Hi Ross - I never realized what we were missing until we started hanging your plots on the walls in structural cross sections. - Jack R.

Integrated Consulting Connecting Logs, Cores, Tests, Productivity, Cash Flow, and Seismic Petrophysics - Since 1973

A PICTURE IS WORTH A 1000 WORDS - A CROSS SECTION IS WORTH A MILLION: We customize our petrophysical presentation to suit the situation. Single well plots can be delivered on paper or in PDF format via email. The integration of core data demonstrates the calibration of the analysis model.

SHALY SAND

Note the close match between petrophysical results (red smooth curves in tracks 3 and 4) with core porosity and core permeability (black squared curves). This is essential to demonstrate a reasonable petrophysical analysis. The parameters developed in cored wells are used in uncored wells.

TAR SAND

Note the close match between petrophysical results (red smooth curves in tracks 1, 3 and 4) with the core data (black squared curves). Here we can check porosity, water saturation, and tar mass because the core analysis of tar sands permits all three results to be measured or computed. There is a gas sand above the "TAR1" marker and gas with residual tar for several meters below the marker, so only the porosity is expected to match. Below the gas, the match is excellent, bearing in mind the different vertical resolution of the logs and core analysis.

Cross sections are very instructive, and can be made by cut and paste of scans or screen grabs. Structural sections of answer plots give far more knformation than raw log data, and are used to solve the geologic problem before the "big mistake". Here are some samples.

MISSISSIPPIAN ALIDA

Structural sections of answer plots give solutions that stratigraphic cross sections fail to achieve, especially when compared to raw log sections. Here the client had a poor producer (welll on right) and drilled a horizontal well here to increase production. Nothing much happened because there wasn't any useful reservoir to begin with. This forensic analysis showed that the water contact had been ignored in the original play development. The well on the left has a different OWC so it is not in the same pool as the other three wells.

MISSISSIPPIAN MIDALE

This forensic analysis showed that the horizontal well had been drilled in the lowest structural location possible (near right hand well) putting it too close to the water contact. Results were disappointing. Well on left is again in a different pool. Results would have been much better had the well been drilled on the structural high nect door.

CUMMINGS SAND

Another forensic analysis showed that the horizontal well had been drilled in the worst location possible. The operator chose to put a horizontal into the thick sand on the right but quickly ended up in the thin sand immediately to the left. The well in fact penetrated the coal three times and the water at least once.

PEKISKO

This project was part of a unitization study I worked on in the early 1970's. The unit committee could not agree on unitization and equity distribution because the pressures on the west half were different than on the east. Support from a water flood in another pool was blamed. The sand channel in the middle of the field was not discovered until much later. It is now clear that the west and east are unrelated pools - no wonder unitization failed. The sand channel is a separate pressure regime so there must be some undrilled shale or tight carbonate preserving its separate identity. Integrating pressure data with the petrophysics solved this situation where geological correlation failed.

NISKU

You just can't win on some projects. Here the match of core porosity and core permeability to the petrophysical results is excellent in 3 out of the 4 zones analyzed. The high water saturation in the Upper Nisku on the right hand well indicates unconneected vuggy porosity. I was chastised for showing a "water zone" in the middle of clean oil production and for not matching core permeability. The second criticism was somewhat deserved (but not easily fixed with the limited available data), but no amount of explanation of irreducible water saturation concepts could solve the first. So the client was unhappy. He later sold the play, with my report. The new owner phoned to say what a fantastic job I had done!