Author: Mike Cline, T/X Resources
It’s pretty common knowledge that sunlight is composed of many different frequencies (colors) , and we perceive the color of an object by the color(s) that is/are reflected from the object—that is, an object is red because all of the other colors are absorbed (or filtered out) by the object.
We also know that seismic data contains many different frequencies, usually within a range from about 6-120 Hz (Hertz, or cycles per second). Have you ever considered that seismic data can be similarly filtered to reveal its “colors”? I know that this is probably pretty basic stuff for most of you, but bear with me for a minute so that I can better illustrate how you can eliminate most of the seismic frequencies, to reveal hidden features. Some might call it the “poor man’s” spectral decomposition.
Author: Mike Cline, T/X Resources
Do you ever need to use your SMT fault polygons for other applications? For example, I quite often convert them to an SMT culture layer, as a fault QC (quality control) tool, or use them in Surfer, when I need extended gridding capabilities.
The benefit of having an individual horizon’s fault polygons converted to an SMT culture layer is that you can easily keep the fault strikes consistent when working on an adjacent horizon, by overposting the culture layer onto your active horizon. I normally create fault planes on all of the faults that I see on multiple lines. However, some faults don’t extend far enough to be seen on more than one line, so it’s difficult to fault plane them with the lack of control points—a common occurrence in 2D projects, with widely-spaced lines (eg. regional projects).
Golden Software’s Surfer program has a wide array of gridding, and grid-manipulation capabilities, but it only uses the proprietary “bln” file format for faults. So, you will need to convert your SMT fault polygons to this format before you can use them in Surfer.
Author: Mike Cline, T/X Resources
No, the title isn’t about those difficult teenage years, it is related to the subtle details of seismic phase determination. Sorry if you thought that I was going to solve one of life’s little mysteries. 
How many times have you correlated two different sets of intersecting seis- mic data, and had difficulty trying to decide which phase rotations produce the best character match? For example, when you were trying to tie a syn- thetic seismogram with a seismic line, or correlate two seismic lines of various vintages. I have (many times), and until I figured this out, I sometimes had nagging doubts about my selections.
Here’s how I do it now. The four columns of traces below were taken from a larger synthetic in a singe wellbore, and they represent four different phase rotations. From left-to-right: zero degrees, 90 degrees, 180 degrees, and 270 degrees. Note that the synthetic time interval that I chose for this example has no particular significance, other than it was relatively compact, and had many of the phase details that I wanted to illustrate.
See the larger Adobe Reader pdf file.
Author: Mike Cline, T/X Resources
For those who read my previous posting, “Making the Case for Synthetic Seismograms“, but didn’t currently have a program to generate your own synthetics, I thought that I would include a few links to the programs that I knew about. All of the programs listed below, except SMT’s SynPak, are stand-alone programs, or part of a group of software related to synthetics (log editing, AVO modeling, etc.)—at least that I could determine from their websites.
Please note that I have only used the first two programs in the list, and cannot recommend any of the remaining software, relative to how accurate they are, how well they perform, etc. The list is provided for your informa- tion, and convenience only.
Author: Mike Cline, T/X Resources
I was just notified that the instructions in the info page of the Culture Symbol Spreadsheet (posted on 02/08/08) were in error.
I had copied-and-pasted the intial text, for the info page, from another spreadsheet, and thought that I had made the appropriate changes. However, I may have uploaded the wrong version when I finished.
Sorry for any confusion, previously. I have corrected the version in the original posting, but here is the corrected Culture Symbol Spreadsheet, along with the ascii file that goes with it.
Copyright © T/X RESOURCES, 1995-2008. All Rights Reserved.
Author: Mike Cline, T/X Resources
Here’s the latest in the series of T/X Resources spreadsheets designed to help when you need to create symbols to import as an SMT culture layer.
In the image below, a variety of symbols have been created to highlight certain wellbore attributes. For example, they could represent producing formations, hydrocarbon shows, well log types, or test results. You can also vary the symbol sizes, and colors, to represent a ranking order, such as production volumes, etc. It doesn’t really matter what you want to show on your map—this is an easy way to do it.
See the larger Adobe Reader pdf file.
Author: Mike Cline, T/X Resources
The following is an example of an easy method to import culture lines into an SMT project, using a spreadsheet formatted as an SMT culture line file. Note that this is also applicable for importing polygons.
Suppose you have an SMT project that includes both 2D and 3D seismic data, but you only want to show the 2D line location overlays without the 3D line overlays, to reduce map clutter. Normally, SMT’s 2d/3dPak module only has the option to have all seismic line locations turned on, or to have them all turned off.
In the examples below, the first image, annotated “WITH ALL SURVEY LINES” is how a map would look with the Display Survey Line Option selected (Surveys>Survey Annotation> Line Options>Display Survey Lines). Often, this creates a lot of map clutter (in my opinion), especially if you have many 2D lines, or they are concentrated in one area. This map clutter can distract from the structure map, or other focus of the display.
See the larger Adobe Reader pdf file.
Author: Mike Cline, T/X Resources
Now for the less effective channel map displays:
Initially, I had included this portion in the original posting, “Effective (and Less Effective) Channel Maps” (see above). However, after thinking about it a while, I decided that it was too long, so I broke it up into two postings.
See the larger Adobe Reader pdf file.
As I mentioned in part one, the Channel TWT Color-Filled Map in the first slide of this series of images, is not as definitive because of the poor choice of colorbars. The upthrown fault block colored in red, increases the time range of the colors so much that the middle fault block, where the channel is located, is almost entirely in the green colors. This is the cause for the loss of color contrast, leading to less definitive channel edges. A map’s “dynamic range” (the spread of the largest-to-smallest values) is a key consideration when deciding on a colorbar.
Author: Mike Cline, T/X Resources
How fortuitous! I received my version 8.2 update of SMT’s Kingdom software this afternoon, and just got it installed. One of the new features that has been added to this version of 2d/3dPAK, is the ability to display the Shaded Relief of a grid. So, I thought that this would be a good time to introduce the technique to those viewers not familiar with the general concept. However, since I haven’t had a chance to get completely familiar with this newest feature in the SMT software, the surface and map displays shown below were created in my normal work flow using Golden Software’s Surfer program. As time permits, I’ll try to review, and compare, SMT’s new feature.
What is a Shaded Relief display? It is a map view of an artificially illuminated 3D surface whereby shadows are cast by minor deflections in the surface (shadowed deflections are facing away from the illumination source). This type of map is an excellent way to highlight smaller faults which may not have been seen, or noticed, on the vertical seismic displays.
See the larger Adobe Reader pdf file.