From Qualitative to Quantitative – How Visual Data Analytics has Transformed Downhole Video Diagnostic Services
Authors: Tymons Tobben , Roberts Glyn , Scott Christopher 
Published: August 2019

Video images have traditionally provided intuitive visual analysis in a wide range of wellbore diagnostic situations. Step changes in computer vision techniques and image processing have led to the ability to make measurements from images (visual analytics). This paper demonstrates several applications where the application of this new data analytics source, combined with state-of-the-art acquisition technology, have further improved understanding of complex well issues while reducing operational time, risk and cost. Examples include hydraulic fracturing, well integrity, erosion, restrictions and leaks.

The paper will describe the methods and process of this visual analytics technique through discussion of the three main work flow stages from data acquisition to final analytical product, including the innovative developments in sensor, system and computer vision applications that support each step:Acquisition of full circumferential, depth-synchronized video data of the wellbore. An array of four orthogonally positioned cameras, pointing directly at the pipe wall, concurrently record overlapping images, enabling a continuous full-well video dataset to be obtained.The four depth-matched video streams are synchronized and "stitched" together through the application of computer vision algorithms to provide a continuous 360° map of the wellbore with submillimeter pixel density.Calibration and measurement of the acquired images before new and unique diagnostic enhancing data analysis methods are applied.

The paper will provide real-world examples, presented as case studies, for applications including well integrity evaluation, screen condition assessment, and analysis of perforations. Each case study will demonstrate how visual data analytics used to quantify downhole features, combined with the ability to capture a complete, high definition view of the pipe wall, provides detailed and highly intuitive information that leads to an enhanced understanding of the well and the factors affecting its performance.

We will demonstrate that the application of this visual analytic method, together with the latest generation imaging system, exceeds the limits of conventional logging technologies for multiple industry challenges, such as:Hydraulic fracturing: confirmation and measurement of uniformity of proppant placement to cluster-level and perforation-levelWell integrity: identify corrosion or erosion events, assess their severity and quantify changes with respect to timeWellbore restrictions: understanding of obstructions and their root cause, time-lapse quantification of their extent and progress made with their removal.

The paper will demonstrate that data analytics when applied to images from the latest generation of downhole video imaging systems has enabled the development of new diagnostics methods that provide unique insight on high value operational issues. This step change in information empowers decision-making leading to improved economics and reduced operational risk.