Who Needs Seismic Survey Quality Control? -- An Objective Approach

By

Andrea Collins¹

(1) Exploration Consultants Limited, Henley-on-Thames, Oxon, United Kingdom

 There are many differing points of view with regard to the use of Independent Quality Control on seismic surveys. Sometimes it is not easy to be objective about this process when the whole picture may not be seen. The aim of this presentation is to provide those of you with experience in upstream or downstream operations with a fair, balanced view of Independent QC.

It should be accepted that any process is not successful 100% of the time. Therefore it is advisable to check the output from each process or a sequence of processes. The check itself is another process and therefore has a success rate also, but the overall success is increased significantly. This concept can be likened to layers of paper superimposed upon one another each having a few randomly placed holes. The aim is to stack enough layers together so that there are no holes in the final combined product. Each sheet is equivalent to a quality control process to help avoid problems.

If this concept is applied to seismic surveys, it can be seen that more QC equates to a better product.

However, the cost in providing this extra QC has to be viable. Is it worth it?

In the case of speculative work, the ‘independence’ factor of the QC has to be introduced. If the product is to be sold, the buyer will prefer to know about the reliability and validity of the product. The client (in this case the contractor or Energy Company) therefore requires a dataset that can be shown to be within the bounds of the buyer’s specifications. Through procedures and software tools, this presentation shows how the QC can give added value to the dataset.

Quality Control is primarily applied to HSE, crew efficiency, navigation and seismic data.