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Sweat the small stuff

Whoever said ‘don’t sweat the small stuff’ had it wrong, and obviously wasn’t in the geophysical business. (My wife once bought me a book by that name, and although I appreciate its advice for everyday life, I don’t accept it in the workplace.) While it is important to see the big picture (see my essay See the big picture), it is equally important to worry about the small details that go into making that big picture. Our profession is made up of specialists and sub-specialists, and each one has a role to play in making sure that the final exploration decision is based on the fundamentals.

Typically, the integrated project involves the following steps: data acquisition, modelling, analysis, and interpretation. When I joined Chevron in the mid-70s, every exploration geophysicist was expected to be on top of all of these aspects of the project. But times have changed, and today no one person can be a specialist in all of these fields. So it is important to make sure that your contribution at the detailed level will fit with all of the other pieces to make an integrated whole

An example

Suppose that your specialty is seismic data processing. An important new consideration for seismic processing is the effect of anisotropy. There are different types of anisotropy and different ways of analysing its effects, for example: in tomography, imaging, and velocity analysis. At your disposal you will have several seismic processing modules, based on some fundamental algorithms. You probably did not develop the algorithms or write the code (this is for other specialists) but this does not mean you don’t have to understand how to use the modules effectively and how to optimize their parameters. This can seem like an overwhelming task. Unlike the situation 35 years ago, when a geophysicist only had to understand the basics of statics, the NMO equation, velocity spectra, post-stack time migration, and a few other fundamentals, the geophysicist of the 21st century has an amazingly complex set of concepts to master. So how would you approach this particular problem?

A suggested strategy

I would first recommend that you get as good a grasp of the fundamentals as you possibly can, either through reading the literature, attending a short course, or talking to in-company experts. Since you cannot be expected to become an expert on all the details, find out what details matter. For example, in the case of anisotropy, you will probably need to understand the Thomsen parameters, so make sure you have read and understood the original 1986 paper by Leon Thomsen. Next, find out how these details pertain to your particular task. This will involve finding the optimum way of extracting the correct parameters and applying them to your data. Finally, look at the results and make sure they make sense. This will be a collaborative task, which will probably involve discussing the result with both your colleagues and the client.

In summary, when I say ‘sweat the details’ I don’t mean all the details, only the important ones. At the end of the process, you should be able to answer a number of questions, such as: ‘Why did you choose those parameters?’, ‘How did it impact the final result?’, and ‘What should we do next?’ Without under­standing the important details, you will never be able to give good answers to these questions.


References

Thomsen, L (1986). Weak elastic anisotropy. Geophysics 51 (10), 1954–66, DOI 10.1190/1.1442051.

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