A detailed sketch of a cross-section of a horizontal well drilling through various geological formations. The illustration should show the wellbore starting vertically from the surface, then curving to become horizontal as it penetrates different layers of rock. Label the different formations, such as shale, sandstone, and limestone. Include annotations for key features like the drill bit, casing, and drilling fluid. The sketch should provide a clear visual representation of the horizontal drilling process and the geological layers encountered