market.
Outstanding Results of Marine High–Resolution Seismic Data Processing in RadExPro
Ultra–high resolution (up to 3000 Hz) data, acquired with a sparker source, water depth 2–5 meters.
CDP interval is 1 m.
Processing was carried in RadExPro seismic software by GeoSurveys.
Processing of small volume (40 in3) airgun seismic data, acquired in the Barent Sea.
Data courtesy of Tromsø University.
3D regularization is dedicated for interpolating 3D seismic data by common offsets on the regular grid. Algorithm is based on wavefield reconstruction in F–Kx–Ky domain.
Inline before and after regularization
Time slice before and after regularization
Data courtesy of DONG Energy, prestack processing in RadExPro by GeoSurveys
Real–Time Marine Seismic Acquisition QC
Some examples of QC products are below:
Shot gather display
Standard fully customizable shot gather display.
A user–defined number of shots can be stored in memory and reviewed during acquisition.
Spectrum comparison for a number of shots
Several noisy shots can be seen at the start of the profile.
Near–trace gather display
NFH signature display
Near–field hydrophone and its bubble time period graph are displayed.
RMS amplitude map
Horizontal scale is shot number, vertical—channel number. Notice purple stripes on the image. The horizontal one indicates that channel 55 is dead, the vertical one—that shot number 1360 was bad. Purple areas around channels 200–240 indicate week channels due to weather conditions. Just one amplitude map can tell us a lot about what is happening onboard!
All QC images are saved to pre–defined folders automatically after each line and stored in structured order, from where can be easily imported to an EOL report.
Furthermore, all QC results can be saved into a database, to be later played back or exported into SEG–Y files.
SharpSeis Deghosting/Broadband Processing
RadExPro is perfectly capable for in–depth processing of on–land near–surface reflection data.
- Intuitive geometry assignment tool for most standard linear 2D acquisition scenarios
- Loading geometry from ASCII tables and SPS–files for more complicated cases
- Crooked–line 2D CMP binning
- Both impulsive and vibroseis data processing
- Near–surface 3D seismic data processing
- Multicomponent data processing
- Exhaustive set of signal processing algorithms and 2D filters
- Interactive velocity analysis
- Pre–stack and post–stack Kirchhoff migration
RadExPro includes Plus–Minus and GRM methods for seismic refraction.
First–break picking is made semi–automatically for all shot points at once, in one window.
In the automatic mode of Plus–Minus method, refracting boundaries are built in one click—the only thing required is prior assignment of time–curve segments to layers. In the manual mode, an experienced geophysicist can control the whole process and make some fine–tuning at any stage: building composite travel time curves, leveling of reciprocal times, computing velocity analysis and time–depth functions, and, finally, building the refraction boundaries.
In cases that are more complicated, use of GRM instead of Plus–Minus allows simultaneous reconstruction of both geometry of refracting boundaries and lateral changes of velocities along them more accurately.
A dedicated module for Multichannel Analysis of Surface Wave (MASW) available in the RadExPro for easy and competent evaluation of S–wave velocities of the subsurface.
- Input from SEG–2, SEG–D, SEG–Y…
- Intuitive geometry assignment
- FV and FK dispersion images calculated independently—you get the best of both
- 2–3 clicks to extract a dispersion curve accurately—with semi–automatic smart picking algorithm
- 1 click to save all dispersion curves at once and send them to inversion
- Joint inversion of fundamental and higher modes, unlimited number of modes allowed
- Exceptionally user–friendly design—you will enjoy it!
FV and FK dispersion images with dispersion curves picked: accurate, easy and very fast!
You can invert all extracted modes jointly or indicate a particular combination of modes for the inversion. For instance, you can, first, invert the fundamental mode only (which is more stable) and then use the result as the initial model for joint inversion with the higher modes.
You can invert all dispersion curves from all receiver mid–stations in one click, or thoroughly control inversion process at each location. You can also make a thoroughly controlled inversion at one location and then use the result as an initial model for automatic inversion at all other locations along the line.
Resulting Vs section can be printed or exported to ASCII (together with Vs30) or GRD files.
Travel–Time Tomography module in RadExPro provides an intuitive interactive tool for recovering of 2D velocity model from the first–arrival travel–time curves.
You can use Herglotz–Wiechert inversion for automatic generation of the initial model or define it using interactive layers and boreholes. Of course, you can also edit the model grid manually.
The tomography algorithm used is based on the known Occam inversion, however with some important modification. Beside velocity, each cell of the grid has confidence parameter that takes values from 0 to 1. Use this parameter to specify how confident you are in any particular part of the initial model. For instance, near the borehole you are pretty sure about velocities—why not to tell the software explicitly that you don’t want the algorithm to change them too much?
Something went wrong while tomography is calculated and you are unhappy with the ongoing values? You can pause the calculation at any iteration, change any parameters (and even the current model!) and continue. You can also scroll back through the iterations, use the result of any of them as a new initial model and start the whole process again with modified parameters.