EARTH × LIFE

The First Phosphate Boom

~630 to 574 million years ago

Proterozoic · Neoproterozoic · Ediacaran

Phosphate began to pile up on the seafloor in quantities worth mining, for the first time in the planet's history. The Doushantuo beds of South China, laid down between 630 and 574 million years ago, still supply a large share of the world's phosphorus, and they formed while the first large eukaryotes were spreading through the same seas.

Why it matters

Over long timescales, phosphorus is what caps how much life an ocean can carry: it is the nutrient that runs out first. Rock made of the stuff is therefore a receipt. Whatever else the sea was doing, more phosphorus was passing through it than ever before, and it was burying the surplus.

Dating & uncertainty

Two separate pulses rather than one. The lower beds, around 630 to 600 Ma, carry the chemical signature of rivers stripping the continents; the upper beds, around 587 to 574 Ma, that of deep water welling up. Whether either caused the rise of animals or merely accompanied it is unresolved.

Sources

1. Fan et al. (2024), Earth and Planetary Science Letters · Phosphorus flux during the Ediacaran: rooted in continental weathering or pelagic upwelling?
2. Jiao et al. (2024), Journal of Earth Science · Integrated stratigraphy and mineralogy of the Doushantuo Formation in Weng'an, South China, and implications for Ediacaran phosphogenesis
3. Cook & Shergold (1984), Nature · Phosphorus, phosphorites and skeletal evolution at the Precambrian-Cambrian boundary

Earth history as one day

20:40:103 h 20 min before midnight

if Earth’s 4.54 billion years were compressed into a single day