Lithostratigraphic images

Start with purpose and scope. Identify what kind of log it is (lithological, gamma ray, resistivity, multi‑track well log), the interval shown, and what the reader is meant to learn from it. Describe depth progression, not visual orientation. Logs are read by depth, not by left/right or color bands. Always state the depth direction and interval (e.g., “from 0 to 1,200 meters depth”). Summarize trends and boundaries, not every curve. Screen reader users cannot efficiently consume continuous curves. Focus on: major lithologic changes formation boundaries notable anomalies or patterns Name variables explicitly and explain what high/low means. For geophysical logs, say what is being measured and how changes are interpreted (e.g., “higher gamma ray values indicating shale‑rich intervals”). Avoid color- or symbol‑dependent meaning. If color or shading distinguishes lithologies, translate that into words (e.g., “sandstone intervals alternating with shale”). Use short alt text plus a long description for complex logs. Multi‑track well logs almost always exceed reasonable alt‑text length and should be paired with a long description or data table.