Drilling since 2011 · Site KX-4, Antarctica

Air that stopped moving.

We drill one hole in Princess Elizabeth Land and allocate what is trapped inside it. The deepest sample we hold closed at 3,270.4 metres, 1.14 million years ago, and has never been breathed.

Request core time Borehole log

01Firn · 0–96 m

The first ninety-six metres are still breathing.

Above close-off the snowpack is porous. Air moves down through it, mixes, and dates younger than the ice around it — by 240 years at Site KX-4. Nothing in the firn is evidence. We log it anyway, because a log with a hole in it is not a log.

Accumulation: 38 mm ice eq. / yr
Density at 96 m: 0.830 g/cm³
Gas age offset: 240 yr
Mean surface temp: −52.0 °C

Core face at head depth

02 — Close-off

At ninety-six metres the ice stops taking calls.

Pore space pinches shut. Each bubble becomes a sealed sample of the atmosphere on the day it closed, held at 6.1 bar and −52 °C. Below this line the core is not ice with air in it. It is a stack of dated envelopes, 4.2 metres at a time, and we are the only people who open them.

0.10 cm³ air per gram
6.1 bar enclosure pressure
96.2 m mean close-off

03

Ice becomes evidence in ninety seconds.

The segment does not come back. Every metre we read is a metre we destroy — so we read it once, at two millimetres a second, and write down everything.

Melt head · 24 °C ring

1Shave
2Melt
3Spectrometer
4Vial

Segment 214-B 0.00 / 4.20 m

Meltwater 0.00 / 3.14 L

CO₂ · laser — ppm

Segment 1,050.0 – 1,054.2 m · last glacial maximum

04The record · 3,270.4 m

Everything we know, in one column.

CO₂ ppm against depth

Borehole KX-4

Spudded: 14.02.2011
Total depth: 3,270.4 m
Bedrock standoff: 11.6 m
Inclination at TD: 2.4°
Oldest gas age: 1.14 Ma

Drill string

Core diameter: 98 mm
Barrel length: 4.20 m
Fluid: Estisol 140
Runs to date: 779
Deepest run: 3,270.4 m

Archive & allocation

Store temperature: −52.0 °C
Held on site: 2,890 m
Released per year: 640 m
Institutions: 11
Applications close: 30.09

05Instrument · operator control

Take the head anywhere in the hole.

Drag the probe. Arrow keys, Page Up / Page Down, Home / End.

Head depth 1050.0m

Last glacial maximum

Gas age: 21.4 ka BP
CO₂: 189 ppm
Temperature anomaly: −8.9 °C
Annual layer: 10.5 mm
Segments to this depth: 250

Core face at the depth you set

Nine hundred thousand years of weather, in a room the size of a squash court, at minus fifty-two.

07Access

Request core time.

We release 640 metres of core per year across eleven institutions. Applications close 30 September. Destructive requests need a second signature and a stated reason we cannot get the same answer from an existing dataset.

allocation@kryos.aq Read the log first

Depot: Novolazarevskaya
Season: Nov – Feb
Radio: +672 4 1188
Shipping: −50 °C, unbroken chain