Under the ice

Why this is extraordinary

The ice sheet is a cover. That is not a theory. It is what a sheet does. Under it, in East Antarctica, a Russian station called Vostok sits on a plateau so flat that pilots in the early 1960s wondered if the ice was floating. Seismic shots and, later, radar said the wonder was right. There is a lake. It is about 250 kilometres long, one of the largest bodies of fresh water under the ice anywhere, sealed off by the sheet. The pin for this room is the station, near 78°28′ south and 106°50′ east, because that is where a drill finally went through.

In February 2012 the borehole called 5G entered the lake at a depth of 3,769.3 metres. Lake water rose into the hole and froze. The next season the drillers cored that frozen water. What came up was ice from the top of the lake, not a block of masonry, and not a core of the mud on the lake floor. Papers since then have argued about microbes in that ice, and about contamination from the drilling fluid. The argument is about life and about a dirty hole. It has not produced a worked stone. In January 2013 a different lake, Whillans, on the edge of West Antarctica, was entered with a hot-water drill, and that one did return water and sediment. The sediment held a community of microbes. It was mud and life, which is what a sample of a lake bed looks like when the bed is mud. A British attempt on Lake Ellsworth in December 2012 did not reach the water at all.

Radar is the other way in, and it does not bring a sample home. Ice-penetrating radar, a radio pulse that bounces off the bed, and seismic lines, which are soundings, draw a profile of ice and rock. They have found lakes, troughs, and mountains. The Gamburtsev range, under the East Antarctic ice, was reported by the 3rd Soviet Antarctic Expedition from seismic soundings in 1958. It is a mountain system that does not break the surface. The surveyors published peaks of rock, not walls. The list of lakes itself is a history of a survey that was not finished in one pass. A few were known in the 1960s and 1970s. More than a hundred were listed by the mid-2000s. Later inventories run into the hundreds. Each new lake is water the previous map had not drawn. That is a fact about coverage. It is also the opening the other reading walks through.

One reading says the bed is what the instruments show, repeated often enough to trust the kind of thing down there: ice, water, sediment, and bedrock, including whole ranges. No paper has published a city, a wall, or a tool from beneath the sheet. The other reading says a profile is not a walk. Lines have gaps. A work smaller than the spacing of a survey, or sitting between the lines, would not yet have a paper. The continent has not always worn this ice. The plants, and the step at about 34 million years when a continental sheet grew, are in Forests and the ice. They are linked so this room does not replay them as a verdict. A warmer shore in deep time is a possibility the leaves already require. Whether any such shore still holds a work, or held people who could be drawn on a chart, is the question the instruments have not closed. The charts are in Charts of a southern land. Peaks that already stand in the air, where a building would not need a drill, are in Pyramid-like peaks.

There is no sky alignment to report, and inventing one would be a false star on a lake. Vostok lies near 78° south. With a tilt like the Earth’s now, the station’s year includes a long winter with no sunrise and a long summer with no sunset. That is the sky the drillers worked under, and it would have been the sky of any earlier camp on this plateau. No wall has been published to aim at a solstice, so no azimuth exists to weigh. The forests room is where that polar day and polar night are tied to something that actually grew.