velocity image

1. n. [Production Logging]
A two-dimensional display, using colors or different gray scales, of the bubble velocity around the borehole against depth. The x-axis of the image shows different segments of the borehole, normally inside a casing, displayed from the top of the hole clockwise around through the bottom and back to the top again. Depth is in the z-axis, while the values of bubble velocity are represented by different colors or changes from black to white. The velocity image is constructed from between four and eight local probe measurements using interpolation within constraints. Images, sometimes called maps, are also made for bubble count and holdup.
Synonyms: velocity map