Advances in seismic processing are allowing oil and gas companies to book higher reserves
One of the most important factors affecting an oil and gas company’s finances and share price is its reserve base—the volumes of gas or oil it figures it has in the ground that can be economically produced using currently available technology. Because bankers and investors place much faith in a company’s reserves, they’re a hot topic with the US Securities and Exchange Commission (SEC) and how they are determined has become highly regulated. Trouble is, reserve levels can become a moving number as technology improves.
So, many have welcomed seismic technology developments like tilted transverse isotropic (TTI) migration. Sounds like a mouthful, but it’s a result of the modern trends in seismic to generate often several terabytes of data and use clever algorithms in their processing. It seems to fit what the SEC considers “a reliable technology” for delineating reserves says the industry.
What does it do? What TTI migration does is allow explorers a way of dealing with how anisotropic properties of the near subsurface often mislead a seismic result. It allows them to track how the waves are bent. Shale, for example, can be stiffer in one direction because of its layering and be weaker in another; or can be fractured, all of which can skew the reservoir image.
An imprecise image could easily make several millions of dollars difference on a balance sheet. So continued use of TTI assists in delineating the reservoir—tells you more accurately where to drill the next well to define the reservoir’s edge, and it’s clearly important to hit the edge as close as you can without going outside it and missing. This done accurately, a company can essentially claim the entire zone as reserves, enhancing its reserve base and thus borrowing and shareholder value.