Understanding Logs and Well Data

When you hear the word “log,” you might picture a stack of papers. In oil and gas, a well log is something different — it’s the record of everything found underground.

Logs are created by sending specialized tools down the wellbore. These tools measure the type of rock, how much space is inside the rock (porosity), and whether it’s filled with oil, gas, or water.

Common Types of Logs

• Gamma Ray Logs: Identify rock layers and help separate shale from sand.
• Resistivity Logs: Measure how well rock conducts electricity, which helps locate hydrocarbons.
• Porosity Logs: Estimate how much oil or gas the formation can hold.

Why Logs Matter to Investors

Logs confirm whether a drilling project is likely to produce. A company that shares well log data is being transparent — it’s proof they’re making decisions based on evidence, not speculation.

Logs are one of the main ways operators lower risk and increase confidence before spending more money on drilling. For investors, that means better insight and smarter participation.