Oil well

Lore & Background

The oil was burned to evaporate brine producing salt. By the 10th century, extensive bamboo pipelines connected oil wells with salt springs. Ancient records of China and Japan contain many allusions to the use of natural gas for lighting and heating. Petroleum was known as burning water in Japan in the 7th century. According to Kasem Ajram, petroleum was distilled by the Persian alchemist Muhammad ibn Zakarīya Rāzi (Rhazes) in the 9th century, producing chemicals such as kerosene, mainly used for lamps. Arab and Persian chemists also distilled crude oil for flammable military products. Through Islamic Spain, distillation became available in Western Europe by the 12th century. Some sources claim that from the 9th century, oil fields were exploited near modern Baku, Azerbaijan, to produce naphtha. Marco Polo in the 13th century described those oil wells as producing hundreds of shiploads. The earliest oil wells in modern times were drilled percussively; in the 20th century, cable tools were largely replaced with rotary drilling, which could drill boreholes to much greater depths and in less time. Until the 1970s, most oil wells were essentially vertical, but modern directional drilling technologies allow for highly deviated and horizontal wells, increasing production rates and enabling access to reservoirs kilometers away.

Reader's Guide

Oil wells are fundamental to the modern petroleum industry, enabling the extraction of hydrocarbons that power economies and industries worldwide. Their development spans from ancient Chinese bamboo-drilled wells to sophisticated rotary and directional drilling technologies of the 20th century. The economic significance of oil wells is underscored by their status as assets frequently sold or exchanged between companies; even low-production wells may become valuable when oil prices rise, and new methods such as hydraulic fracturing have made some wells viable. However, peak oil and climate policy surrounding fossil fuels have made fewer of these wells and costly techniques viable. A major environmental concern is neglected or poorly maintained wellheads, which may leak methane or other toxic substances into local air, water and soil systems. This pollution often becomes worse when wells are abandoned or orphaned—where a well is no longer economically viable and no longer maintained by its former owners. A 2020 estimate by Reuters suggested that there were at least 29 million abandoned wells internationally, creating a significant source of greenhouse gas emissions worsening climate change. The life of a well involves careful planning, drilling, and completion, with modern wells often having multiple casing strings to isolate pressure zones and protect formations.

Did You Know?

• A 2020 estimate by Reuters suggested at least 29 million abandoned wells internationally.
• Modern directional drilling allows wells to become horizontal, increasing surface area in the production zone.