Anomalies Observed on Well Logs


Gregory W. Hammack,
Walter H. Fertl,
Continental Oil Company



Since the first electric log run in 1927, thousands of well logs have since been produced which aid in a realistic evaluation of subsurface formations. However, many of these logs have been misinterpreted be- cause of either some natural occurring phenomena or erroneous log measurements going undetected. Even with today’s advanced interpre- tation techniques combined with the most sophisticated computer log analysis many of these anomalous logs are still overlooked. The experienced log analyst can help in avoiding costly and erroneous decisions by recognizing these anomalies.