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Sea 19 m deep

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Metres

A planet

in shock

Earth in the hours,

years and millennia

after the impact

TIMELINE

HOURS

Huge earthquakes,

megatsunamis up to 300m

high, winds of over 1,000km/h

and rampant wildfires result in

instant annihilation for many

species.

WEEKS

Dust from the impact and

soot from wildfires block

out sunlight for many

years. Plants that survived

the impact soon struggle.

Food webs start to unravel.

YEARS

Prior to the impact, non-avian dinosaurs are already in decline, but

the impact seals their fate. If any species survive the impact, it’s not

for long. Over 90 per cent of all mammal species also go extinct. The

largest mammals are hardest hit; the survivors are all smaller than a cat.

On land, forests and flowering plants struggle with the low light levels,

resulting in a preponderance of species like ferns, algae and moss.

0m

Seabed.

503m

Coring begins. As the focus of the expedition is on the

impact crater, the scientists race through the first 500m

of limestone before beginning to pull up cores of rock, 3m

at a time.

550m

Algal blooms. Around 55 million years ago, some 10

million years after the asteroid impact, the Earth was around

5°C warmer than at present. Scientists are hoping to recover

black shales, the geological remnants of carbon-rich algal

blooms predicted to have thrived in the warmer conditions.

550-620m

Approaching ground zero. As the drill reaches the top of

the impact layer, the ecology is expected to thin out to just a

few, rather simple species. By studying the chemical make-up

of the very first foraminifera to colonise the site after the

impact, it should be possible to infer the local conditions at

the time.

620-740m

The impact layer is a chaotic mix of fragmented rocks

and melt that settled in the minutes and hours after the

asteroid hit. It could contain microorganisms that took up

residence in the aftermath to capitalise on the rich chemistry.

740-1,335m

The peak ring. By paying special attention to the age

and sequence of rocks in the peak ring, geologists hope to

solve the mystery of how these structures form. Satellite

data indicates that the rock in the peak ring is not as dense as

it might be. Are there cracks and fissures, and what kind of

microbes might live in these voids?

CROSS-SECTION

OF THE CRATER

PHOTO: SCIENCE PHOTO LIBRARY ILLUSTRATION: ACUTE GRAPHICS

SCIENCE