Presentation on theme: "Proving ADAPS via honest results. No well data is input! The well images you see here were super-imposed after the runs were made. The ability to match."— Presentation transcript:
Proving ADAPS via honest results. No well data is input! The well images you see here were super-imposed after the runs were made. The ability to match well results is the best test for any tool that is pretending to improve resolution. I present these great examples as my answer to those seeking mathematical proof. To appreciate what has been accomplished, one must compare the “before and after”. In these examples I match each final result with the best the owner had been able to do using state of the art processing.. Dominant events that were probably mapped completely change character as a result of the powerful detuning. This is illustrated by the shale play to the right where significant changes are verified by excellent well matches. This is the essence of the ADAPS argument. The best possible answer under the conditions that exist is the goal of all optimization software. In the case of ADAPS we set out to explain the energy on the individual traces using all our seismic knowhow. I am the first to say that these matches are not always perfect. However most make me smile. The ADAPS de-tuning is a two part thing. First, it does a superb job of simulating the reflection coefficients (spikes to us). However, once done, these interfaces are often hard to map, since even when the beds extend for miles, the individual spikes may come and go. ADAPS goes one step farther by integrating the spikes to simulate actual lithology. please note that on all the examples there are more events showing on the input than on our output. In other words the system has completely re- arranged the input energy bands according to it’s idea of true lithology. Please take time to examine the improvement, lobe by lobe. A solution looking for the right problems – I have yet to see the prospect where the ADAPS results weren’t an improvement. Of course when the structure is boring the differences might not seem worth the effort. The really exciting cases are where this ultimate de-tuning brings out structural details and reservoir possibilities that otherwise might be missed. One of these is discussed two slides later. The B&A at the right comes from a different shale play. I was happy with the way the system matched the log below the arrow (thickness wise). However the upper section provides great examples of what I said about the re-assembly of the input lobes, reducing the number and greatly improving the well match. pay close attention to the circled zone. One should not have to go further for proof on the the “simulation of a sonic log” (that I tout constantly) is important. What I am looking for – I have already sold the proprietary rites to my non-linear inversion to Ikon Science. They have published an early version as NLI. However, I retained the right to use my work on a consulting and service basis. Each of the projects I have worked on has posed unique challenges. The non-linear ADAPS approach allows me to get my arms around noise problems, generally on a pre-stack basis. My current goal is to establish consulting relations with a few independent companies that have data I can improve. Click on “do it yourself” to return to the ADAPS base or elsewhere to continue with these examples. You are looking at seismic simulations of sonic logs, the ideal for stratigraphic interpretation.
Shale play and seismic- Because of the general fracturing approach, the role for seismic resolution seems diminished. Even though ADAPS has been able to sharply define the lithology and thicknesses of the two deep events, variations in the overlying organic shale are also of great interest. Resolution is even more key here, and while there is a lot of improvement, more needs to be done. Unfortunately, even if we do a perfect job, current automated interpretation systems are not up to the task of translating subtle stratigraphic changes into map form, at least in complex areas. In the ADAPS view, there may still be a place for time slices and other currently popular tools, but only after human evaluation of multi-dimensional results (using old-fashioned visual interpretation). Back to simulated sonic logs!
What I want to show in these next two slides is how ADAPS uncovered a major lensing phenomenon. While there are traces of it on this input, you will see the major difference de- tuning can make in interpretation when you toggle to the next slide. But before you go forgive another lecture on well matches. Too often interpreters look right past the fine detail, just noticing when major things more or less line up, regardless of polarity. The reason this is so important is that these matches supply proof of the ADAPS inversion and sonic log integration. Since so many lobes are removed by the process, final matches are crucial to industry acceptance. On this input match, most matching lobes are just randomly misplaced, while many show opposite polarity. Those to the right should match with blue events of course. On the finished product you will see remarkable agreement. Please take the time to study this by toggling. This is the lensing area mentioned. It is around the target, so the phenomenon is most important to reservoir evaluation. When I first began the study I was convinced there was faulting. Now we will see that ADAPS de-tuning straightened out the complex overlap. Toggle please T The best the client could do – The unadulterated input stack.
And back Now look at the well match! To sell the merits of de-tuning, one has to find an example where it makes a profound stratigraphic difference. This is one of those finds. While I want you to study the fairly remarkable well match before you leave, first pay attention to the stratigraphic pinchout now evident below. A personal vignette – Back in the 50’s, when I was an interpreter for Mobil, I had an offset being drilled on my say so. We were shooting some work to check my interpretation and the paper results were drying in a locked partition. To see them I scaled the wall. Today, I wonder how many still feel the excitement that still drives me in my efforts. The beauty of this well match set me off. ADAPS inverted & integrated output.
Another case where ADAPS made lobes point in the right direction. But also notice the enhanced strike slip fault evidence. Such faulting is discussed in the Nexen show reachable from the ADAPS base. BeforeAfter
Please note the minute well match details, including the polarity flip-flops.
A “post stack” example where parameters were tailored to Vibroseis input. Here I show the results first. Again note the remarkable well match. Please toggle with straight stack input.
The question is: How could anyone have been satisfied with this match?
Rocky mountain (post stack) inversion and integration, line Y
Rocky mountain (post stack) stacked input, line Y Please toggle w results
Of course the display does make a difference. We only use the two basic colors in the ADAPS output. If you go to our section on direct reservoir detection you will see that the bright red being touted as a hydrocarbon indicator. We are careful to adjust the amplitudes so as not to jam. I am sure the complex color scheme at the left is very meaningful in North Sea work, but it offends my own eye. We are back in the Nexen work here, and the first section was presented to introduce me to the problem. The section to the right is the ADAPS output. While it leaves something to be desired, it does seem to beat the hell out of what we started with. The blue event towards the top of the well log is a marker shale we followed all around the prospect We think the correlation across the strike slip vertical fault is as shown. You will see that this is in direct opposition to what the original data showed.. The fact that I could not get Nexen excited about this comparison still blows my mind.