“Unlocking the Secrets of Ancient China’s Ingenious Gas Drilling: A Hidden History of Energy Innovation”
Sichuan Province lies roughly in the centre of China, bounded by the Himalayas to the west, the Long Men Mountains to the north, and the Hua Ying Mountains and Yangtze River to the south. Blessed with fertile soil, a mild climate, and abundant water, Sichuan is one of China’s most productive agricultural regions, producing a wide variety of crops from wheat and rice to cotton, tobacco, and mulberry bushes for silkworm cultivation. But the region, which lies on the site of an ancient, dried-up ocean, is also blessed with another, far more valuable resource: salt. Vital both as a nutrient necessary for human metabolism and as an agent for preserving food before the advent of refrigeration, salt has been a major driving force in world history for millennia – so much so that the modern expressions “salary” and “worth his salt” are thought to derive from the practice of paying Roman soldiers in salt. Throughout Chinese history, people living near the coast obtained salt by boiling seawater. However, as settlement spread further inland, the logistics of transporting sea salt from the coasts to the interior became increasingly difficult, and people began seeking a new, more local source of the compound. They found it in Sichuan’s deep aquifers of brine, which contained salt concentrations higher than 50 grams per litre. But while this brine sometimes rose to the surface in natural seeps, much of it lay trapped hundreds of metres below the surface, requiring specialized technology to reach and extract.
