Cable-tool percussion drilling for brine
Perforación por percusión con cable para salmuera
- Date
- century I a.C.-I d.C. · confidence low
- Place
- Zigong, Sichuan, China
- Credited to
- Sichuan salt workers (Han dynasty)
- Field
- Tools
⚠️ Disputed: the sources disagree.
What it is
Wells drilled by dropping an iron bit hung from bamboo cables from a tower, to reach underground brine. Han reliefs show well towers; by the Song period narrow wells were already being cased with bamboo.
The date of the first drilled (as opposed to dug) wells is imprecise; cable-tool percussion drilling passed to the West in the 19th century.
What it led to
- mass salt production in inland China
- discovery of natural gas in the wells