To answer your questions, after drilling a well, a tool with 8 spring loaded pads is lowered to the bottom of the well. The springs activate and push the pads against the rock of the wellbore, then slowly dragged to the surface. The vertical gray bands are gaps between the pads, and therefore gaps between the data in the image.The vertical gray bands distort towards the top of the image because the pads were rotating in the wellbore. The final image is an oriented flat projection of a 360 degree image of the rocks surrounding the hole.
Read more about it here ( https://www.slb.com/services/characterization/geology/wireline/fullbore_formation_microimager )
I’ll see if I can find an image without the gray bands, though I don’t know if it will be any more useful. The bands represent real gaps in the data.
The resolution isn’t very high, but that is the nature of the tool, not from image processing.
The tool measures resistivity. High resistivity is yellow, low resistivity is black. Resistivity varies with rock type, so when there is a sharp boundary between a highly resistive bed and a low-resistivity bed, I can confidently say that surface represents a surface between two different rock types.
The surfaces are roughly horizontal, but some of them dip (see the wavy looking horizontal surfaces near the top of the image). Right now I am doing a vertical compression of the images to flatten the non-horizontal beds.
I hope that helps. Let me know if you have any more questions