Author: Mike Cline, T/X Resources
As I mentioned in the previous post on seismic inversion, using zero-phase seismic data as an input for inversion, is one of the most critical elements for accurate results. However, this brought up the question of “how bad is bad”, when it comes to phase-matching errors? So, to answer this question, I had an idea to test the sensitivity of inversion results based on the phase of the input data.
Below, is a series of inversion images which were produced from the same initial synthetic seismogram. However, prior to generating the inversion, I rotated the phase of the input data in the amount indicated at the bottom of each image—that is: 0, 45, 90, 180, 270, and 315 degrees.
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
Imagine a wall of water, with a flow rate of over one million cubic meters (35.31 million cubic feet) per second, rushing towards you—an amount that is 100 times the average flow rate of the Mississippi River today!
If you were crossing the broad chalk ridge (indicated by the thin, red line in the gray-shaded image below) that connected Britain with mainland Europe sometime between 200,000 and 450,000 years ago, you could have witnessed this ridge-busting torrent that ultimately separated the two countries.
See the larger Adobe Reader pdf file (two pages).
You can also watch a video report from the BBC News.
Author: Mike Cline, T/X Resources
I’m sure by now, most of our blog visitors have heard about external hard drives. However, if you aren’t familiar with them, they simply allow you to add a hard drive to a computer by attaching it externally (via a plugin socket), instead of having to take the computer apart, and installing the drive internally.
This technology, which is commonly used for storing data, or backup files, has essentially replaced most tape drives. It has been around for quite a while, so I would also guess that many have even purchased “ready-built” enclosures, or like me, built their own.
See the larger Adobe Reader pdf file.
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
Here are the results from another one of my Do-It-Yourself spreadsheet applications. This one creates a pseudo-shear log from a sonic log, using John Castagna’s “Mudrock Line” technique.
Often, shear sonic logs are difficult to acquire, so we may end up using a “default” shear log suggested by our AVO programs, which commonly use either a Poisson’s Ratio of 0.25, or a Vp/Vs ratio of about 2.0 to calculate the shear log.
However, there is a much better way, which Castagna illustrates in his classic 1985 paper (long title) “Relationships Between Compressional-Wave and Shear-Wave Velocities in Clastic Silicate Rocks”. In his article, he demonstrates that there is an excellent linear relationship between the compressional, and shear velocities of clastic silicate rocks, a technique which I have used many times, with successful end-results for many of my clients.
See the larger Adobe Reader pdf file.
Author: Mike Cline, T/X Resources
How cool is this? I just found a new online spreadsheet application that allows you to share, collaborate, and publish spreadsheets that actually work when they are posted on a website, or blog. EditGrid received a very good rating from PC Magazine. The concept is somewhat similar to what is already being done with the online spreadsheet applications of Google Docs, and Zoho. However, the company focuses all of its efforts on the spreadsheet application solely, and apparently does a much better job at it, than either of its competitors.
Author: Mike Cline, T/X Resources
This posting is an update of the ”Active Domestic Drilling Rigs and Seismic Crew Count” statistics which I created, and originally posted on the HGS GeoJob Bank ”GeoJob & Energy Statistics” page. However, the HGS page has not been updated since I “retired” as Chair of the Personnel Placement Committee, so I have decided that I would continue updating, and posting the graph here.
See the larger Adobe Reader pdf file.
Author: Mike Cline, T/X Resources
For those of you that haven’t had a chance to try out the Coblending feature in version 8.2 of SMT’s VuPak module yet, I would suggest that you give it a look. If you’ve never used anything like it before, be aware that it could max out your wowie-meter! Excuse the enthusiasm, but I like cool (and useful) technology.
(Back in the real world now) What is Coblending? It is just as its name implies—it is the ability to blend two different volumes of seismic data together, and display them both at the same time. Besides being very cool, it could also really be helpful with seismic interpretations—especially in complexly faulted areas.
See the larger Adobe Reader pdf file.
See the VuPak animation
Note: The avi file is fairly large, so it will take some time before the animation starts.
Author: Mike Cline, T/X Resources
For anyone who experienced the fluctuations in the oil business during the last 30 years or so, the descriptive “roller coaster ride” in the title only partly explains our adventures.
At the time of the hiring peak of the oil industry—December 1981—there were nearly 1.18 million people employed in the mining industry (a Bureau of Labor Statistics category which includes the oil industry), as seen on the blue employee graph in the image below (generated with Golden Software’s Grapher program).
Oil prices had just peaked at $34.59 per barrel (average monthly price) nine months earlier, but it was still selling at nearly $31 per barrel that December. During the same time period however, March to December 1981, industry unemployment had crept up to 7.5 percent, from just 4.4 percent (black graph in the image below)—an increasing trend that went unappreciated by most of us at the time.
See the larger Adobe Reader pdf file.
Author: Mike Cline, T/X Resources
I got the idea for today’s posting from a client’s search for a critical well log—he’s been searching for it for a while now, but hadn’t been able to find it, so far. So, I suggested a few more companies to search, and hence this posting. Since logs are so important for what we do as geoscientists, I thought that the list of sources (in no particular order) that I sent to him, might be helpful to others, as well.
IHS has millions of feet of world-wide coverage of digitized logs, and raster images at: http://www.ihslognet.com/
TGS also has world-wide coverage of digital LAS log files, and raster logs at: http://www.tgsnopec.com/data_solutions/geological_products_services.asp
Author: Mike Cline, T/X Resources
Anyone who has visited the Houston Geological Society’s (HGS) GeoJob Bank, or more specifically the GeoJob & Energy Statistics page, is bound to recognize this graph. During my nearly six-year tenure (2000-2005) as Chair of the Personnel Placement Committee, I created and updated the industry-related graphs on the Statistics page (amoung my many other duties). However, since I “retired” from the Committee in late 2005, the graphs haven’t been updated, so I thought that this would be a good venue to revive some of the graphs, and keep them current with updated information.
This first graph, in a series to come, is the oil and natural gas price curves for 35-years—from January 1973, through the last available data in December 2007. It was created from downloadable data from the U.S. Department of Energy’s (DOE) Energy Information Agency, and the Federal Reserve Bank of St. Louis, saved to a spreadsheet, and then graphed with Golden Software’s Grapher program.
See the larger Adobe Reader pdf file.
Author: Mike Cline, T/X Resources
If you’re like me you probably spend long hours at the computer. Because of this, it’s easy to develop Repetative Stress Injuries (RSI) if you’ve improperly positioned yourself, your computer equipment, or your office furniture.
I just ran across a few websites that may be helpful and informative as to the proper, ergonomic placement of these items.
The U.S. Governments Occupational Safety & Health Administration (OSHA) website provides a lot of useful information concerning Computer Workstations, and provides a Workstation Checklist, and Workstation Purchasing Checklist, Good Working Positions, and Selecting Workstation Components .
Even with the correct design and placement of the workstation, RSI can become a problem unless the risk factors are reduced by Work Process and Recognition, and the Workstation Environment.
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.