Singapore has embarked upon the excavation of an underground oil reserve, expanding the city's industrial port beneath the floor of the Pacific Ocean. It is "no ordinary construction site," the BBC tells us, but an elaborate project of engineering and infrastructure currently underway "several hundred feet underground, below the seabed in Singapore."

There, workers are "laboring around the clock to carve out an enormous network of caverns that will eventually store vast amounts of oil."

More specifically, "Five oil storage caverns are being dug out under the seabed of Banyan Basin, off Jurong island, a series of mostly-reclaimed islands that house most of Singapore's petrochemical industry."

Artificial caverns built offshore from manmade islands?

The terrestrial mechanics of Singapore's existence are increasingly interesting, if ecologically problematic. As Pruned's recent look at the city's sand-importation economy shows, the island-nation exists through a near-ceaseless act of geological accumulation, piecing itself together and expanding from the inside out using deposits of earth taken from neighboring countries.

Singapore, Pruned writes, "has been reclaiming land from the sea since the mid-1960s, expanding its total land area by nearly 25% as a result. And it's still growing. With no hinterlands to supply it with natural resources, however, it has to import sand, the primary landfill material. But exactly where, the Singaporean government does not disclose. Its supply lines are not public information."

Earlier this year, we looked at the idea of forensic geology, whereby even a single piece of sand can be tracked back to its terrestrial origins. As that link explains, the source of electronics-grade silicon is often deliberately occluded from public documents, treated as an industrial trade secret. Here, though, it is not microchips but internationally recognized political territory that is being mined, traded, and assembled-a black economy without audit or receipts.

Singapore's off-the-books experiment in sovereign expansion-not through military conquest but through intelligent geotextiles, Herculean dredging projects, and, of course, new undersea caverns-is perhaps a kind of limit-case in how nation-states not only utilize natural resources but literally build themselves from the ground up (and down) as political acts of landscape architecture. (Earlier on BLDGBLOG: Artificial Caverns Expanding Beneath Chicago.)

This post originally appeared on BLDGBLOG.