The objective of this research is to establish a validation process for survey correction algorithms, primarily focusing on the application of Multi-Station Analysis (MSA). While MSA represents a mathematical approach to survey error reduction, the application can result in varying levels of achieved accuracy. The adoption of a validation process to assess the accuracy of an MSA provider’s algorithm and processes would provide a framework within which to evaluate different providers.

The research will give an overview of the error sources in the ISCWSA error model and their impact on MWD surveys. A simulated well with survey depths and six-axis data will give a true known position of a well’s bottom hole location. Using the error model, randomized errors will be applied to the six-axis values to create a corrupted bottom hole location. A 3rd party proctor will distribute the corrupted six-axis data of 12 wells in varying azimuthal directions to the MSA provider to process through their algorithm. The corrected wellbore position will be returned to the proctor.

A chi-squared analysis of the results will show if the corrected wellbore positions fall within the expected accuracy level based on the error model. Companies will be assessed on both speed and accuracy. The results of the validation trial will establish the accuracy level that the MSA provider is able to achieve under given circumstances. The levels will be determined using wells inside and outside of the East-West Exclusion zone. The validation process will provide clarity to which error models should be assigned to a set of survey data when using a particular provider. For example, a certain provider might be able to achieve MWD+IFR1 accuracy as opposed to MWD+IFR1+MS under certain conditions. Whether or not checkshots are necessary will also be assessed during the validation process. Additionally, only error sources contained in the ISCWSA error model will be evaluated, and the magnitudes will be within the bounds of what can be reasonably expected in field application. Validation is widely accepted across many industries, including the aerospace and pharmaceutical industries, as a benchmark to ensure the safety of those using their products. As for MSA, improper application could cause inaccurate well placement resulting in well-collisions, or unknowingly crossing lease lines.

When planning a well, an Oil & Gas company will be able to determine which MSA provider is qualified to provide accurate services based solely on the azimuthal direction of their wellbore and the target error model that they would like to achieve. The validation process will provide transparency to the MSA survey correction process and allow Oil & Gas companies to ensure that the purchased product is meeting the advertised accuracy level.

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