The 1IWRP technical program was closed with a one-hour brainstorming session; an attempt to capture the main issues and ideas moving forward.
Creating a common model and data sharing
To truly understand the physics of rocks one really needs a test case where the answer is entirely known across all length scales of measurement. A verbal proposal was made to start a task force for creating a shared rock physics earth model. Something similar to the Marmousi SEG synthetic data set for wave propagation and seismology. A rock physics data set would ideally comprise of synthetic and real data, and not just dynamic elastic measurements. A comprehensive database spanning a suite of physical phenomena within a study area of commercial importance; core, full waveform sonic logs, petrophysical measurements, seismic.
What is the future of digital rock physics?
The nature of tiny cracks, grain contact surfaces, and cements in sedimentary rock are at the limits of visibility and, somewhat ironically, these tiny effects dominate the material's elastic properties. Digital imaging can be enriched and validated by, not a replacement for, thin-section petrography. Furthermore, determining the porosity of shales using digital methods will be increasingly in demand. Dealing with small sample sizes, sample bias, and scale dependant effects is another challenge that was noted. Making this relevant at the reservoir scale is a challenge pertinent to the whole petroleum industry.
Unsolved problems in upscaling and scale dependant measurements
One of the main themes in geoscience is the challenge of extrapolating measurements or observations at one scale, to larger or smaller scales. In response to the question, "how do we deal with upscaling and scale dependant measurements?" The room fell silent. Then someone shouted out, "we should write more papers about it!" Permeability upscaling has been studied extensively and widely published due to it's overridding importance, but less so with other physical phenomena. One example is the problem of scaling or calibrating sonic-log anisotropy to study seismic anisotropy away from well control. Is it always empirically-driven or are there theoretical scaling laws?
Certainly, rock physics is required for building a consistent earth model for imaging beneath salt, but this topic was somewhat dismissed as a seismic imaging / seismic processing problem.
Link between rock physics and geomechanical applications
Issues discussed were:
- Rock physics basis for describing and predicting fracacbility
- Geomechanical models needs to be linked with a robust geologic model
- Seismic scale sequence stratigraphy for geomechanics
- Understanding the difference between static and dynamic elastic moduli and their influence on fraccability
- Sampling bias, conflicting data, and hearsay
- Acknowledging uncertainty
- First-of-its-kind workshop — Preview blog post
- Digital rocks and accountability — Day 1 review
- More 1IWRP highlights — Review, continued
- The last chat chart — The wrap-up discussion
- 1IWRP — official site